Comparison of the effects of lidocaine pre-administration and local warming of the intravenous access site on propofol injection pain: Randomized, double-blind controlled trial

Abstract

BackgroundLidocaine reduces pain that occurs upon the intravenous injection of propofol. But, there are few non-pharmacological nursing interventions to reduce propofol injection pain. ObjectiveTo compare the effects of lidocaine pre-administration and local warming of the intravenous access site on propofol injection pain. DesignProspective, double-blind, randomized controlled trial. SettingThe 555 bed, non-teaching National Cancer Center in Kyunggido, South Korea. ParticipantsA total of 96 patients who underwent thyroidectomy under total intravenous general anesthesia with propofol were randomly allocated to the control, lidocaine pre-administration (LA) or local warming (LW) group. MethodsAll three groups received 2% propofol with an effect-site target at 3μg/mL for induction dose. The control group received 2% propofol with no intervention. The lidocaine pre-administration group received 2% propofol 30s after 1% lidocaine 30mg. The local warming group received 2% propofol after warming of the intravenous access site for 1min using 43°C forced air. Propofol injection pain was assessed by four-point verbal categorial scoring (VCS), numerical rating scale (NRS) and surgical pleth index (SPI). ResultsPain VCS of the LA group (mean±SD, 1.11±0.45) was significantly reduced (U=−3.92, p<.001) compared to the control group (mean±SD, 1.71±0.74). Pain VCS of the LW group (mean±SD, 0.76±0.44) was significantly reduced (U=−5.17, p<.001) compared to the control group (mean±SD, 1.71±0.74). Pain VCS of the LW group was significantly reduced compared to the LA group (U=−3.33, p=.001]. Pain NRS of the LA group (mean±SD, 4.31±2.32) was significantly reduced (mean difference, 1.82; 95% CI, 0.63–3.00; p=.003) compared to the control group (mean±SD, 6.13±2.39). Pain NRS of the LW group (mean±SD, 3.06±2.37) was significantly reduced (mean difference, 3.07; 95% CI, 1.63–4.51; p<.009) compared to the control group. There were significant differences in pain NRS between the LA group and the LW group (mean difference, 1.25; 95% CI, 0.09–2.42; p=.035). SPI of the LA group (mean±SD, 64.1±16.3) was significantly reduced (mean difference control versus LA, 8.36; 95% CI, 1.64–15.1; p=.016) compared to the control group (mean±SD, 72.5±9.56). SPI of the LW group (mean±SD, 55.0±16.2) was significantly reduced (mean difference control versus LW, 17.4; 95% CI, 10.8–24.0; p<.001) compared to the control group. There was a significant difference in SPI between the LA group and LW group (mean difference, 9.06; 95% CI, 1.02–17.1; p=.028). ConclusionLocal warming of the intravenous access site by 43°C forced air for 1min is slightly more effective in reducing propofol injection pain compared to lidocaine pre-administration.