The effectiveness of two different bolus doses of morphine for patient controlled analgesia in children

Abstract

PCA-IV is applied to children older than 5 years with two different doses of morphine and the results are evaluated. Twenty-eight patients ages ranging from 5 to 15 years undergoing major surgical procedures were included in this study. Following standard anaesthesia technique 0.1 mg/kg morphine was given intravenously. In group A (low dose group) patients weighing 0-20 kg. received bolus 0.5 mg, 20-30 kg patients received 1 mg and 30-40 kg patients received 1.5 kg and patients weighing more than 40 kg received 2 mg bolus dose of morphine in the PCA regimen. Group B (high dose) was administered 1 mg, 1.5 mg 2.0 mg and 2.5 mg bolus doses of morphine respectively. Four hour maximum limit doses was set to 400 mcg/kg. Patients were observed for 24 hours for the frequent complications (nausea, vomiting, itching, urinary retention, bowel motility), SpO2, respiratory rate, heart rate, systolic blood pressure, sedation and pain scores were recorded every hour. Faces Pain Scale average for 24 hours was 2.15±0.47 in group A and 1.67±0.5 in group B. The average sedation score was 0.79±0.23 and 0.87±0.3 in group A and B respectively. Group A delivered total of 19.5±12.2 mg (29 mcg/kg/hour) morphine and group B delivered total of 39.5±17.6 mg (50 mcg/kg/hour) morphine. High dose morphine bolus regimen achieved better analgesia and sufficient sedation. Morphine usage in high dose group (group B) was more frequent in the first 12 hours. Frequency of drug delivery and demand did not decrease in group A. The relation between demand and delivery let us to conclude that high dose bolus morphine is more suitable.