Patient-controlled sedation for ERCP: a randomized double-blind comparison of alfentanil and remifentanil

Background and study aims: Self-administration of a propofol and opioid mixture by patients (patient-controlled sedation, PCS) could offer a practical alternative for individual sedation during endoscopic retrograde cholangiopancreatography (ERCP). However, what would be the most suitable sedative mixture for PCS is unknown. The aim of this study was to compare remifentanil and alfentanil in the PCS during ERCP. Patients and methods: Eighty-one patients undergoing elective ERCP received PCS with propofol and opioid in three different regimens. The concentrations of opioids in the sedative mixture were 0.02 mg/mL in the remifentanil group (R) and 0.04 mg/mL and 0.08 mg/mL in the alfentanil 1 (A1) and alfentanil 2 (A2) groups, respectively. The infusion pump was adjusted to deliver a 1 mL single dose with zero lockout time. We considered PCS as successful if no procedure interruption due to sedation-related complications occurred or if additional propofol was not needed. The consumption of propofol was registered, and sedation levels and vital signs were monitored. Endoscopist and patient satisfaction with sedation were assessed using structured questionnaires. Results: The consumption (SD) of propofol was 177 (105) mg in group R, 197 (88) mg in group A1 and 162 (70) mg in group A2. PCS was successful in 74/81 (91%) of sedations, without differences between the groups in terms of propofol consumption, sedation success rate, sedation levels, vital signs, postprocedural pain, and endoscopist and patient satisfaction. Respiratory depression and nausea were observed more frequently with remifentanil than with alfentanil (P < 0.05). Conclusions: PCS is an acceptable method of sedation for ERCP. The combination of propofol and alfentanil should be recommended because a remifentanil-propofol mixture depresses spontaneous respiration more and produces nausea more frequently.