Changes in Sensory Block Level During a Programmed Intermittent Epidural Bolus Regimen for Labor Analgesia: A Prospective Observational Cohort Study

(Can J Anesth/J Can Anesth. 2022;69:1471–1476) Currently, one of the most widely used methods of pain management is epidural analgesia, with drug delivery in a programmed intermittent epidural bolus (PIEB) in conjunction with patient-controlled epidural analgesia. Previously the investigators reported 2 sensory block levels associated with epidural analgesia: (1) upper sensory block level (USBL), the highest dermatome with any altered sensation to cold, and (2) lower sensory block level (LSBL), the highest dermatome with complete sensory block to cold. The purpose of this study was to further explore these sensory block levels and how they change over time with PIEB and patient-controlled epidural analgesia as a pain management method.