Epidural Bupivakainin Propofol, Alfentanil, Veküronyum Dozlarına ve Nöromusküler Blok Üzerine Etkisi: Randomize Prospektif, Tek Kör Klinik Çalışma

Abstract

Objective: This study was planned to ascertain the effects of epidural bupivacaine on the doses of propofol, alfentanil and vecuronium used for the maintenance for general anesthesia in patients receiving thoracic epidural anesthesia (TEA) combined with total intravenous anesthesia (TIVA) in thoracic surgery. In addition, the impacts of TEA on duration, intensity, reversal and the characteristics of residual block related to vecuronium-induced neuromuscular blockade was investigated. Material and Methods: Thirty patients scheduled for thoracic surgery were randomly assigned into two groups. Group 1 received TIVA combined with TEA, whereas Group 2 obtained TIVA solely. Epidural bupivacaine (0.375%) was given 6 mL/h following 1.5 mL/segment bupivacaine (0.5%) bolus in Group 1. General anesthesia was provided with propofol, alfentanil and vecuronium in both groups. Propofol dose was adjusted to maintain bispectral index (BIS) value between 45 and 60, whereas alfentanil dose was titrated according to the hemodynamic parameters. Following neuromuscular monitoring and stabilization of response to the neuromuscular stimulus, 0.1 mg/kg vecuronium was injected intravenously in 5 seconds. The responses to train of four (TOF) stimulation (TOF1 and TOF2), posttetanic count (PTC), and TOF rate (TOFR) values were recorded. The neuromuscular blockade was reversed after closure of surgical incision and the fourth response to TOF during recovery. The residual block was assessed in surgical intensive care unit for 30 minutes. Results: Alfentanil amount used in the maintenance was significantly less in Group 1 compared to Group 2 (p<0.05), whereas there was no difference between the groups for propofol and vecuronium doses (p>0.05). There was no statistically significant difference between the groups with respect to the onset time of vecuronium, TOF1 time following induction, and duration of the clinical effects of vecuronium used for induction and maintenance (p>0.05). Conclusion: It was demonstrated that epidural bupivacaine decreased the requirement of alfentanil without alterations in propofol and vecuronium doses in patients undergoing thoracic surgery in our study. We also suggest that in the present dose, epidural bupivacaine has no effect on duration, intensity, reversal or the characteristics of residual block related to vecuronium-induced neuromuscular blockade.