Effect of Intraoperative Propofol-Induced Sedation on the Neurotransmitter Levels (Pilot Study)

Abstract

The aim of the study was to determine the changes in the levels of various neurotransmitters depending on the depth of propofol-induced sedation.Material and methods. Twenty-four patients were included in a prospective, simple blinded study. All patients underwent elective orthopedic intervention with subarachnoid anesthesia and moderate (group 1, n=12) or deep (group 2, n=12) propofol-induced sedation. Peripheral blood sampling for measurement of neurotransmitter levels was performed before regional blockade (Stage 1), 35–40 min after the start of sedation (Stage 2), and 10–15 min after sedation was terminated and consciousness was recovered (Stage 3).Results. Deep propofol-induced sedation resulted in a decrease in norepinephrine level at stages 2 and 3. Under moderate sedation, its level decreased at Stage 2 and returned to baseline after restoration of consciousness. The initial concentration of norepinephrine (Stage 1) was higher in Group 2.Conclusion. Propofol-induced sedation resulted in reduced level of the main stress hormone, which suggests its stabilizing effect on autonomic nervous system.