[Epidemiology of complications of obstetrical epidural analgesia]

Epidural analgesia (EA) is the best technique to obtain pain relief during labour. But the needle, the catheter and the local anaesthetics (LA) are 3 reasons to cause maternal complications. In France we do not know the exact number of EA performed every year and it is very difficult to appreciate the incidence of maternal complications. Therefore, it is necessary to know it and try to reduce the incidence of some of them. Maternal complications after EA are classically: 1. caused by catheter or needle: massive subarachnoid injection, toxic intravenous injection with convulsions and/or cardiac arrest; 2. secondary to infectious problems: meningitis or epidural abscess; 3. due to LA with the very rare anaphylactoid reactions; 4. due to prolonged neurologic complications with epidural and subdural haematomas, subarachnoid cysts or arachnoiditis. These complications are rare: 1/4,700 in the largest series of literature, involving more than 500,000 EA. In France, we tried to quantify maternal complications among nearly 300,000 EA performed over a period of 5 years. The overall incidence of serious complications was 1/4,005 EA. The most frequent are accidental dural puncture (1/156), massive subarachnoid injections (1/8,010) and convulsions (1/9,011). The incidence of these 3 complications must be reduced by better training, material or attention during bolus injection of LA.