What major adverse effect should the nurse monitor for after administering an epidural block?

Monitoring for hypotension is crucial after administering an epidural block because the procedure can lead to a significant drop in blood pressure. This occurs due to the blockade of sympathetic nerves, which can cause vasodilation and decrease the vascular resistance. The resulting hypotension can diminish blood flow to vital organs, which is particularly concerning during labor when maintaining adequate perfusion to both the mother and fetus is essential.

The risk of hypotension is increased in patients who are dehydrated or have lost blood. Therefore, it's critical for the nurse to assess the patient's blood pressure frequently and be prepared to intervene with fluid administration or medications if significant hypotension develops. Early detection and management of this adverse effect can prevent more severe complications related to reduced perfusion.

While headache, respiratory depression, and fever can also occur as complications of an epidural block, hypotension is typically the most immediate and significant risk that requires vigilant monitoring directly after the procedure.