A comparison of magnesium sulfate plus morphine with morphine alone for acute pain reduction in long-bone fractures; a double blind randomized clinical trial

Introduction: Acute pain is a common symptom in patients with bone fractures referring to the emergency department (ED). Objectives: The present study aimed at evaluating the efficacy of intravenous (IV) magnesium sulfate in controlling acute pain of long-bone fractures in EDs. Patients and Methods: The present double-blind, randomized clinical trial was conducted on patients with isolated limb fractures referred to Golestan hospital of Ahvaz from 2019 to 2020. Patients in the intervention group were injected with 0.1 mg/kg morphine plus 30 mg/kg magnesium sulfate and 0.1 mg/kg morphine alone in the morphine group. The patient’s pain scores were measured at 0, 15, 30, 45 and 60 minutes after injection. The patients’ condition was monitored every 10 minutes, including respiratory and pulse rate, blood pressure, and knee reflex. Results: The present study was conducted on 64 patients with long-bone fractures allocated to two groups of IV morphine plus magnesium sulfate and IV morphine alone (each of 32). The hemodynamic factors and mean body temperature did not significantly change after intervention and had a similar level in both groups. Before the intervention, the mean score of pain was measured in the morphine and magnesium sulfate plus morphine groups using a visual analogue scale. Results which were 8.87±0.83 and 8.93±0.94, respectively, showing no significant differences (P=0.69). After 60 minutes, the pain score reduced considerably in both groups. Conclusion: In the study, magnesium sulfate plus morphine could better reduce pain than morphine alone without influencing the respiratory rate. Trial Registration: The trial protocol was approved by the Iranian Registry of Clinical Trials (IRCT20190617043913N1; https://en.irct.ir/trial/40370, ethical code# IR.AJUMS.REC.1398.143).