Background and Goal of Study: Local anesthetics cause sympathectomy and therefore hemodynamic disorders. The purpose of the study was investigation of the effect of local anesthetics on vegetative balance.
Materials and Methods: We have examined 37 males who had surgery on inguinal hernias under epidural anesthesia. 19 patients had epidural anesthesia with a 0.5% solution of bupivacaine, 18 patients - with a 0.75% solution of ropivakayine. In the perioperative period all patients underwent daily ECG monitoring by Holter with determination of heart rate variability (HRV). Normal values of HRV were determined on the basis of monitoring of healthy control individuals (12 males).
Results and Discussion: Compared with the control group in the examined patients in active period of monitoring LF/HF was significantly higher (1.83 and 4.48, respectively). In passive period LF/HF increased by 16.07%, p< 0.05 (to a value of 5.2). Compared with the control group in the examined patients pNN50% in active period of monitoring was lower (6.3 and 4.42, respectively). In passive period pNN50% nonsignificantly increased by 1.58% (to 4.49). In active period LF/HF was on 22.08% higher in group of ropivacaine as compare with bupivacaine. The values significantly increased in both groups in passive period (p< 0.05). However in group of ropivacaine LF/HF decreased only by 12.60%, in group of bupivacaine by 20.60%. The difference between groups decreased to 13.99%. In active period pNN50% was higher on 7.51% in group of ropivacaine. In passive period the values nonsignificantly increased in both groups. The difference between groups decreased to 6.73%.
Conclusion(s): Ropivacaine characterized by less pronounced inhibition of sympathetic activity. In our opinion due to this is less pronounced disorders of baroreflective regulation of the heart under the influence of ropivacaine and, thereafter, less pronounced clinical manifestations of sympathectomy (decreasing of blood pressure and bradycardia).
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