Effects of Remifentanil on Cardiovascular Stimulation Caused by Local Anesthetic With Epinephrine: A Power Spectral Analysis
The objectives of this research were to investigate (a) what was the most effective infusion rate of remifentanil and (b) the degree to which sympathomimetic effects were involved with cardiovascular stimulation by using a power spectral analysis of heart rate variability (HRV). A total of 63 healthy individuals scheduled for sagittal split ramus osteotomy were enrolled and randomly allocated to 1 of 3 groups: remifentanil infusion rate of 0.1, 0.2, or 0.4 μg/kg/min. Anesthesia was maintained with remifentanil and propofol. Before the surgical procedure, 2% lidocaine containing 12.5 μg/mL epinephrine was administered in the surgical field for local anesthesia. Systolic blood pressure (SBP), heart rate (HR), low-frequency (LF) and high-frequency (HF) components in HRV power spectral analysis, and the LF/HF ratio were analyzed. Increases in SBP and HR were observed after local anesthesia in all 3 groups, but no significant differences were observed between the groups. Remifentanil infusion at 0.1 μg/kg/min may be appropriate to minimize cardiovascular stimulation caused by exogenous epinephrine from local anesthesia. Although a rise in the LF/HF ratio was observed after local anesthesia in all groups, no relationship was observed between the cardiovascular changes and the increase in LF/HF ratio. This suggests that sympathomimetic effects are involved to a lesser extent with the cardiovascular stimulation caused by exogenous epinephrine.
Schema of experimental protocol.
Relationship between percentage changes in low-frequency/high-frequency (LF/HF) ratio and percentage changes in systolic blood pressure (SBP). The LF/HF ratio rose after local anesthetic administration in all 3 groups, but no relationship between these values and percentage changes in SBP was observed. X axis: percentage changes in highest LF/HF ratio compared to baseline value. Y axis: percentage changes in highest SBP compared to baseline value.
Relationship between percentage changes in low-frequency/high-frequency (LF/HF) ratio and percentage changes in heart rate (HR). The LF/HF ratio rose after local anesthetic administration in all 3 groups, but no relationship between these values and percentage changes in HR was observed. X axis: percentage changes in highest LF/HF ratio compared to baseline value. Y axis: percentage changes in highest HR compared to baseline value.
Relationship between percentage changes in high-frequency (HF) values and percentage changes in systolic blood pressure (SBP). HF rose after local anesthetic administration in all 3 groups. No correlation was observed between these values and percentage changes in SBP. X axis: percentage changes in highest HF compared to baseline value. Y axis: percentage changes in highest SBP compared to baseline value.
Relationship between percentage changes in high-frequency (HF) values and percentage changes in heart rate (HR). HF rose after local anesthetic administration in all 3 groups. No correlation was observed between these values and percentage changes in HR. X axis: percentage changes in highest HF compared to baseline value. Y axis: percentage changes in highest HR compared to baseline value.
Relationship between percentage changes in low-frequency (LF) values and percentage changes in systolic blood pressure (SBP). LF rose after local anesthetic administration in all 3 groups, but no correlation was observed between these values and percentage changes in SBP. X axis: percentage changes in highest LF compared to baseline value. Y axis: percentage changes in highest SBP compared to baseline value.
Relationship between percentage changes in low-frequency (LF) values and percentage changes in heart rate (HR). LF rose after local anesthetic administration in all 3 groups, but no correlation was observed between these values and percentage changes in HR. X axis: percentage changes in highest LF compared to baseline value. Y axis: percentage changes in highest HR compared to baseline value.
Contributor Notes