Mudança Média Método Definição Em Estatísticas

Definição A dor é um sentimento desagradável que é transmitido ao cérebro por neurônios sensoriais. O desconforto sinaliza danos reais ou potenciais ao corpo. No entanto, a dor é mais do que uma sensação, ou a consciência física da dor também inclui a percepção, a interpretação subjetiva do desconforto. A percepção fornece informações sobre a localização, a intensidade e a importância da dorx0027s. As várias respostas conscientes e inconscientes tanto à sensação como à percepção, incluindo a resposta emocional, adicionam uma definição adicional ao conceito geral de dor. Descrição Dor surge de qualquer número de situações. A lesão é uma causa importante, mas a dor também pode surgir de uma doença. Pode acompanhar uma condição psicológica, como a depressão, ou pode até ocorrer na ausência de um gatilho reconhecível. Dor aguda A dor aguda geralmente resulta de dano tecidual, como uma queima de pele ou osso quebrado. A dor aguda também pode ser associada a dores de cabeça ou cãibras musculares. Este tipo de dor geralmente desaparece à medida que a ferida cura ou a causa da dor (estímulo) é removida. Para entender a dor aguda, é necessário entender os nervos que o sustentam. As células do nervo, ou neurônios, desempenham muitas funções no corpo. Embora seu propósito geral, fornecendo uma interface entre o cérebro e o corpo, permaneça constante, suas capacidades variam amplamente. Certos tipos de neurônios são capazes de transmitir um sinal de dor ao cérebro. Como um grupo, esses neurônios sensíveis à dor são chamados nociceptores e praticamente todas as superfícies e órgãos do corpo estão conectados com eles. A parte central dessas células está localizada na coluna vertebral, e eles enviam projeções semelhantes a cada parte do corpo. Nociceptores são classificados de acordo com o estímulo que os leva a transmitir um sinal de dor. Os nociceptores termorreceptores são estimulados por temperaturas potencialmente prejudiciais aos tecidos. Os nociceptores mecanorreceptores respondem a um estímulo de pressão que pode causar lesões. Os nociceptores polimodais são os mais sensíveis e podem responder à temperatura e pressão. Os nociceptores polimodais também respondem aos produtos químicos liberados pelas células na área de onde a dor se origina. As terminações das células nervosas, ou os receptores, estão na sensação da dor dianteira da dor. Um estímulo nesta parte do nociceptor desencadeia uma cascata de neurotransmissores (produtos químicos que transmitem informações dentro do sistema nervoso) na coluna vertebral. Cada neurotransmissor tem um propósito. Por exemplo, a substância P relata a mensagem da dor aos nervos que levam à medula espinhal e ao cérebro. Esses neurotransmissores também podem estimular os nervos que levam de volta ao local da lesão. Esta resposta leva as células da área lesada a liberar substâncias químicas que não só desencadeiam uma resposta imune, mas também influenciam a intensidade ea duração da dor. Dor crônica e anormal A dor crônica refere-se a dor que persiste após uma ferida, dor de câncer, dor relacionada a uma doença persistente ou degenerativa e dor prolongada por causa não identificável. Estima-se que uma em cada três pessoas nos Estados Unidos experimentará dor crônica em algum momento de suas vidas. Destas pessoas, aproximadamente 50 milhões são parcialmente ou completamente desativados. A dor crônica pode ser causada pela resposta do corpo a uma dor aguda. Na presença de estimulação contínua de nociceptores, mudanças ocorrem dentro do sistema nervoso. As mudanças no nível molecular são dramáticas e podem incluir alterações na transcrição genética de neurotransmissores e receptores. Essas mudanças também podem ocorrer na ausência de uma causa identificável, um dos aspectos frustrantes da dor crônica é que o estímulo pode ser desconhecido. Por exemplo, o estímulo não pode ser identificado em até 85 dos indivíduos que sofrem dor nas costas. Os cientistas há muito reconhecem uma relação entre depressão e dor crônica. Em 2004, uma pesquisa de adultos da Califórnia diagnosticados com transtorno depressivo maior revelou que mais de metade deles também sofria de dor crônica. Outros tipos de dor anormal incluem alodinia, hiperalgesia e dor de membro fantasma. Esses tipos de dor geralmente surgem de algum dano ao sistema nervoso (neuropático). Allodynia refere-se a uma sensação de dor em resposta a um estímulo normalmente inofensivo. Por exemplo, alguns indivíduos que sofreram danos nos nervos como resultado da infecção viral experimentam dor insuportável apenas com o peso leve de suas roupas. A hiperalgesia é um pouco relacionada com a alodinia, na medida em que a resposta a um estímulo doloroso é extrema. Neste caso, um estímulo leve da dor, como um pin pin, causa uma resposta máxima à dor. A dor do membro fantasma ocorre depois que um membro é amputado, embora um indivíduo possa estar faltando o membro, o sistema nervoso continua a perceber dor proveniente da área. Causas e sintomas A dor é o sintoma mais comum de lesão e doença, e as descrições podem variar em intensidade, de uma simples dor a uma agonia insuportavel. Nociceptores têm a capacidade de transmitir informações ao cérebro que indicam a localização, a natureza e a intensidade da dor. Por exemplo, pisar em um prego envia uma mensagem cheia de informações para o cérebro: o pé experimentou uma ferida de punção que dói muito. A percepção da dor também varia dependendo da localização da dor. Os tipos de estímulos que causam uma resposta à dor na pele incluem picar, cortar, esmagar, queimar e congelar. Estes mesmos estímulos não gerariam muita resposta no intestino. A dor intestinal surge de estímulos tais como inchaço, inflamação e distensão. A dor é considerada em vista de outros sintomas e experiências individuais. Uma lesão observável, como um osso quebrado, pode ser um indicador claro do tipo de dor que uma pessoa está sofrendo. Determinar a causa específica da dor interna é mais difícil. Outros sintomas, como febre ou náusea, ajudam a diminuir as possibilidades. Em alguns casos, como a dor lombar, uma causa específica pode não ser identificável. O diagnóstico da doença que causa uma dor específica é ainda mais complicado pelo fato de que a dor pode ser encaminhada para um site de pele que não parece estar conectado ao local da origem da dorx0027s. Por exemplo, a dor decorrente do acúmulo de líquido na base do pulmão pode ser referida ao ombro. Como a dor é uma experiência subjetiva, pode ser muito difícil comunicar sua qualidade e intensidade exatas a outras pessoas. Não há testes de diagnóstico que possam determinar a qualidade ou intensidade de uma dor individualx0027s. Portanto, um exame médico incluirá muitas perguntas sobre onde a dor está localizada, sua intensidade e sua natureza. As perguntas também são direcionadas para o tipo de coisas que aumentam ou aliviam a dor, quanto tempo durou e se há alguma variação nela. Um indivíduo pode ser solicitado a usar uma escala de dor para descrever a dor. Uma dessas escalas atribui um número à intensidade da dor, por exemplo, 0 pode indicar que não há dor e 10 podem indicar a pior dor que a pessoa já experimentou. As balanças são modificadas para bebês e crianças para acomodar seu nível de compreensão. Existem muitas drogas destinadas a prevenir ou tratar a dor. Analgésicos nãoopioides. Analgésicos narcóticos, fármacos anticonvulsivantes e antidepressivos tricíclicos funcionam bloqueando a produção, liberação ou absorção de neurotransmissores. Drogas de diferentes classes podem ser combinadas para lidar com certos tipos de dor. Os analgésicos nãoopioides incluem medicamentos comuns em balcão, como a aspirina. Acetaminofeno (Tylenol) e ibuprofeno (Advil). Estes são mais frequentemente utilizados para dor menor, mas existem alguns medicamentos de prescrição médica nesta classe. Os analgésicos narcóticos só estão disponíveis com receita com um médico x0027 e são usados ​​para dor mais intensa, como dor de câncer. Esses medicamentos incluem codeína, morfina e metadona. O vício para esses analgésicos não é tão comum quanto pensou. Muitas pessoas que realmente precisam dessas drogas para controlar a dor tipicamente não se tornam viciadas. No entanto, o uso de narcóticos deve ser limitado aos pacientes que pensam ter um período de vida curto (como pessoas com câncer terminal) ou pacientes cuja dor só deverá durar pouco tempo (como pessoas que se recuperam de uma cirurgia). Em agosto de 2004, a Drug Enforcement Administration (DEA) emitiu novas diretrizes para ajudar os médicos a prescrever narcóticos adequadamente, sem medo de serem presos por prescrever drogas além do alcance de suas práticas médicas. A DEA está tentando trabalhar com os médicos para garantir que aqueles que precisam de medicamentos os recebam, mas para garantir que os opióides não sejam abusados. Anticonvulsivantes, bem como medicamentos antidepressivos. Foram inicialmente desenvolvidos para tratar convulsões e depressão, respectivamente. No entanto, descobriu-se que essas drogas também possuem aplicações para matar a dor. Além disso, como em casos de dor crônica ou extrema, não é incomum que um indivíduo sofra algum grau de depressão. Os antidepressivos podem desempenhar um duplo papel. Os anticonvulsivantes comummente prescritos para dor incluem fenitoína, carbamazepina e clonazepam. Os antidepressivos tricíclicos incluem doxepina, amitriptilina e imipramina. A dor intratável (implacável) pode ser tratada por injeções diretamente ou perto do nervo que está transmitindo o sinal da dor. Esses blocos de raiz também podem ser úteis para determinar o site da geração de dor. À medida que os mecanismos subjacentes à dor anormal são descobertos, outros medicamentos para a dor estão sendo desenvolvidos. As drogas nem sempre são eficazes no controle da dor. Os métodos cirúrgicos são usados ​​como último recurso se as drogas e os anestésicos locais falharem. O procedimento cirúrgico menos destrutivo envolve a implantação de um dispositivo que emite sinais elétricos. Esses sinais perturbam o nervo e impedem que ele transmita a mensagem da dor. No entanto, esse método pode não controlar completamente a dor e não é usado com freqüência. Outras técnicas cirúrgicas envolvem destruir ou cortar o nervo, mas o uso desta técnica é limitado por efeitos colaterais, incluindo dormência desagradável. Tratamento alternativo Ambos os aspectos físicos e psicológicos da dor podem ser tratados através de tratamento alternativo. Algumas das opções de tratamento mais populares incluem acupressão e acupuntura. Técnicas de massagem, quiropraxia e relaxamento, como ioga. Hipnose e meditação. As terapias à base de plantas estão ganhando maior reconhecimento como opções viáveis, por exemplo, a capsaicina, o componente que faz pimenta caiena picante, é usado em unguentos para aliviar a dor articular associada à artrite. A hidroterapia de contraste também pode ser muito benéfica para o alívio da dor. Os estilos de vida podem ser alterados para incorporar uma dieta mais saudável e um exercício regular. Exercício regular, além de aliviar o estresse. Tem mostrado aumentar as endorfinas, analgésicos produzidos naturalmente no corpo. O tratamento bem sucedido da dor é altamente dependente da resolução bem-sucedida da causa do painx0027s. A dor aguda vai parar quando um ferimento cura ou quando um problema subjacente é tratado com sucesso. Dor crônica e dor anormal são mais difíceis de tratar, e pode levar mais tempo para encontrar uma resolução bem-sucedida. Algumas dificuldades são intratáveis ​​e exigirão medidas extremas para o alívio. Prevenção A dor é geralmente evitável apenas no grau em que a causa da dor é evitável. Por exemplo, procedimentos cirúrgicos aprimorados, como os feitos através de um tubo fino chamado de laparascópio, minimizam a dor pós-operatória. As técnicas de anestesia para cirurgias também melhoram continuamente. Algumas doenças e lesões muitas vezes são inevitáveis. No entanto, a dor de algumas cirurgias e outros procedimentos médicos e a dor contínua são evitáveis ​​através de tratamentos medicamentosos e terapias alternativas. Periódicos x0022Advanças no Gerenciamento da Dor, Novo Foco Facilmente Cuidados Pós-operatórios. x0022 Dispositivos Médicos x0026 Semana de Tecnologia Cirúrgica 26 de setembro de 2004: 260. Finn, Robert. X0022 Mais do que a metade dos pacientes com depressão maior têm dor crônica. x0022 Notícias da prática familiar 15 de outubro de 2004: 38. x0022 Novas diretrizes definidas para um melhor tratamento da dor. x0022 Carta médica no CDC x0026 FDA 5 de setembro de 2004: 95. Organizações American Chronic Pain Associação. P. O. Box 850, Rocklin, CA 95677-0850. (916) 632-0922. X2329members. tripodx223CwiddyACPA. htmlx232A. American Pain Society. 4700 W. Lake Ave. Glenview, IL 60025. (847) 375-4715. Ampainsoc. org. Dor de dor aguda Dor em resposta a lesão ou outro estímulo que se resolve quando a ferida cura ou o estímulo é removido. Dor de dor crônica Dor que dura além do termo de uma lesão ou estímulo doloroso. Também pode se referir a dor de câncer, dor de uma doença crônica ou degenerativa e dor por uma causa não identificada. Neuron mdash Uma célula nervosa. Neurotransmissores mdash Químicos dentro do sistema nervoso que transmitem informações de ou entre células nervosas. Nociceptor mdash Um neurônio que é capaz de sentir a dor. Mentalidade de dor recomendada Dor sentida em um local diferente da localização da parte ferida ou doente do corpo. A dor recomendada é devida ao fato de que os sinais nervosos de várias áreas do corpo podem aumentar a mesma via nervosa que leva à medula espinhal e ao cérebro. Stimulus mdash Um fator capaz de provocar uma resposta num nervo. Um sentimento de sofrimento, sofrimento ou agonia, causado pela estimulação de terminações nervosas especializadas. Seu propósito é principalmente protetor, ele age como um aviso de que os tecidos estão sendo danificados e induz o sofredor a remover ou retirar a fonte. A Associação Norte Americana de Diagnóstico de Enfermagem aceitou dor como um diagnóstico de enfermagem. Definindo-o como um estado em que um indivíduo experimenta e relata um desconforto grave ou uma sensação desconfortável, o relato de dor pode ser tanto pela comunicação verbal direta quanto por descritores codificados. Receptores de dor e estímulos. Todos os receptores para estímulos de dor são terminações nervosas livres de grupos de fibras neurais mielinizadas ou não mielinizadas distribuídas abundantemente nas camadas superficiais da pele e em certos tecidos mais profundos como o periosteio, as superfícies das articulações, as paredes arteriais e a falx e tentorium de A cavidade craniana. A distribuição dos receptores da dor na mucosa gastrointestinal aparentemente é semelhante à da pele assim, a mucosa é bastante sensível à irritação e a outros estímulos dolorosos. Embora o parênquima do fígado e os alvéolos dos pulmões sejam quase inteiramente insensíveis à dor, o fígado e os ductos biliares são extremamente sensíveis, assim como os brônquios e a pleura parietal. Alguns receptores de dor são seletivos em sua resposta aos estímulos, mas a maioria é sensível a mais do que um dos seguintes tipos de excitação: (1) estresse mecânico do trauma (2) extremos de calor e frio e (3) substâncias químicas, como Histamina, íons de potássio, ácidos, prostaglandinas, bradicinina e acetilcolina. Os receptores de dor, ao contrário de outros receptores sensoriais no corpo, não se adaptam ou tornam-se menos sensíveis à estimulação repetida. Sob certas condições, os receptores tornam-se mais sensíveis ao longo de um período de tempo. Isso explica o fato de que, enquanto um estímulo traumático persistir, a pessoa continuará a ter consciência de que ocorrem dano aos tecidos. O corpo é capaz de reconhecer danos nos tecidos porque, quando as células são destruídas, liberam as substâncias químicas anteriormente mencionadas. Essas substâncias podem estimular os receptores da dor ou causar danos diretos às próprias terminações nervosas. A falta de fornecimento de oxigênio aos tecidos também pode produzir dor causando a liberação de produtos químicos do tecido isquêmico. O espasmo muscular é outra causa de dor, provavelmente porque tem o efeito indireto de causar isquemia e estimulação de receptores de dor quimiossensíveis. Transmissão e Reconhecimento de Dor. Quando os receptores de dor superficiais são excitados, os impulsos são transmitidos a partir desses receptores de superfície para sinapses na substância cinzenta (substância gelatinosa) dos chifres dorsais da medula espinhal. Eles então viajam para cima ao longo dos caminhos sensoriais para o tálamo, que é a principal estação de retransmissão sensorial do cérebro. O núcleo dorsomedial do tálamo projeta o córtex pré-frontal do cérebro. A percepção consciente da dor provavelmente ocorre no tálamo e os centros mais baixos a interpretação da qualidade da dor é provavelmente o papel do córtex cerebral. A percepção da dor por um indivíduo é altamente complexa e individualizada, e está sujeita a uma variedade de influências externas e internas. O córtex cerebral está preocupado com a apreciação da dor e sua qualidade, localização, tipo e intensidade, assim, um córtex sensorial intacto é essencial para a percepção da dor. Além das influências neurais que transmitem e modulam a entrada sensorial, a percepção da dor é afetada por respostas psicológicas e culturais aos estímulos relacionados à dor. Uma pessoa pode ignorar a dor no momento de uma lesão aguda ou outra situação muito estressante, quando está em estado de depressão ou quando se sente uma crise emocional. As influências culturais também prevêem a percepção e a resposta aos estímulos dolorosos. A reação a circunstâncias semelhantes pode variar de estoicismo completo para comportamento histriônico. Controle da dor. Existem várias teorias relacionadas ao controle fisiológico da dor, mas nenhuma foi completamente verificada. Um dos mais conhecidos é o de Mellzak e Wall, a teoria do controle do portão, que propôs que os impulsos da dor foram mediados na substância gelatinosa da medula espinhal com os chifres dorsais atuando como ldquogatesrdquo que controlavam a entrada de sinais de dor nas vias de dor central . Além disso, os sinais de dor competiriam com sinais táteis com os dois constantemente equilibrados um contra o outro. Uma vez que esta teoria foi proposta pela primeira vez, os pesquisadores mostraram que o circuito neuronal que a hipótese não é precisamente correto. No entanto, existem sistemas internos que agora se conhecem naturalmente no corpo para controlar e mediar a dor. Um desses sistemas, o sistema opioide, envolve a produção de substâncias de tipo morfílico chamadas encefalinas e endorfinas. Ambos são analgésicos de ocorrência natural encontrados em várias partes do cérebro e medula espinhal que estão preocupados com a percepção da dor e a transmissão de sinais de dor. Os sinais resultantes da estimulação de neurônios na matéria cinzenta do tronco encefálico viajam para baixo para os chifres dorsais da medula espinhal, onde os impulsos de dor recebidos da periferia terminam. Os sinais descendentes bloqueiam ou reduzem significativamente a transmissão de sinais de dor para cima ao longo da medula espinhal para o cérebro onde a dor é percebida pela liberação dessas substâncias. Além do sistema opioide dos cérebros para controlar a transmissão de impulsos de dor ao longo da medula espinhal, existe outro mecanismo para o controle da dor. A estimulação de grandes fibras sensoriais que se estendem a partir dos receptores táteis na pele pode suprimir a transmissão de sinais de dor de fibras nervosas mais finas. É como se as vias nervosas do cérebro pudessem acomodar apenas um tipo de sinal ao mesmo tempo, e quando dois tipos de impulsos chegam simultaneamente aos chifres dorsais, a sensação tátil prevalece sobre a sensação de dor. A descoberta de endorfinas e a inibição da transmissão da dor por sinais táteis forneceu uma explicação científica para a eficácia de técnicas como relaxamento, massagem, aplicação de linimentos e acupuntura no controle de dor e desconforto. Avaliação da dor. A dor é um fenômeno subjetivo que está presente quando a pessoa que a experimenta diz que é. A pessoa que denuncia desconforto ou dor pessoal é a fonte mais confiável de informações sobre sua localização, qualidade, intensidade, início, fatores precipitantes ou agravantes e medidas que trazem alívio. Os sinais objetivos de dor podem ajudar a verificar o que um paciente diz sobre a dor, mas esses dados não são usados ​​para provar ou refutar se está presente. Os sinais fisiológicos de dor moderada e superficial são respostas do sistema nervoso simpático. Eles incluem movimentos respiratórios rápidos, rasos ou protegidos, palidez, diaforese, aumento da freqüência cardíaca, pressão sanguínea elevada, pupilas dilatadas e distensão dos músculos esqueléticos. A dor que é grave ou localizada no fundo das cavidades do corpo atua como um estimulante para os neurônios parassimpáticos e é evidenciada por uma queda na pressão arterial, diminuição do pulso, palidez, náuseas e vômitos, fraqueza e às vezes perda de consciência. Os sinais comportamentais de dor incluem chorar, gemer, brincar na cama, andar de um lado para o outro, deitar-se silenciosamente, mas tenso em uma posição, desenhando os joelhos para cima em direção ao abdômen, esfregando a parte dolorosa e uma expressão facial comprimida ou fazendo uma careta. A pessoa com dor também pode ter dificuldade em se concentrar e lembrar e pode ser totalmente auto-centrada e preocupada com a dor. Os aspectos psicossociais da tolerância à dor e as suas reações são menos facilmente identificáveis ​​e mais complexas do que as respostas fisiológicas. A reação individual à dor está sujeita a uma variedade de influências psicológicas e culturais. Estes incluem experiência anterior com dor, treinamento em relação a como alguém deve responder a dor e desconforto, estado de saúde e a presença de fadiga ou fraqueza física. O grau de atenção e distração de estímulos dolorosos também pode afetar a percepção da intensidade da dor. Uma avaliação completa da dor leva em consideração todos esses fatores psicossociais. Gestão da dor. Entre as medidas empregadas para aliviar a dor, a administração de analgésicos é provavelmente a que é mais frequentemente incompreendida e abusada. Quando um medicamento analgésico foi requisitado, é necessário que haja necessidade de um paciente, por isso o paciente deve saber que o medicamento está realmente disponível quando necessário e que será dado imediatamente quando solicitado. Se o paciente for forçado a esperar até que outra pessoa decida quando um analgésico é necessário, o paciente pode ficar bravo, ressentido e tenso, diminuindo ou negando completamente o efeito desejado do medicamento. Estudos demonstraram que, quando os analgésicos são deixados à cabeceira dos pacientes com câncer de enfermidade terminal a serem tomadas a seu critério, são tomadas menos doses do que quando devem confiar em outra pessoa para disponibilizar o medicamento. Habituação e dependência de analgésicos provavelmente resultam tanto em não usar outras medidas, juntamente com analgésicos para controle de dor como desde analgésicos prescritos quando são ordenados. A analgesia controlada pelo paciente foi usada com segurança e efetividade. Quando os analgésicos não são apropriados ou suficientes ou quando existe um risco real de dependência, existem técnicas não invasivas que podem ser usadas como alternativas ou adjuvantes para a terapia analgésica. A seleção de uma técnica específica para o manejo da dor depende da causa da dor, sua intensidade e duração, seja aguda ou crônica, e se o paciente percebe a técnica como efetiva. As técnicas de distração fornecem um tipo de blindagem sensorial para tornar a pessoa menos consciente do desconforto. A distração pode ser efetiva no alívio de breves períodos de dor aguda, como aquela associada a procedimentos cirúrgicos menores sob anestesia local, desacutebridamento da ferida e punção venosa. Massagem e pressão suave ativam os impulsos de fibra grossa e produzem uma preponderância de sinais táteis para competir com sinais de dor. É interessante que a estimulação das grandes fibras sensoriais que levem dos receptores sensoriais superficiais na pele pode aliviar a dor em um local distante da área sendo esfregado ou estimulado de outra forma. Uma vez que a isquemia e o espasmo muscular podem produzir desconforto, massagem para melhorar a circulação e o reposicionamento freqüente do corpo e dos membros para evitar a estase circulatória e promover o relaxamento muscular pode ser eficaz na prevenção e manejo da dor. As unidades de estimulação nervosa elétrica transcutânea (TENS) aumentam a produção de endorfinas e encefalinas e também podem aliviar a dor. Técnicas de relaxamento específicas podem ajudar a aliviar a tensão física e mental e o estresse e reduzir a dor. Eles têm sido especialmente eficazes na mitigação do desconforto durante o parto e parto, mas podem ser usados ​​em uma variedade de situações. Aprender técnicas adequadas de relaxamento não é fácil para algumas pessoas, mas uma vez que essas técnicas foram dominadas, elas podem ser de grande benefício no gerenciamento da dor crônica em curso. A intensidade da dor também pode ser reduzida estimulando a pele através de aplicações de calor ou frio, pomadas de mentol e linimentos. A estimulação contralateral envolve estimular a pele em uma área do lado oposto a uma região dolorosa. A estimulação pode ser feita esfregando, massageando ou aplicando calor ou frio. Uma vez que a dor é um sintoma e, portanto, de valor no diagnóstico, é importante manter registros precisos das observações do paciente com dor. Essas observações devem incluir o seguinte: a natureza da dor, ou seja, seja descrita pelo paciente como sendo nítida, aborrecida, queimando, doendo, etc. a localização da dor, se o paciente for capaz de determinar isso O tempo de início e a duração, e se certas medidas e medicamentos de enfermagem são ou não bem sucedidos na obtenção de alívio e a relação com outras circunstâncias, como a posição do paciente, ocorrência antes ou depois da ingestão e estímulos no meio ambiente, como o calor Ou frio que pode desencadear o aparecimento da dor. Procedimentos cirúrgicos destinados a aliviar a dor. De Ignatavicius et al. 1999. 1. uma das três categorias de dor estabelecidas pela Associação Internacional para o Estudo da Dor, denotando dor causada por ocorrências como lesões traumáticas, procedimentos cirúrgicos ou distúrbios médicos, os sintomas clínicos geralmente incluem aumento da freqüência cardíaca, pressão arterial E taxa respiratória, respiração superficial, agitação ou inquietação, caras faciais ou fissuras. 2. um diagnóstico de enfermagem aceito pela Associação Norte Americana de Diagnóstico de Enfermagem, definida como uma experiência sensorial e emocional desagradável decorrente de dano tecidual real ou potencial ou descrita em termos de dano, com início repentino ou lento de qualquer intensidade de leve a grave com Um final antecipado ou previsível e uma duração inferior a 6 meses. Dor de dor de inclinação que acompanha as contracções uterinas durante a segunda etapa do trabalho de parto. Dor de câncer, uma das três categorias de dor estabelecidas pela Associação Internacional para o Estudo da Dor, denotando dor associada a malignidades e percebidas pelo paciente individual, existem várias escalas que classificam de 0 a 10 de acordo com o nível de gravidade. 1. uma das três categorias de dor estabelecidas pela Associação Internacional para o Estudo da Dor, denotando dor que é persistente, com duração de mais de seis meses, os sintomas clínicos podem ser os mesmos que para a dor aguda ou pode não haver sintomas evidentes . A Associação Norte Americana de Diagnóstico de Enfermagem aceitou a dor crônica como um diagnóstico de enfermagem. 2. um diagnóstico de enfermagem aceito pela Associação Norte Americana de Diagnóstico de Enfermagem, definida como uma experiência sensorial e emocional desagradável decorrente de dano tecidual real ou potencial ou descrita em termos de dano, com início repentino ou lento de qualquer intensidade de leve a grave, Sem um final antecipado ou previsível, e com uma duração superior a 6 meses. Distúrbio da dor, uma desordem somatoforme caracterizada por uma queixa principal de dor crônica grave que causa dificuldades substanciais ou comprometimento no funcionamento da dor não é fingida nem intencionalmente produzida, e os fatores psicológicos parecem desempenhar um papel importante no início, gravidade, exacerbação ou manutenção . A dor está relacionada a conflitos psicológicos e é agravada pelo estresse ambiental, permite ao paciente evitar uma atividade desagradável ou obter apoio e simpatia. Os pacientes podem visitar muitos prestadores de cuidados de saúde na busca de alívio e podem consumir quantidades excessivas de analgésicos sem qualquer efeito. Eles são difíceis de tratar porque resistem fortemente à idéia de que seus sintomas têm uma origem psicológica. Falhas falsas e ineficazes durante a gravidez que se assemelham a dores de parto, não acompanhadas de dilatação cervical, ver também as contracções de Braxton-Hicks. Chamado também de trabalho falso. Crescendo em qualquer um dos vários tipos de dores de membros recorrentes que se assemelham às de condições reumatóides, vistas no início da juventude e anteriormente pensadas para serem causadas pelo processo de crescimento. Dor de dor de fome chegando no momento de sentir fome de uma refeição um sintoma de transtorno gástrico. Dor de dor intermenstrual que acompanha a ovulação, ocorrendo durante o período entre a menstruação, geralmente a meio caminho. Trabalho ps as dores rítmicas de crescente gravidade e freqüência devido à contração do útero no parto, ver também trabalho. Dor lancinante dores afiadas. Dor de dor fantasma sentiu como se estivesse a surgir em um membro ou órgão ausente ou amputado, veja também amputação. Sintomas de dor psicogênica de dor física com origem psicológica, ver desordem da dor. Referiu dor dolorosa em uma parte diferente daquela em que a causa que a produziu está situada. A dor recomendada geralmente se origina em um dos órgãos viscerais, mas é sentida na pele ou às vezes em outra área no interior do corpo. A dor recomendada provavelmente ocorre porque os sinais de dor das vísceras viajam ao longo das mesmas vias neuronais usadas pelos sinais de dor da pele. A pessoa percebe a dor, mas interpreta-a como tendo originado na pele em vez de em um órgão visceral profundamente arraigado. Área de dor referida, visões anterior e posterior. Descanse uma dor contínua e implacável devido a isquemia da perna, começando por ou sendo agravada por elevação e sendo aliviada sentando com pernas em posição dependente ou em pé. Dor nas raízes causada pela doença das raízes nervosas sensoriais e que ocorre nas áreas cutâneas fornecidas pelas raízes afetadas. 1. Uma sensação variável e desagradável associada ao dano tecidual real ou potencial e mediada por fibras nervosas específicas para o cérebro, onde a sua apreciação consciente pode ser modificada por vários fatores. 2. Termo utilizado para denotar uma contração uterina dolorosa que ocorre no parto. L. poena, uma multa, uma penalidade (px0101n), uma sensação de sofrimento, sofrimento ou agonia, causada pela estimulação de terminações nervosas especializadas. Dor de dor de inclinação que acompanha as contracções uterinas durante a segunda etapa do trabalho de parto. Dores falsas dores ineficazes parecidas com dores de parto, não acompanhadas por dilatação cervical. Dores crescentes de dores quasirreumáticas recorrentes peculiares ao início da juventude. Dor de dor de fome chegando no momento de sentir fome de uma refeição um sintoma de transtorno gástrico. Dor de dor intermenstrual que acompanha a ovulação, ocorrendo durante o período entre a menstruação, geralmente a meio caminho. O trabalho de parto sofre as dores rítmicas de crescente severidade e freqüência devido à contração do útero no parto. phantom limb pain pain felt as though arising in an absent (amputated) limb. psychogenic pain symptoms of physical pain having psychological origin. referred pain pain felt in a part other than that in which the cause that produced it is situated. rest pain a continuous burning pain due to ischemia of the lower leg, which begins or is aggravated after reclining and is relieved by sitting or standing. 1. An unpleasant feeling occurring as a result of injury or disease, usually localized in some part of the body. 2. Mental or emotional suffering distress. 3. One of the uterine contractions occurring in childbirth. Etymology: L, poena, punishment an unpleasant sensation caused by noxious stimulation of the sensory nerve endings. It is a subjective feeling and an individual response to the cause. Pain is a cardinal symptom of inflammation and is valuable in the diagnosis of many disorders and conditions. It may be mild or severe, chronic or acute, lancinating, burning, dull or sharp, precisely or poorly localized, or referred. Experiencing pain is influenced by physical, mental, biochemical, psychological, physiological, social, cultural, and emotional factors. See also acute pain, chronic pain, referred pain. Neurology An unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage-per Intl Assn for Study of Pain a sensation of discomfort, distress, or agony, due to stimulation of specialized nerve endings a sensation of marked discomfort, either sharp and well-localizedndashconducted along A-delta fibers or dull and diffusendashconducted along C nerve fibers. See Acute pain. Acute low back pain. Ankle pain, Back pain. Breakthrough pain. Brief Pain Inventory. Central stroke pain, Chest pain. Chest wall pain. Chronic pain, Discogenic pain. Elbow pain, Gait control theory, Growing pain, Intractable pain. Knee pain, Lightning pain, Low back pain. Noncardiac chest pain, Patient controlled analgesia, Phantom limb pain, Substantial pain. Suprapubic pain. An unpleasant sensation associated with actual or potential tissue damage, and mediated by specific nerve fibers to the brain, where its conscious appreciation may be modified by various factors. L. poena, a fine, a penalty (pan) Fr. peine . fr L. poena . a fine, a penalty, punishment As defined by the International Association for the Study of Pain, an unpleasant sensory and emotional experience arising from actual or potential tissue damage or described in terms of such damage. Pain includes not only the perception of an uncomfortable stimulus but also the response to that perception. About half of those who seek medical help do so because of the primary complaint of pain. Acute pain occurs with an injury or illness is often accompanied by anxiety, diaphoresis, nausea, and vital sign changes such as tachycardia or hypertension and should end after the noxious stimulus is removed or any organ damage heals. Chronic or persistent pain is discomfort that lasts beyond the normal healing period. Pain may arise in nearly any organ system and may have different characteristics in each. Musculoskeletal pain often is exacerbated by movement and may be accompanied by joint swelling or muscle spasm. Myofascial pain is marked by trigger-point tenderness. Visceral pain often is diffuse or vaguely localized, whereas pain from the lining of body cavities often is localized precisely, very intense, and exquisitely sensitive to palpation or movement. Neuropathic (nerve) pain usually stings or burns, or may be described as numbness, tingling, or shooting sensations. Colicky pain fluctuates in intensity from severe to mild, and usually occurs in waves. Referred pain results when an injury or disease occurs in one body part but is felt in another. Several factors influence the experience of pain. Among these are the nature of the injury or illness causing the symptom, the physical and emotional health of the patient, the acuity or chronicity of the symptom, the social milieu andor cultural upbringing of the patient, neurochemistry, memory, personality, and other features. See: table Many clinicians use the mnemonic COLDER to aid the diagnosis of painful diseases. They will ask the patient to describe the C haracter, O nset, L ocation, and D uration of their painful symptoms, as well as the features that E xacerbate or R elieve it. For example: The pain of pleurisy typically is sharp in character, acute in onset, located along the chest wall, and long-lasting it is worsened by deep breathing or coughing and relieved by analgesics or holding still. By contrast, the pain of myocardial ischemia usually is dull or heavy, gradual in onset, and located substernally. It may be worsened by activity (but not by taking a breath or coughing) and relieved by nitroglycerin. In 2000, the Joint Commission on Accreditation of Healthcare Organizations (JCAHO) issued pain-management standards, in 2001 began surveying for compliance, and in 2004 added patient-safety goals, thus most U. S. health care facilities have devised policies and procedures that require pain-intensity rating as a routine part of care (the fifth vital sign). Pain intensity usually is assessed on a numerical scale, in which 0 no pain, 1 to 3 mild pain, 4 to 6 moderate pain, and 7 to 10 severe pain. However, obtaining a numerical rating of pain intensity is possible only if the patient is able to provide this report of the pain being experienced, which infants, children, the critically ill, and cognitively impaired usually are unable to do. The Wong Baker FACES scale, developed for pediatric use, has been used successfully in other patient populations. It uses visual representations of smiles or grimaces to depict the level of pain a patient feels. Patient care Health care professionals must be aware that pain in non-verbal patient can easily be overlooked and must make a conscious effort to ensure that pain in these patients is assessed and treated. Observing subtle behaviors and being sensitive to contextual clues are two pain methods used by health care professionals to try to determine when nonverbal patients are in pain. When this judgment is made, a trial of pain-relieving medication may be used. The responses of the patient and any complications of treatment should be carefully observed and appropriate changes made in dosing or the type of analgesic drug as indicated. Because pain is a subjective and intensely personal problem, sympathetic care is an important part of its relief. In addition to administering analgesic drugs, health care professionals should use a wide range of techniques to help alleviate pain, including local application of cold and heat, tactile stimulation, relaxation techniques, diversion, and active listening, among others. acute pain Pain that typically is produced by sudden injury (e. g. fracture) or illness (e. g. acute infection) and is accompanied by physical signs such as increased heart rate, elevated blood pressure, pupillary dilation, sweating, or hyperventilation. Acute pain is typically sharp in character. It is relayed to the central nervous system rapidly by A delta nerve fibers. Then, at the end of this entry please add the SYN: fast pain Depending on the severity of the underlying stimulus, acute pain may be managed with acetaminophen or anti-inflammatory drugs, immobilization and elevation of the injured body part, or the topical application of heat or ice. Severe acute pain, such as that of broken ribs or of an ischemic part, may require narcotics, often with adjunctive agents like hydroxyzine for relief, or antiemetics. Acute pain should be managed aggressively. Synonym: fast pain adnexal pain Discomfort arising from the fallopian tubes and ovaries usually due to inflammation, infection, or ectopic pregnancy. Pain felt in or along the spine or musculature of the posterior thorax. It is usually characterized by dull, continuous pain and tenderness in the muscles or their attachments in the lower lumbar, lumbosacral, or sacroiliac regions. Back pain is often referred to the leg or legs, following the distribution of the sciatic nerve. Common causes of back pain include pain caused by muscular or tendon strain, herniated intervertebral disk, lumbar spinal stenosis, or spondylolisthesis. Patients with a history of cancer may have back pain caused by metastatic tumors to the vertebrae and should be evaluated to be certain that damage to the spinal cord is not imminent. Patients with back pain and fever (esp. those with a history of injection drug use, tuberculosis, or recent back surgery) should be evaluated for epidural abscess or osteomyelitis. Depending on the underlying cause of the back pain, treatment may include drugs, rest, massage, physical therapy, chiropractic, stretching exercises, injection therapy, and surgery, among others. Most nonmalignant causes of back pain improve with a few days of rest, analgesics, and antiinflammatory drugs, followed by 2 to 4 weeks of anti-inflammatory treatment, appropriate muscle strengthening, and patience. Pain caused by an osteoporotic fracture may prove more debilitating and longer-lasting. Back pain produced by a spinal metastasis can improve with corticosteroids, radiation therapy, intravenous bisphosphonates, andor surgical decompression. Patients with a spinal epidural abscess will need surgical drainage of the infection and antibiotics. Patient care Prolonged bedrest is inadvisable in most patients with back pain. The treatment regimen is explained, implemented, and reinforced. Factors that precipitate symptoms are identified and preventive actions are discussed. bearing-down pains Rectal pressure and discomfort occurring during the second stage of labor, related to fetal descent and the womans straining efforts to expel the fetus. boring pain Piercing, used to describe pain felt deep within the body. breakthrough pain Transient episodes of pain that occur in patients with chronic pain that has been previously reduced to tolerable levels. Breakthrough pain disrupts the well-being of cancer or hospice patients who have been prescribed regular doses of narcotic analgesics. The painful episodes may occur as a previous dose of pain-relieving medication wears off (end-of-dose pain), or after unusual or unanticipated body movements (incident pain). Brodie pain Pain caused near a joint affected with neuralgia when the skin is folded near it. burning pain Pain experienced in heat burns, superficial skin lesions, herpes zoster, and circumscribed neuralgias. causalgic pain central pain Pain due to a lesion in the central nervous system. chest pain Discomfort felt in the upper abdomen, thorax, neck, or shoulders. Chest pain is one of the most common potentially serious complaints offered by patients in emergency departments, hospitals, outpatient settings, and physicians offices. A broad array of diseases and conditions may cause it, including (but not limited to) angina pectoris or myocardial infarction anxiety and hyperventilation aortic dissection costochondritis or injured ribs cough, pneumonia, pleurisy, pneumothorax, or pulmonary emboli esophageal diseases, such as reflux or esophagitis gastritis, duodenitis, or peptic ulcer and stones in the biliary tree. chronic idiopathic pelvic pain Unexplained pelvic pain in a woman that has lasted 6 months or longer. A complete medical, social, and sexual history must be obtained. In an experimental study, women with this illness reported more sexual partners, significantly more spontaneous abortions, and previous nongynecological surgery. These women were more likely to have experienced previous significant psychosexual trauma. The pain associated with CIPP should be treated symptomatically and sympathetically. The participation of pain management specialists, complementary medical providers, and the primary health care provider should be integrated. Realistic goals (e. g. the reduction of pain rather than its elimination) should be set. Medroxyprogesterone acetate, oral contraceptives, presacral neurectomy, hypnosis, and hysterectomy have been tried with varying degrees of success. chronic pain 1. Long-lasting discomfort, with episodic exacerbations, that may be felt in the back, one or more joints, the pelvis, or other parts of the body. 2. Pain that lasts more than 36 months. 3. Pain that lasts more than a month longer than the usual or expected course of an illness. 4. Pain that returns periodically every few weeks or months for many years. Chronic pain is often described by sufferers as being debilitating, intolerable, disabling, or alienating and may occur without an easily identifiable cause. Studies have shown a high correlation between chronic pain and depression or dysphoria, but it is unclear whether the psychological aspects of chronic pain precede or develop as a result of a persons subjective suffering. Chronic pain is the leading cause of disability in the U. S.acute pain Patient care The management of chronic, nonmalignant pain is often difficult and may be frustrating for both sufferer and caregiver. The best results are usually obtained through multimodal therapy that combines sympathetic guidance that encourages patients to recover functional abilities, by combinations of drugs (e. g. nonsteroidal anti-inflammatories, narcotic analgesics, andor antidepressants), physical therapy and regular exercise, occupational therapy, physiatry, psychological or social counseling, and alternative medical therapies (e. g. acupuncture, massage, or relaxation techniques). Placebos, although rarely employed clinically, effectively treat chronic pain in about a third of all patients. Surgery and other invasive strategies are occasionally employed, with variable effectiveness. cramplike pain dental pain Pain in the oral area, which, in general, may be of two origins. Soft tissue pain may be acute or chronic, and a burning pain is due to surface lesions and usually can be discretely localized pulpal pain or tooth pain varies according to whether it is acute or chronic, but it is often difficult to localize. dilating pain Discomfort accompanying rhythmic uterine contractions during the first stage of labor. diskogenic pain Low back pain resulting from degeneration of an intervertebral disk. Discogenic pain differs from neuropathic pain in that it does not radiate into the extremities or torso. A mild discomfort, often difficult to describe, that may be associated with some musculoskeletal injuries or some diseases of the visceral organs. eccentric pain Pain occurring in peripheral structures owing to a lesion involving the posterior roots of the spinal nerves. epigastric pain Pain located between the xiphoid process and the umbilicus. It may suggest a problem in one of many different organs, including the stomach, pancreas, gallbladder, small or large bowel, pleura, or heart. expulsive pains Discomfort during the second stage of labor, associated with bearing-down efforts to expel the fetus. Women may experience a similar pain during delivery of the placenta. false pain Abdominal discomfort associated with Braxton Hicks contractions, which occur during the last trimester of pregnancy. Characteristically, the woman complains of irregular, lower abdominal pains, which are relieved by walking. Vaginal examination shows no change in cervical effacement or dilation. fulgurant pain gallbladder pain Pain in the intestines caused by an accumulation of gas therein. gastralgic pain girdle pain growing pains An imprecise term indicating ill-defined pain, usually in the shin or other areas of the legs, typically occurring after bedtime in children age 5 to 12. There is no evidence that the pain is related to rapid growth or to emotional problems. If these symptoms occur during the daytime, are accompanied by other symptoms, or become progressively more severe, evaluation for infection, cancer, and other diseases of muscle and bone should be undertaken. In the majority of cases, this evaluation is not necessary. The child should be reassured and given acetaminophen or ibuprofen heat and massage can be applied locally. Children with growing pains benefit from concern and reassurance from their parents and health care providers. heterotopic pain homotopic pain Pain felt at the point of injury. hunger pain Pain in the epigastrum that occurs before meals. incident pain Pain due to a sudden, forceful, unanticipated, or unusual body movement or posture. inflammatory pain Pain in the presence of inflammation that is increased by pressure. intermenstrual pain Episodic, localized pelvic discomfort that occurs between menstrual periods, possibly accompanying ovulation. intractable pain Chronic pain that is difficult or impossible to manage with standard interventions. Common causes include metastatic cancer, chronic pancreatitis, radiculopathy, spinal cord transection, or peripheral neuropathy. Intractable pain may also accompany somatoform disorders, depression, fibromyalgia, irritable bowel syndrome, and opiate dependence. Various combinations of the following management strategies are often used to treat intractable pain: antidepressant medications, counseling, deep brain stimulation, injected anesthetics, narcotic analgesics, neurological surgery, and pain clinic consultations. labor pains Uncomfortable, intermittent, rhythmic, girdling sensations associated with uterine contractions during childbearing. The frequency, duration, and intensity of the events increase, climaxing with the delivery of the fetus. lancinating pain lightning pain A sudden brief pain that may be repetitive, usually in the legs but may be at any location. It is associated with tabes dorsalis and other neurological disorders. Synonym: fulgurant pain lingual pain Pain in the tongue that may be due to local lesions, glossitis, fissures, or pernicious anemia. Synonym: tongue pain Sharp pain in the region of the lungs. menstrual pain mental pain Periumbilical and R lower abdomen NOTE: L left R right. An unpleasant or distressing localized sensation caused by stimulation of certain sensory nerve endings called nociceptors, or by strong stimulation of other sensory nerves. Nociceptors are stimulated by the chemical action of substances, such as prostaglandins, released from local cell damaged by injury or inflammation. Whatever the site of nerve stimulation, pain is usually experienced in the region of the nerve endings. Referred pain is pain experienced at a site other than that at which the causal factor is operating. Pain impulses pass to the brain via a series of control x2018gatesx2019 analogous to those in computers and these can be modulated by other nerve impulses. Pain commonly serves as a warning of bodily danger and leads to action to end it. Pain is best treated by discovering and removing the cause. It is a complex phenomenon with many components-somatic, emotional, cognitive and social. The management of acute, self-limiting pain is not the same as long-term pain. The latter requires treatment by a multidisciplinary team in a pain clinic. ANALGESIC drugs can be used to target specific receptors and should not be withheld until pain is severe but given repeatedly in expectation of pain. Pain may be relieved by drugs self-administered on an as-required basis by electrical stimulation of the skin ACUPUNCTURE massage cold sprays LOCAL ANAESTHETIC injections or even, in extreme cases and rarely, by permanent nerve destruction by alcohol injection or by surgical severance. From the Latin poena, punishment. See also ENDORPHINS. an unpleasant, conscious sensation produced in the brain and stimulated by pain receptors in, for example, the skin. Pain has a protective function and often produces a reflex action (see REFLEX ARC in response. the name that we give to the unpleasant and disturbing subjective experience that results from injury or other damage. Sensory receptors involved are known as nociceptors (from the adj noxious meaning harmful) thence afferent nerve impulses reach the central nervous system (CNS), where different influences can diminish or enhance them, acting where they are relayed and transmitted to the cerebral cortex and conscious perception. The pain pathways are separate from those serving other sensations, and even vigorous stimulation of other sensory receptors does not, by itself, cause pain. pain management involves a multdisciplinary approach, often by a specialist team. See also endorphins. transcutaneous electromagnetic nerve stimulation (TENS) . unpleasant sensory and emotional experience associated with, or described in terms of, actual or potential tissue damage, due to a complex interaction of sensory, emotional and behavioural factors pain may be acute or chronic, somatic, visceral or neurogenic it characterizes inflammation phantom-limb pain subjective pain or paraesthesia experienced within an amputated limb referred pain pain perceived as originating from a specific body area although it is remote from the point of pain origin, e. g. heel pain due to S1 nerve lesion n unpleasant emotional or physical sensation, often associated with potential or actual tissue damage and classified as acute, chronic, or cancer-related. See also cancer-related pain . Variably unpleasant sensation associated with tissue damage and mediated by specific nerve fibers to brain where its conscious appreciation is modified. L. poena, a fine, a penalty n an unpleasant sensation created by a noxious stimulus mediated along specific nerve pathways to the central nervous system, where it is interpreted. The sensation of pain is a protective mechanism that warns of danger without giving too much information about the specific nature of the danger. It initiates nociceptive reflexes. pain and suffering , n an element in a claim for damages in a liability lawsuit. It requests compensation to an individual for mental and physical pain and discomfort as a result of an injury. n an evaluation of the reported pain and the factors that alleviate or exacerbate a patients pain used as an aid in the diagnosis and the treatment of disease and trauma. n pain that occurs in the chest region because of disorders of the heart (e. g. angina pectoris, myocardial infarction, or pericarditis), pulmonary artery (pulmonary embolism or hypertension), lungs (pleuritis), esophagus (x201Cheartburnx201D), abdominal organs (aerophagia, biliary tract disease, splenic infarction, or gaseous distention in the splenic flexure), or the chest wall (neoplasia, costochondral strains, trauma, hyperventilation, or muscular tension). n a multidisciplinary association of health care professionals devoted to the diagnosis and treatment of patients with acute and chronic pain. n dull, aching, or boring pain originating in muscles, tendons, and joints. It is poorly localized and tends to radiate. pain dysfunction syndrome , n in dentistry, a phrase used to describe a condition in patients who appear to have a psychophysiologic basis for stress overload on the temporomandibular joint. The preferred term is mandibular stress syndrome . n the network that communicates unpleasant sensations and the perceptions of noxious stimuli throughout the body in association with both physical disease and trauma involving tissue damage. pain, nerve ending , n a receptor nerve ending that is relatively primitive and ends in an undifferentiated arborization. The nerve ending for the sensation of pain is a protective mechanism that warns of danger without giving too much information about the specific nature of the danger. The danger stimuli give rise to nociceptive reflexes, or defensive, protective, or withdrawal movements. The nociceptive reflexes supersede other, less urgent, reflexes that are thus inhibited. pain, projected pathologic , n pain erroneously perceived to arise in a peripheral region because of a stimulus from end-organs supplying the region (e. g. sciatic pain). Actually the stimulus occurred somewhere along the pain pathway from the nerve to the cortex. n the individuals manifestation of the unpleasant sensation. n pain caused by an agent in one area but manifested in another (e. g. pain caused by caries in the maxillary third molar may be referred to the mandible, so the source of pain appears to be in the mandible). n an agent that has the potential to induce pain, whether through chemical, mechanical, or thermal means. pain, tactile stimuli , n any of a number of physical sources that may aggravate dentin hypersensitivity, such as dental instruments, toothbrush bristles, ill-fitting oral prostheses, and various personal oral habits a patient may have. pain, thermal stimuli , n dentin hypersensitivity related to abrupt changes in temperature of teeth as a result of contact with very cold or very hot foods and liquids, rapid intake of air through the oral cavity, and during professional oral hygiene procedures requiring rapid drying of teeth. n the point at which a stimulus causes pain. It varies widely among individuals. n the maximum pain level an individual is able to withstand. a feeling of distress, suffering or agony, caused by stimulation of specialized nerve endings. Its purpose is chiefly protective it acts as a warning that tissues are being damaged and induces the sufferer to remove or withdraw from the source. All receptors for pain stimuli are free nerve endings of groups of myelinated or unmyelinated neural fibers abundantly distributed in the superficial layers of the skin and in certain deeper tissues such as the periosteum, surfaces of the joints, arterial walls, and the falx and tentorium of the cranial cavity. The distribution of pain receptors in the gastrointestinal mucosa apparently is similar to that in the skin thus, the mucosa is quite sensitive to irritation and other painful stimuli. Although the parenchyma of the liver and the alveoli of the lungs are almost entirely insensitive to pain, the liver as an organ and the bile ducts are extremely sensitive, as are the bronchi, ureters, parietal pleura and peritoneum. Some pain receptors are selective in their response to stimuli, but most are sensitive to more than one of the following types of excitation: (1) mechanical stress of trauma (2) extremes of heat and cold and (3) chemical substances, such as histamine, potassium ions, acids, prostaglandins, bradykinin and acetylcholine. The conscious perception of pain probably takes place in the thalamus and lower centers interpretation of the quality of pain is probably the role of the cerebral cortex. There are some naturally occurring internal systems in the body that are known to control pain but none of them has been completely verified. One of the best known is the gate control system in which it is thought that pain impulses are mediated in the substantia gelatinosa of the spinal cord. pain occurring in the area between the thorax and pelvis. Manifestations vary between species. Identifiable syndromes include: (1) horsex2014pawing, flank watching, rolling, straddling as though to urinate, lying on the back (2) cattlex2014may depress back and paddle with hindfeet but mostly arched back, grunting, immobility (3) dogs and catsx2014arched back, grunting, depression, reluctance to move. Sometimes there is elevation of the hindquarters, with the chest and forelegs on the ground (the so-called praying dog attitude). Beagle pain syndrome see beagle pain syndrome. pathology in one area can affect the nerve supply to a distant area in which pain is experienced. free nerve endings of tufts of fine points or buttons. pain felt in an area distant from the site of pathology but not mediated through a common innervation. There is no evidence that referred pain occurs in animals but it seems likely on anatomical grounds. the lowest level at which a stimulus can be applied and cause perceptible pain. the level of stimulation at which pain becomes intolerable. Patient discussion about pain Q. Pulling pain in anus. Dear friends, I am 32. I feel a Pulling pain in anus sometimes while i finish passing stool and some times when i sit for long time. No bleeding so far. Is it a symptoms of piles If so what can be done to cure it without going to doctor or operation. Por favor me ajude. This pain makes me to feel that i am very old. A. horsechestnut is supposed to help. here is some info about it: nccam. nih. govhealthhorsechestnutindex. htmuses but i wouldnt get my hopes high. Q. Polio Syndrome pain One of my aunt is taking Neurontin for Post Polio Syndrome pain in her left leg and arm. she did not realize that she had so much pain and that it was keeping her from doing so many things. Is Neurontin recomended for this treatment and how does it help Will she have problems with Neurontin if she take it long term Neurontin is greatly helping the pain but not the fatique in these limbs. Should it help the fatigue A. Neurontin is being given as medication for nerve pain now also. I take 800 mg a day and it was started for back pain and it is also being used in some fibro patients I am learning( i also have fibromyalgia) It didnt cause me a lot of drowsness but amount of medication and medications affect people differently so each person can be different. But with the fatigue fibromyalgia causes maybe I just cant tell the difference bc before I started it I was tried all the time and that is not any worse. But if your Aunt and yourself feel uncomfortable with this treatment I would suggest a second opinion. Good Luck to your Aunt Q. Why do they think that the pain is all in my head Is there any chance which may wrongfully lead doctor to conclude that our symptoms are of a psychological nature Why do they think that the pain is all in my head A. It may happen very rarely and if he is new to his profession. It doesnt mean that all those are new to their profession does these mistakes. Doctors cannot quotseequot and may not understand the sources of your pain or fatigue. However, what they do observe is your anxiety and frustration with having to deal with these symptoms around-the-clock, which may wrongfully lead them to conclude that your symptoms are of a psychological nature. Also, the old school of thought regarding pain is that it is produced by tissue injury, and there is no obvious source of tissue injury in patients with fibromyalgia. Regardless, if your doctor does not believe that your symptoms are real, you owe it to yourself to find another doctor who believes in you and will work with you to help reduce your symptoms. Link to this page: As when ALCIDES from OEALIA Crownd With conquest, felt th envenomd robe, and tore Through pain up by the roots THESSALIAN Pines, And LICHAS from the top of OETA threw Into th EUBOIC Sea. The little blistering voices of pain that had called out from his scalp were, he thought, definite in their expression of danger. It was necessary that pain should be put forward as a mode of self - realisation. After growing confused from pain while being carried into the hut he again regained consciousness, and while drinking tea once more recalled all that had happened to him, and above all vividly remembered the moment at the ambulance station when, at the sight of the sufferings of a man he disliked, those new thoughts had come to him which promised him happiness. If you have never swallowed it, the pill can not have given you a pain . After all her pains her heroic struggle for freedom had failed. It was a pandemonium of pain. for, their parched throats softened by the water, they were again able to yelp and cry out loudly all their hurt and woe. She had so indescribably touched and interested me, stranger as I was, that the sudden cessation of her faint, sweet tones affected me almost with a sense of pain . She lay so several hours for the drowse deepened into a heavy sleep, and Uncle Alec, still at his post, saw with growing anxiety that a feverish colour began to burn in her cheeks, that her breathing was quick and uneven, and now and then she gave a little moan, as if in pain . When this shower of arrows was over, I fell a-groaning with grief and pain. and then striving again to get loose, they discharged another volley larger than the first, and some of them attempted with spears to stick me in the sides, but, by good luck, I had on a buff jerkin, which they could not pierce. Its burning, searing pain to love her and leave her--but not to have loved her is unthinkable. Or that again which most nearly approaches to the condition of the individual--as in the body, when but a finger of one of us is hurt, the whole frame, drawn towards the soul as a center and forming one kingdom under the ruling power therein, feels the hurt and sympathizes all together with the part affected, and we say that the man has a pain in his finger and the same expression is used about any other part of the body, which has a sensation of pain at suffering or of pleasure at the alleviation of suffering. Salinity Concentration of dissolved salts found in a sample of water. Measured as the total amount of dissolved salts in parts per thousand. Seawater has an average salinity of about 34 parts per thousand. Salinization Pedogenic process that concentrates salts at or near the soil surface because evapotranspiration greatly exceeds water inputs from precipitation . Salt (1) The mineral sodium chloride. (2) Compounds that are produced as the result of a metal atom replacing a hydrogen atom in an acid . Saltation Transport of sediment initiated by moving air or water where particles move from a resting surface to the transport medium in quick continuous repeated cycles. Salt Marsh Coastal wetland ecosystem that is inundated for some period of time by seawater . Plants that exist in this community have special adaptation to survive in the presence of high salinities in their immediate environment. Generally, found poleward of 30deg North and South latitude. Saltwater Intrusion The invasion of saltwater into freshwater aquifers in coastal and inland areas. This condition can be cause when groundwater . which charges the aquifer, is withdrawn faster than it is recharged by precipitation . Sample A sample is a subset group of data selected from a larger population group. Most samples are drawn at random to guaranty equal representation in the data. Sand Mineral particle with a size between 0.06 and 2.0 millimeters in diameter. Also see clay and silt . Sand Dune A hill or ridge of aeolian sand deposits with a minimum height of less than one meter and a maximum height of about 50 meters. Found in hot deserts and along sandy coastlines. Sand Sea A large region of sand and sand dunes in a desert . Common to erg deserts . Sand Sheet Deposit of sometimes stratified less well sorted sand that almost resemble dunes . Common in northern Europe. Believed to form when windblown materials settle on areas of patchy snow. Sandstone A type of sedimentary rock that contains a large quantity of weathered quartz grains. Sand Ripples Another term used for wind ripples . Sand Wedge A form of ice wedge that contains accumulations of wind blown sand in long vertical layers. A form of periglacial ground ice . Santa Ana Wind A warm, dry chinook like wind that occurs in southern California. Originates from the east off an elevated desert plateau. Saturated Adiabatic Lapse Rate ( SALR ) The rate of decline in the temperature of a rising parcel of air after it has reached saturation . This rate is less than the dry adiabatic lapse rate (9.8deg Celsius per 1000 meters) because of the heat energy added to the ascending air parcel from condensation and deposition processes. Saturation Atmospheric condition where water is changing its phase to liquid or solid. At saturation, relative humidity is 100 unless there is a shortage of deposition nuclei or condensation nuclei . Generally, this process is caused by the cooling of the atmosphere. Saturation Mixing Ratio Mass of water vapor that a kilogram of dry air can hold at saturation . Measured in grams. Savanna A tropical or sub-tropical plant community characterized by trees and shrubs scattered among a cover of grasses, herbs and forbs. The climate of a savanna is tropical with a dry season occurring in the low Sun period of the year. Scale A specific relative or proportional size or extent of a phenomena as measured through space andor time . Scarification Extensive movements of soil . Sedimento. and rock material caused by humans. Scattering ( Atmospheric ) Is an atmospheric process where small particles and gas molecules diffuse part of the incoming solar radiation in random directions without any alteration to the wavelength of the electromagnetic energy. Scattering does, however, reduce the amount of incoming radiation reaching the Earths surface. A significant proportion of scattered shortwave solar radiation is redirected back to space. The amount of scattering that takes place is dependent on two factors: wavelength of the incoming radiation and the size of the scattering particle or gas molecule. In the Earths atmosphere, the presence of a large number of particles with a size of about 0.5 microm results in shorter wavelengths being preferentially scattered. This factor also causes our sky to look blue because this color corresponds to those wavelengths that are best diffused . Scavenger Heterotrophic organism that mainly consumes dead animals or the parts of dead animals for food. These organisms do not kill their food. Examples of carnivores include flies, various species of vultures, crabs, and hyenas. Also see herbivore . detritivore. omnivore . and carnivore . Schist A medium to coarse grained metamorphic rock with well developed bedding planes derived from the foliated recrystrallization of platy like minerals like mica . Science Science is a way of acquiring knowledge. To do science, one must follow a specific universal methodology. The central theme in this methodology is the testing of hypotheses and the ability to make predictions. The overall goal of science is to better understand nature and our Universe. Scientific Method The approach science uses to gain knowledge. This method tries to be unbias and neutral. Involves inductive and deductive reasoning, hypothesis testing and falsification . and predictive model testing. Sclerophyllous Vegetation Term used to describe drought resistant vegetation common in Mediterranean climates. Some common adaptations present in this type of vegetation include: deep roots, reduced leaf area exposed to the atmosphere, and waxy thick leaves with closing stomata which resist water loss. Scour (1) Refers to the erosive power of water. (2) Abrasive effects of rocks and sediments incorporated in the ice base of a glacier . Scree An accumulation of weathered rock fragments at the base of a steep rock slope or cliff . Sea (1) A body of saline water found on the Earths continental surface. (2) A portion of a ocean that is in close proximity to a continent. Sea Arch A coastal landform composed of rock that resembles an arch. These landforms are created when waves erode through a thin headland from both sides. Sea Breeze Local thermal circulation pattern found at the interface between land and water. In this circulation system, surface winds blow from water to land during the daytime. Sea-Floor Spreading The process of oceanic crust creation and sea-floor movement that occurs at the mid-oceanic ridge . Sea-Level The average surface elevation of the worlds oceans . Sea-Level Pressure Average atmospheric pressure at sea-level. This value is 1013.2 millibars. Seamount A volcanic mountain found on an ocean basin that has an origin not related to a mid-oceanic ridge or a tectonic subduction zone . Sea Smoke See evaporation fog . Seasons Time periods generally based on the changes in the intensity and duration of sunlight as received in the middle and high latitudes. Four seasons are normally recognized: Spring Summer Fall and Winter . The astronomical definition is more precise and suggests the following time periods for the four seasons: Spring - March 22 to June 21 Summer - June 22 to September 22 Fall - September 23 to December 22 and Winter - December 23 to March 21. Sea Stack A steep pillar of rock located in the ocean a short distance from the coastline . These landforms are created when waves erode through a thin headland from both sides. Seaward Positioned or located away from land but towards an ocean or sea. Seawater The mixture of water and various dissolved salts found in the worlds oceans and seas . Secondary Carnivore See tertiary consumer . Secondary Consumer Organisms that occupy the third trophic level in the grazing food chain . These organisms are carnivores . Also known as a primary carnivore . Secondary Pollutant Atmospheric pollutants that are created chemically in the atmosphere when primary pollutants and other components of the air react. Also see primary pollutant . Secondary Substance Organic chemical produced by a plant that has no direct function in its metabolism . Many of these chemicals are toxic and are believed to be created by the plant to reduce herbivore damage or the negative effects of competition by other plants. Secondary Succession Succession on a previously vegetated surface. The soil or substrate on this location contains an active seed bank . Secondary Wave See S-wave or shear wave . Second-Growth Forest Stand of forest that is the result of secondary succession . Second Law of Thermodynamics This law states that heat can never pass spontaneously from a colder to a hotter body. As a result of this fact, natural processes that involve energy transfer must have one direction, and all natural processes are irreversible. This law also predicts that the entropy of an isolated system always increases with time. Sedge Grass - like plant that is adapted to grow in moist habitats. Sediment Solid material that has been or is being eroded . transported . and deposited . Transport can be due to fluvial . marine, glacial or aeolian agents. Sedimentary Rock Rocks formed by the deposition . alteration andor compression, and lithification of weathered rock debris, chemical precipitates, or organic sediments. Also see clastic vs non-clastic sedimentary rocks. Sediment Rating Curve Numerical expression or graphical curve that describes the quantitative relationship between stream discharge and the sediment transported by a particular stream. Seed Fertilized ovule of a plant that contains an embryo and food products for germination . Once germinated, the embryo can grow into a mature individual. Seed Bank Collection of seeds available for germination in the soil . Seed Dispersal Movement of a plant seed away from the parent plant by a passive or active mechanism. Seepage (1) The gradual movement of water into the soil layer. (2) Slow movement of sub-surface water to the surface. This flow is not great enough to call it a spring . Seepage Lake A lake that gets its water primarily from the seepage of groundwater . Segregated Ice A form of periglacial ground ice that consists of almost pure ice that often exists as an extensive horizontal layer. The ice layer grows because of the active migration of water from around the feature. These features are found just below the active layer . Seif (1) A large sand dune that is elongated in the general direction of the dominant winds. (2) A sand dune formed by winds from multiple directions. Seismic Shaking displacement usually caused by an earthquake . Seismic Wave Successive wave - type displacement of rock usually caused by an earthquake . Seismograph Instrument that measures the energy contained in seismic waves from an earthquake or other type of ground displacement. Seismology A branch of science focused on the study of earthquakes and seismic activity. Self-Regulation The ability of some systems to maintain a steady state equilibrium through positive and negative feedbacks . Semi-Diurnal Tide Tides that have two high and two low waters per tidal period . Sensible Heat Heat that can be measured by a thermometer and thus sensed by humans. Sensible Heat Flux Process where excess heat energy is transferred into the atmosphere. The process first involves the movement of heat energy from the Earths surface to the atmosphere by conduction and convection . The heat energy then can move horizontally advection (atmospheric circulation). One of two days during a year when the declination of the Sun is at the equator. The September equinox denotes the first day of fall in the Northern Hemisphere. In the Southern Hemisphere, this date marks the first day of spring. During the September equinox, all locations on the Earth (except the poles) experience equal (12 hour) day and night. The September equinox occurs on either September 22 or 23. Sexual Reproduction Any process of reproduction that does involve the fusion of gametes . Shale Fine grained sedimentary rock composed of lithified clay particles. Shear Stress Stress caused by forces operating parallel to each other but in opposite directions. Shear Wave A seismic wave that creates wave - like motion perpendicular to the direction of seismic energy propagation. Also called S-wave . Sheet Flow See overland flow . Sheeting A form of physical weathering of rock where surface sheets of material fracture and exfoliate because of pressure release. Also see exfoliation dome . Sheetwash The removal of loose surface materials by overland flow . Process of erosion . Shield A large stable area of exposed very old (more than 600 million years) igneous and metamorphic rock found on continents. This rock forms the nucleus of the continents. Shield Volcano Volcano created from alternate layers of lava flows. Shield volcanoes are slightly sloping having a gradient between 6 and 12deg. Their height can be as high as 9000 meters. The chemistry of the magma of these volcanoes is basaltic . Shore The land area bordering a relatively large water body like a lake or ocean . Shoreline The line that separates a land surface from a water body. Also see coastline . Short Wave A small wave in the polar jet stream and the westerlies that extends from the middle to the upper troposphere . Often associated with the formation of a mid-latitude cyclone at the ground surface. Contrasts with long waves . Shortwave Radiation Electromagnetic radiation with a wavelength between 0.1 and 0.7 micrometers (microm). Commonly used to describe the radiation emitted from the Sun. Shrub A woody plant species that is smaller than a tree . Shrubs usually do not have a trunk. Sial Layer The part of the crust that forms the continents and is composed of relatively light, granitic rocks . Siberian High High pressure system that develops in winter over northern central Asia. Sidereal Day Time it takes to complete one Earth rotation relative to the position of a fixed star. This measurement takes 23 hours, 56 minutes, and 4.09 seconds. Compare with mean solar day . Silica Mineral that is composed of silicon dioxide, SiO 2 . Silicate Group of minerals that have crystal structures based on a silica tetrahedron (SiO 4 ). Silicate Magma Magma that is felsic in composition. Silcretes S edimentary rock created by the chemical precipitation of silica . Sill Horizontal planes of igneous rock that run parallel to the grain of the original rock deposits. They form when magma enters and cools in bedding planes found within the crust. Also see intrusive igneous rock . Silt Mineral particle with a size between 0.004 and 0.06 millimeters in diameter. Also see clay and sand . Siltstone Fine grained sedimentary rock composed of lithified silt particles. Silurian Geologic period that occurred roughly 408 to 438 million years ago. During this period, the first plant and insect species appear. Sima Layer The part of the crust that forms the ocean basins and lower layers in the crust and is composed of relatively heavy, basaltic rocks . Sink (1) Site of the storage of some material. (2) Another name for sinkhole . Sinkhole A pit like hole in found in areas of karst . These features are caused by the weathering of limestone or dolomite by subsurface drainage. Also called a sink or doline . Sinusoidal Equal-Area Projection Map projection that represents areas in their true form on a two-dimensional map. Distances are only correct along parallels and central meridian . Shapes become more distorted away from the central meridian and close to the poles. Slaking See wetting and drying . Slate A fine grained metamorphic rock with well developed bedding planes derived from the slight recrystrallization of shale . Sleet See ice pellets . Sling Psychrometer Psychrometer that uses a rotating handle and a whirling motion to ventilate its wet-bulb thermometer . Slip-Face The lee side of a dune where material accumulates and slides or rolls downslope. Slope Aspect Main compass direction (North, North East, East, South East, South, South West, West, and North West) that a slope faces. Slope Failure The downslope movement of soil and sediment by processes of mass movement . Slump See rotational slip . Small Circle A circle on the globes surface that does not bisect the center of the Earth. Parallels of latitude are examples of small circles. Smog Generic term used to describe mixtures of pollutants in the atmosphere. Also see industrial smog and photochemical smog . Snout Front end of a glacier . Also called the terminus . Snow A type of solid precipitation that forms in clouds with an air temperature below freezing. Snow forms when water vapor deposits directly as a solid on a deposition nuclei . Snowflakes begin their life as very tiny crystals developing on a six-sided hexagonal deposition nuclei . The developing snowflak, then grows fastest at the six points of the nuclei as these surfaces are more exposed to atmospheres water vapor. Snowfall is most common with the frontal lifting associated with mid-latitude cyclones during fall, winter, and spring months when air temperatures are below freezing. Snowfield An area of permanent snow accumulation. Usually at high altitudes or latitudes. Snow Line Altitudinal or latitudinal limit separating zones where snow does not melt during the summer season from areas in which it does. Similar to the concept of firm limit except that it is not limited to glaciers . Snow Melt Conversion of snow into runoff and groundwater flow with the onset of warmer temperatures. Snow Pellets A form of precipitation also known as graupel. Snow pellets are white, spherical bits of ice with a maximum diameter of 5 millimeters. Snow pellets develop when supercooled droplets freeze on snowflakes. Snow pellets often fall for a brief time period when precipitation transforms from ice pellets to snow . Snow pellets can be easily distinguished from packed snowflakes as they tend to bounce when they strike the ground. Packed snowflakes are not dense enough to cause them to bounce. Soil Layer of unconsolidated material found at the Earths surface that has been influenced by the soil forming factors: climate, relief, parent material, time, and organisms. Soil normally consists of weathered mineral particles, dead and living organic matter . air space, and the soil solution . Soil Colloids Very small organic and inorganic particles found in a soil . Inorganic colloids are often clay particles. Soil colloids carry a negative electrical charge and are the primary sites for cation exchange . Soil colloids hold large quantities of elements and compounds which are used by plants for nutrition. Soil Creep Slow mass movement of soil downslope. Occurs where the stresses on the slope material are too small to create a rapid failure. Soil Erosion Transport of soil mineral particles and organic matter by wind, flowing water, or both. Human activities that disturb the soil surface or remove vegetation can enhance this natural process. Soil Fertility The ability of a soil to provide nutrients for plant growth. Soil-Heat Flux The rate of flow of heat energy into, from, or through the soil . Soil Horizon Layer within a soil profile that differs physically, biologically or chemically from layers above andor below it. Soil Moisture Recharge The process of water filling the pore space found in a soil (storage). Soil Organic Matter Organic constituents of soil . Soil Permeability The rate at which water and air move vertically through a soil . Soil Porosity The volume of water that can be held in a soil . Also refers to the ratio of the volume of voids to the total volume of the soil. Soil Profile Vertical arrangement of layers or horizons in a soil . Soil Science The study of soils from an interdisciplinary perspective. Soil Solution Aqueous liquid found within a soil . This liquid normally contains ions released from mineral particles, organic matter or plant roots and leaves. Soil Structure General term that describes how mineral and particles organic matter of are organized and clumped together in a soil . Soil Taxonomy The classification of a soil in a hierarchical system based on its various properties. Grouping goes from general to specific. Soil Texture The relative quantities of the different types and sizes of mineral particles in a soil . Soil Water The water found occupying the pore spaces between soil particles. Solar Altitude Height of the Sun above the horizon from either True North or True South . Solar Constant A term used to describe the average quantity of solar insolation received by a horizontal surface at the edge of the Earths atmosphere . This value is approximately 1370 Watts per square meter. Solar Day Time required for the Earth to complete one rotation relative to the Sun. Solar Energy See insolation . Solar Noon Point of time during the day when the Sun is aligned with True North and True South . Solar Radiation Electromagnetic radiation that originates from the Sun . Most of the Suns radiation is emitted at wavelengths between 1.0 and 0.1 microns (microm). Also see insolation . direct solar radiation . and diffused solar radiation . Solar System The collection of celestial bodies that orbit around the Sun . Solar Wind Mass of ionized gas emitted to space by the Sun . Plays a role in the formation of auroras . Solar Year The time it takes the Earth to make one orbit around the Sun . This is approximately 365.2422 days. Solid A state of matter where molecules where the mass of the substance does not have the property of flow. Solifluction Form of mass movement in environments that experience freeze-thaw action . It is characterized by the slow movement of soil material downslope and the formation of lobe-shaped features. Also see gelifluction . Solonetzic Soil Soil order (type) of the Canadian System of Soil Classification . This soil type is associated with grassland habitats where high levels of evapotranspiration cause the accumulation of salts at or near the soil surface. These soils are common in the dry regions of the prairies where evapotranspiration greatly exceeds precipitation input. Solstice Dates when the declination of the Sun is at 23.5deg North or South of the equator. For the Northern Hemisphere this date falls on June 21 or 22 ( Summer Solstice ). In the Southern Hemisphere the date is December 21 or 22 ( Winter Solstice ). Solum Part of the soil that is capable of supporting life. Solution (1) Form of chemical weathering where rocks and minerals are dissolved by water. Materials entering the mixture can alter the chemical nature of the solution and can increase the strength of this weathering agent. For example, the mixing of carbon dioxide and water can form carbonic acid. (2) The dissolving of a substance into a liquid. Source Region Area where air masses originate and come to possess their moisture and temperature characteristics. Southeast Trade Winds See trade winds . Southern Oscillation Reversal of atmospheric circulation in tropical Pacific Ocean that triggers the development of an El Nio . South Magnetic Pole Location in the Southern Hemisphere where the lines of force from Earths magnetic field are vertical. This point on the Earth gradual changes its position with time. South Pole Surface location defined by the intersection of the polar axis with Earths surface in the Southern Hemisphere. This location has a latitude of 90deg South. Space (1) A distance, area, or volume. (2) An infinite three-dimensional area in which objects have relative coordinates to each other. (3) The region beyond the outer limits of the Earths atmosphere . Spatial Analysis The examination of the spatial pattern of natural and human-made phenomena using numerical analysis and statistics. Spatial Isolation Reproductive isolation of two or more populations of a species by distance or physical barriers. Over long periods of time geographic isolation leads to speciation through divergent evolution because of environmental heterogeneity. Also called geographic isolation . Spatial Tradition Academic tradition in modern Geography that investigates geographic phenomena from a strictly spatial perspective. Specialist Species Species that have a relatively narrow ecological niche . These species may be able to live in only one type of habitat, tolerate only specific environmental conditions, or use only a few types of food. Speciation The process by which new species originate through mutations . natural selection . and evolution . Species (1) The different kinds of organisms found on the Earth as defined by taxonomic andor phylogenic classification. (2) A group of interbreeding organisms that do not ordinarily breed with members of other groups. Species Association A particular grouping of species in an area. Species Diversity Number of different species in a given region. Specific Gravity The ratio of the mass of a body to the mass of an identical volume of water at a specific temperature. Specific Heat Is the heat capacity of a unit mass of a substance or heat needed to raise the temperature of 1 gram (g) of a substance 1 degree Celsius. Specific Humidity Measurement of atmospheric humidity . Specific humidity is the mass of water vapor in a given mass of air. Normally expressed in grams of water vapor per kilogram of air at a specific temperature. Spectrum Is a graph that describes the quantity of radiation that is emitted from a body at particular wavelengths . Speed of Light Velocity of light in a vacuum . This velocity is approximately 3 x 10 8 meters per second. It takes light from the Sun 8 minutes and 20 seconds to reach the Earth. Spheroidal Weathering A type of below ground chemical weathering where the corners of jointed rocks become rounded over time. Rock changes from a rectangular to more round shape. Spit A long and narrow accumulation of sand andor gravel that projects into a body of ocean water. These features form as the result of the deposition of sediments by longshore drift . Spodosols Soil order (type) of the United States Natural Resources Conservation Service Soil Classification System . A spodosol soil has pronounced layers of illuviation characterized by accumulations of iron and aluminum oxides in the B horizon . These soils form in moist, cool climates. Sporadic Permafrost Form of permafrost that exists as small islands of frozen ground in otherwise unfrozen soil and sediments. SPOT ( Centre National dEtudes Spatiales ) Series of satellites developed by the French Space Agency, with the cooperation with Belgium and Sweden for the purpose of remotely monitoring resources on the Earth. The first SPOT satellite was launched in 1986. See the following website for more information - SPOT Image . Spring (1) Season between winter and summer . Astronomically it is the period from the vernal equinox to the summer solstice in the Northern Hemisphere. (2) A natural flow of water from the sub-surface to the surface. Usually occurs when the water table intersects the Earths surface. Spring Tide Tide that occurs every 14 to 15 days and coincides with the new and full moon. This tide has a large tidal range because the gravitational forces of the moon and Sun are complementary to each other. Contrasts with neap tide . Squall Line A band of thunderstorm development found ahead of a cold front . Stability The capability of a system to tolerate or recover from disturbance or an environmental stress. Stable Atmosphere Condition in the atmosphere where isolated air parcels have a tendency to sink. The parcels of air tend to be cooler than the air that surrounds them. Stable Equilibrium In a stable equilibrium the system displays tendencies to return to the same equilibrium after disturbance . Stadial Moraine See recessional moraine . Stage The elevation of the water surface in a stream channel . Standard Atmospheric Pressure A pressure of 101.32 kilopascals or 1013.2 millibars . Standard Deviation A statistical measure of the dispersion of observation values in a data set. Calculated by determining the square root of the variance . Star A large and very massive, self-luminous celestial body of gas that illuminates via the radiation derived from its internal source of energy . Starch Complex carbohydrate composed of thousands of glucose units. Main compound that plants use to store their food energy. State of Matter Form of matter . Matter can exist in three different forms gas . liquid . and solid . Static Equilibrium Static equilibrium occurs where force and reaction are balanced and the properties of the system remain unchanged over time. Stationary Front A transition zone in the atmosphere where there is little movement of opposing air masses and winds blow towards the front from opposite directions. Steady State Equilibrium In this type of equilibrium the average condition of the system remains unchanged over time. Steam Fog See evaporation fog . Stemflow Is the process that directs precipitation down plant branches and stems. The redirection of water by this process causes the ground area around the plants stem to receive additional moisture. The amount of stemflow is determined by leaf shape and stem and branch architecture. In general, deciduous trees have more stemflow than coniferous vegetation. Stefan-Boltzmann Law This radiation law suggests the amount of radiation given off by a body is proportional to the 4th power of its temperature as measured in Kelvin units. This law can be expressed by the following simple equation: E s T 4 where E is the amount of radiation emitted by the body in Watts per square meter, s is a constant equal to 0.0000000567, and T is the temperature of the body in Kelvins . Steppe Russian term for mid-latitude grasslands . Stoma (pl. Stomata ) Small opening on the surface of a plant that is used for gas exchange. Storm Surge Relatively rapid rise in the height of the ocean along a coastline. Often caused by the storm winds pushing water towards land. Storm Track The path taken by a storm ( thunderstorm . mid-latitude cyclone or hurricane ) or the average path taken by storms. Stoss Side of a slope that faces the direction of flow of ice, wind, or water. Opposite of lee . Stratified Drift A type of glacial drift that has been partially sorted by glaciofluvial meltwater. Strata The layers or beds found in sedimentary rock . Stratigraphy Subdiscipline of geology that studies sequence, spacing, composition, and spatial distribution of sedimentary deposits and rocks . Stratocumulus Clouds Low altitude gray colored cloud composed of water droplets that has a patchy appearance. Each cloud patch consists of a rounded mass. This cloud has a somewhat uniform base and normally covers the entire sky. Between the patches blue sky can be seen. Found in an altitude range from the surface to 3,000 meters. Stratopause The stratopause is a relatively thin atmospheric transition layer found between the stratosphere and the mesosphere . The height of this layer is about 50 kilometers above the Earths surface. Stratosphere Atmospheric layer found at an average altitude of 11 to 50 kilometers above the Earths surface. Within the stratosphere exists the ozone layer . Ozone s absorption of ultraviolet sunlight causes air temperature within the stratosphere to increase with altitude. Stratovolcano See composite volcano . Stratus Clouds Low altitude gray colored cloud composed of water droplets. This cloud has a uniform base and normally covers the entire sky. It is also quite thick and can obscure the Sun. Light precipitation is often found falling from it. Found in an altitude range from the surface to 3,000 meters. Stream A long narrow channel of water that flows as a function of gravity and elevation across the Earths surface. Many streams empty into lakes . seas or oceans . Stream Bank Sides of the stream channel . Stream Bed Bottom of the stream channel . Stream Channel Long trough-like depression that is normally occupied by the water in a stream . Stream Discharge A river or streams rate of flow over a particular period of time. Usually measured by a current meter and expressed in cubic meters per second. Stream discharge depends on the volume and velocity of the flow. Stream Flow The flow of water in a river or stream channel . Stream Gradient The change in elevation from a stream s headwaters to its mouth expressed in degrees, percentage, or as a distance ratio (riserun). Stream Load Refers to the material or sediment carried by a stream . In normally consists of three components: bed load (pebbles and sand which move along the stream bed without being permanently suspend in the flowing water), suspended load ( silts and clays in suspension ) and dissolved load (material in solution ). Stream Order The relative position, or rank, of a stream channel segment in a drainage network . Stream Long Profile Vertical and horizontal profile of the stream . Most streams have a profile that is concave shaped. Striations Grooves of scratches found in surface rock that are the result of glacial abrasion . Strike One of the directional properties of a geologic structure such as a fold or a fault . Strike is the horizontal directional taken by an imaginary line drawn on the plane of the formation. Also see dip . Strike-Slip Fault Fault that primarily displays horizontal displacement. Structural Landform Is a landform created by massive Earth movements due to plate tectonics . This includes landforms with some of the following geomorphic features: fold mountains, rift valleys, and volcanoes. Subatomic Particles Extremely small particles that make up the internal structure of atoms . Subduction ( Tectonic ) Process of plate tectonics where one lithospheric plate is pushed below another into the asthenosphere . Subduction Zone Linear area where tectonic subduction takes place. Sublimation Process where ice changes into water vapor without first becoming liquid. This process requires approximately 680 calories of heat energy for each gram of water converted. Submarine Canyon V-shaped canyons cut into the continental slope to a deep of up to 1200 meters. These features are normally associated with major rivers. Subpolar Glacier Glacier in which the ice found from the its surface to base has a temperature as cold as -30deg Celsius throughout the year. This is well below the pressure melting point . However, melting does occur in the accumulation zone in the summer. One of the three types of glaciers: cold glacier temperate glacier and subpolar glacier . Subpolar Lows Surface zone of atmospheric low pressure located at about 60deg North and South latitude. These low pressure systems are produced by the frontal lifting of subtropical air masses over polar air. Subsea Permafrost Form of permafrost that exists beneath the sea in ocean sediments. Subsidence Lowering or sinking of the Earths surface. Subsolar Point The location on the Earth where the Sun is directly overhead. Also see declination . Subtropical High Pressure Zone Surface zone of atmospheric high pressure located at about 30deg North and South latitude. These high pressure systems produced by vertically descending air currents from the Hadley cell . Subtropical Jet Stream Relatively fast uniform winds concentrated within the upper atmosphere in a narrow band. The subtropical jet stream exists in the subtropics at an altitude of approximately 13 kilometers. This jet stream flows from west to east and has a speed that is somewhat slower that the polar jet stream . Also see jet stream . Succession Directional cumulative change in the types plant species that occupy a given area, through time. Succulent Vegetation Group of plants that have the ability to survive in deserts and other dry climates by having no leaves. Instead their branches and stems that are photosynthetic . This adaptation reduces the surface area for evaporation thus reducing the loss of scarce water. Sugar Type of carbohydrate chemically based on carbon, oxygen, and hydrogen. Sulfur Dioxide A gas produced from volcanic eruptions, ocean spray, organic decomposition and the burning of fossil fuels . Sulfur dioxide is a component in the creation of acid precipitation . This colorless gas has the chemical formula SO 2 . Sulfate Aerosol Type of solid compound commonly found in the atmosphere . These particles play an important role in reflecting . absorbing . and scattering incoming insolation . The source of these compounds is both natural and human-made. Most of the human-made particles come from the combustion of fossil fuels . Sulfuric Acid Acid with the chemical formula H 2 SO 4 . Summer Season between spring and fall . Astronomically it is the period from the summer solstice to the autumnal equinox in the Northern Hemisphere. Summer Solstice The summer solstice denotes the first day of the summer season. For the Northern Hemisphere, the date of summer solstice is either on June 21 or 22 (changes yearly). December 21 or 22 is the date of the summer solstice for the Southern Hemisphere. During the summer solstice, locations in their respective hemispheres experience the longest day of the year. Sun Luminous star around which the Earth and other planets revolve around. The Sun emits 63,000,000 Watts per square meter of electromagnetic radiation . The Sun has an average distance from the Earth of about 150,000,000 kilometers. The Earths orbit is not circular but elliptical. Sunrise Moment of time when the Sun s edge first appears above the Earths horizon . Sunset Moment of time when the Sun s edge completely disappears below the Earths horizon . Sunspot Dark colored region on the Sun that represents an area of cooler temperatures and extremely high magnetic fields. Supercooled Water Cooling of water below 0deg Celsius without freezing. Common in clouds where there is a deficiency of condensation nuclei . Super-Saturation Atmospheric condition where saturation occurs at a relative humidity greater than 100 because of a shortage of deposition or condensation nuclei . Surface Heat Flux Process where heat energy is transferred into land and ocean surfaces on the Earth. Much of this transfer takes place when solar radiation absorbed at the land or ocean surface is converted into heat energy. On land surfaces, surface heat is transfered down into the ground by conduction . Heat energy is transfered to greater depths in ocean surfaces because liquids have the ability mix by convection . Heat energy stored in ocean waters can also move quickly over large horizontal distances in a poleward direction through ocean currents . Surface Creep The sliding and rolling movement of soil particles on the Earths surface because of wind . Eolian process of soil particle movement. Surface Tension Tension of a liquid s surface. Due to the forces of attraction between molecules . Surface Wave Type of seismic wave that travels across the Earths surface. These earthquake generated waves cause the Earths surface to roll or sway like waves on the ocean. Surge A large, destructive ocean wave caused by very low atmospheric pressure and strong winds. Hurricanes often cause a surge of the ocean surface. Suspended Load Portion of the stream load that is carried almost permanently suspended in flowing water. Suspension Erosional movement of sediment continually held in the transport medium of air, water or ice. Sustainable Development Forms of economic growth and other human activities that meet the requirements of the present without jeopardizing the ability of future generations of individuals to meet their own needs. Swash A thin sheet of water that moves up the beach face after a wave of water breaks on the shore . S-Wave A seismic wave that moves material it encounters perpendicular to its direction of travel. This type of seismic wave causes shear stress in the material it moves through. Also called a secondary wave or a shear wave . Swell A relatively smooth ocean wave that travels some distance from the area of its generation. Symbiotic Mutual relationship between two organisms which is necessary for either to survive. Symbiotic Mutualism Mutualistic interaction where the species interact physically and their relationship is biologically essential for survival . Syncline A fold in rock layers that forms a trough-like bend. Synoptic Scale Scale of geographic coverage used on daily weather maps to describe large scale atmospheric phenomenon (for example, mid-latitude cyclone . air masses . fronts . and hurricanes ). System A system is a set of interrelated components working together towards some kind of process. System Attribute A system attribute is the perceived characteristic of a system element . For example, number, size, color, volume, and temperature may be some of the perceived characteristics of clouds in the atmospheric system. System Boundary Outer edge of system . Zone between one system and another system. System Element System elements are the kinds of things or substances composing the system . They may be atoms or molecules, or larger bodies of matter-sand grains, rain drops, plants, or cows. System Relationship Is the association that exist between the elements and attributes of a system based on cause and effect. System State Current value of a systems elements . attributes . andor relationships .