The relationship between core temperature and perioperative shivering during caesarean section under intrathecal anesthesia with bupivacaine and ropivacaine: a randomized controlled study

PURPOSE: To assess the incidence rate of perioperative shivering for cesarean section and explore the associations between the occurrence of shivering and hypothermia, core temperature change, local anesthetic. METHODS: This is a prospective, randomized, controlled, double-blinded study of 100 patients consenting for caesarean section under intrathecal anesthesia. Parturients with ASA I or II accepted elective caesarean section with combined spinal-epidural anesthesia (SA). 2–2.5 ml of 0.5% bupivacaine or 0.5% ropivacaine was intrathecally injected in group B and group R, respectively. RESULTS: The intraoperative shivering incidence in group B was significantly higher than that in group R (66.7 vs. 20.5%, Pvalue < 0.001), and shivering intensity in group B was significantly greater than group R (score: 1.4 vs. 0.3, Pvalue < 0.001). The core temperature in both groups gradually decreased with the time after SA. Hypothermia (core temperature < 36.0 ℃) 5–30 min after SA was not associated with shivering. However, changes of temperature at 25 and 30 min after SA, and bupivacaine were statistically associated with shivering, with the odds of 10.77 (95% CI: 1.36–85.21, P value = 0.02), 8.88 (95% CI: 1.29–60.97, P value = 0.03), and 7.78 (95% CI: 2.94–20.59, P value < 0.01), respectively. CONCLUSIONS: In our study, for cesarean section, the occurrence of shivering was associated with the local anesthetics and the change of core temperature after SA, while not the hypothermia.