Comparison of arterial lactate levels during sevoflurane versus spinal anesthesia in elderly females undergoing total knee arthroplasty

Abstract

Prolonged tourniquet inflation during total knee arthroplasty (TKR) could lead to ischemic muscle injury. The aim of this study was to investigate the effects of spinal and sevoflurane anesthesia on arterial lactate levels, acid-base status, and on hemodynamic variables in elderly women undergoing TKR. Forty women more than 65 years of age scheduled for elective TKR were enrolled in this study. Patients were allocated to receiving either sevoflurane anesthesia (sevoflurane group, n = 20) or spinal anesthesia (spinal group, n = 20) according to the patient's decision. Arterial lactate levels were significantly higher in the sevoflurane group than in the spinal group at 5 and 65 min after tourniquet deflation (P < 0.001 and P = 0.033, respectively), but there were no intergroup differences in the increment of arterial glucose levels at any time point. Mean arterial pressure and heart rate were significantly higher at 5 min before tourniquet inflation (P < 0.001, P = 0.029, respectively) and lower at 65 min after tourniquet deflation (P = 0.009, P = 0.033, respectively) in the spinal group than in the sevoflurane group. Our results suggest that spinal anesthesia is associated with lower production of ischemic metabolites than sevoflurane anesthesia after pneumatic tourniquet deflation in elderly women undergoing TKR.