1)      Ring blocks

i)        Mix 1.0 mg/kg (0.5 mg/lb) bupivacaine with 1.0 mg/kg (0.5 mg/lb) lidocaine and:

(1)   Either 0.075 mg/kg (0.035 mg/lb) morphine or 0.003 mg/kg (0.0015 mg/lb) buprenorphine may effectively double the duration of analgesia^1,2

(2)   Sterile water q.s., if needed, to total 1 cc volume for cats less than 2.5 kg (5 lb).

(3)   Sterile water q.s., if needed, to total 2 cc volume for cats 2.5 kg (5 lb) and over.

ii)       Inject subcutaneously at the three sites demonstrated below. Pinch the skin to tent it away from the deeper tissues and inject

iii)     You may drop the lidocaine if given prior to spay (gives bupivacaine time to take effect)

iv)     Bupivacaine has significant potential to cause cardiac toxicity

(1)   Calculate dose carefully

(2) Aspirate carefully before injecting

v)   DO NOT USE EPINEPHRINE CONTAINING AGENTS

Click here for an MS Excel Ring Block dose calculator