See the companion article, Nerve Blocks for Oral Surgery in Dogs

Nerve blocks for oral surgical procedures in cats provide a complete sodium channel blockade, preventing ascending pain signals that are created during surgical manipulation to reach the cerebral cortex. Because of their high surface area to body ratio, cats are particularly susceptible to hypothermia. Nerve blocks not only provide perioperative analgesia but allow inhalant anesthetic concentrations to be minimized. Doing so maximizes cardiac output, blood pressure, and overall perfusion, resulting in warmer patients.

Bupivacaine is the anesthetic of choice for oral nerve blocks because of its long duration of action (6–10 hours). Its maximum extravascular dose is determined by patient weight; a safe target maximum dose is 2 mg/kg (Table), but this dose is not commonly reached.

Table: Infusion Volume of 0.5% Bupivacaine per Site Based on Patient Weight