Final answer:
Epidural anesthesia is a regional pain-relieving drug delivered through a catheter into the lower spine that can cause severe hypotension and tinnitus.
Step-by-step explanation:
The subject of the question is anesthesia. The regional pain-relieving drug that is delivered continuously through a catheter into a small space in the lower spine is called an epidural anesthesia. The adverse effects of severe hypotension (hypoTN) and tinnitus are associated with this type of anesthesia.