May be complicated by profound hypotension.
Match the description with the most appropriate type of obstetric anesthesia.
Parenteral narcotics are commonly used for labor pain. Meperidine is the most common opioid used for labor pain relief. It has a depressant effect on the fetus and can cause neonatal sedation. Pudendal block may provide adequate temporary pain relief for outlet operative vaginal deliveries in women not using regional analgesia. The success of a pudendal block depends on a clear understanding of the anatomy of the pudendal nerve and its surroundings. Complications (intravascular injection, hematoma, infection or abscess) are quite rare. Single-shot spinal analgesia provides prompt and adequate relief for procedures of limited duration such as cesarean delivery, rapidly progressing labor, or postpartum tubal ligation. The long-acting local anesthetic (with or without an opioid agonist) is injected at the level of the L4 to L5 interspace. Because of the inability to extend the duration of action, single-shot spinal analgesia is of limited use for management of labor. Epidural analgesia provides the most effective form of pain relief for the first and second stages of labor and for delivery. A catheter is placed in the epidural space, allowing for continuous infusion of local anesthetic agents or narcotics. The advantage of this method is that it can be titrated over time, and can be used for cesarean deliveries or postpartum tubal ligations. The most common side effect of regional analgesia is hypotension, which occurs in 25% to 67% of women undergoing spinal analgesia. Epidurals appear to lengthen the second stage of labor, and are associated with both an increased need for augmentation of labor with oxytocin and for instrument-assisted delivery.