Effect of intraoperative magnesium intravenous infusion on the hemodynamic changes associated with right lobe living donor hepatotomy under transesophageal Doppler monitoring-randomized controlled trial

BACKGROUND: Liver donors are subjected to specific postresection hemodynamic changes. The aim was to monitor these changes and to evaluate the effect of magnesium sulfate infusion (MgSO(4)) on these changes together with total anesthetic agents consumption. PATIENTS AND METHODS: A total of 50 donors scheduled for right hepatotomy were divided into two equal groups. Controls (C) received saline and magnesium group (Mg) received MgSO(4) 10% (30 mg/kg over 20 min) administered immediately after induction of anesthesia, followed by infusion (10 mg/kg/h) till the end of surgery. Hemodynamics, transesophageal Doppler (TED) data and anesthetic depth guided by Entropy were recorded. RESULTS: Postresection both groups demonstrated an increase in heart rate (HR) and cardiac output (COP) in association with lowering of systemic vascular resistance (SVR). The increase in HR with Mg was lower when compared with C, P = 0.00. Increase in COP was lower with Mg compared to (C) (6.1 ± 1.3 vs. 7.5 ± 1.6 L/min, P = 0.00) and with less reduction in SVR compared to C (1145 ± 251 vs. 849.2 ± 215 dynes.s/cm(5), P < 0.01), respectively. Sevoflurane consumption was lower with Mg compared to C (157.1 ± 35.1 vs. 187.6 ± 25.6 ml, respectively, P = 0.001). Reduced fentanyl and rocuronium consumption in Mg group are compared to C (P = 0.00). Extubation time, postoperative patient-controlled fentanyl were lower in Mg than C (P = 0.001). CONCLUSION: TED was able to detect significant hemodynamic changes associated with major hepatotomy. Prophylactic magnesium helped to reduce these changes with lower anesthetic and analgesics consumption and an improvement in postoperative pain relief.