Comparison of two techniques (intermittent intravenous bolus morphine vs. morphine infusion) for analgesic titration in patients who had advanced cancer with severe pain: a prospective randomised study

Objective To compare the analgesic efficacy of two techniques of morphine titration (intermittent intravenous bolus vs infusion) by calculating rescue dosage in a day at 1 week after analgesic titration. Methods One hundred and forty cancer patients were randomised into two groups. In group 1, intravenous morphine 1.5 mg bolus given every 10 min until Numerical Rating Scale (NRS) pain score <4 is achieved. Total intravenous dose converted to oral dose (1:1) and administered every 4 hours. In group 2, intravenous bolus morphine 0.05 mg/kg body weight administered followed by 0.025 mg/kg/hour intravenous infusion. The NRS pain score was recorded every 10 min but infusion rate was titrated every 30 min if required. The infusion rate of morphine was doubled if the pain score was unchanged and increased to 50% when NRS was between 4 and baseline. If NRS<4, then infusion at same rate was continued. Once the NRS<4 for two consecutive hours, total intravenous dose for 24 hours was calculated and converted to oral morphine in a ratio of 1:3 and divided into six doses given over 24 hours. For rescue (pain score ≥4) analgesia, one-sixth of the total daily oral dose was prescribed. The primary outcome of this study was to note the number of rescue doses of oral morphine in a day at 1 week. Results The rescue dosage in a day at 1-week post discharge from the palliative care unit was significantly higher in group 1 as compared with group 2. Conclusion Intravenous infusion morphine may be a better analgesic titration technique for analgesia in patients with advanced cancer. Trial registration number CTRI/2018/04/013369.