Comparison of minimal flow anesthesia and inhalation agent costs in bariatric surgery

INTRODUCTION AND AIM: Low and minimal flow anesthesia applications have regained popularity due to their impact on anesthesia costs, environmental pollution, and ecological damage. However, there are concerns regarding the use of low-flow anesthesia in obese patients. In this study, we applied low-flow anesthesia for wash-in and minimal-flow anesthesia for maintenance in patients undergoing bariatric surgery using sevoflurane and desflurane. We compared the consumption amounts and costs of inhalation agents as well as the time required to reach 1 MAC between the two groups. MATERIAL AND METHODS: Ethical approval for the study was obtained from the local ethics committee, and informed consent was provided both verbally and in writing by all patients prior to the study. Sixty patients undergoing bariatric surgery were divided into two groups based on the type of inhalation agent used for anesthesia maintenance: the sevoflurane group (Group S, n = 30) and the desflurane group (Group D, n = 30). In both groups, adequate anesthetic saturation (wash-in) was achieved using low-flow anesthesia (60% O2 with air, total gas flow [TGF] of 1 L/min). Vaporizers were set to 6% for sevoflurane and 18% for desflurane. After reaching 1 MAC, the TGF was adjusted to 0.5 L/min with 70% O2 in air. The time to reach 1 MAC, inhalation agent consumption, anesthetic depth, anesthesia and surgery durations were analyzed, and the cost of inhalation agents was calculated. RESULTS: The anesthesia duration, surgical duration, and anesthetic depth were similar between the two groups. The total amount of inhalation agent consumed during the operation was significantly higher in the desflurane group compared to the sevoflurane group. However, when comparing the total inhalation agent costs, the cost in the desflurane group was significantly lower than in the sevoflurane group. Additionally, the hourly cost in the desflurane group was significantly lower than in the sevoflurane group. The time to reach 1 MAC was significantly shorter in the desflurane group compared to the sevoflurane group. CONCLUSIONS: According to the results of our study, low-flow anesthesia with desflurane was observed to be more cost-effective compared to the sevoflurane group. Additionally, the time to reach 1 MAC was shorter in the desflurane group.