Influência da combinação de métodos de aquecimento no intraoperatório na temperatura central em pacientes obesas e não obesas durante anestesia venosa total / The effects of combining intraoperative warming methods on core temperature in obese and non-obese patients during intravenous anesthesia

Introdução e objetivo: O obeso tem menor incidência de hipotermia intraoperatória em relação ao não obeso por apresentar limiar de vasoconstrição termorregulatória mais elevado. A combinação de métodos de aquecimento no intraoperatório parece ser melhor do que o uso isolado na prevenção de hipotermia. O objetivo da pesquisa foi avaliar se a combinação de permutador de calor e umidade (PCU) no circuito inspiratório com ar forçado aquecido ou aquecimento das soluções parenterais previne a ocorrência de hipotermia no período intraoperatório em obesas (OB) e não obesas (NOB) submetidas à anestesia venosa total. Pacientes e Método: Quarenta pacientes submetidas à cirurgia abdominal ginecológica foram anestesiadas com propofol e remifentanil em infusão alvocontrolada. Todas as pacientes tinham um PCU acoplado no circuito inspiratório. As pacientes foram distribuídas aleatoriamente em 4 grupos de acordo com o índice de massa corporal (IMC) e com o manejo termal. Em 10 obesas (IMC de 30 a 34,9 kg.m-2) e 10 não obesas (IMC de 18,5 a 24,9 kg.m-2), utilizou-se ar forçado aquecido nos membros inferiores (WB). Dez obesas e 10 não obesas receberam aquecimento das soluções infundidas (HF). A temperatura central foi registrada nos momentos controle (0) e 15, 30, 60 90 e 120 minutos após instalação do circuito respiratório, e no final da cirurgia. Na Sala de Recuperação Pós-Anestésica (SRPA), a temperatura central das pacientes foi registrada durante o período de 1 hora. O IMC e a temperatura central foram correlacionados nos grupos que receberam o mesmo tratamento termal da hipotermia...

BACKGROUND AND OBJECTIVE: Obese individuals show less intraoperative (IOP) hypothermia than non-obese ones due to higher vasoconstriction threshold. A combination of warming methods may be better than an isolated one in preventing IOP hypothermia. Our aim was to evaluate whether the combination of a heat and moisture exchanger (HME) on inhaled gas with IOP forced air warming blanket (WB) or warming intravenous (IV) fluids (HF) prevents IOP hypothermia in obese (OB) and non-obese (NOB) women under intravenous anesthesia. METHODS: Forty patients scheduled for gynecological abdominal surgery were anesthetized with propofol and remifentanil in a target controlled infusion. All patients had a HME on the inhaled gas. Patients were randomly distributed into 4 groups according to body mass index (BMI) and IOP thermal management. Ten OB grade I (BMI between 30 and 34.9 kg.m-2) and 10 NOB (BMI between 18.5 and 24.9 kg.m-2) had WB on the lower limbs. Ten OB and 10 NOB patients received IV HF. Core temperatures were recorded at baseline, after 15, 30, 60, 90, and 120 minutes of ventilatory system installation, and at the end of surgery. Core temperature was also followed for 60 minutes in the Post Anesthetic Care Unit (PACU). Core temperature and BMI were correlated in the groups with the same hypothermia treatment method...

Mortality in anesthesia: a systematic review

This systematic review of the Brazilian and worldwide literature aims to evaluate the incidence and causes of perioperative and anesthesia-related mortality. Studies were identified by searching the Medline and Scielo databases, followed by a manual search for relevant articles. Our review includes studies published between 1954 and 2007. Each publication was reviewed to identify author(s), study period, data source, perioperative mortality rates, and anesthesia-related mortality rates. Thirty-three trials were assessed. Brazilian and worldwide studies demonstrated a similar decline in anesthesia-related mortality rates, which amounted to fewer than 1 death per 10,000 anesthetics in the past two decades. Perioperative mortality rates also decreased during this period, with fewer than 20 deaths per 10,000 anesthetics in developed countries. Brazilian studies showed higher perioperative mortality rates, from 19 to 51 deaths per 10,000 anesthetics. The majority of perioperative deaths occurred in neonates, children under one year, elderly patients, males, patients of ASA III physical status or poorer, emergency surgeries, during general anesthesia, and cardiac surgery followed by thoracic, vascular, gastroenterologic, pediatric and orthopedic surgeries. The main causes of anesthesia-related mortality were problems with airway management and cardiocirculatory events related to anesthesia and drug administration. Our systematic review of the literature shows that perioperative mortality rates are higher in Brazil than in developed countries, while anesthesia-related mortality rates are similar in Brazil and in developed countries. Most cases of anesthesia-related mortality are associated with cardiocirculatory and airway events. These data may be useful in developing strategies to prevent anesthesia-related deaths.