Revised CPR guidelines in dogs, cats emphasize speed, standard techniques

RECOVER Initiative updates document with a streamlined CPR algorithm and new drug dosing charts

Updated July 11, 2024

Any veterinary patient undergoing anesthesia is at risk of cardiopulmonary arrest.

Dr. Daniel Fletcher, associate professor in the emergency and critical care section at Cornell University College of Veterinary Medicine, said, “You don’t see (cardiopulmonary) arrest that often, but in general practice settings it’s usually around anesthesia, and there’s a lot of reason to think you can get these patients back” with cardiopulmonary resuscitation (CPR).

Research on cardiopulmonary arrest (CPA) epidemiology has shown that, in veterinary medicine, the return of spontaneous circulation (ROSC) after CPA was 35%-55% compared with 61% in human medicine.

Two veterinarians perform CPR on a large dog
Dr. Daniel Fletcher, co-chair of the Reassessment Campaign on Veterinary Resuscitation (RECOVER) Initiative, which recently released updated guidelines for CPR in dogs and cats, noted that one approach doesn’t work equally well in all breeds and should be tailored to the patient. The types of chest conformations and approaches for each are included in the revised guidelines. (Photos courtesy of the RECOVER Initiative)

Further, the survival to discharge rate is 6%-19% in veterinary medicine versus 25% for human medicine.

“The important thing to keep in mind is this is across all patients who arrested in tertiary referral facilities,” said Dr. Fletcher. “Patients that arrested around anesthesia were 17 times more likely to survive to discharge, and cats were five times more likely to survive than dogs” because it’s easier to do chest compressions on them.

To improve survival rates, he said, there has to be good anesthesia monitoring. But also, “You have to think of the chain of survival. It’s not just about CPR but being prepared and preventing arrests before they occur.” Then, once the patient has achieved return of spontaneous circulation, managing them in the post-cardiac arrest (PCA) period.

Human medical professionals are required to certify in CPR, but there is no such requirement in veterinary medicine. The Reassessment Campaign on Veterinary Resuscitation (RECOVER) Initiative aims to set that standard and empower veterinary professionals to stand tall knowing they gave their patients the best chance possible.

On June 26, the RECOVER Initiative unveiled the first major revisions to its global veterinary CPR guidelines since 2012, setting new life-saving standards based on scientific advancements and extensive community feedback.

Notable changes

The primary goal of the RECOVER 2024 CPR Guidelines is to improve CPR outcomes in veterinary patients, mirroring the advancements seen in human medical care through the broad acceptance of evidence-based CPR guidelines. These guidelines, training courses, and an official certification process underscore the importance of preparedness in emergency situations, particularly in general practice settings where reversible causes of cardiopulmonary arrest, such as anesthesia-related issues, present opportunities to save lives.

The revised guidelines are available in an open-access issue of Wiley’s Journal of Veterinary Emergency and Critical Care and at the RECOVER Initiative website.
Key updates include the following:

  • Chest compression techniques: Enhanced methods for cats and small dogs to optimize survival during cardiac arrest.
  • Compression depths and techniques: Adjustments tailored to an animal's size and chest shape, improving CPR effectiveness.
  • Breathing support methods: Revised for non-intubated patients, focusing on rescuer safety.
  • Medication dosages and procedures: Updated for more precise and effective treatment during CPR.

In addition, a new streamlined CPR algorithm, updated drug dosing charts, and an ECG diagnosis algorithm have been included to help standardize CPR practices globally.

Graphic chart displaying CPR algorithm for dogs and cats
The RECOVER Initiative included a CPR Algorithm for Dogs and Cats in its updated guidelines. (Courtesy of RECOVER)

Dr. Fletcher, co-chair of RECOVER, gave a presentation on the updated guidelines at the 2024 Veterinary Meeting & Expo, held January 13-17 in Orlando, Florida.

He said the CPR initial assessment algorithm, available for download on the resources page of the RECOVER Initiative website, should be used to help determine if and when to perform CPR, which shouldn’t take more than 10-15 seconds.

“The unresponsive patient is the scariest to me, and I need to quickly figure out if they’re alive,” Dr. Fletcher added.

The first step is to stimulate by shaking and shouting, and then see if they are breathing. If the animal is not breathing, the responder should find other people to help, if possible.

“There’s nothing about checking a pulse,” Dr. Fletcher said. “We still know it’s not the most sensitive measure and it’s a poor way to diagnose CPA.”

He said for basic life support, the most important parts are quality chest compressions and making sure the patients are ventilated.

One person should start chest compressions, and another should evaluate the airway to make sure it’s not obstructed and get them intubated to start ventilating. If you’re alone, Dr. Fletcher said to first check to see if the airway is clear. If it is, start chest compressions, but if not, clear it and then start single-rescuer CPR.

For the chest compressions, the guidelines recommend being positioned behind the patient’s spine while on their side in most cases. Responders should have one hand on top of the other with fingers interlaced, making sure not to spread their hands apart or have the heels of the hands separated for good compression posture. This allows the force of the compression to be focused on the location of the heel of the hand touching the chest. Shoulders should be directly above the hands, elbows should be locked, and the person should bend at the waist and engage core muscles.

That said, Dr. Fletcher noted that one approach doesn’t work equally well in all breeds and should be tailored to the patient. The types of chest conformations and approaches for each are as follows:

  • Large, round-chested dogs have a lot of tissue around the ventral chest wall, making it difficult to directly compress the heart. Therefore, responders should focus their compressions over the widest part of the chest. This location is most easily found by feeling the chest with the dog in lateral recumbency. Feel for the dome shape of the chest, characteristic of round-chested dogs, and focus the compression on the highest point on the dome.
  • It’s easy to directly compress the heart in large keel-chested dogs, such as Greyhounds, because there’s not as much tissue around the ventral body wall. When feeling the chest of a keel-chested dog in lateral recumbency, responders will note a gradual rise in the chest as they move their hands from ventral to dorsal, almost like a ski slope. To find the location of the heart quickly, rotate the patient’s elbow one-third of the distance between the sternum and the spine and focus your compressions on the location of the elbow.
  • Wide-chested dogs, such as some English Bulldogs, have chests that are wider than they are deep. Chest compressions should be done over the sternum with the dog in dorsal recumbency, not lateral, allowing compression of the heart between the sternum and the spine. Further, an updated recommendation is to perform chest compressions to 25% depth, rather than 33%–50%, when a patient is in dorsal recumbency. The guidelines note that if responders think a dog is wide-chested but will not easily stay in dorsal recumbency, it is likely better to do compressions as recommended for round-chested dogs.
  • Cats and small breed dogs have chests that tend to have more compliant chests than large breed dogs, so even if they have a more rounded chest, the focus should be on compressing directly over the heart.

Regarding cats and small dogs, Dr. Fletcher said, “In the new guidelines, we’re no longer recommending a two-hand approach in this group because of the high likelihood of injuring the chest, but we’re recommending three other approaches: the previous one-hand technique, circumferential compressions, or a one-armed technique.” Diagrams and more detailed explanations of these new approaches are in the updated guidelines.

The other important component of basic life support in animals—ventilation—has also been updated in the new guidelines. Whenever feasible, dogs and cats should be intubated with a cuffed endotracheal tube as soon as possible, while compressions are ongoing.  

Breaths should be delivered at a rate of 10 breaths per minute and a 1-second inspiratory time during CPR, targeting a tidal volume of approximately 10 mL per kg. Chest compressions should be delivered in uninterrupted cycles of 2 minutes, after which a new responder should rotate in to reduce fatigue and ensure good quality chest compressions are maintained, Dr. Fletcher said.

If intubation is not possible, using a manual resuscitator bag and tight-fitting face mask is recommended in the new guidelines rather than the mouth-to-snout technique because of concerns around zoonotic disease transmission.

The guidelines say it is best to use masks that don’t have vents—or to occlude the vents when delivering the breaths—and to only use masks with rubber gaskets to make a good seal. If this type of equipment is not available, and there is any possibility of zoonotic disease in the patient, the guidelines recommend compression-only CPR.

A cat receives CPR via defibrillator
The 2024 version of the RECOVER CPR guidelines recommend defibrillation precedes the use of epinephrine for dogs and cats with shockable rhythms.

For patients that are not intubated, the guidelines recommend a compression-to-ventilation ratio of 30 chest compressions to two breaths.

Lastly, the guidelines recommend that CPR drugs be administered via an intravenous catheter rather than an intraosseous catheter if possible.

“If attempts at IV access are not successful within 2 minutes, we suggest that rescuers pursue IO catheter placement and to concurrently attempt to secure IV and IO access if adequate personnel are available,” the document states.

Adoption and education

Experts worldwide and across disciplines collaborated on developing the treatment recommendations. The 2024 RECOVER CPR guidelines were generated used a modified version of the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) system for guidelines creation in health care. Most human clinical guideline organizations use this approach, including the International Liaison Committee on Resuscitation, which produces human CPR guidelines.

“Thanks to a rigorous review of over 1,370 studies by 102 volunteer evidence evaluators, these updates embody our commitment to the highest standards of evidence-based veterinary practice,” said Dr. Jamie Burkitt, the other co-chair of RECOVER, in the press release.

The RECOVER Initiative, founded by the American College of Veterinary Emergency and Critical Care and the Veterinary Emergency and Critical Care Society, calls on veterinary professionals and pet owners alike to adopt the practices outlined in the updated document to enhance acute care outcomes for pets and ensure the best possible results.

Enhanced training courses approved by the American Association of Veterinary State Boards’ Registry of Approved Continuing Education are set to equip 400 RECOVER certified instructors worldwide to certify veterinary professionals in performing these life-saving techniques.

Further guidelines on newborn resuscitation, prevention and preparedness, and first aid are expected in the near future.