Role of regional anesthesia in obstetric emergencies

Anesthesia in an obstetric emergency presents an additional risk to the mother, and may potentially have harmful effects on the fetus. Maternal risks can be significantly reduced by using regional anesthesia, whenever possible and general anesthesia be resorted to only when absolutely required. This is especially relevant in the developing countries where deaths under anesthesia may be significantly higher than in the 'west'. While CS done because of maternal hemorrhage or umbilical cord prolapse usually mandate general anesthesia, CS done because of a non-reassuring fetal status often permits the administration of a regional anesthesia. Close communication with the obstetrician helps determine whether the fetus, mother, or both are in immediate jeopardy requiring GA, or there is time to safely administer RA. There are situations where both neuraxial blocks and general anesthesia may both be contraindicated. In these situations, the use of regional anesthesia techniques such as transversus abdominis plane (TAP) block can be useful, providing not only anesthesia, but also postoperative pain relief. The loss of resistance technique for TAP blocks is a simple and reliable technique which can be done without the need for ultrasound guidance. An understanding of the 'cushion effect' significantly improves the success rate of this technique.