Esmolol hypotension maintains tissue perfusion during myomectomy judged by Masimo monitoring of regional cerebral oxygen saturation and pleth variability index

Abstract

Objectives: To evaluate outcome of elective abdominal myomectomy under esmolol hypotensive anesthesia (HA) compared to normotensive anesthesia (NA). Methods: Patients were randomly divided into NA Group received NA and HA Group received esmolol (0.5 mg/kg) bolus then infusion (0.05–0.3 mg/kg/min) to maintain mean arterial pressure at 60–70 mmHg till completion of myomectomy. Masimo Radical 7 was used to monitor regional cerebral oxygenation (rSO2), total hemoglobin (Hb.) and pleth variability index (PVI). Fluid therapy (FT) included initial bolus of 5% human plasma protein followed by intraoperative (IO) Lactated Ringer's (LR) solution. Amount of IO blood loss, blood transfusion and urine output (UOP) were determined. Postoperative (PO) Hb. conc. was measured at laboratory (Lab). Results: IO blood pressure was significantly lower, while PVI was significantly higher with significantly lower ΔPVI with HA than NA. Operative time was significantly shorter with significantly less IO blood loss and blood transfusion with HA. Regional cerebral and peripheral tissue oxygen saturations showed non-significant difference between both groups. PO Masimo measured and Lab estimated Hb. was significantly higher with significantly lower ΔHb% in HA than NA group. Masimo measurement was significantly higher with significantly lower ΔHb% than lab estimation in both groups. Patients of NA group received significantly greater amount of LR, but UOP was non-significantly higher than in HA group. Conclusion: Esmolol HA allowed better control of IO bleeding, blood transfusion and FT. Masimo continuous monitoring of rSO2 assured preserved cerebral perfusion. Masimo measured PVI could non-invasively monitor tissue perfusion. Keywords: Elective myomectomy, Esmolol, Hypotensive anesthesia, Pleth variability index, Regional cerebral oxygenation