Summary
The efficacy of the femoral nerve block (FNB) in alleviating postoperative pain was
evaluated in dogs undergoing stifle arthrotomy. The pre- and postoperative nerve blocks
were compared to intraarticular administration of a local anaesthetic. Forty-eight
dogs with a ruptured cranial cruciate ligament were randomly assigned to the following
groups: Group A (n = 16) received a femoral perineural injection prior to surgery;
eight dogs within this group were given 0.5% bupivacaine and eight dogs received 0.9%
saline. Group B (n = 16) had a femoral perineural injection immediately after surgery;
eight dogs received 0.5% bupivacaine and eight received 0.9% saline. Group C (n =
16) dogs were given 0.5% bupivacaine (n = 8) or 0.9% saline (n = 8) intraarticularly.
Postoperative pain was evaluated using a visual analog scale and a numerical rating
scale, including measurement of heart rate, respiratory rate and systolic pressure.
The dogs were scored preoperatively and at zero to six and at 24 hours after the operation.
A significant difference was not noted between groups during the time until the first
dose of supplemental analgesia nor in the total dose of supplemental analgesia required.
The duration of the operation was found to be negatively correlated with the duration
of postoperative analgesic effect. There was not any significant difference between
the groups in pain scores at any time.
Femoral nerve block (FNB) was evaluated for the control of postoperative pain in dogs
undergoing stifle arthrotomy. FNB, using bupivacaine, was performed preoperatively
and was compared to a postoperative FNB, and to saline controls. In addition, the
efficacy of the FNB was compared to intra-articularly administered bupivacaine. Differences
were not found between any groups in the alleviation of postoperative pain.
Keywords
Canine - femoral nerve block - bupivacaine - postoperative analgesia - preemptive
analgesia
