The Effect of General and Epidural Anesthesia in Women undergoing Cesarean Section on Power Spectral Components of Heart Rate Variability: Clinical Study

Park, Chong Doo; Ko, Hong; Kwak, Il Yong

Abstract

BACKGROUND: The analysis of beat-to-beat heart rate variability has become a method of assessing the state and health of the autonomic nervous system. Power spectral analysis(PSA) has become one of the most widely used techniques to describe heart rate variability.
METHODS
We analyzed the heart rate variability using PSA before and during general and epidural anesthesia in cesarean section. We anesthetized 12 patients by enflurane, and 15 patients by 2% lidocaine via epidural catheter. Automatic computer analysis provided PSA. The PSA contained two major components, a low frequency(LF) at 0.04~0.15 Hz, and a high frequency(HF) at 0.15-0.50 Hz.
RESULTS
Before anesthesia, P(LF)(spectral power of LF-unit; sec2/Hz) is 0.06(0.03, 0.34) {median(5 percentile, 95 percentile)}, P(HF), 0.83(0.22, 1.68), total spectral power(Ps), 1.98(O.86, 3.88), and P(LF)/P(HF), 0.67(0.17,1.67) in general anesthesia group. During anesthesia, P(LF) is 0.06(0.03, 0.34), P(HF), 0.12(0.04, 0.76), Ps, 0.43(0.24, 1.71), P(LF)/P(HF), 0.70(0.24, 2.59). In epidural group, before anesthesia, P(LF) is 0.30(0.11, 1.94), P(HF), 0.78(0.14, 1.94), Ps, 1.81(0.58, 5.23), P(LF)/P(HF) 0.47(0.25, 1.34). During anesthesia, P(LF). is 0.14(0.05, 0.41), P(HF), 0.33(0.07, 0.80), Ps, 0.81(0.34, 1.58), P(LF)/P(HF), 0.58(0.22, 1.08).
CONCLUSIONS
In general anesthesia, P(LF) P(HF) and Ps during anesthesia showed significant decrease than pre-anesthetic period, but P(LF)/P(HF) did not change. In epidural anesthesia, P(LF)/P(HF) and Ps during anesthesia also decreased, but P(LF)/P(HF) did not change. There were significant differences in degree of decrease in Ps and P(HF) between general and epidural anesthesia, but no differences in and P(LF)/P(HF).