Serious complications associated with epidural/spinal blockade in obstetrics: a two-year prospective study.

A prospective study of complications associated with epidural and spinal blockade in obstetrics was carried out during the years 1990 and 1991. 79 obstetric units in the United Kingdom took part. These units had a total of 467 491 deliveries during the two years. 108 133 mothers received epidural blockade and 14856 received spinal blockade. 22% of all mothers received epidural analgesia in labour, and 50% of caesarean sections were performed under either epidural or spinal anaesthesia. 128 complications (not including post dural puncture headache) were reported. Of these, 46 were neuropathies involving a single spinal or peripheral nerve. 26 unexpectedly high blockades were encountered. Backache was reported in 21 mothers and urinary retention in 8. Cardiac arrest occurred twice. Although resuscitation restored normal cardiac function in both cases, one patient was decerebrate and died some days later. Postmortem examination revealed evidence of amniotic fluid embolus. 20 reports were classified as 'miscellaneous' and presented individual clinical diagnoses. The overall complication rate (excluding post dural puncture headache) was approximately 1 per thousand.