[Reduction of pain on injection of propofol: a comparison of fentanyl with lidocaine].

We compared the effect of fentanyl and lidocaine on pain during injection of propofol. One hundred and sixty patients premedicated with midazolam were randomly allocated to one of four groups (n = 40, respectively); Group C, propofol 2 mg.kg-1; Group F, fentanyl 0.1 mg 3 min prior to propofol; Group L, lidocaine 40 mg added to 200 mg propofol; Group FL, fentanyl 0.1 mg 3 min prior to propofol mixed with lidocaine 40 mg. Propofol was injected via a vein on the dorsum of the hand in a half of the patients in each Group or the forearm vain in the other half. The incidence of pain was significantly less in both Group F (40%) and Group L (35%) compared with Group C (80%, P < 0.01). There was no significant difference in the incidence of pain between Group F and Group L. Group FL had the least incidence of pain (5%) of all Groups. Injection via the forearm vain tended to reduce the severity of pain compared with the vain on the dorsum of the hand. The time until loss of consciousness was significantly less in the groups receiving fentanyl than the groups without fentanyl (P < 0.01). In conclusion, prior administration of fentanyl is as effective as premixing of lidocaine in preventing the pain on injection of propofol, and the simultaneous application of them may abolish the pain.