Hot off the press: the National Research Council’s Recognition and Alleviation of Pain in Laboratory AnimalsThe NRC’s publications on laboratory animal care articulate (usually in the most cautious language possible) the standard of care on which labs are assessed, so this new book on pain management is important.

Way back in 1970, Congress updated its Animal Welfare Act to include pain management for lab animals. The plan was that lab vets would prescribe anesthetics and analgesics for animals, confident that use of painkillers would only rarely interfere with an experiment. They set up a special reporting system, still in use today, to track those instances where a particular experiment requires that pain be left untreated.

30 years of pain management for lab animals – who needs a new book on the subject? Well, I do.

When I was a vet student in the mid-1980s, we used NO post-operative pain meds for our dog spays or most other surgeries. None. Amateur student hands performed major abdominal surgery on dogs, and then – nothing. It was only once I started my laboratory animal practice that this struck me as unacceptable, pointing out to colleagues in private pet practice that if it was illegal for me to leave lab animal surgical pain untreated, maybe they should rethink how they treated people’s pets.

We didn’t have the assortment of safe long-acting potent painkillers we have now, but with more awareness, we could have done much better even back then. Twenty years later, we still have a long way to go. Pet practitioners are much more attentive to animal pain management. So too are lab vets and scientists, but there are many barriers to using pain meds:

- Failure to diagnose subtle signs of animal pain

- Cost, inconvenience, paperwork

- Adverse side effects on animals’ health

- Adverse side effects on the course of the experiment

So this new book, despite its cautious language and distanced scientific language, advances the cause with some important statements and principles:

- Most experimental situations should not entail animal pain; “pain of ANY duration or intensity … merits consideration and potential treatment.”
- Until there’s convincing evidence to the contrary, all vertebrates (fish researchers and vets, take note) should be considered capable of suffering pain
- While painkillers may influence research experiments, so too may pain itself. It’s not enough any more to simply rule out pain medicines as sources of undesirable variability. I’ve discussed this in another post, and will elaborate on it soon.

The book also has some nuts-n-bolts recommendations for those of us working with animals, putting into this quasi-regulatory document what progressive vets have been promoting for the past decade. In the 90s, many of us had converged on using one drug, a longish (6 – 12 hours)-acting opioid (i.e., in the class of drugs with morphine, codeine, and fentanyl) drug called buprenorphine. Often, we might only give it if we saw clear signs of pain in our monkeys or mice.

The newer approach is finally enshrined in a more-or-less enforceable rulebook, its two main components:

- Combine drugs of different classes to attack pain from different angles. If I combine my buprenorphine with an NSAID (ibuprofen/aspirin type drugs) and use a local nerve-block at the site of my surgery, I can hope for drug synergy and better effect.  
- Start treating for pain up front, so that drug levels are at peak levels at the anticipated peak of the painful stimulus. The time to dose your first post-op pain medicine is PRE-op; waiting to treat pain until it’s unequivocally diagnosed is so last-century. 

We still have so much to learn about how different species show their pain, about how different drugs work for different species. As long as there are animals in labs, their pain needs serious attention, and this new little book could go a long way toward that goal. Congrats to the folks who made it happen.