What sign should a nurse monitor in a patient who received an epidural block for a vaginal repair?

When monitoring a patient who has received an epidural block, one of the critical signs to observe is a sudden drop in blood pressure. This is because epidural anesthesia can cause a sympathetic blockade, which may lead to vasodilation and subsequent hypotension. The anesthesia affects the sympathetic nerves that control vascular tone, resulting in decreased blood pressure.

Monitoring for hypotension is essential, as it can indicate that the nerves responsible for regulating blood pressure in response to changes in position or fluid status may be compromised due to the anesthetic's effects. Prompt recognition and intervention are crucial in managing this potential complication to ensure the patient remains stable and to prevent further adverse effects.

Other signs listed, while they may be relevant in other contexts, do not directly indicate a complication related to the administration of an epidural block in this scenario. For instance, flushing of the face and numbness of the perineum are common effects of the epidural anesthesia but do not signal a critical change in the patient's physiological status that requires immediate attention. Similarly, a complaint of thirst is not directly related to the implications of epidural anesthesia and is less critical in this monitoring context.