Which of the following reflects complications of an epidural block?

The correct choice highlights complications that can directly arise from an epidural block. Hypotension is a well-documented consequence of epidural anesthesia due to sympathetic blockade, which leads to vasodilation and decreased systemic vascular resistance. High spinal paralysis may occur if the anesthetic spreads too high in the spinal column, affecting the nerves that control respiratory function and causing significant impairment. A spinal headache, or post-dural puncture headache, can result if the dura mater is punctured during the procedure, leading to a leak of cerebrospinal fluid and causing a headache that typically worsens in an upright position.

Other options include complications that either do not directly relate to the epidural block or are more general issues not specific to this type of anesthesia, such as nausea and dizziness or systemic reactions like fever and infection. These can occur in various surgical contexts but are not unique to or primarily associated with the use of epidural blocks. The focus on hypotension, high spinal paralysis, and spinal headache in the correct choice captures the most relevant complications associated specifically with epidural anesthesia.