Pre-treatment with intravenous granisetron to alleviate pain on propofol injection: A double-blind, randomized, controlled trial

BACKGROUND: Propofol is one of the widely used intravenous (i.v.) anaesthetics, although pain on injection still remains a considerable concern for the anaesthesiologists. A number of techniques has been tried to minimize propofol-induced pain with variable results. Recently, a 5-HT(3) antagonist, ondansetron pre-treatment, has been shown to reduce propofol-induced pain. The aim of our randomized, placebo-controlled, double-blinded study was to determine whether pre-treatment with intravenous granisetron, which is routinely used in our practice for prophylaxis of post-operative nausea and vomiting, would reduce propofol-induced pain. METHODS: Eighty-two women, aged 18–50 years, American society of Anaesthesiologist grading (ASA) I–II, scheduled for various surgeries under general anaesthesia were randomly assigned to one of the two groups. One group received 2 mL 0.9% sodium chloride while the other group received 2 mL granisetron (1 mg/mL), and were accompanied by manual venous occlusion for 1 min. Then, 2 mL propofol was injected through the same cannula. Patients were asked by a blinded investigator to score the pain on injection of propofol with a four-point scale: 0=no pain, 1=mild pain, 2=moderate pain, 3=severe pain. RESULTS: Twenty-four patients (60%) complained of pain in the group pre-treated with normal saline as compared with six (15%) in the group pre-treated with granisetron. Pain was reduced significantly in the granisetron group (P<0.05). Severity of pain was also lesser in the granisetron group compared with the placebo group (2.5% vs. 37.5%). CONCLUSION: We conclude that pre-treatment with granisetron along with venous occlusion for 1 min for prevention of propofol-induced pain was highly successful.