Postoperative morphine consumption in children with sickle-cell disease

BACKGROUND: Effective pain control is a primary goal in the perioperative management of patients with sickle-cell disease. To understand analgesic requirements better, the authors compared postoperative morphine consumption and pain scores in sickle and non-sickle children who had undergone laparoscopic cholecystectomy. METHODS: We reviewed the medical records of all sickle and non-sickle children referred to the Acute Pain Service of a tertiary care teaching hospital for patient-controlled analgesia (PCA) following laparoscopic cholecystectomy from 1996 to 2003. Data collected included postoperative morphine consumption, visual analogue pain scores, and perioperative outcome. RESULTS: Total postoperative morphine consumption in sickle children (n = 12) (1.58 +/- 0.78 mg.kg(-1)) was more than double when compared with non-sickle children (n = 10) (0.65 +/- 0.32 mg.kg(-1)) (P < 0.005). Duration of PCA use among sickle children (51 +/- 25 h) was more than double when compared with non-sickle children (21 +/- 11 h) (P < 0.005). Sickle patients had greater pain scores in the initial 24 h after surgery (P < 0.05) and used more adjuvant analgesics (P < 0.05). Duration of postoperative hospital stay was 3.4 +/- 1.6 days and 1.5 +/- 0.5 days for sickle and non-sickle children, respectively (P < 0.005). CONCLUSIONS: Sickle children self-administered more than double the amount of morphine, reported more intense pain, and remained hospitalized for more than twice as long as nonsickle children undergoing the same surgical procedure. These findings probably have a multifactorial origin, and might be attributable in part to alterations in pain perception, opioid pharmacokinetics, opioid tolerance, and psychosocial variables.