Respiratory Depression following Accidental Subarachnoid Pethidine

During the past two and a half years epidural pethidine has been used in this hospital to provide postoperative analgesia.The preparation (pethidine 50 mg in preservativefree saline, 10 ml) has been administered on patient demand by nursing staff for up to 48 hours after surgery.In this period more than ten thousand incremental doses of epidural pethidine have been given.CASE REPORT The patient, a 24-year-old gravida three, was booked for an elective repeat caesarean section and tuballigation.She had opted for a regional block and, accordingly, a combined epidural and subarachnoid block was planned.The rationale for this combined approach is to provide a dense and complete block of all nerve roots below T4, as described previously,l and also a route for postoperative epidural analgesia.The epidural space was located after some difficulty at the L3-4 interspace, and an 18 ga epidural catheter (Portex) was inserted.Although aspiration was not attempted there was no free flow of cerebrospinal fluid.