Archive for Sunday, December 8, 2002

Owners be wary when anesthesia is used on pets

December 8, 2002


It's time for your kitten to be spayed, or your elderly dog to undergo a much- needed teeth cleaning. At the vet's office, you watch Fluffy disappear behind a door, hopefully to re-emerge a few hours later, a little groggy but good as new.

While most dogs and cats are tolerant of anesthesia, each time it is used there is a risk, however small. All the more reason why, when it comes any procedure involving anesthesia, your consciousness matters. Some factors to consider:

Pre-op exams

"I've had people say they favor a certain practice because the vet doesn't charge for exams," says Alicia Z. Karas, assistant professor of clinical sciences and a board- certified anesthesiologist at Tufts University School of Veterinary Medicine in North Grafton, Mass.

That kind of thinking is shortsighted, she says. "A thorough exam, even of young dogs and cats, is important," allowing the vet to pick up abnormalities such as a heart murmur or signs of anemia. Simple blood tests also can identify risk factors and are especially important for older animals.


It's a legitimate question to pose to your vet: Who will observe my animal while you perform surgery?

"Having somebody watch the animal, his respiration and some form of monitoring of his heartbeat - that's number one," says Arnold Lesser, a board-certified orthopedic surgeon based on Long Island.

Many practices have electrocardiographs and pulse-oximeter machines, which measure oxygen saturation in the blood. In addition to inquiring about who will be attending the vet during surgery, Lesser says it's "fair" to ask if a vet will use those two pieces of equipment.

While Karas says shorthanded practices might use monitoring equipment as a substitute for having a person there, "pulse-ox and EKG can give you misleading information. If you had a human being listening for heart and breath sounds, that would be best."

Simultaneous human and mechanical monitoring is optimal - as is an observer who has some training in anesthesia, although in many practices, the vet tech fulfills this role capably.

In specialty practices, or very progressive ones, animals might receive intravenous fluids during surgery to maintain blood pressure and hydration. These vets also might have additional monitoring equipment, such as a blood-pressure monitor.


There are two categories of anesthesia: "induction" and "maintenance." Induction anesthesia is injected to get the animal unconscious. Today, many vets still use a combination of Ketamine and Valium. The newest injectable agent, Propofol, is quicker-acting, but it can depress breathing, and it is significantly more expensive.

In the past, ultra-short-acting barbiturates were common induction agents, but are rarely used now. Still, owners of sighthounds such as greyhounds and whippets, which have low percentages of body fat and thus cannot metabolize barbiturates well, might want to inquire to be sure.

During surgery, an animal is kept unconscious with a "maintenance" anesthetic, which is inhaled. Isoflurane is commonly used in many practices. Sevoflurane, which is relatively new, and correspondingly expensive, is especially fast-acting - a double- edged sword if a practitioner is not paying close attention.

For a quick surgery, such as a cat spay, some vets might be tempted to use just an induction anesthetic. But with the exception of cat neuters, owners should insist on inhalant anesthesia as well, because the animal is intubated - something that's invaluable if the unexpected happens. "If there is a problem, say a bad reaction, having an airway established beforehand is a big safety factor," Lesser says.

There might be situations when a veterinarian opts to skip induction anesthesia and "mask down" an animal with an inhalant anesthetic. The advantage is that the animal recovers very quickly, a plus with the very frail or sick; the disadvantage is that the masking can cause the animal to panic and stress before "going under."

Pain management

Just because some procedures, such as spays, are common, doesn't mean that they aren't painful. Yet many animals are expected to walk away without being given anything for their discomfort.

Times, however, are a-changing. "Pain management is something people are paying more attention to," Karas says. While some vets might tell clients that their animals "don't need" medication to control pain, "vet students are graduating from vet school who wouldn't consider not offering it."

With the exception of dentistry, teeth cleaning and wart removal, most animals should require at least one post-operative dose, Karas says. "Pain," she points out, "serves no useful function."

Since old habits die hard, you might have better luck seeking out a progressive-minded vet than trying to convince one who is too set in his or her ways to provide an opioid or mild narcotic.

Common sense

In the end, the old adage applies: You get what you pay for. All the pluses, from well- trained staffers to sophisticated monitoring equipment to the type of anesthesia itself, come at a price. Bargain-hunting is fine if you're at Kmart " but not at your vet's office.

Commenting has been disabled for this item.