Publicación a texto completo no autorizada por el autor / El documento digital no refiere asesor / Determina el nivel de satisfacción de las pacientes con la analgesia epidural para el control del dolor del trabajo de parto. Estudio de tipo descriptivo, observacional y transversal, en el Hospital Nacional Dos de Mayo, entre marzo y mayo del 2012. Se estudia a 40 pacientes obstétricas para conocer el nivel de satisfacción de la analgesia epidural para el control del dolor del trabajo de parto. Se estima las frecuencias absolutas y relativas para las variables cualitativas y las medidas de tendencia central y de dispersión para las variables cuantitativas. Entre las características clínicas de las pacientes con analgesia epidural que participan en el presente estudio, tienen como edad promedio 21.5±5.1 años, donde se observa que el 35% son gestantes adolescentes. Asimismo, el 77.5% en su mayoría son primigesta. Además, el 65% de gestantes tienen sobrepeso y el 89.5% tiene anemia leve o moderada. Respecto a las características de la práctica de la analgesia epidural en trabajo en parto el 78.9% de las gestantes con analgesia epidural tienen un buen pujo, siendo el 86.9% mayores a 39 semanas, la mayoría de los RN son de sexo masculino (73.7%) con Apgar normal al minuto de 92.5% y a los 5 minutos normal en todos los pacientes. La cesárea es necesaria en dos casos. Sobre el nivel de insatisfacción respecto al dolor antes de la analgesia epidural es “Severo” para todas las pacientes (100%), pero después de la analgesia sólo el 35% de pacientes menciono haber tenido un dolor “Leve” o “Moderado”, inclusive el 100% recomendaría el procedimiento y además lo volvería a aceptar. En resumen, las gestantes mencionan que el nivel de satisfacción es “Bueno” (97.5%) con la analgesia epidural, solo un caso califica de regular su satisfacción (2.5%). Adicionalmente se obtiene alguna información comparando el nivel de satisfacción según gestación: solo las primigestas califican como regular el nivel de satisfacción (2.5%) y respecto a la calificación del dolor después de la analgesia el 25% menciona como “Leve” y 5% como Moderado. Concluye que la mayoría de las gestantes califica de “Buen” nivel de satisfacción de la analgesia epidural. Además todas las gestantes recomendarían el procedimiento y en un parto posterior, opinan que también lo volverían a utilizar. / Trabajo académico

Orientador: Stelio Pacca Loureiro Luna / Resumo: A vantagem da anestesia injetável é a facilidade de produzir os componentes da anestesia (inconsciência, analgesia, relaxamento muscular e proteção neurovegetativa) com doses definidas dos diversos fármacos. Existem controvérsias sobre as doses de propofol necessárias para prover analgesia para realização de cirurgias. Objetivaram-se definir as taxas mínimas de infusão do propofol isoladamente e em associação com a lidocaína para anestesia intravenosa em cães, e a possível potencialização analgésica da lidocaína, avaliando-se os efeitos cardiovasculares e grau de hipnose. As DE50 do propofol e propofol associado a lidocaína foram calculadas em 10 cães (12,85 l 1,22 kg), sem raça definida, anestesiados 2 vezes com intervalo de 15 dias. G1: indução anestésica com propofol (6 mg/kg/iv) e manutenção inicial na velocidade de 0,7 mg/kg/min. G2: indução anestésica com propofol (6 mg/kg) e lidocaína (1,5 mg/kg) e manutenção inicial com propofol (0,7 mg/kg/min) e lidocaína em velocidade constante (0,25 mg/kg/min). A analgesia foi avaliada através do pinçamento de membrana interdigital dos membros posteriores e da ponta da cauda por 15 (quinze) segundos. De acordo com a resposta, a velocidade foi aumentada ou diminuída em 0,05 mg/kg/min, verificando-se a analgesia 10 (dez) minutos após até a determinação da velocidade na qual não havia respostas aos dois estímulos. Esta velocidade foi mantida por mais 2 (duas) mensurações. Em não havendo resposta era considerada a DE50. A média entre as velocidades (com e sem resposta) foi utilizada na determinação da taxa de infusão mínima de cada grupo. Esta DE50 foi utilizada na 2o etapa. Doze cães (12,28 l 1,37 kg) foram divididos em 2 grupos de seis. G3: indução anestésica com 6 mg/kg de propofol e manutenção... (Resumo completo clicar acesso eletrônico abaixo) / Abstract: There is a controversy on the doses of propofol to produce sufficient surgical analgesia. This study aimed to define the minimum infusion rate of propofol and propofol combined to lidocaine for IV anesthesia in dogs. The ED50 of propofol and propofol combined with lidocaine was calculated in 10 dogs, weighing 12.85 l 1.22 kg, anesthetized twice with a interval of 15 days. Anesthesia was induced (6 mg/kg/iv) and maintained with propofol (0.7 mg/kg/min.) (G1) and induced with propofol (6 mg/kg) and lidocaine (1.5 mg/kg) and maintained with propofol (0.7 mg/kg/min) and lidocaine (0.25 mg/kg/min) (G2). Analgesia was investigated by tail clamping and podal reflex. The infusion rate was increased or reduced in 0.05 mg/kg/min, until no painful response was observed. The infusion rate was maintained for more 2 (two) evaluations, with a 10 minutes interval and this rate was considered the DE50 of propofol. The mean infusion rate between no pain response and positive response was considered the mean minimal infusion rate and was used in the second part of the study. Other 12 dogs (12.28 l 1.37 kg) were divided in 2 groups of 6 animals. G3 was treated with the same protocol as G1 and G4 as G2, with the propofol infusion rates previously calculated. Anesthesia was maintained for 2 hours. Hemodynamic and respiratory variables as well as BIS and temperature were measured during anesthesia. There was a smaller cardiovascular depression and greater vascular resistance and acidosis in animals treated with propofol and lidocaine. The BIS was maintained between 40 and 60 in both groups. Lidocaine potentiated in 21% the analgesia produced by propofol. The minimum infusion rate of propofol was 1.25 mg/kg/min when used alone and 0.985 mg/kg/min when combined to lidocaine. Lidocaine potentiated hypnosis and analgesia produced by propofol and minimized the cardiovascular depression, increasing recovery. / Mestre

Assegurar o bem-estar dos animais de laboratório e evitar a dor e o sofrimento desnecessários são as principais considerações na experimentação. Por isso, a investigação em busca de novos protocolos anestésicos que garantam um mínimo ou nulo desconforto dos animais tem-se convertido num tema prioritário. Neste estudo realizou-se a comparação do efeito da combinação de xilazina (X) e ketamina (K) com acepromazina (A) e opióides [metadona (Me), morfina (Mo) e tramadol (T)] com a finalidade de avaliar sua influência nos parâmetros fisiológicos de ratos de laboratório, para ambos os sexos, bem como seu poder analgésico e o efeito da oxigenação sobre os mesmos. A associação XKA para ratos machos e fêmeas e a associação XKMe para fêmeas foram as mais seguras e eficazes para procedimentos anestésicos. Porém, os resultados do teste de formalina com a medição da vocalização ultrassônica (VUS) sugerem que o protocolo de XKA tem um poder analgésico baixo, não sendo indicado para procedimentos que possam gerar dor moderada ou severa. Todas as associações anestésicas tiveram efeitos importantes como diurese, manutenção dos olhos abertos e hiperglicemia, os quais devem ser considerados quando possam influenciar nos resultados experimentais. Também, se conseguiu demonstrar que a oxigenação melhora a saturação de oxigênio (SO2) e os valores da pressão parcial de oxigênio (pO2) confirmando que sua utilização deveria ser sempre parte dos procedimentos experimentais com anestesia injetável para evitar a hipoxemia. Não obstante, observou-se uma acidose respiratória por aumento da pressão parcial do CO2 (pCO2) e diminuição do pH, cuja causa se relacionou à hipoventilação por depressão respiratória e acúmulo de CO2 durante o transcorrer da anestesia. Tal situação demonstra a necessidade de oxigenar os animais desde a indução da anestesia e de administrar medicamentos para reverter a depressão respiratória como a naloxona, bem como utilizar animais que não apresentem nenhum tipo de comprometimento respiratório. Portanto, a inclusão de analgesia e a oxigenação nos protocolos anestésicos injetáveis devem ser utilizadas de forma rotineira garantindo a mínima presença de dor e, com isso, resultados mais confiáveis nos procedimentos experimentais. / Ensuring the wellbeing of laboratory animals and avoiding unnecessary pain and suffering is one of the main considerations in experimentation. Therefore, the investigation of new anesthetic protocols that guarantee a minimum or null discomfort of the animals has become a priority theme. In this study, it was made an evaluation of the effect of the combination of xylazine (X) and ketamine (K) with acepromazina (A) and opioids [methadone (Me), morphine (Mo) e tramadol (T)] with the purpose of comparing their influence on the physiological parameters of laboratory rats, for both sexes, and evaluating their analgesic power and the effect of the oxygenation on them. The XKA protocol for male and females rats and the XKMe protocol for females were the safest and most effective for anesthetic procedures. However, the results of the formalin test with the measurement of the ultrasonic vocalization (VUS) suggest that the XKA protocol had a low analgesic power, and it is not indicated for procedures that can generate moderate or severe pain. All anesthetic protocols had important effects as diuresis, maintenance of open eyes, and hyperglycemia; these effects should be considered when they could influence in the experimental results. It was demonstrated that oxygenation improves oxygen saturation (SO2) and oxygen partial pressure (pO2) confirming that its use should be considered in the experimental procedures with injectable anesthesia to avoid hypoxemia. Nevertheless, a respiratory acidosis was observed due to the increase in partial pressure of CO2 (pCO2) and the decrease in pH, that could be caused for the hypoventilation due to respiratory depression and CO2 accumulation during the course of anesthesia. This leads to consider the need to pre-oxygenate animals from induction, to use drugs to reverse respiratory depression such as naloxone, and to work with animals that are not respiratory compromised. Therefore the inclusion of analgesia and oxygenation in anesthesia protocols should begin to be used routinely ensuring minimal presence of pain and thus more reliable results in the experimental procedures.

Placebo treatments are inert but are known to alleviate symptoms across numerous clinical conditions. One of the most studied placebo effects is placebo analgesia, which is a placebo effect limited to pain relief. This thesis aims to introduce the current state of research regarding the neuroscience of placebo analgesia and specifically to present research findings regarding the neurotransmission. Studies have demonstrated that placebo analgesia can be elicited through two separate processes interacting with each other; manipulation of expectations and through conditioning. These processes seem to affect neurotransmission in different ways. Many brain areas have been found to be correlated to placebo analgesia. Besides the pain-processing brain areas, studies point to that the prefrontal cortex can have a vital role in the placebo analgesic effect. Known neurotransmitters that have shown to be involved in placebo analgesia are endogenous opioids, cholecystokinin (CCK), and endocannabinoids. Studies point to that endogenous opioids are involved in the placebo analgesic effect when elicited by expectation or conditioned by an opioid drug. CCK act on placebo analgesia by affecting the release of endogenous opioids and endocannabinoids seem to be involved in placebo analgesia while it occurs due to conditioning with non-opioid drugs. Getting a better understanding of placebo analgesia and find ways to apply this knowledge in the clinical context could powerfully develop the whole medical society.

Fatal and non-fatal opioid overdoses resulting from opioid induced respiratory depression are a significant problem throughout the world. Whilst the opioid receptor antagonist, naloxone hydrochloride, can effectively reverse opioid overdoses, its use is limited because of the adverse effects it produces. These include severe withdrawal and the reversal of analgesia produced by opioid receptor agonists. In this project, the peripherally acting opioid receptor antagonist, naloxone methiodide, was investigated for its potential to reverse opioid induced respiratory depression without altering centrally mediated effects, such as withdrawal. In the publications presented in this thesis, naloxone hydrochloride and naloxone methiodide were shown to effectively reverse the decreases in respiratory rate produced by the administration of morphine, methadone and heroin in mice. Naloxone hydrochloride and naloxone methiodide also reversed the analgesia produced by these opioid receptor agonist treatments, but only naloxone hydrochloride induced significant withdrawal. The doses of naloxone methiodide required to produce the effects described above were higher than the naloxone hydrochloride doses required. Radioligand binding techniques indicated that this was due to a difference in the affinity of naloxone hydrochloride and naloxone methiodide for µ, δ and κ opioid receptor binding sites. Radioligand binding techniques were also used to confirm that naloxone methiodide, or its metabolites, could not readily cross the blood brain barrier. Therefore, the effects of naloxone methiodide appear to be mediated outside the central nervous system. The final publication aimed to extend our knowledge of opioid induced respiratory depression by utilising new radiotelemetry technology to test the efficacy of naloxone methiodide in rats subjected to a chronic opioid administration regime. This experiment showed that circadian rhythm plays a role in the development of tolerance to the cardiorespiratory effects of continuous and chronic methadone administration, and that naloxone hydrochloride and naloxone methiodide treatment can increase respiratory rate and heart rate after this methadone administration. Therefore, naloxone methiodide can effectively antagonise the peripheral effects produced by opioid receptor agonists. Peripherally acting opioid receptor antagonists should be developed in the future to prevent or treat the adverse effects of opioid receptor agonists. / Thesis (Ph.D.)--Department of Clinical and Experimental Pharmacology, 2004.

Sleep disruption has been implicated in morbidity after major surgery since 1974. Sleep-related upper airway obstruction has been associated with death after upper airway surgery and profound episodic hypoxaemia in the early postoperative period. There is also evidence for a rebound in rapid eye movement (REM) sleep that might be contributing to an increase in episodic sleep-related hypoxaemic events later in the first postoperative week. Speculation regarding the role of REM sleep rebound in the generation of late postoperative morbidity and mortality has evolved into dogma without any direct evidence to support it. The research presented in this thesis involved two main areas: a search for evidence of a clinically important contribution of REM sleep rebound to postoperative morbidity, and a re-examination of the role of sleep in the causation of postoperative episodic hypoxaemic events. To assess the latter, a relationship between airway obstruction under anaesthesia and the severity of sleep-disordered breathing was sought. In 148 consecutive sleep clinic patients, 49% of those with sleep-disordered breathing (SDB) had a number of events in non-rapid eye movement sleep (NREM) that was greater than or equal to that in REM and 51% had saturation nadirs in NREM that were equal to or worse than their nadirs in REM. This suggests SDB is not a REM-predominant phenomenon for most patients. Of 1338 postoperative deaths occurring over 6.5 years in one hospital only 37 were unexpected, most of which were one or two days after surgery with no circadian variation in the time of death, casting further doubt on the potential role of REM rebound. Five of nine subjects studied preoperatively had moderately severe SDB. Unrecognised and significant SDB is common in middle-aged and elderly patients presenting for surgery suggesting overall perioperative risk of important adverse events from SDB is probably small. In 17 postoperative patients, sleep macro-architecture was variably altered with decreases in REM and slow wave sleep while stage 1 sleep and a state of pre-sleep onset drowsiness, both associated with marked ventilatory instability, were increased. Sleep micro-architecture was also changed with an increase in power in the alpha-beta electroencephalogram range. These micro-architectural changes result in ambiguity in the staging of postoperative sleep that may have affected the findings of this and other studies. Twenty-four subjects with airway management difficulty under anaesthesia were all found to have some degree of SDB. Those with the most obstruction-prone airways while anaesthetised had a very high incidence of severe SDB. Such patients warrant referral to a sleep clinic.

<p><strong>Background:</strong> Pain may involve physical, emotional and psychological reactions. Chronic pain can lead to restrictions and problems in everyday life. One of the most common pain states is low back pain. A form of treatment that has been marketed as a charitable and pain reliefing alternative is the Shakti mat. Currently there are no studies on its effects published. <strong>Purpose:</strong> To see whether treatment with Shakti mat in a person with low back pain has an effect on the experience of the ability in activities of daily life and to see if the psychological factors will change. <strong>Method:</strong> The participant had to lie on a Shakti mat once a day for four weeks. The participant was asked to complete five questionnaires two weeks before, during intervention and two weeks after treatment. The Tampa Scale: a Measure of Kinesiophobia measures to what degree the participant experiencing pain for movement or to harm itself in motion, Coping Strategies Questionnaire - Catastrophizing scale investigating catastrophizing thoughts in connection with pain perception, Pain Disability Index investigates how the participants’ everyday affected/hampered by pain, Self-Efficacy Scale investigates how sure the participant is in his ability to carry out a task despite pain and a Self-monitoring diary where the perception of its ability in everyday activities, experience after treatment, the type of underlay and if the participant could lie longer on the Shakti mat were judged. <strong>Results:</strong> The participant’s pain in some everyday activities mitigated while the degree of ability in these increased after four weeks of treatment. The psychological factors had not changed much.</p>

Invasive procedures are often painful and distressing for children and disturbing for their parents. The purpose of this study was to develop a substantive theory of parental perceptions of their school-aged child's responses to an outpatient minor surgical procedure with nitrous oxide. The sample included 22 parents of 21 children who underwent a nitrous procedure. Participants were recruited from the pediatric surgery department at a children's hospital. Semi-structured, audio-recorded interviews were conducted with each participant. Grounded theory method was used to simultaneously collect and analyze the data using the constant comparative method. The findings of the study revealed parental impressions involving a process of various emotions and behaviors. The identified process began at procedural scheduling, progressing through the procedure, and terminated going home. The core category derived from the data was Weathering the Storm before the Calm by Securing Connections. This core category describes the complexity of parental impressions and all categories subsumed by the core category. Six major categories and seven subcategories derived from the data represent parental impressions. Parental feelings of anxiety and fear arose during initial phases of the process. Parents attempted to deal with these stormy feelings in several ways. Parents experienced a sense of calmness after the procedure upon realizing their child was safe. The theme that weaves through the entire process is the parental-child connection and parental presence during the nitrous procedure. Parents also identified barriers and facilitators they faced during this process. The substantive theory that emerged provides nurses with an understanding of the stormy and subsequent calm phases parents endured. This information offers clinicians unique interventions to help parents get through this process. Future research needs extension to other settings such as radiology and other specialties such as plastic surgery and urology. Further research warrants investigating children's perceptions to their procedure with nitrous oxide.

Labor may perhaps be the most painful a woman might experience, although characterized by large inter-individual variability. The perceived pain during labor is the result of diverse factors, i.e. her previous pain experiences, the analgesia she receives and maybe also her genes. The overall aim of this thesis was to investigate biological and psychological mechanisms underlying inter-individual differences in labor pain related behaviors. The mechanisms that characterize endogenous pain relief during labor are not fully understood, though it is known to be partly explained by the effects of β-endorphin (BE). BE plasma levels were followed longitudinally in a cohort of pregnant women and were found to remain unchanged between early and late pregnancy, although with a nadir in the beginning of the third trimester. Furthermore, women with low levels of BE in plasma at the end of the third trimester, required second line labor analgesia to a significantly higher extent than women with normal levels. In a population-based sample of 814 pregnant women we investigated if inter-individual differences in labor pain related behavior was influenced by the pain-protective single nucleotide polymorphism (SNP) combination of guanosine triphosphate cyclohydrolase (GCH1) and the opioid receptor µ-1 gene (OPRM1) A118G SNP. We identified a possible association between the pain-protective SNP combination of GCH1 and use of second line analgesia. No association was found between the OPRM1 and use of analgesia or labor pain related behavior. The association between self-rated antenatal depressed mood and anxiety in relation to pain behaviors and self-reported pain during labor was investigated. We found that depressed mood during pregnancy is associated with early arrival to the delivery department, whereas antenatal anxiety is associated with increased self-rated pain prior to labor analgesia.  In conclusion, although an increasing number of studies strongly suggest that genetic predisposition plays an important role in pain and pain-related mechanisms, GCH1 and OPRM1 has little to offer in terms of individual counseling on labor analgesia. To enable the future use of genetic variability for pre-labor testing and counseling, a number of different genes reflecting pain mediation pathways, involving biological and psychological mechanisms, need to be analyzed in combination.

How is the brain capable of mediating pain relief via the mind alone? Placebo analgesia is just such a case, wherein an inert substance yields relief from a number of pain inducing stimuli. Scholars typically separate several factors thought to contribute to the placebo effect into psychological and neurobiological influences. Psychological mechanisms include expectation and conditioning of analgesic effects, while neurobiological mechanisms implicate the opioidergic descending pain system. The current paper proposes an integrative model in which the rostral anterior cingulate cortex (rACC), implicated in cognitive-affective modulation, receives goal-directed input (i.e., expected pain relief) from the prefrontal cortex. As the rACC processes the cognitive difference between expected and actual pain, it recruits a critical descending pain pathway by means of modulating the periaqueductal gray area (PAG). The PAG is a key relay station that connects to other endogenous subsystems of opioidergic pain relief. Whether the rACC and its connection to the PAG are necessary for the placebo effect is a question future research will have to address.