Epidural analgesia-anaesthesia in obstetrics

Abstract

Epidural analgesia is the most effective and innocuous technique for obstetrics. Pain relief is its main indication but maternal diseases that might be decompensated by labour and delivery are also accepted indications. Low doses of long-acting local anaesthetics alone or in combination with low doses of fentanyl or sufentanil provide good quality analgesia and are safe for mother and fetus. Test doses in parturients lack sufficient specificity and sensitivity for detecting inadvertent intravascular injection, and subarachnoid migration of the catheter is possible at any time during the procedure. Therefore, every injection must be considered as a test dose and only fractionated injections must be made. Epidural block to T10 is needed for labour and to level T4 for Caesarean section. Maintenance of the block with a continuous infusion, or patient-controlled epidural analgesia with a background continuous infusion, provides more stable analgesia than by intermittent injection. Technical difficulties, dural tap, bloody tap, hypotension and insufficient block are most frequent complications of epidural block in obstetrics. Excessive motor block prolongs the second stage of labour and increases the frequency for instrumental delivery and is therefore considered a complication.