The effects of anesthesia techniques and ambient temperature on patient thermoregulation and recovery in lower extremity surgery

ABSTRACTThe Effects of Anesthesia Techniques and Ambient Temperature on Patient Thermoregulation and Recovery in Lower Extremity SurgeryHypothermia is the most common thermoregulatory defect which brings many other problems. The main purpose of our study is to determine the effects of anesthesia technique, which was applied to extremity surgery patients, and ambient temperature on thermoregulation.After the approval of Ethic Council of Medical Faculty of Fırat University, lower extremity surgery planned ASA I-II group 90 male patients were integrated into the study and their ages were between 18 and 60. These patients were classified into 3 classes indiscriminately as general anesthesia (GA), epidural anesthesia (EA) and femoral-sciatic block (FS). The groups were then divided into subgroups in terms of ambient temperature (20-22 °C (I) and 23-25 °C (II)), (Group GA I, GA II, EA I, EA II, FS I and FS II). No premedication was implemented patients were standard monitored. Temperature probes were placed in tympanic membrane, axilla, chest, arm, inner half or fore arm and the pulp of middle finger in the hand and mean skin temperature (MST) and mean Body Temperature (MBT) were calculated at right before the anesthesia induction (basal) and at 5th,10th, 15th, 20th, 30th, 45th, 60th, 90th and 120th minutes after the induction. A postoperative 15th, 30th, 45th and 60th minutes, tympanic membrane, recovery room temperature, pain evaluation by VAS, axilla temperature and shivering and nausea-vomiting scores were recorded.No significant difference between the demographic data of patients was detected. After anesthesia implementation, decrease of tympanic and MBT and increase of MST were monitored at all of the patients. The significant difference between different ambient temperature and anesthesia techniques implemented patients was not determined for tympanic temperature (p>0.05). The significant decrease of MST in group GA I in comparison with group GA II was monitored at 5th , 10th , 15th , 20th , 60th and 90th minutes (p<0.05). A significant basal period decrease of MBT in group GA I in comparison with group GA II was monitored (p<0.05). It was also monitored that the MST value of group GA I at 5th minute was significantly lower than that of group FS I (p< 0.05). During the post-operative period comparisons between the groups, no significant difference could be determined in terms of tympanic temperature, axilla temperature and nausea-vomiting scores. The Shivering Score of group GA I, and the VAS Score of group GA I and GA II was determined significantly higher than other groups (p<0.05).As the result of our study; though there was no significant difference between implemented anesthesia techniques, it was seen that only the general anesthesia implemented patients were affected by ambient temperature.Keywords: Thermoregulation, General anesthesia, Epidural anesthesia, Femoral-sciatic block, Ambient temperature