1.1 Triage & Cardiopulmonary Resuscitation

Introduction

  • Triage refers to the systematic process of prioritising sick/injured animals based on the severity of their condition and the urgency of intervention.

  • Registered veterinary nurses (RVNs) play a critical role in recognising life-threatening issues, implementing immediate first aid measures and stabilising patients before veterinary intervention.

  • Awareness and adherence to the RECOVER Updated Guidelines for CPR (2024) are crucial for effective emergency management and improving patient outcomes.

Telephone Triage

  • The initial step in emergency management often involves assessing the urgency of a situation over the phone.

  • RVNs must employ both open-ended questions ("What happened?", "Tell me about your pet's breathing?") and closed questions ("Is your pet conscious?", "Is there any bleeding?") to gather comprehensive information efficiently.

  • Key symptoms indicating a serious, potentially life-threatening problem that warrants immediate presentation to the clinic include: severe respiratory distress, uncontrollable bleeding, collapse, unresponsiveness, severe trauma, continuous seizures or acute onset of severe pain.

  • Clients should always be encouraged to bring their pets in if any symptoms suggest a serious or rapidly worsening condition, with clear instructions on transport and initial care.

Triage Process

  • Upon arrival, an immediate and rapid assessment of major body systems is performed to identify critical conditions. This focuses on the respiratory, cardiovascular and neurological systems.

  • Simultaneously, collect essential patient details: age, breed, known allergies, current medications, past medical history, vaccination status and the immediate presenting complaint.

  • Clear, empathetic and reassuring communication with clients is vital during triage. RVNs must build rapport while transparently indicating the severity of concerns and the immediate actions being taken.

Primary Assessment

  • The primary assessment is a rapid, systematic approach aimed at identifying and addressing life-threatening conditions within seconds to minutes.

  • Key systems to evaluate:

    • Cardiovascular: Assess mentation (alert, dull, comatose), mucous membrane colour (pale, pink, cyanotic, hyperaemic), capillary refill time, heartrate & rhythm, pulse quality (strong, weak, absent).

    • Respiratory: Evaluate respiratory effort (e.g. abdominal effort, paradoxical breathing), rate, pattern and the presence of any abnormal sounds (e.g. stridor, crackles, wheezes).

    • Neurological: Quickly assess level of consciousness, mentation, pupillary light reflexes and presence of seizures or severe ataxia.

Cardiovascular Assessment

  • Mentation: A rapid indicator of cerebral perfusion; changes from alert to dull or comatose suggest hypoperfusion.

  • Mucous membrane colour: Inspect gums and conjunctiva for colour changes (pale indicates poor perfusion, pink is normal, cyanotic indicates hypoxaemia, hyperaemic indicates vasodilation/sepsis).

  • Capillary refill time: Normal CRT is <2 seconds. Prolonged CRT (>2 seconds) suggests poor peripheral perfusion; rapid CRT (<1 second) suggests vasodilation/sepsis.

  • Heartrate & Rhythm: Auscultate for rate and rhythm irregularities (e.g. arrhythmias, bradycardia, tachycardia). Palpate femoral pulses for quality and presence of pulse deficits.

  • Pulse quality: Assesses peripheral blood flow (strong and synchronous with heartbeat indicates good perfusion; weak, thready or asynchronous indicates poor perfusion or arrhythmia).

Respiratory System Assessment

  • Signs of respiratory distress: Look for increased inspiratory or expiratory effort, open-mouth breathing (in cats), orthopnoea (stretching out neck/head), paradoxical chest/abdominal movements, nostril flaring, cyanosis.

  • Respiratory rate: Count breaths per minute; normal rates vary between species and patient size. Tachypnoea (increased rate) or bradypnoea (decreased rate) can be significant.

  • Respiratory effort: Observe the degree of chest and abdominal movement during respiration. Increased effort indicates compromise.

  • Auscultation: Listen to lung fields and trachea for abnormal sounds such as crackles (fluid), wheezes (bronchoconstriction), dullness (pleural effusion).

Neurological Assessment

  • Mental status: Assess the patient's level of consciousness: alert and responsive, dull/depressed, stuporous (responds only to noxious stimuli), comatose (unresponsive).

  • Abnormalities: Look for signs such as seizures, nystagmus, head tilt, ataxia, paresis, paralysis, changes in pupil size and symmetry.

  • Signs of serious issues like persistent seizures, sudden collapse or progressive neurological deficits should always trigger immediate veterinary attention and a diagnostic work-up.

Cardiopulmonary Resuscitation (CPR)

  • CPR involves a coordinated effort of external chest compressions and artificial ventilation, it aims to restore spontaneous circulation (ROSC).

  • The current recommended compression-to-ventilation ratio for a single rescuer is 30:2; for multiple rescuers, continuous compressions are often performed with asynchronous ventilations (one breath every 6 seconds).

  • Adherence to RECOVER guidelines is paramount for effective CPR. This includes proper hand placement, compression depth (1/3 to 1/2 the chest width) and rate (100-120 compressions/minute) and monitoring techniques (e.g. end-tidal CO2) to evaluate effectiveness.

Recognition Of Cardiac Arrest

  • Cardiac arrest often stems from severe underlying conditions such as hypovolaemia (e.g. severe haemorrhage, severe dehydration), hypoxia (e.g. severe respiratory disease, airway obstruction), severe electrolyte imbalances, sepsis.

  • Important warning signs that may precede cardiac arrest include: significant changes in pulse quality or rate, sudden decreased responsiveness, agonal breathing, acute collapse.

CPR Procedures

  • Chest compressions: High-quality, continuous chest compressions are the cornerstone of CPR. Minimising interruptions is critical.

  • Ventilation: Provide positive pressure ventilation using an Ambu bag or anaesthetic machine, aiming for a tidal volume of 10-15ml/kg at 10 breaths/minute, aiming for an ETCO2 of 18mmHg. 

  • ECG monitoring: Continuous electrocardiogram (ECG) monitoring is used to identify the type of cardiac rhythm. Rhythms are classified as shockable (e.g. ventricular fibrillation, pulseless ventricular tachycardia) or non-shockable (e.g. asystole, pulseless electrical activity).

  • Defibrillation: If a shockable rhythm is identified, electrical defibrillation should be applied promptly using a defibrillator.

  • Post-resuscitation care: After ROSC, care focuses on identifying and managing the underlying cause of arrest, optimising respiratory and cardiovascular function and addressing potential secondary injuries (e.g. cerebral anoxia, reperfusion injury). Monitoring involves continuous ECG, blood pressure, blood gas analysis, neurological assessment.

Emergency Drugs

  • Epinephrine: A potent vasoconstrictor and positive inotrope used during cardiac arrest to improve coronary and cerebral perfusion. 

  • Atropine: An anticholinergic drug used for severe bradycardia or asystole that does not respond to epinephrine, by blocking vagal stimulation.

  • Amiodarone: An antiarrhythmic medication administered during cardiac arrest when a patient experiences ventricular fibrillation or pulseless ventricular tachycardia, particularly if initial defibrillation attempts were unsuccessful.

  • Other drugs such as vasopressin (in place of or in addition to epinephrine), lidocaine (for ventricular arrhythmias) and fluid boluses (for hypovolaemic shock) are administered following updated algorithms for specific indications, dosing and administration routes (IV, IO, IT).