Comparison of the Analgesic Effectof Intramuscular Pethidine andIntramuscular Morphine on anOrthopedic Population in a CaribbeanTerritory

Introduction: Comparison of the analgesic effect of Intramuscular Pethidine and Intramuscular Morphine on an Orthopedic Population. Settings and Design: 1) Single Blinded Randomized Controlled study: Patients were divided into Morphine group or Pethidine group 2) Patient Satisfaction survey was administered to patients at the end of stay. Material and Methods: 1) Visual Analogue Scores (VAS) were taken at eight hourly intervals for three consecutive days or until the day of discharge. Incidence of opioid related complications was noted 2) A patient satisfaction survey was administered at the end of stay. Statistical Analysis: Average VAS during movement on day one during the 8am to 4pm period was calculated for both the morphine group and pethidine group. The percentage decrease in VAS was calculated for morphine vs. pethidine group on movement on Day 1. Pearson’s correlation was used to assess the relationship between opioid, side effects and overall patient satisfaction. T-test was used to evaluate the relationship between morphine, pethidine and twenty-four-hour pain relief.A one-way ANOVA test was used to evaluate the statistical significance between the morphine and the pethidine group and patient satisfaction. Results: The morphine group as compared with the pethidine group experienced an 18.5% decrease in Visual Analogue Score for pain on movement on day 1 (8 am-4 pm period). The morphine group was associated more drowsiness and prolonged time to first bowel action compared to the pethidine group. Only 1.4% (1) of patients experienced desaturation during the study which occurred in the morphine group. Overall, opioids were associated with minimal side effects and were generally safe to use. Patients who underwent regional anaesthesia used more morphine equivalents compared to those undergoing general anaesthesia. The morphine group was associated with overall increased patient satisfaction when compared to the Pethidine group. Conclusion: The study demonstrated a notable 18.5% decrease in VAS on movement with the morphine group as compared to pethidine group. Statistical significance was placed at 15%. Opioids were found to have a limited adverse side effect profile, with drowsiness and time to first bowel action being the most predominant. Only one patient representing 1.4% of the population had an episode of desaturation (Sp02 < 90%). Due to the minimal side effect profile opioids should be considered safe to use.