Patient-controlled analgesia: epidural fentanyl and i.v. morphine compared after caesarean section

We have compared patient-controlled epidural fentanyl (PCEF) andpatient-controlled i.v. morphine (PCIM) after Caesarean section in 84patients, in a randomized, double-blind study. All patients had an epiduraland an i.v. patient-controlled analgesia (PCA) device, one of whichdelivered normal saline. Group PCEF received epidural fentanyl 20micrograms with a 10-min lockout. Group PCIM received i.v. morphine 1 mgwith a 5-min lockout. PCA use was lower for PCEF patients (P = 0.0007). Thehighest pain score recorded at rest for PCEF patients was median 20(interquartile range 10-33) mm compared with 32 (14-52) mm for PCIMpatients (P = 0.02). The highest pain score recorded on coughing was 31(21-41) mm with PCEF compared with 56 (30-71) mm for PCIM (P = 0.001).There was less nausea (P = 0.02) and drowsiness (P = 0.0003) with PCEF.There was no difference in the overall incidence and severity of pruritus(P = 0.77). However, pruritus started earlier with PCEF.