Adult cardiac arrest (ACLS)
Adult in-hospital cardiac arrest summary aligned with the 2025 AHA ACLS circular algorithm: high-quality CPR, shockable rhythm management, drugs, airway, capnography, and reversible causes.
Interactive ACLS walkthrough
Enter rhythm, then confirm each algorithm step. 2025 AHA ACLS logic — training aid only; follow local protocols.
Start CPR — oxygen, help, attach monitor/defibrillator. Then choose the rhythm below; the tool walks each algorithm step in order. Tap to confirm when your team has done that step. Use the timers below for ~2 min pauses, epinephrine, and quick logs.
Central decision (flowchart diamond)
Rhythm shockable?
VF or pulseless VT → shockable column. PEA or asystole → non-shockable column.
Timers & team log
Same screen as your step — tap to record what happened. Reminders only; not a legal record.
How these timers work
- One ~2 min reminder covers compressor swap and rhythm check — often the same brief pause.
- After a logged shock, that timer uses post-shock wording until ~2 min has passed.
- Epinephrine: 1 mg IV/IO every 3–5 min when access allows.
Layout follows the shockable vs non-shockable columns of the classic AHA adult cardiac arrest algorithm; intervals and drugs match current ACLS teaching (same logic as the circular diagram).
Open official AHA 2025 adult cardiac arrest circular algorithm (PDF)Scope
- Use the interactive guide at the top to walk through shockable vs non-shockable branches; the sections below are a full static reference.
- This page summarises the 2025 American Heart Association (AHA) Adult Cardiac Arrest Circular Algorithm for education and quick reference.
- In a real arrest: call for help, assign roles, use your local resuscitation trolley / checklist, and follow team leader instructions.
- Drug doses and energy settings below are as stated in the AHA circular; some institutions use slightly different protocols.
Immediate priorities
- Confirm unresponsiveness and absence of normal breathing; start CPR and send for the crash team / defibrillator.
- Attach monitor/defibrillator as soon as available; identify shockable (VF or pulseless pVT) vs non-shockable (asystole / PEA) rhythm.
- Establish IV or IO access; prepare epinephrine and airway equipment.
- Use quantitative waveform capnography when an advanced airway is in place (and to confirm ET tube position if intubated).
High-quality CPR (AHA)
- Push hard — at least 2 inches (5 cm) depth.
- Push fast — 100–120/min; allow full chest recoil.
- Minimise interruptions in compressions (especially before and after shocks).
- Avoid excessive ventilation.
- Rotate compressor approximately every 2 minutes, or sooner if tired.
- No advanced airway: 30:2 compression:ventilation ratio.
- Advanced airway in place: 1 breath every 6 seconds (10 breaths/min) with continuous compressions.
- Continuous waveform capnography: if ETCO₂ is low or falling, reassess CPR quality (and other causes of low CO₂).
Defibrillation energy (AHA)
- Biphasic: use manufacturer recommendation (e.g. initial 120–200 J); if unknown, use maximum available. Further shocks: same or higher energy may be considered.
- Monophasic: 360 J.
Shockable rhythm: VF or pulseless VT
- Deliver unsynchronised shock as soon as the rhythm is identified; immediately resume CPR (minimise pause).
- After each shock, perform about 2 minutes of high-quality CPR before the next rhythm check unless the patient shows signs of ROSC.
- Give epinephrine 1 mg IV/IO every 3–5 minutes once access is available (continue across cycles).
- For refractory VF/pulseless VT, give amiodarone 300 mg IV/IO bolus, then a second dose 150 mg if needed.
- Alternative antiarrhythmic: lidocaine 1–1.5 mg/kg IV/IO first dose, then 0.5–0.75 mg/kg for a second dose (per AHA circular).
- Consider advanced airway when appropriate; after placement, switch to 1 breath every 6 s with continuous CPR.
- Throughout: search for and treat reversible causes; optimise CPR quality using ETCO₂ and team feedback.
Non-shockable rhythm: asystole or PEA
- Continue high-quality CPR; do not defibrillate a flat line or organised rhythm without VF/pVT.
- Give epinephrine 1 mg IV/IO as soon as possible, then every 3–5 minutes.
- Consider advanced airway; use capnography to guide CPR quality and detect ROSC.
- Aggressively consider reversible causes (see below) and specific treatments (e.g. tension pneumothorax decompression).
Reversible causes (Hs and Ts)
- Hypovolemia · Hypoxia · Hydrogen ion (acidosis) · Hypo- / hyperkalemia · Hypothermia
- Tension pneumothorax · Tamponade (cardiac) · Toxins · Thrombosis (pulmonary) · Thrombosis (coronary / MI)
Return of spontaneous circulation (ROSC)
- If pulse and adequate perfusion return: transition to post–cardiac arrest care (oxygenation/ventilation targets, BP support, coronary/PCI strategy per protocol, temperature management, glucose control, investigation of cause).
- Obtain 12-lead ECG and escalate to critical care / cardiology as per local pathway.
Reference
Educational reference only. Medical disclaimer