Assessment of Autonomic Response before and after Total Spinal Anesthesia in Rats: Power Spectral Analysis.
10.4097/kjae.2005.48.2.182
- Author:
Gyu Sam HWANG
1
;
In Young HUH
;
Su Jin KANG
;
Mi Ok YOUN
;
Won Jung SHIN
;
Byung Moon CHOI
;
Su Keoung LEE
;
Seong Sik KANG
;
Jeong Lak LEE
;
Sung Kang CHO
Author Information
1. Department of Anesthesiology and Pain Medicine, College of Medicine, University of Ulsan, Asan Medical Center, Seoul, Korea. kshwang@amc.seoul.kr
- Publication Type:Original Article
- Keywords:
baroreflex sensitivity;
cross-spectral analysis;
total spinal anesthesia
- MeSH:
Anesthesia, Epidural;
Anesthesia, Spinal*;
Anesthetics, Local;
Animals;
Autonomic Nervous System;
Baroreflex;
Blood Pressure;
Cranial Nerves;
Fourier Analysis;
Heart Rate;
Peripheral Nerves;
Rats*
- From:Korean Journal of Anesthesiology
2005;48(2):182-189
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: Total spinal anesthesia (TSA) after injections of local anesthetics into the intrathecal space during epidural anesthesia is not rare. TSA anesthetizes cranial nerves and peripheral nerves, causes specific circulatory disturbances related to autonomic imbalance. Spectral analysis of heart rate variability (HRV) and blood pressure variability (BPV) provide a dynamic assessment of sympathetic and parasympathetic tone. Cross-spectral analysis has been used to emphasize this dynamic baroreflex control of HR as a frequency-dependent phenomenon and allows an assessment of baroreflex function. To examine the effects of TSA on the autonomic nervous system, we used spectral and cross-spectral analytic METHODS. METHODS: We investigated 14 rats before and after TSA. Power spectral densities of blood pressure (BP) and heart rate (HR) were estimated by fast Fourier transform. To evaluate the effect of TSA on baroreflex function, the cross spectral gain, phase, and coherence between beat-to-beat BP and HR signals were calculated by using transfer function analysis. RESULTS: With the onset of TSA, BP and HR significantly decreased. TSA significantly decreased the low frequency (LF) and high frequency (HF) components of HRV and BPV. Baroreflex sensitivity (BRS) obtained from transfer function gain between these variables was significantly decreased. CONCLUSIONS: TSA reduces the LF and HF components of HRV and BPV. These suggest that TSA in rats decreases both parasympathetic and sympathetic drive. Moreover, the decrease in BRS suggests impairment of cardiac baroreflex buffering function during TSA.
