Perioperative warming with a thermal gown prevents maternal temperature loss during elective cesarean section. A randomized clinical trial / O aquecimento no perioperatório com avental cirúrgico térmico impede a perda de temperatura materna durante a cesariana eletiva. Estudo clínico randômico

Abstract Background and objectives: Decrease in body temperature is common during general and regional anesthesia. Forced-air warming intraoperative during cesarean section under spinal anesthesia seems not able to prevent it. The hypothesis considers that active warming before the intraoperative period avoids temperature loss during cesarean. Methods: Forty healthy pregnant patients undergoing elective cesarean section with spinal anesthesia received active warming from a thermal gown in the preoperative care unit 30 min before spinal anesthesia and during surgery (Go, n = 20), or no active warming at any time (Ct, n = 20). After induction of spinal anesthesia, the thermal gown was replaced over the chest and upper limbs and maintained throughout study. Room temperature, hemoglobin saturation, heart rate, arterial pressure, and tympanic body temperature were registered 30 min before (baseline) spinal anesthesia, right after it (time zero) and every 15 min thereafter. Results: There was no difference for temperature at baseline, but they were significant throughout the study (p < 0.0001; repeated measure ANCOVA). Tympanic temperature baseline was 36.6 ± 0.3 °C, measured 36.5 ± 0.3 °C at time zero and reached 36.1 ± 0.2 °C for gown group, while control group had baseline temperature of 36.4 ± 0.4 °C, measured 36.3 ± 0.3 °C at time zero and reached 35.4 ± 0.4 °C (F = 32.53; 95% CI 0.45-0.86; p < 0.001). Hemodynamics did not differ throughout the study for both groups of patients. Conclusion: Active warming 30 min before spinal anesthesia and during surgery prevented a fall in body temperature in full-term pregnant women during elective cesarean delivery.

Resumo Justificativa e objetivos: A redução da temperatura corporal é comum durante a anestesia tanto geral quanto regional. O sistema de ar forçado aquecido no intraoperatório durante a cesariana sob anestesia peridural não parece conseguir impedi-la. A hipótese considera que o aquecimento ativo antes do período intraoperatório evita a perda de temperatura durante a cesariana. Métodos: Quarenta pacientes grávidas, saudáveis, submetidas à cesariana eletiva com anestesia espinal receberam aquecimento ativo de um avental térmico na unidade de cuidados pré-operatórios 30 minutos antes da anestesia e durante a cirurgia (Go, n = 20) ou nenhum aquecimento ativo a qualquer momento (Ct, n = 20). Após a indução da anestesia espinhal, o avental térmico foi colocado sobre o tórax e os membros superiores e mantido durante o estudo. Temperatura ambiente, saturação de hemoglobina, frequência cardíaca, pressão arterial e temperatura corporal timpânica foram registradas 30 minutos antes (fase basal) da anestesia espinhal, logo após a anestesia (tempo zero) e a cada 15 minutos subsequentemente. Resultados: Não houve diferença de temperatura na fase basal, mas as diferenças foram significativas ao longo do estudo (p < 0,0001; Ancova de medida repetida). A temperatura timpânica na fase basal foi de 36,6 ± 0,3 °C, mediu 36,5 ± 0,3 °C no tempo zero e atingiu 36,1 ± 0,2 °C no grupo avental, enquanto a temperatura basal do grupo controle foi de 36,4 ± 0,4 °C, mediu 36,3 ± 0,3 °C no tempo zero e atingiu 35,4 ± 0,4 °C (F = 32,53; IC de 95% 0,45-0,86, p < 0,001). A hemodinâmica não diferiu ao longo do estudo em ambos os grupos de pacientes. Conclusão: O aquecimento ativo 30 minutos antes da anestesia espinhal e durante a cirurgia evitou a queda da temperatura corporal em mulheres grávidas a termo durante a cesariana eletiva.

Há risco de êmbolos durante a infusão com o uso de aquecedores com linhas de aquecimento de sangue e líquidos? / Is there risk of emboli during Infusion with Line type blood-liquid warmers? / ¿Existen riesgos de émbolos durante la infusión con el uso de calentadores con líneas de calentamiento de sangre y líquidos?

JUSTIFICATIVA E OBJETIVOS: Os aquecedores de sangue e de líquidos que aquecem em linha são amplamente usados por causa do baixo custo, do uso prático e porque não dependem de equipamentos. Nosso objetivo foi investigar a formação de bolhas em dois aquecedores tipo linha com duas formas de aquecimento diferentes. MATERIAIS E MÉTODOS: Dois grupos foram designados às marcas de aquecedores de sangue e líquidos: S-line e Astoflo®. Com o uso de 10 conjuntos de soro para cada grupo (n = 20), 1.000 mL de solução NaCl a 9% foram infundidos a 350 mL.hora-1 durante uma hora na sala de operação. As seguintes temperaturas foram mensuradas: das partes proximal, intermediária e distal das linhas; do ambiente de ensaio; do líquido usado e do líquido ao atingir a cânula após o aquecimento. O tempo para a formação visível de bolhas foi registrado. Os achados foram estatisticamente comparados com o uso do teste-U de Mann-Whitney. RESULTADOS: Não houve diferença entre os grupos em relação às temperaturas proximal, intermediária e distal das partes das linhas; do ambiente do estudo; do líquido usado e do líquido ao atingir a cânula (p > 0,05). Bolhas foram observadas nos dois aquecedores e o tempo para a formação de bolhas foi semelhante nos dois grupos de estudo (p = 0,143). CONCLUSÕES: No cenário experimental, criamos condições semelhantes ao nosso ambiente clínico. Ambos os tipos de aquecedores forneceram níveis de aquecimento semelhantes e formaram bolhas visíveis. Considerando que uma pequena quantidade de êmbolos pode ser fatal em bebês e crianças, a formação de bolhas deve ser seriamente considerada em caso de êmbolos e estudos adicionais devem ser feitos para determinar a quantidade, as razões e os conteúdos da formação de bolhas.

INTRODUCTION: Line type blood-liquid warmers are used widely due to their low expense, practical use and nondependence on sets. We aimed to investigate the relationship of bubbles in line type warmers with two different warming properties. MATERIALS AND METHODS: Two groups were designed with S-line and Astoflo® brand blood-liquid warmers. By using 10 medisets for each group (n = 20), we infused 1,000 mL 0.9% NaCl solutions at 350 mL.hour-1 speed for one hour in the operating room. Temperatures at the proximal, midway and distal parts of lines, temperature of experiment environment, temperature of liquid used and temperature of liquid reaching the cannula after warming were measured. Time to visually observable bubble formation was recorded. We compared findings statistically using the Mann-Whitney U test. RESULTS: There were no differences between the groups with respect to temperatures at the proximal, midway and distal parts of lines, temperature of experiment environment, temperature of liquid used and temperature of liquid reaching the cannula (p > 0.05). Bubbles were observed with both warmers and time to bubble formation was similar in the two study groups (p = 0.143). CONCLUSIONS: In the experimental setting, we have designed conditions similar to our clinical environment. Both types of warmers provided similar warming levels and formed visible bubbles. Considering that low amounts of emboli can be fatal in infants and children, bubble formation should be taken seriously into account for emboli and further studies should be carried out to determine the amount, the reasons and the contents of bubble formation.

JUSTIFICATIVA Y OBJETIVOS: Los calentadores que poseen un calentamiento en línea de sangre y de líquidos son extensamente usados a causa de su bajo coste, del uso práctico y también porque no dependen de equipos. Nuestro objetivo fue investigar la formación de burbujas en dos calentadores de tipo línea con dos formas de calentamiento diferentes. MATERIALES Y M&EACUTE;TODOS: Dos grupos fueron designados a las marcas de calentadores de sangre y líquidos: S-line y Astoflo®. Con el uso de 10 conjuntos de suero para cada grupo (n = 20), 1.000 mL de solución NaCl al 9% se infundieron a 350 mL.hora-1 durante una hora en quirófano. Las siguientes temperaturas fueron mensuradas: de las partes proximal, intermedia y distal de las líneas; del ambiente de ensayo; del líquido usado y del líquido al alcanzar la bránula después del calentamiento. El tiempo para la formación visible de burbujas fue registrado. Los hallazgos fueron estadísticamente comparados con el uso del test-U de Mann-Whitney. RESULTADOS: No hubo diferencias entre los grupos con relación a las temperaturas proximal, intermedia y distal de las partes de las líneas; del ambiente del estudio; del líquido usado y del líquido al alcanzar la bránula (p > 0,05). Burbujas se observaron en los dos calentadores y el tiempo para la formación de burbujas fue similar en los dos grupos de estudio (p = 0,143). CONCLUSIONES: Dentro del escenario experimental, creamos condiciones parecidas a nuestro ambiente clínico. Ambos tipos de calentadores suministraron niveles de calentamiento parecidos y formaron burbujas visibles. Considerando que una pequeña cantidad de émbolos puede ser fatal en bebés y en niños, la formación de burbujas debe ser seriamente considerada en caso de émbolos y estudios adicionales deben ser realizados para determinar la cantidad, las razones y los contenidos de la formación de burbujas.

Effect of three different methods in rewarming hypothermic postoperative patients

Hypothermia refers to core body temperature less than 36°C. It was reported that 60 to 80% of all postoperative patients suffered from hypothermia. Hypothermia has a profound effect on every body system and may result in life threatening problems if not recognized and treated promptly. The nurse has an important role in rewarming surgical patients immediately postoperatively. Many researchers found that there are different methods to warm surgical patients immediately postoperatively as radiation using infrared lamps, forced air warmer, and warmed blanket. Comparing between three different nursing methods in rewarming patients after major abdominal surgery. The study was carried out in surgical wards and recovery rooms at Alexandria Main University Hospital. A convenient sample of 60 adult patients was selected and assigned randomly to one of three experimental warming methods. Group I was assigned to extrablanket, group II was assigned to radiation, and group III was assigned to forced air warmer. In postoperative period, all patients in the three different groups were assessed every 5 minutes for core body temperature using tympanic thermometer until return to baseline temperature. The study revealed that the patients warmed with forced air warmer returned to baseline temperature in a shorter period than those who were warmed by the use of radiation or extrablanket. Statistically significant difference was found between the three groups. Rewarming is a priority in the immediate care of postoperative surgical patients because hypothermia may augment the risk of adverse outcome. Therefore, the importance of the use of forced air warmer, radiation using infrared heat lamps, or extrablanket should be emphasized in the postoperative period

Experimental studies on the treatment of frostbite in rats.

The effect of treatment by high dose of vitamin C, rapid rewarming by 37 degrees C water alone and with vitamin C, rapid rewarming by 37 degrees C decoction of Indian black tea alone and with vitamin C for experimentally produced frostbite was evaluated in 6 groups (25 each) of rats. Frostbite was produced experimentally in the hind limbs by exposing the animals at -15 degrees C for 1h using the harness technique. The degree of injury was assessed and classified on the basis of tissue necrosis at the end of 15 days. Administration of high dose of vitamin C for prolonged period and rapid rewarming at 37 degrees C water bath immediately after cold exposure apparently reduced the tissue damage. High dose of vitamin C therapy preceded by rapid rewarming in plain water showed additional benefit. Rapid rewarming in decoction of Indian tea resulted in identical beneficial effect. The degree of tissue preservation was highest with rapid rewarming in tea decoction followed by high dose of vitamin C.