Anesthesia and autonomic nervous system: is measurement of heart rate variability, blood pressure variability and baroreflex sensitivity useful in anesthesiology specialty?

The autonomic nervous system (ANS) contributes importantly to the short-term regulation of blood pressure and cardiovascular variability. Evidence from numerous studies indicates a strong association among compromised ANS, sudden cardiac death, blood pressure instability and adverse postoperative cardiac events. Heart rate variability (HRV), blood pressure variability (BPV) and baroreflex sensitivity (BRS) have been studied for years as tools for assessing ANS. In this review, physiological origin and measurement principle of cardiovascular fluctuations are described and changes in indices of HRV, BPV and BRS observed in various situations of anesthesia are discussed. Anesthesiologists need to consider estimation of ANS function to predict hypertension/hypotension after anesthesia induction and to improve short-term outcome and long-term cardiac morbidity and mortality. (