PHARMACOKINETICS AND EFFECTS OF IM ALFENTANIL AS PREMEDICATION FOR DAY-CASE OPHTHALMIC SURGERY IN ELDERLY PATIENTS

We have studied the pharmacokinetics and effects of im. alfentanil as premedication for peribulbar block in 90 patients undergoing elective day-case cataract surgery. We compared alfentanil 12.5 mug kg-1 inject ed into the deltoid (n = 30) or gluteal muscle (n = 30) 15 min before the peribulbar block, and placebo (n = 30). The alfentanil concentrati ons were significantly greater in the deltoid group during the study a nd the mean peak concentration occurred more rapidly in this group. On ly alfentanil injected into the deltoid muscle reduced pain (assessed with a visual analogue scale (VAS)) associated with the peribulbar blo ck. A mild sedative effect (VAS) was found in both alfentanil groups. We conclude that im. alfentanil appears to be a suitable premedicant f or short, painful procedures because it has a short duration of action and is not associated with any clinically significant side effects.