View Full Version : total hip surgeries on an animal model

06-12-1996, 11:04 PM
On Wed, 12 Jun 1996, Brent G. Parks wrote:
> We are gearing up to conduct an investigation of a newly designed femoral
> component of a total hip joint in an animal model (sheep). Preferably, we
> reviewed thus far reported unilateral surgeries. A second concern is
> medication post-op. Any guidance regarding ambulation after bilateral
> surgeries and administration of pain medications post-op would be greatly
> appreciated.

Analgesics in sheep: a variety of techniques can be used. Remember to give
the analgesics during surgery or even before, as a premed, in order to get
the benefits of pre-emptive analgesia.

1) Systemic opiates: sheep do well on most opiates. Morphine is cheap and
effective for immediate post-op pain, for lower grade pain later on
butorphanol and buprenorphine are good.

2) Non-steroidal anti-inflammatories give good analgesia. They can be
mixed with opiates or used on their own for mild to moderate pain. The
combination of NSAIDs and opiates is very effective. Flunixin has been
used a lot in sheep. Carprofen is also popular (less tendency to cause ulcers)
but difficult to get hold of in NA.

3) Consider epidural analgesia. This, IMHE, is very effective in dogs
undergoing hip replacement. The choices are to use local anaesthetics,
opiates or alpha-2 adrenergic agonists. Local anaesthetics are only of use
during sx as you want the sheep to stand afterwards, but they will reduce
the amount of anaesthetic needed considerably as the whole back end is
blocked out. You will also get useful pre-emptive analgesia. Epidural
opitates (morphine and oxymorphone are the most widely used) give very
good, long-lasting analgesia with no interference with motor control. You
can mix a short-acting local analgesia (e.g. lidocaine) with opiate and give it
in one injection. There have been some trials of epidural alpha-2 agonists in
sheep but results are still mixed.

I've attached some recent correspondence on other lists about sheep

Simon Young


Also FYI for sleep analgesia: check out the work by Eisenach and
especlally re: spinal analgesia. may be even better for pregnant ewes and
concerns about fetus due to less systemic and placental transfer of
analgesic. here are a few refs I've seen:

1. Eisenach, J.C., Dewan, D.M., Rose, J.C., and Angelo, J.M. Epidural
clonidine produces antinociception, but not hypotension, in sheep.
Anesthesiology 66:496-501, 1987.

2. Detweiler, D.J., Eisenach, J.C., Tong, C., and Jackson, C. A
interaction in alpha 2 adrenoceptor-mediated antinociception in sheep.
J.Pharmacol.Exp.Ther. 265:536-542, 1993.


Craig W. Stevens, Ph.D. internet: stevens@vms.ocom.okstate.edu
Associate Professor of Pharmacology FAX: 918-561-8412
OSU-College of Osteopath Medicine Ph: 918-561-8234
1111 West 17th Street
Tulsa, OK 74107-1898


We have been using since more than 2 years buprenorphine (Temgesic)
every 8 hrs in pregnant sheep after operations on the foetus and in goats
after cardiac or orthopaedic surgery with apparently good results and no
unwanted side effects.
Sincerely yours,
Ton van den Bogaard