Background
As the cranial nerve with the longest and widest distribution area of the body, the vagus nerve (N.Vagus) has both antinociceptive and neuromodulatory effects and plays a role in the regulation of the heart rate. The objective of this study is to investigate the impact of cold stimulation on vascular access discomfort and heart rate variability, specifically by separately stimulating the N. Vagus nerve on both the right and left sides of the neck thereby assessing any lateralization effect.
Methods
140 patients, ranging in age from 18 to 75, were randomly assigned to one of two groups: Group Left (Group L) or Group Right (Group R). Following cold application to the left lateral neck region of Group L and the right lateral neck region of Group R, venous cannulation was performed. Prior to, following, and subsequent to vascular access, the heart rate, noninvasive blood pressure, oxygen saturation, and numeric pain scale (NRS) values for venous cannulation pain of the patients were documented.
Results
Average heart rates and average heart rates after cannulation were considerably lower in both groups after vagal stimulation (p < 0.05). No significant difference was observed when comparing the average heart rate values for each time period in Group L and Group R, including the mean heart rate values before vagal stimulation, after vagal stimulation, and after vascular access (p > 0.05). The mean heart rate change percentages before and after vagal stimulation were 7 ± 5.8% and 7.1 ± 7.0% in group L and group R respectively, suggesting that heart rate variability was greater in Group R, although this difference was not statistically significant (p > 0.05). NRS values were found to be 2.64 ± 1.28 in Group L and 2.85 ± 1.62 in Group R, with no significant difference (p > 0.05).
Conclusion
While heart rate variability exhibited more prominence on the right side, the difference was not statistically significant. Analyzing the analgesic impact revealed no discernible difference between the analgesic effects of stimulation from the right and left sides.