Comparison of vasodilatory properties between isoflurane and sevoflurane using perfusion index: A randomized clinical trial

Abstract

Background: Sevoflurane and isoflurane are widely used volatile anesthetics with distinct vasodilatory profiles. Monitoring their effects on vascular tone is critical for optimizing anesthetic management and maintaining hemodynamic stability during surgery. Perfusion Index (PI), a non-invasive parameter obtained via pulse oximetry, serves as a reliable indicator of peripheral vasodilation. Objective: To compare the vasodilatory effect of sevoflurane and isoflurane using an evaluation of changes in PI, along with associated hemodynamic parameters such as mean arterial pressure (MAP) and heart rate (HR), in patients undergoing lumbar spine surgery under general anesthesia. Methods: From July 2022 to December 2022, a randomized controlled trial was conducted at Department of Anesthesiology, CMH Dhaka. Sixty patients of ASA grade I and II aged 25-50 years scheduled for decompression and stabilization surgery of prolapsed lumbar intervertebral disc (PLID) were randomly assigned to receive either isoflurane (Group A) or sevoflurane (Group B) at age-adjusted MAC-equivalent concentrations. Induction and maintenance was by standardized protocols. PI, MAP, HR, and blood pressure were recorded every three minutes for 35 minutes following induction. Data were compared between groups using the appropriate statistical tests. Results: Demographically and anthropometrically, the groups were comparable. Sevoflurane was associated with remarkably raised PI values, indicating greater peripheral vasodilation than isoflurane (p