Lessening of pain on intravenous injection of Propofol-Lipuro by fentanyl and lignocaine pretreatment

Background Propofol-Lipuro 1% consists of long-chain triglycerides (LCT) and medium-chaintriglycerides that have been reported to cause less injection pain than traditional long-chain triglycerides. Objective This double-blinded prospective controlled study was designed to assess the effect of 100 mcg fentanyl pretreatment with venous occlusion on pain on injection of Propofol-Lipuro in comparison with lignocaine premixing, pretreatment, or placebo. Methods In a randomized double-blind controlled trial, 120 patients were assigned to receive one of the following four options: group 1: pretreatment with 2ml normal saline +18ml Propofol-Lipuro premixed with 2ml normal saline; group 2: pretreatment with 2ml normal saline + 18ml Propofol-Lipuro premixed with 2ml lignocaine 2%; group 3: pretreatment with 2ml lignocaine 2%+Propofol-Lipuro premixed with 2ml normal saline; and group 4: pretreatment with fentanyl 100 mcg/2 ml+ Propofol-Lipuro premixed with 2ml normal saline. Any associated pain or discomfort was categorized using a 4-point verbal rating scale.Results Twenty-one patients in group 1, 15 patients in group 2, 13 patients in group 3, and only seven patients reported pain in group 4 (Po0.001). Fourteen patients complained of moderate to severe pain in group 1 (six moderate and eight severe) and four patients complained of moderate to severe pain in group 2 (three moderate and one severe). Six patients complained of moderate to severe pain in group 3 (four moderate and two severe), compared with three patients who had severe pain in the fentanyl pretreatment group. No complications related to the study medications orpropofol were reported in any patient for the first 24-h perioperative time period. Conclusion Pretreatment with fentanyl incorporated into the anesthesia induction technique is a simple and effective way to alleviate pain during the injection of Propofol-Lipuro in addition to both premixing and pretreatment with lignocaine. All reduced the incidence and severity of pain on intravenous injection of Propofol-Lipuro with high statistical significance than placebo.