Final answer:
Regional anesthesia is associated with decreases in pain sensation in a specific body region, the need for general anesthesia, and the risk of postoperative nausea and vomiting, but it does not affect blood pressure during surgery.
Step-by-step explanation:
The use of regional anesthesia is associated with decreases in all of the following except blood pressure during surgery. Regional anesthesia is a type of anesthesia that blocks pain sensation in a specific body region. It is commonly used to reduce the need for general anesthesia and the risk of postoperative nausea and vomiting. However, it does not have a direct effect on blood pressure.