Simulated Bupivacaine Pharmacokinetics After Labor Epidural Analgesia Followed by Transversus Abdominis Plane Block With Liposomal Bupivacaine for Intrapartum Cesarean Delivery

( J Clin Anesth . 2024;99:111589. doi: 10.1016/j.jclinane.2024.111589) Cesarean delivery (CD) often results in severe acute pain, which has been associated with both persistent pain and postpartum depression; these associations have shown that the management of severe acute pain is imperative in the recovery process. Current recommendations from the Society for Obstetric Anesthesia and Perinatology (SOAP) include the use of intraoperative and postoperative opioid-sparing multimodal analgesia. Another established method of pain management for CD is transversus abdominis plane (TAP) blocks that use bupivacaine in either standard or long-acting formulations. Bupivacaine, however, has the potential for buildup in the body that can cause serious side effects. So far, there have not been any studies that assess the possibility of cumulative plasma concentrations of bupivacaine after epidural anesthetics followed by local anesthetics and a TAP block. This study was designed to simulate the pharmacokinetics of bupivacaine in several clinical scenarios surrounding labor analgesia and TAP blocks with or without bupivacaine, assessing the concentrations and determining if they remain below thresholds defined for toxicity.