Low-flow Sevoflurane Anesthesia in Laparoscopic Cholecystectomy

Abstract

There has been a revival of interest in low-flow anesthesia (LFA) techniques over the past decade or so, primarily driven by the introduction of newer anesthetic agents with low solubility and relatively higher costs. The advantages of LFA include a reduction in the consumption of anesthetic gases, reduced operating room and environmental pollution, and the conservation of heat and humidity within the respiratory tract of patients. Historically, most anesthesiologists have been trained to use high-flow anesthesia (HFA), and the anesthetic equipment and available anesthetic agents have not been suitable for LFA. HFA techniques, however, have the potential for inducing hypoxia and/or hypercapnia, administration of an overor underdosage of anesthetic gases, and the accumulation of potentially toxic degradation products. Laparoscopic cholecystectomy (LC) with intra-abdominal CO2 insufflation has a special anesthetic consideration in that it may induce hypercapnia, acidemia, and depressed hemodynamics. A number of studies have been published evaluating the use of LFA in a wide variety of surgical procedures, including gastrointestinal, gynechological and general surgery. Despite many advantages of the LFA as mentioned above, few studies have actually been done using LFA with sevoflurane in LC. One likely explanation is the potential for hypercapnia with LFA resulting from rebreathing exhaled CO2 coupled with an increase in arterial CO2 from the intraperitoneal CO2 insufflation. The purpose of this study was to investigate whether the LFA is safe and compatible with the LC involving abdominal CO2 insufflation.