Comparison of Effects of Isoflurane and Propofol on Body Temperature Changes during Knee Arthroscopy Surgery

Anesthesiologists are often facing patients who suffer from hypothermia during anesthesia and shivering after surgery. This study compared the effects of anesthesia with isoflurane and propofol on the intensity of body temperature reduction during anesthesia in knee arthroscopy surgery.
Material & The study was done as a double blinded randomized clinical trial. From 40 patients who underwent knee arthroscopy surgery, 20 subjects were placed in isoflurane group and 20 in the propofol group. Changes in surface and core body temperature, hemodynamic, and shivering after anesthesia in different times were evaluated. The central body temperature for each patient was measured through the tympanic membrane, and the surface temperature of the body was measured through the axillary. SPSS was used for statistical analysis. Data were compared via Student’s t-test analysis. Changes between time points were examined using repeated measurement ANOVA. Comparison of qualitative variables was done by Chi-square test between groups.
Core body temperature in propofol group significantly increased compared with the isoflurane group during anesthesia and after anesthesia (P0.05), and surface body temperature in propofol group significantly increased in the isoflurane group during and after the anesthesia (P0.05); in the propofol group, the chill rate increased more significantly than the isoflurane group. Furthermore, changes in systolic blood pressure and diastolic blood pressure showed no significant difference between the two groups at different times during and after the anesthesia (P>0.05).
It seems that propofol is better than isoflurane in controlling body temperature during and after anesthesia and shivering post-surgery.