Inhalation anesthesia with low flow of fresh gas
Background: The need to reduce pollution emissions in the operating room and to reduce treatment costs motivates more frequent use of general anaesthesia with a small or minimal fresh gas flow rate. Nevertheless, the reduction of the delivery of fresh gases should not influence the quality and safety of the anaesthesia.
Material and methods: A total of 100 patients were included in the study. The first group will consist of patients who are introduced into general anesthesia of high flow and the second group of patients in general low-flow anesthesia. For the purpose of the study, shorter operations will be selected for up to 2 hours. In all patients the bispectral index (BIS), heart rate, blood pressure, end-tidal carbon dioxide concentration and haemoglobin oxygen saturation were monitored.
Results: Heart rate (HR) and haemoglobin oxygen saturation (SaO2) were similar in both groups and the differences between them were statistically insignificant. There is a statistically significant difference in both systolic and diastolic pressure between the two groups. In the high-flow group, the systolic and diastolic pressure values were higher than in the low-flow group. The BIS values were similar in both groups and indicated that patients who underwent low-flow anaesthesia were not exposed to a higher risk of awakening during the procedure than the high-flow anaesthesia patients.
Conclusions: Use of both, low-flow and high-flow rate general anaesthesia provide patients adequate sleep depth and haemodynamic stability.