Cardiopulmonary Resuscitation in Dogs and Cats: An Evidence-Based Clinical Guide

Cardiopulmonary Resuscitation (CPR) in Dogs and Cats

Evidence-based, practice-ready guidance for busy small-animal clinicians

DVM Paola Moreno Estanol

Why this matters

Even perfectly run hospitals will face unexpected cardiopulmonary arrest (CPA). Survival to discharge remains modest in veterinary patients, but outcomes improve when teams recognize arrest rapidly, deliver high-quality basic life support (BLS), layer advanced life support (ALS) without delays, and provide structured post–cardiac arrest (PCA) care. The RECOVER initiative (2012; major update 2024) is the profession’s gold-standard, evidence-based framework and underpins this article.

Rapid recognition of CPA (don’t wait—treat)

Assume CPA in any unresponsive, apneic (or agonal) patient with absent pulses/heart sounds. Do not spend >5–10 s “confirming” arrest—start compressions, secure an airway, ventilate, and attach monitoring as the team assembles. Pulse palpation is unreliable during compressions; rhythm checks should occur in ≤10 s pauses every ~2 min. Today's Veterinary Practice

Basic Life Support (BLS)

Compressions (the single biggest determinant of success)

• Position: Lateral recumbency for most dogs/cats; consider dorsal (sternal compressions) in barrel-chested breeds. Keel-chested and cats/small dogs benefit from “cardiac-pump” hand placement directly over the heart. AAHA

• Rate & depth: 100–120/min, compress ⅓–½ thoracic width, allow full recoil, minimize interruptions; rotate compressors every 2 min.

• Cycle: Uninterrupted 2-minute cycles with ≤10 s rhythm checks; resume immediately if no ROSC. recoverinitiative.org

Airway & Breathing

• Intubate promptly without stopping compressions; if delayed, use mouth-to-snout breaths.

• Ventilate with 100% O₂ at ~10 breaths/min (1 breath q6 s; ~10 mL/kg tidal volume; ~1-s inspiratory time). If not intubated, use 30:2 compression-to-ventilation ratio. Avoid hyperventilation.

Advanced Life Support (ALS)

Vascular access & drug routes

• IV preferred; IO if IV is not immediately available.

• Intratracheal dosing (diluted) is acceptable when IV/IO cannot be obtained (e.g., NAVEL drugs). Intracardiac injections are discouraged outside open-chest CPR.

Vasopressors & vagolytics

• Epinephrine (low dose): 0.01 mg/kg IV/IO q3–5 min remains first-line; routine “high-dose” epi is no longer recommended in the 2024 update except select, prolonged scenarios.

• Vasopressin: 0.8 U/kg IV/IO may be used as an alternative/adjunct per clinician preference and patient acid–base status.

• Atropine: 0.04 mg/kg IV/IO in asystole/PEA or suspected high vagal tone.

Shockable rhythms & antiarrhythmics

• Defibrillation: Treat VF/pulseless VT with a single shock then immediate compressions; biphasic ~2–4 J/kg (increase if persistent). Avoid stacked shocks.

• Amiodarone (refractory VF/VT): ~5 mg/kg IV; Lidocaine alternative 2–4 mg/kg IV when amiodarone unavailable.

Monitoring during CPR

• ECG for rhythm diagnosis only during planned ≤10 s pauses.

• Capnography: Continuous ETCO₂ guides CPR quality and heralds ROSC (a sudden jump often precedes palpable pulses). Aim for ETCO₂ ≥15 mmHg during compressions.

Reversible causes (fix while you compress)

Think “Hs & Ts” adapted to vet practice: hypoxemia, hypovolemia/hemorrhage, hydrogen ion (acidosis), hyper/hypokalemia (e.g., blocked cat/Addisonian crisis), hypoglycemia, hypothermia/hyperthermia, tension pneumothorax, tamponade, thromboembolism, toxins (incl. anesthetics—reverse early). Thoracocentesis, pericardiocentesis, insulin/dextrose + calcium, decontamination/antidotes, and active cooling/warming are often decisive.

Open-chest CPR (select cases)

Consider in giant breeds, severe pleural/pericardial disease, major thoracic trauma, or refractory arrest when external compressions are ineffective and surgical capability exists; enables internal massage and internal defibrillation.

Post–cardiac arrest (PCA) care

Most losses occur after ROSC. Treat PCA as a complex, multi-organ syndrome: stabilize hemodynamics, optimize oxygen delivery, control temperature, protect the brain, and prevent rearrest.

• Perfusion: Target adequate MAP (direct/invasive BP ideal); individualized fluids (avoid overload), vasopressors (norepinephrine/dopamine) for hypotension; dobutamine for myocardial stunning/low output. Trend lactate and correct electrolytes/acid–base disorders. PubMed

• Ventilation/Oxygenation: Maintain normocapnia and avoid both hypoxemia and prolonged hyperoxia; titrate FiO₂ to keep SpO₂ ~94–98%.

• Neuroprotection & temperature: Avoid hyperthermia; consider targeted temperature management (mild hypothermia) in comatose patients where resources permit; control seizures aggressively.

• Monitoring: Continuous ECG and BP; capnography for ventilated patients; frequent blood gases, glucose, electrolytes; urine output; serial neuro checks. Structure nursing care (turning, eye lube, analgesia, sedation as needed) and begin nutrition once stable.

Prognosis, communication, and code logistics

Survival to discharge is markedly lower than in people, but improves in witnessed/anesthetic arrests and when CPR is delivered fast and skillfully. Discuss code status (Full Code vs DNR) with owners for all ICU/high-risk/anesthetized patients. Maintain a standardized crash cart, dosing charts, CPR record sheets, and run regular mock codes (team roles: compressor, ventilator, drug nurse, recorder, leader). RECOVER certification for vets and techs improves readiness and standardization.

Practical quick-use doses & numbers (for context while you build your in-clinic chart)

• Compressions: 100–120/min; depth ⅓–½ chest; lateral recumbency (most).

• Ventilation (intubated): ~10/min; ~10 mL/kg; avoid hyperventilation.

• Epinephrine: 0.01 mg/kg IV/IO q3–5 min (low-dose standard per 2024).

• Atropine: 0.04 mg/kg IV/IO in asystole/PEA/high vagal tone.

• Vasopressin: 0.8 U/kg IV/IO (alternative/adjunct).

• Defibrillation (VF/pVT): biphasic ~2–4 J/kg, single shock → compress.

• Capnography goal during CPR: ETCO₂ ≥15 mmHg (higher ROSC likelihood).

References

1. RECOVER Initiative – 2012 guidelines hub. Algorithms, evidence base. recoverinitiative.org

2. RECOVER Initiative – 2024 guidelines landing & JVECC supplement. Updated BLS/ALS/Monitoring recommendations.

3. AAHA NewStat (Jan & Sept 2024). Practical updates (positioning; compression rate/depth; early ventilation; de-emphasis of high-dose epi).

4. AVMA News (July 2024). Overview of the first major RECOVER revision since 2012. avma.org

5. Clinician’s Brief (CPR overviews). At-a-glance clinical protocols/checklists.

6. RECOVER – 2024 algorithms & drug charts (downloadable visuals for clinics). recoverinitiative.org

7. Post-cardiac arrest care (JAVMA and related reviews): targets for MAP/SpO₂/ventilation; neuroprotection. PubMed

8. Feline-focused CPR review (J Feline Med Surg). Species-specific nuances. PMC

9. Angell/MSPCA PCA guidance (clinical summary): inotropes/arrhythmia management tips.

10. TVP. CPR for Dogs and Cats: The RECOVER Guidelines for Veterinary Resuscitation.

11. AVMA. Revised CPR guidelines in dogs, cats emphasize speed, standard techniques RECOVER Initiative updates document with a streamlined CPR algorithm and new drug dosing charts.

12. AAHA. How to safe a life. 2024.

13. Clinician's Brief. Guidelines for CPR in Dogs & Cats.