A client is receiving an epidural anesthesia during labor. Which observation is the most important adverse effect that the practical nurse (PN) should assess for following the administration of the epidural?

A. Maternal hypotension: Epidural anesthesia can cause sympathetic nerve blockade, leading to vasodilation and a significant drop in blood pressure. Maternal hypotension is the most critical adverse effect because it can reduce uteroplacental perfusion, affecting fetal oxygenation and requiring immediate intervention. B. Continuous headache: Post-dural puncture headache may occur if there is a dural puncture, but it is less immediate and not life-threatening compared with hypotension. Monitoring and interventions for headache are important but secondary. C. A vaginal hematoma: Vaginal hematomas are unrelated to epidural anesthesia and are more commonly associated with trauma during delivery. While they require attention, they are not a direct adverse effect of the epidural. D. Urinary retention: Epidural anesthesia can impair bladder sensation, leading to urinary retention. Although this requires monitoring and potential catheterization, it is not as urgent as maternal hypotension.