Effect of dexmedetomidine on intraocular pressure in patients undergoing robot-assisted laparoscopic radical prostatectomy under total intravenous anesthesia: A randomized, double blinded placebo controlled clinical trial

Abstract

Study objectiveTo study the effects of intraoperative dexmedetomidine on the intraocular pressure (IOP) in patients undergoing robot-assisted laparoscopic radical prostatectomy (RALRP) under propofol–remifentanil anesthesia. DesignDouble-blind, randomized controlled trial. SettingOperating room. PatientsForty consenting male patients aged ≥20 to <80 years with American Society of Anesthesiologists physical status classes I and II. InterventionsThe patients were randomly assigned to either dexmedetomidine (DEX) (n = 20) or control (n = 20) group. Anesthesia was induced and maintained using propofol, remifentanil, and rocuronium. In the dexmedetomidine group, dexmedetomidine was administered at 0.4 μg/kg/h immediately after anesthesia induction until the end of the surgery, whereas normal saline was administered as placebo in the control group. MeasurementsIOP was measured using a rebound tonometer. Time points of measuring IOP were as follows: T1: before anesthesia induction, T2: 5 min after intubation, T3: 60 min after placing patient in the Trendelenburg position, T4: 120 min after placing patient in the Trendelenburg position, T5: 180 min after placing patient in the Trendelenburg position, T6: 5 min after placing patient in a horizontal position, T7: 5 min after extubation, and T8: 30 min after extubation. Main resultsA linear mixed model analysis demonstrated a significant intergroup difference in IOP over time and during pneumoperitoneum in the steep Trendelenburg position. IOP at T5 was significantly lower in the dexmedetomidine group than in the control group even after post-hoc analysis in the steep Trendelenburg position periods with Bonferroni correction. ConclusionsDexmedetomidine combined with propofol decreases IOP in the steep Trendelenburg position during RALRP.