A comparison of granisetron and nitroglycerine for attenuating rocuronium pain: A double-blinded randomized, placebo controlled trial.

Background: The incidence of pain reported in literature after IV administration of rocuronium is 50-80%. The aim of our study was to determine whether pre-treatment with intravenous granisetron and nitroglycerine would reduce rocuronium-induced pain.
Methods: One hundred fifty patients of either sex, aged 18-65 years, American society of Anaesthesiologist grading (ASA) I-II, scheduled for various surgeries under general anesthesia were randomly assigned to one of the groups. Group G: received 2 granisetron (1mg/ml) diluted with 3 ml of 0.9% normal saline) while the Group C: received 5 ml of 0.9% normal saline. Group N: received 200΅g of nitroglycerine diluted to a total of 5 ml(with 0.9% normal saline). It was accompanied by manual venous occlusion for 20 seconds. Then 0.06mg/kg of rocuronium was injected through same cannula over 10-15 sec. Patients were asked by a blinded investigator to score the pain on injection of rocuronium using visual analogue scale (0-10) with 0-no pain,1-3 mild pain, 4-6 moderate and >=7 severe pain. At the same time discomfort in the form of patient's movement, such as no movement (grade 0), movement only wrist (grade 1), movement to the upper arm and shoulder of injected arm (grade 2) or generalized movements (grade3) was observed. Statistical analysis using independent t test, Mann-Whitney test and reverse ANOVA was done.
Results: 1. At 0 seconds, in group G number of patients who experienced withdrawl score of 0-1 were 92%,group N were 82% while only 26% of patients in group C had favourable withdrawl score.74% of patients in group C had score of 2-3 at same time. 2. At 0 sec, in group G number of patients who experienced VAS score of 0-3 were 96%, group N 72%. At same time Group C 48 % of patients had VAS score of 2-3.
Conclusion: We conclude that pre-treatment with granisetron or nitroglycerine both are highly effective in attenuation of rocuronium induced pain.