Pain on injection of propofol with or without infusion of carrier fluid

Background: Propofol, a popular intravenous (iv) anaesthetic induction agen t for brief cases or day surgery, is associated with smooth induction, plea sant sleep, rapid recovery and little postoperative nausea. A major disadva ntage is pain at the site of injection. The aim of the present study was to examine the influence of simultaneous iv infusion of carrier fluid on prop ofol-induced local pain. Methods: Thirty patients, scheduled for car-nose-throat or plastic surgery under general anaesthesia, were randomly allocated into two groups. Each pa tient had two 2 ml iv bolus injections of propofol given at two minutes' in terval. In group I (n=15) the first bolus injection was given with no iv ca rrier fluid and the second one given with a 10 ml iv carrier fluid infused over 10 s. Correspondingly, the patients in group II (n=15) had their first injection with and their second one without the iv carrier fluid. Followin g each injection of propofol the patients were asked by a blinded investiga tor to score their pain on a 10-point visual analogue scale, and to report the appearance, maximum and disappearance of pain. After the second assessm ent of pain, general anaesthesia was induced with more propofol. Results: Pain intensity at the site of propofol injection was found not to be influenced by simultaneous iv infusion of carrier fluid. Conclusion: It seems, from the results obtained here, that simultaneous iv infusion of carrier fluid has no particular effect on local pain following iv administration of propofol.