Transdermal fentanyl administration in children and adolescents with sickle cell pain crisis

Purpose: The purpose of this study was to determine the dose-concentration relationship and clinical effect of transdermal fentanyl (TF) in patients with sickle cell pain crisis (SCPC). Patients and Methods: Ten patients aged 9-16 years were studied. Patients initially received a TF dose of 25 (n = 7) or 50 (n = 3) mu g/h if morphine use was >2.5 mg/h. Supplemental morphine usage via patient-controlled analgesia (PCA), sedation status, pain status, respiratory rate, pulse rate, oxygen saturation, and blood pressure were monitored. Results: The average TF dose was 0.77 +/- 0.37 mu g/kg/h on day 1 and 1.17 +/- 0.46 mu g/kg/h on day 2. Fentanyl concentrations measured at 24 and 48 h were 0.60 +/- 0.31 and 1.18 +/- 0.44 ng/ml, respectively. A significant relationship existed between TF dose and fentanyl concentration (r(2) = 0.56, p < 0.01). There was no difference in any of the clinical monitoring parameters between day 1 and day 2. However, 7 of 10 patients reported subjective improvement in pain control over that achieved with PCA alone. No adverse effects were noted. Conclusions: Improved understanding of the dose-effect relationship for TF in children and adolescents is necessary before adequate pain control can be achieved with this delivery system.