Premedication with oral paracetamol for reduction of propofol injection pain: a randomized placebo-controlled trial

Sasikaan Nimmaanrat,Sumidtra Prathep,Maliwan Oofuvong,Manasanun Jongjidpranitarn

doi:10.1186/s12871-019-0758-y

Sasikaan Nimmaanrat, Sumidtra Prathep + Show 2 more

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https://doi.org/10.1186/s12871-019-0758-y

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Journal: BMC anesthesiology	Publication Date: Jun 11, 2019
Citations: 3	License type: open-access

Affiliation: Prince of Songkla University

Abstract

BackgroundTo compare the effect of premedication with 2 different doses of oral paracetamol to prevent pain at propofol intravenous injection.MethodsWe conducted a double-blind randomized controlled trial in which patients scheduled for induction of general anesthesia with intravenous propofol received either a placebo, 500 mg or 1000 mg of oral paracetamol (P500 and P1000, respectively) 1 h prior to induction. Two mg/kg of propofol was injected at a rate of 600 ml/hr. After 1/4 of the full dose had been injected, the syringe pump was paused, and patients were asked to rate pain at the injection site using a verbal numerical rating score (VNRS) from 0 to 10.ResultsThree hundred and twenty-four patients were included. Pain intensity was lower in both P500 and P1000 groups (median VNRS [interquartile range] = 2 [0–3] and 4 [2–5], respectively) than in the placebo group (8 [7–10]; P < 0.001)*. The rate of pain was lower in the P1000 group (70.4%) than in both the P500 and the placebo group (86.1 and 99.1%, respectively; P < 0.001)*. The respective rates of mild (VNRS 1–3), moderate (VNRS 4–6) and severe pain (VNRS 7–10) were 47.2, 23.2 and 0% in the P1000 group, 28.7, 50 and 7.4% in the P500 group, and 0, 22.2 and 76.9% in the placebo group (P < 0.001* for between group comparisons). Tolerance was similar in the 3 groups.ConclusionsA premedication with oral paracetamol can dose-dependently reduce pain at propofol intravenous injection. To avoid this common uncomfortable concern for the patients, this well-tolerated, available and cheap treatment appears as an option to be implemented in the current practice.Trial registrationTCTR20150224002. Prospectively registered on 24 February 2015.

Highlights

To compare the effect of premedication with 2 different doses of oral paracetamol to prevent pain at propofol intravenous injection
All participants were completely analyzed. (Fig. 1) There were no differences between the groups regarding gender, age, weight, height, body mass index (BMI), American Society Anesthesiologists (ASA) physical classification and interval between ingestion of paracetamol and injection of propofol. (Table 1)
The incidence of pain was less in the P1000 group (70.4%) compared with the paracetamol 500 mg (P500) (86.1%) and the Pb groups (99.1%) (P < 0.001)

Summary

Introduction

To compare the effect of premedication with 2 different doses of oral paracetamol to prevent pain at propofol intravenous injection. Pain upon injection of some anesthetic agents are thought to be a direct irritant effect by the non-physiological osmolality or pH of their preparations [4]. Propofol is nearly isotonic, nonhyperosmolar and has a pH from 6 to 8.5. This concept cannot explain for the pain produced by the injection of propofol [1]. Propofol injection pain may be caused by an effect via the kinin cascade [5]. Many factors seem to contribute to the incidence of injection pain including site [6] and speed of injection [7], size of vein [7, 8], rate of intravenous fluid infusion [9], concentration of propofol in the aqueous phase [4] as well as blood buffering effects [10]

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