Purpose: The purpose of this study was to investigate the dose-dependent effects of propofol on cognitive function and muscle power as well as vital functions.
Materials and methods: Twenty volunteers participated in this study. Each subject underwent 2 experiments in a randomized crossover manner (propofol group and control group). After control data were obtained, propofol at predicted effect site concentrations of 0.4, 0.8, 1.2, 1.6, and 2.0 μg/mL was infused in the propofol group using a target controlled infusion system. Heart rate, noninvasive blood pressure, arterial oxygen saturation, respiratory rate, and bispectral index value were monitored. Observer's assessment of alertness/sedation and the correct answer rate of the Stroop color word test were assessed. Muscle power, grip strength and bite force were measured.
Results: In the propofol group, the bispectral index value and observer's assessment of alertness/sedation scale dose-dependently reduced. At the predicted effect site propofol concentration of 2.0 μg/mL, 6 subjects became unconscious. The correct answer rate of Stroop color word test reduced at the predicted effect site propofol concentration of 1.6 and 2.0 μg/mL. Grip strength slightly increased at the predicted effect site propofol concentration of 1.2 μg/mL or less, and bite force dose-dependently increased. At the predicted effect site propofol concentration of 2.0 μg/mL, both muscle powers began to decrease. Bite force dose-dependently increased and reached the maximum at the predicted effect site propofol concentration of 1.6 μg/mL.
Conclusion: Although the detailed mechanisms are unknown, propofol dose-dependently increases bite force during minimal and moderate sedation.
Copyright © 2011 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.