In a unique partnership between veterinary experts and physician-scientists who study and treat cardiac arrest in humans in Penn Medicine’s Center for Resuscitation Science, the same research that is saving patients who suffer cardiac arrests will now be put to use saving the lives of beloved pets. The Reassessment Campaign on Veterinary Resuscitation (RECOVER), announced this month, provides the first evidence-based guidelines on how to best treat cardiopulmonary arrest in dogs and cats.
Among humans, the survival rate for in-hospital cardiac arrest is around 20 percent, but less than six percent of dogs and cats who experience cardiopulmonary arrest (CPA) in the hospital return home for more opportunities to curl up on their owners’ laps, play fetch in the park, and nibble at special treats. Veterinarian Manuel Boller, medical director of the translational resuscitation intensive care unit in the Center for Resuscitation Science and a senior research investigator in Anesthesia and Critical Care in Penn’s School of Veterinary Medicine, a co-chair of the effort, said the new guidelines aim to settle longstanding disagreement and confusion among veterinarians about how best to treat small animals during these emergencies.
Pet CPR training has long been available for owners who wanted to learn what to do if, say, their animal had a cardipulmonary arrest after choking. But as we noted in Penn’s press release about the new initiative, the need for formal pet-CPR guidelines became obvious when Boller and his colleagues surveyed veterinarians on how they treated dogs and cats in cardiac arrest. The results, compiled from more than 600 practitioners, showed a large amount of variation in CPR technique. “What we found was that there was really no consensus on how to do that best,” Boller said. “There may have been a cohort, for example, that recommended 60-80 compressions per minute and another that thought 120-150 compressions per minute was the right thing.”
Since it can be difficult to conduct large randomized clinical trials in pets, the field has advanced slowly during the same years that new innovations for human cardiac arrest victims such as therapeutic hypothermia have been widely adopted. So, when examining the evidence relevant for pet CPR, the RECOVER investigators found that much of the data came from studies in animals other than dogs or cats and from clinical trials in humans – in fact, the best available evidence to support a specific veterinary recommendation often consisted of findings emerging from human clinical trials. When distilling all the evidence into pet CPR guidelines, the authors noted that there are more similarities in the process of resuscitation in humans and animals – such as directives to push hard and fast during chest compressions, with minimal interruptions -- than there are differences (such as the need to perform chest compressions laterally). Another interesting observation is that many more pets’ hearts are restarted following their arrest (44 percent of cats and 35 percent of dogs) than those that ultimately survive to be discharged from the hospital, which Boller notes may indicate that post-resuscitation care – which plays a key role in preventing damage to the brain and other vital organs once blood begins pumping again -- may be similarly important for animals as it is for humans.
The guidelines capitalize on those commonalities in an effort to provide the same evidence-based care for family pets that physicians employ to save human victims of cardiac arrest, which remains one of the nation’s leading killers.
“When you look at human guidelines, they originated at some point from research done with animals, which forms the fundamental concepts to build clinical trials on,” says Boller, who is a key part of Penn’s research on the use of new techniques for cardiac arrest treatment, such as the use of cardiopulmonary bypass. “Now, what we’re doing is turning things around by using the clinical research that was conducted in humans to inform how we should do CPR to help our animals. It’s really getting something back from this process of helping humans.”