Nicardipine Infusion for Hypotensive Anesthesia During Orthognathic Surgery Has Protective Effect on Renal Function

Abstract

PURPOSE: Hypotensive anesthesia may adversely affect renal function. The purpose of this study was to evaluate the renoprotective effect of nicardipine in patients undergoing orthognathic surgery under hypotensive anesthesia. MATERIALS AND METHODS: In this double-blinded randomized controlled study, healthy patients undergoing orthognathic surgery were enrolled to evaluate renal function during and after hypotensive anesthesia. The predictor variable was the agent, nicardipine vs remifentanil, used to maintain mean arterial pressure at 50 to 65 mm Hg. Primary outcome variables were renal function markers and secondary outcome variables were hemodynamic data, which were measured before hypotension, 2 hours after hypotension, 1 hour postoperatively (t3), and 24 hours postoperatively. Linear mixed model was used to analyze repeatedly measured data. RESULTS: Forty-six patients were randomly allocated to receive remifentanil (R group; n = 23) or nicardipine (N group; n = 23). The renal tubular function marker, urinary N-acetyl-1-β-D-glucosaminidase (NAG), was lower at t3 in the N group than in the R group (P = .014). In the N group, fractional excretion of sodium was significantly higher at t3 compared with baseline (P < .0001). The 2 groups did not show any differences in estimated creatinine clearance and serum cystatin C. CONCLUSION: Subclinical and reversible renal dysfunction appears during hypotensive anesthesia in patients undergoing orthognathic surgery. Continuous infusion of nicardipine attenuated the increase in NAG, which is a marker of renal tubular injury, during hypotensive anesthesia with desflurane and remifentanil.