Cardiac arrest: BLS, ALS, and the GP's role in Australia

What cardiac arrest actually is

Cardiac arrest is the cessation of effective cardiac output, defined by three findings: unresponsiveness, absent or abnormal breathing (gasping or agonal respirations count as absent), and absent central pulse. It is distinct from an acute coronary event, in which the heart continues to beat but a coronary artery is blocked — though myocardial infarction is one of the most common triggers of cardiac arrest.

The Australian Resuscitation Outcomes Consortium (Aus-ROC) estimates approximately 25,000–30,000 out-of-hospital cardiac arrests (OHCA) in Australia each year. National survival to hospital discharge sits around 10–15%. In the best-case scenario — witnessed collapse, bystander CPR within one to two minutes, shockable rhythm, AED applied within three to five minutes — survival rises to around 30%. Every minute of delay to defibrillation reduces survival by 7–10%.

Agonal breathing is the most critical misrecognition risk. Slow, gasping, or irregular respirations occur in the early minutes after cardiac arrest and are frequently mistaken for normal breathing, delaying the start of CPR. All clinic staff and patients with high-risk cardiovascular disease should be explicitly taught that agonal breathing means start CPR now.

A. Core clinical — the AU general-practice framework

Recognition and DRSABCD

ANZCOR Guideline 8 (2026) defines the DRSABCD sequence as the standard framework for responding to a collapsed person:

D — Danger. Assess scene safety before approaching. Ensure there is no ongoing electrical, traffic, or environmental hazard that could injure the rescuer.

R — Response. “Are you OK?” — firm tap to both shoulders and a call at normal voice. No response → proceed to arrest pathway.

S — Send for help. Call 000 and send a second person to retrieve the nearest AED. In adult collapse from a presumed cardiac cause, call before starting CPR — defibrillation is the priority. For paediatric collapse, drowning, or opioid-related arrest, give two minutes of CPR first, then call — these are hypoxic arrests where oxygenation is the priority.

A — Airway. Head tilt and chin lift removes upper airway obstruction in the unconscious patient. Use jaw thrust if spinal injury is suspected. Inspect the mouth and remove visible obstruction. Do not perform a blind finger sweep.

B — Breathing. Look, listen, and feel for no more than 10 seconds. Normal breathing excludes cardiac arrest; agonal gasping, absent breathing, or doubt means start CPR.

C — Compressions. For adults: rate 100–120 per minute; depth ≥5 cm (do not exceed 6 cm); ratio 30 compressions to 2 rescue breaths; allow full chest recoil between each compression; switch compressor every two minutes to maintain quality; minimise interruptions to less than 10 seconds. For children (one year to puberty): 30:2 (single rescuer) or 15:2 (two-rescuer healthcare setting); depth one-third the anteroposterior chest diameter. For infants under one year: two-thumb encircling technique (two rescuers) or two-finger technique (single rescuer).

D — Defibrillation. Apply AED pads to the bare chest — anterolateral position (right upper chest below clavicle; left mid-axillary line at V6 level). Follow voice prompts; clear everyone from the patient before the shock is delivered. Resume CPR immediately after the shock — do not check the pulse first. Repeat the two-minute CPR cycle until paramedics arrive or signs of life return.

Compression-only CPR is acceptable and encouraged for untrained or unwilling bystanders in adult cardiac arrest from a presumed cardiac cause. Lin et al. (Circulation 2011) and a subsequent Cochrane review showed equivalent neurologically intact survival in this setting, with higher overall bystander CPR rates because it removes the mouth-to-mouth barrier.

Shockable versus non-shockable rhythms

• Shockable — ventricular fibrillation (VF) and pulseless ventricular tachycardia (pVT): treated by defibrillation; the best survival rates occur when the shock is delivered within the first few minutes of arrest.
• Non-shockable — asystole and pulseless electrical activity (PEA): no shock is delivered; priorities are high-quality CPR plus identification and treatment of a reversible cause.

Reversible causes — the 4 Hs and 4 Ts

ANZCOR Guideline 11.2 and eTG (Cardiac arrest) both recommend systematically considering reversible causes throughout every resuscitation:

4 Hs: Hypoxia (asphyxia, airway obstruction, opioid overdose, severe asthma or COPD); Hypovolaemia (massive haemorrhage, ruptured aortic aneurysm, ectopic pregnancy, septic distributive shock); Hyper- or Hypokalaemia and other metabolic disturbances (DKA, uraemia, hypoglycaemia, hypocalcaemia, severe acidosis); Hypo- or Hyperthermia.

4 Ts: Tension pneumothorax (trauma, asthma, central line complication); cardiac Tamponade (post-MI free-wall rupture, pericarditis, malignancy); Toxins (tricyclic antidepressants, beta-blockers, calcium-channel blockers, opioids, local anaesthetic, cocaine, organophosphate); Thromboembolism (massive pulmonary embolism or acute myocardial infarction).

Treating the underlying cause in parallel with CPR — with bedside ultrasound, arterial blood gas, glucose, electrolytes — is what converts a non-shockable, poor-prognosis arrest into a survivable one.

Advanced life support additions

When paramedics or a trained hospital team arrives, ALS adds the following to continuous high-quality CPR per ANZCOR Guideline 11.5:

• Airway — supraglottic device (laryngeal mask airway, i-gel) then endotracheal intubation by a skilled operator; continuous waveform capnography to verify placement and assess CPR quality. End-tidal CO₂ below 10 mmHg suggests poor CPR or futility; a sudden rise signals return of spontaneous circulation (ROSC).
• IV or IO access — intraosseous access if IV is not achievable within two attempts.
• Adrenaline 1 mg IV/IO every 3–5 minutes — after the third shock for shockable rhythms; immediately for non-shockable. PARAMEDIC2 (Perkins, NEJM 2018) showed adrenaline modestly improves 30-day survival but increases severe neurological disability at three months; ANZCOR 2026 retains it pending an alternative.
• Amiodarone 300 mg IV bolus after the third shock for refractory VF or pulseless VT; 150 mg after the fifth shock. ROC-ALPS (Kudenchuk, NEJM 2016) showed amiodarone and lidocaine both numerically superior to placebo for survival to hospital admission. Lidocaine 1–1.5 mg/kg IV is an acceptable alternative if amiodarone is unavailable.
• Magnesium sulfate IV (2 g bolus) for torsades de pointes or suspected hypomagnesaemia (ANZCOR Guideline 11.5; eTG — Cardiac arrest).
• Sodium bicarbonate 1 mmol/kg IV — reserved for hyperkalaemia, severe pre-existing metabolic acidosis, and tricyclic antidepressant overdose.
• Calcium chloride 10% 10 mL IV — hyperkalaemia, hypocalcaemia, calcium-channel blocker or beta-blocker overdose.

B. The evidence for bystander CPR and early defibrillation

Pollack et al. (Resuscitation 2018) analysed 49,000 OHCAs in the United States and found public-access defibrillation before ambulance arrival was associated with survival to hospital discharge of approximately 38%, compared with 22% when the first shock was delivered by paramedics. The survival benefit of each minute of delay to defibrillation is well established across multiple registry datasets.

Aus-ROC registry data show bystander CPR rates around 50–60% in Australian urban areas and substantially lower in regional and remote settings — a gap that translates directly to preventable deaths. Programs that improve bystander CPR rates — community training, dispatcher-assisted CPR, and public-access AED placement — are the highest-yield population-level intervention.

The Heart Foundation Heart Map is an Australian online tool that allows members of the public to locate the nearest registered AED. The GoodSAM app notifies trained community volunteer responders of nearby cardiac arrests. The GP’s role includes encouraging patients with significant cardiovascular risk, and family members who may be first to respond, to locate their nearest AED and to complete basic CPR training through the Heart Foundation, St John Ambulance, or Royal Life Saving Australia.

The evidence for compression-only CPR is particularly relevant to the GP setting. Because the majority of adult cardiac arrests are from a cardiac cause — predominantly ischaemic heart disease — and because agonal breathing is so often misidentified as normal breathing, the single most impactful public message is: if someone collapses and is not breathing normally, call 000 and push hard and fast on the centre of the chest without stopping.

C. Post-ROSC care and secondary prevention

Immediate post-ROSC management

After return of spontaneous circulation, immediate priorities are:

• 12-lead ECG — if ST-elevation or new left bundle branch block is present, emergent coronary angiography and percutaneous coronary intervention is indicated per the NHFA/CSANZ Acute Coronary Syndrome Guideline 2025.
• Oxygen — target SpO₂ 94–98%; avoid hyperoxia, which worsens cerebral injury.
• Haemodynamic support — target mean arterial pressure ≥65 mmHg; vasopressors where needed.
• Targeted temperature management (TTM) — maintain core temperature 32–36 °C for 24 hours in comatose survivors. TTM2 (Dankiewicz, NEJM 2021) showed 33 °C is equivalent in outcomes to normothermia at 36 °C; current ANZCOR and ILCOR 2025 endorse 32–36 °C with active fever avoidance.
• Glycaemic and electrolyte control, seizure management.
• Neuro-prognostication deferred ≥72 hours off sedation, using multimodal assessment — clinical examination, EEG, somatosensory evoked potentials, NSE biomarker, MRI or CT brain.

ICD referral and secondary prevention

Every survivor of VF or sustained VT cardiac arrest without a clearly reversible cause warrants cardiology review for implantable cardioverter-defibrillator (ICD) consideration — the most effective intervention for preventing sudden cardiac death recurrence. ICD criteria for primary prevention include LVEF ≤35% with NYHA class II–III heart failure on optimal medical therapy for ≥3 months. Inherited arrhythmia syndromes (long-QT, Brugada, CPVT, ARVC) and hypertrophic cardiomyopathy carry separate ICD risk thresholds; refer to cardiology and the Australian Genetic Heart Disease Registry for cascade family screening.

Cardiac rehabilitation — Cochrane meta-analysis shows approximately 20–25% mortality reduction and reduced readmission in post-cardiac-event cohorts. Enrol every survivor; telehealth delivery is available via MBS 81100 for eligible patients.

D. Australian operations

GP clinic preparedness

RACGP Standards for General Practices (5th Edition) Criterion GP5.3 requires each practice to maintain equipment and trained staff capable of managing medical emergencies. In current Australian general practice, the minimum standard is:

• In-clinic AED — mounted in a visible, accessible location; monthly self-test status documented; battery and pad-expiry register maintained; known to all staff.
• Emergency drug kit — adrenaline 1 mg/mL ampoules plus adrenaline 1:1,000 IM for anaphylaxis; salbutamol MDI with spacer; hydrocortisone; glucagon; glucose (25% or 50%); naloxone; GTN spray; aspirin 300 mg; IV fluids and giving sets; bag-valve-mask; oropharyngeal airways (range of sizes); oxygen with mask; suction; intraosseous needle if staff are trained.
• Annual BLS and ALS training for every clinical and reception staff member; ANZCOR-aligned provider; training dates and attendees documented in the practice training register.
• Resuscitation drills at least every six months — scenario-based with AED simulation, drug administration, ISBAR handover, and timed metrics; hot debrief immediately after (10–15 minutes); lessons-learned log.
• Critical-incident debrief after every code — hot debrief within 15 minutes of the event, cold debrief at one to two weeks, EAP referral offered to all involved staff.

MBS billing for post-arrest GP care

Standard consultations (MBS 23, 36, 44) are the usual items for ongoing post-arrest review.

• Prolonged or complex attendance — MBS 132/133 for comprehensive post-arrest review visits.
• GP Chronic Condition Management Plan (GPCCMP) — MBS 965/967 enables multidisciplinary coordination: cardiology, cardiac rehabilitation, psychology, dietitian. The GPCCMP replaced the former GPMP and TCA from 1 July 2025.
• Mental Health Treatment Plan — MBS 2715/2717: cardiac arrest survivors, witnesses, and clinic staff who responded to a workplace code are all at elevated risk of PTSD and adjustment disorder; offer MHTP and psychology referral routinely.
• 12-lead ECG — MBS 11700 with formal report; appropriate at post-arrest review to assess QTc, arrhythmic substrate, and residual ischaemia.
• Cardiology specialist referral — MBS 105/106.
• ATSI Health Assessment — MBS 715 — include cardiovascular risk assessment with targeted secondary prevention.

Driving restrictions

Austroads — Assessing Fitness to Drive requires a minimum six-month private vehicle off-road period for cardiac arrest survivors. Commercial vehicle restrictions are longer and depend on the underlying diagnosis and ICD status. Document the Austroads discussion and the patient’s agreement to refrain from driving in the medical record.

E. Special populations

Pregnancy (beyond 20 weeks of gestation). Apply manual left uterine displacement to relieve aortocaval compression during CPR. If no ROSC by four minutes of arrest, perimortem caesarean section is indicated immediately — the goal is delivery within five minutes to optimise both maternal and fetal survival, per the RANZCOG Maternal Cardiac Arrest Guideline. Standard ALS drug doses apply; defibrillation pad placement is unchanged.

Paediatric. Two-rescuer CPR uses a 15:2 ratio; single rescuer uses 30:2. Drug doses are weight-based: adrenaline 10 µg/kg, amiodarone 5 mg/kg IV. Reversible causes in children are weighted towards hypoxia from asphyxia, drowning, or respiratory failure rather than primary arrhythmia. Give five rescue breaths before starting compressions in suspected drowning or asphyxia.

Hypothermia (core temperature <30 °C). The guiding principle is “not dead until warm and dead.” Prolong CPR and rewarm actively — ideally with ECMO at a capable centre. Withhold adrenaline and limit defibrillation to three attempts maximum until core temperature reaches 30 °C. ANZCOR Guideline 11.10 addresses this in full.

Drowning. Give five rescue breaths before starting compressions (hypoxic aetiology); otherwise proceed with DRSABCD. Administer high-flow oxygen as soon as available. Hypothermia co-occurs with cold-water drowning; prolonged resuscitation is justified.

Toxin-induced arrest. Match the antidote to the toxin: naloxone for opioids; glucagon or high-dose insulin-euglycaemia therapy for beta-blocker or calcium-channel blocker toxicity; IV lipid emulsion 20% for local-anaesthetic systemic toxicity; sodium bicarbonate for tricyclic antidepressants; atropine plus pralidoxime for organophosphate.

Aboriginal and Torres Strait Islander patients. Cardiovascular mortality occurs at significantly younger ages in ATSI Australians compared with non-Indigenous Australians. The RACGP National Guide recommends proactive cardiovascular risk assessment through the 715 health assessment, Aboriginal Health Worker engagement, and community-based CPR training to address the rural and remote bystander CPR gap.

When to escalate

Transfer urgently to a PCI-capable hospital with ICU when:

• ROSC is achieved and the 12-lead ECG shows STEMI or new LBBB — emergent coronary angiography is required.
• The patient remains comatose post-ROSC — intensive monitoring, TTM, and neuroprognostication are beyond the GP setting.
• The underlying aetiology is unclear or unstable — suspected dissection, massive PE, refractory arrhythmia, or electrolyte emergency.
• The arrest is in a young person (under 40) — refer to cardiology and the Australian Genetic Heart Disease Registry for inherited arrhythmia and cardiomyopathy screening, and cascade family assessment.
• Staff welfare is a concern after a clinic code — refer to EAP and medical defence organisation; post-traumatic stress in first responders is common and responsive to early support.

What this article is and is not

This is general health information drawn from ANZCOR resuscitation guidelines, Therapeutic Guidelines, RACGP Standards, and major cardiac arrest trials. It is not personal medical advice and does not create a doctor–patient relationship. Resuscitation guidelines are reviewed regularly; practitioners should maintain currency through accredited BLS and ALS training with an ANZCOR-aligned provider.

For Australian consumer-friendly information on cardiac arrest and CPR: HealthDirect — Cardiac arrest, Better Health Channel, and Heart Foundation.

For immediate emergency: call 000.

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Sources cited

1. ANZCOR Guidelines for Cardiopulmonary Resuscitation and Advanced Life Support 2026
2. Therapeutic Guidelines — Cardiac arrest and cardiac arrhythmias
3. Australian Medicines Handbook — Cardiovascular emergencies
4. RACGP Standards for General Practices 5th Edition
5. Aus-ROC Australian Resuscitation Outcomes Consortium registry
6. Heart Foundation — AED Heart Map and cardiovascular disease risk 2023
7. NHFA/CSANZ — Australian Clinical Guideline for Acute Coronary Syndromes 2025
8. Perkins GD et al. — PARAMEDIC2 adrenaline trial (NEJM 2018)
9. Kudenchuk PJ et al. — ROC-ALPS amiodarone vs lidocaine vs placebo (NEJM 2016)
10. Dankiewicz J et al. — TTM2 targeted temperature management (NEJM 2021)
11. Lin S et al. — Compression-only vs standard CPR (Circulation 2011)
12. Pollack RA et al. — Public-access AED and survival (Resuscitation 2018)
13. RANZCOG — Maternal cardiac arrest guideline
14. Austroads — Assessing Fitness to Drive
15. Australian Genetic Heart Disease Registry
16. RACGP National Guide to a preventive health assessment for Aboriginal and Torres Strait Islander people
17. HealthDirect — Cardiac arrest
18. Better Health Channel — Cardiac arrest and CPR