Hypothermia during herniorrhaphy using local anesthesia with sedation

Abstract

General, spinal and epidural anesthesia disrupt the thermoregulatory response. The resultant decrease in core temperature places increased demands on the cardiovascular system. Virtually all of our groin hernia repairs are performed using local anesthesia. The study was designed to ascertain the impact of local anesthesia with intravenous sedation on thermo-regulation and to evaluate the efficacy of perioperative warming in these cases. Tympanic membrane temperatures were monitored in 50 consecutive inguinal herniorrhaphies performed under local anesthesia with intravenous sedation. The first group (n = 45) were not warmed. An upper body warming cover was applied in the last five cases. In the non-warmed group, a decrease in body temperature of −0.81 °C ± 0.38 was recorded. In the five warmed cases, the change in body temperature was −0.12 °C ± 0.18 °C. The results indicate that the hypothermic response during hernia repair under local anesthesia with intravenous sedation is small but significant. The perioperative use of an upper body warming cover is protective.