Cardiopulmonary Resuscitation (CPR) in Animals

Definitions and Causes:

• Cardiopulmonary Arrest (CPA): Sudden cessation of effective blood circulation and breathing.

• Causes: Cardiac arrhythmias, severe hypovolemia, trauma, anesthesia complications.

Symptoms and Clinical Changes:

• Signs of CPA: Unresponsiveness, apnea, absence of palpable pulse or heartbeat.

• Clinical Changes: Hypoxia, acidosis, hyperkalemia.

Diagnostics:

• ECG: Characterizes arrhythmias.

• End-tidal CO₂ (ETCO₂): Assesses CPR quality and confirms intubation.

Basic Life Support (BLS):

• Chest Compressions: 100–120 compressions/min, 1/3 to 1/2 thoracic width.

• Ventilation: 10 breaths/min, 10 mL/kg volume.

Advanced Life Support (ALS):

• Drugs: Epinephrine (vasoconstrictor), atropine (anticholinergic), vasopressin (vasopressor), lidocaine (antiarrhythmic).

• Defibrillation: Used for ventricular fibrillation and pulseless ventricular tachycardia.

Medications and Dosages:

• Epinephrine: 0.01 mg/kg IV.

• Atropine: 0.04 mg/kg IV.

• Vasopressin: 0.8 U/kg IV.

• Lidocaine: 1–2 mg/kg IV.

Mechanism of Action:

• Epinephrine: Increases myocardial and cerebral blood flow.

• Atropine: Reduces vagal tone.

• Vasopressin: Vasoconstriction independent of adrenergic receptors.

• Lidocaine: Stabilizes cardiac membranes.

Monitoring and Post-CPA Care:

• ETCO₂: >15 mmHg indicates ROSC.

• ECG: Monitors arrhythmias.

• Post-CPA Care: Monitor for rearrest, treat underlying causes, manage acidosis and electrolyte imbalances.

For more detailed information, visit the Merck Veterinary Manual.

www.merckvetmanual.com