COMPARISON OF METHOHEXITAL AND ALFENTANIL ON MOVEMENT DURING PLACEMENT OF RETROBULBAR NERVE BLOCK

We compared the use of methohexital (0.5 mg/kg) with alfentanil (20 mu g/kg) as a drug for limiting movement and pain during the placement o f a retrobulbar block (RBB). Thirty patients (ASA class I-III) were ra ndomly assigned to receive either methohexital or alfentanil (15 patie nts in each group). All but two patients (87%) treated with alfentanil were awake and responsive to command. All of the patients given metho hexital were unresponsive at the time of block placement. However, les s movement was observed when patients were treated with alfentanil com pared to methohexital (P < 0.0002). None of the patients treated with alfentanil complained of pain during placement of the RBB. No differen ce was detected in the incidence of respiratory depression. However, o ne patient who received alfentanil had a prolonged period of apnea (ap proximately 30 s) with a significant decrease in oxygen saturation. Th e incidence of nausea and vomiting and the time to discharge from the outpatient department were similar in the two groups. The results of t his study suggest that alfentanil may be used as a single drug to limi t movement during placement of retrobulbar block for ophthalmic surger y.