Propofol versus propofol-ketamine sedation for retrobulbar nerve block: Comparison of sedation quality, intraocular pressure changes, and recovery profiles

We compared sedation quality, intraocular pressure (IOP) changes, and recov ery profiles in patients who received propofol or propofol-ketamine sedatio n during placement of the retrobulbar nerve block (RBB). Seventy elderly pa tients undergoing cataract extraction according to a prospective, randomize d, double-blinded protocol were preoperatively evaluated with a Mini-Mental State examination and baseline IOP. A hypnotic dose was provided with eith er propofol (Group P) or a propofol-ketamine (Group PK) combination. The IO P measurement was repeated, and the surgeon initiated the RBB. Supplemental study drug was given if needed. The level of sedation was considered accep table if the patient exhibited minimal or no movement and grimacing with ne edle insertion. Patients were evaluated in terms of quality of sedation, ca rdiopulmonary stability, and recovery profile. Compared with patients in Gr oup P, patients in Group PK had a significantly faster onset of acceptable sedation (Group P 235 +/- 137 s versus Group PK 164 +/- 67 s) and required significantly less supplemental sedation (Group P1.1 +/- 1.9 mt versus Grou p PK 0.15 +/- 0.3 mt). Additionally, none of the Group PK patients required ventilatory assistance, but two patients in Group P required assisted mask ventilation. Ln conclusion, the addition of ketamine (13.2 +/- 3.3 mg) to propofol (44 +/- 11 mg) decreased the hypnotic requirement and improved the quality of sedation without prolonging recovery. Implications: Anesthesiol ogists frequently perform retrobulbar blocks while simultaneously providing sedation. Using ketamine to supplement propofol sedation provided a faster onset and improved the quality of sedation during the retrobulbar block pr ocedure.