Neuraxial labor analgesia: Maintenance techniques

Since the advent of neuraxial analgesia for labor, approaches to maintaining intrapartum pain relief have seen significant advancement. Through pharmacologic innovations and improved drug delivery mechanisms, current neuraxial labor analgesia maintenance techniques have been shaped by efforts to maximize patient comfort during the birthing process, while minimizing undesirable side effects and promoting the unimpeded progress of labor. To these ends, a modern anesthesiologist may avail themselves of several techniques, including programmed intermittent epidural bolus (PIEB), patient controlled epidural analgesia (PCEA) and dilute concentration local anesthetic + opioid epidural solutions. We explore the historical development and the evidential underpinnings of these techniques, in addition to several contemporary neuraxial labor analgesia practices. We also summarize current understanding of the effects these interventions have on maternal/fetal health and the labor course, as well as several important aspects of analgesic safety and monitoring.