Effect of clonidine on heart rate variability during spinal anesthesia: randomized clinical trial [post]

2019 unpublished
Introduction:All anesthetic techniques act, in some way, in the Autonomic Nervous System. In spinal anesthesia this effect is well described. The administration of local anesthetics in the subarachnoid space produces sensitive and sympathetic motor block, however, with latencies and variable and independent block levels. Adjuvants administered in association with local anesthetics have the potential to prolong the duration of spinal anesthesia, increasing the incidence of side effects. The
more » ... e effects. The recovery of spinal anesthesia is based solely on the return of motor function and does not take into account the recovery of Autonomic Nervous System activity. Objective:To analyze the autonomic modulation of heart rate in patients undergoing surgical procedures under spinal anesthesia at the moment of recovery of motor function and to compare the autonomic function in patients who received bupivacaine in subarachnoid anesthesia with patients who recover bupivacaine associated with clonidine. Method:randomized, double-blind clinical trial. The sample consisted initially of 71 patients ASA I to III, submitted to surgery under spinal anesthesia. Patients were divided into 2 groups. Group B received only bupivacaine and group C received bupivacaine with clonidine. The Heart Rate Variability was evaluated during 10 min in three moments: (T1) rest, before the anesthesia; (T2) 20 min after the installation of the anesthetic block, and (T3) at the time of recovery of motor function. Linear methods, frequency domain and non-linear methods in the Chaos domain were used. Results:The approximate entropy in the clonidine group showed a elevation, which may suggest a protective effect on the cardiovascular system of the addition of clonidine in spinal anesthesia. Conclusion:The approximate entropy values at the moment of recovery of motor function in patients receiving spinal anesthesia with bupivacaine and clonidine present a reduction
doi:10.21203/rs.2.13790/v1 fatcat:6jtufgz6ijez5kityg6i6mjvai