Background: Intravenous opioid therapy is frequently used for postoperative pain management in children after orthopedic surgery but causes side effects such as respiratory depression, vomiting, sedation, and urinary retention. To investigate whether a continuous incisional fascia iliaca compartment (FIC) block provides more effective postoperative pain relief with fewer side effects than IV morphine, we performed a prospective, double-blind, randomized study to compare both techniques.
Methods: Thirty children (ASA physical status I-II) aged 3 mo to 6 yr undergoing a pelvic osteotomy were included in the study. The children were randomized for either morphine IV and placebo (saline) via a FIC catheter (Group M) or placebo (saline) IV and ropivacaine via a FIC catheter (Group R). All patients received general anesthesia using inhaled sevoflurane and IV fentanyl. Perioperatively, a FIC catheter was placed by the surgeon. All patients received either a bolus dose of morphine IV (Group M) or ropivacaine 0.75% via the FIC catheter (Group R) at the end of surgery. Postoperatively, Group M received morphine IV 20 microg x kg(-1) x h(-1) and Group R ropivacaine 0.2% 0.1 mL x kg(-1) x h(-1) via the FIC catheter. In both groups, saline was administered along the other route. All children were assessed for pain, sedation, time until first oral intake, and adverse effects for 48 h postoperatively. During this period, all children had a urinary catheter.
Results: The study was completed by 28 children. In the anesthetic recovery room, children in Group M had significantly higher pain scores. These children were also significantly more sedated during the study period. The incidence of vomiting did not differ between the groups; however, children in Group R had first oral intake significantly earlier than Group M. A local retrospective study revealed an incidence of urinary retention of 4.7% in the ropivacaine-treated patients and 39% in the morphine-treated patients.
Conclusions: Continuous incisional FIC block provides excellent postoperative pain relief, less sedation, and better return of appetite than morphine IV after pelvic osteotomy in children.