A Comparison Of Metoclopramide And Lidocaine For Preventing Pain On Injection Of Propofol

One of the disturbing complications of propofol is pain on injection and the incidence ranges from 28% to 90%. Metoclopromide is commonly used as an anti emetic drug. Some investigators reported that this drug could reduce the pain on injection of propofol. The aim of this study was to assess and comparison of the efficacy of propofol pretreatment with metoclopromide in incidence and severity of its pain on injection. In a randomized, prospective, double-blinded, placebo-controlled trail, 150 patients 18 to 40 yr old were randomly allocated in one three groups. C group (2ml of normal saline), L group (40mg lidocaine in 2ml), M group (l0mg metoclopromide in 2ml). Immediately after injection of study or placebo drugs, 10 mg of propofol with injection rate of 0.5 ml/s (In 4 Seconds) were injected in to the same vein that was inserted to the most prominent dorsal hand vein. Pain severity was measured using Visual Analogue Pain Scale that were educated to the patients before the trail (0 for no pain and 100 for the most aggressive pain in life) and values other than zero was encountered pain appearance. Patients with signs of sedation were excluded. There was no statistically significant difference between patients in three groups in number of men and women (P = 0.66), age (P = 0.29) and weight (P = 0.49). Furthermore severity (P = differences (C = 41.18, L - 25.4 and M = 13.1, P < 0.001) and patients in metoclopromide group experiences lower pain than other two groups (P < 0.001). Pain incidence in Control group was 77.1% and it was significantly reduced in lidocaine and metoclopromide group (P = 0.002), but there were no significant difference between them (P = 0.051). The 0.69) and incidence (P ~ 0.29) of pain has no significant difference between men and women. Pain severity between three groups has significant results showed that metoclopromide could significantly reduce the seventy of pain on injection of propofol more than lidocaine (opposite to diazepam), but they had no difference in pain incidence. It might lie on the different mechanisms that they produce pain. Pain on injection of diazepam is primarily attributed to propylene glycol, as a vehicle, but the pain mechanism in propofol is remaining unknown. Finally as regards to other useful effects of metoclopromide including postoperative nausea and vomiting and propofol induction dose reduction, especially when there is a medical condition where lidocaine is contraindicated, it may be a reasonable alternative before injection of propofol.