Start strong

• Begin CPR, provide bag-mask ventilation with oxygen and attach the monitor/defibrillator.
• Compress at 100–120/min, at least 2 inches (5 cm) deep, with complete recoil.
• Minimize interruptions; change compressors every 2 minutes or sooner if fatigued.

Rhythm pathway

• VF/pVT: shock, immediately resume CPR for 2 minutes, obtain IV/IO access and repeat rhythm checks.
• PEA/asystole: epinephrine as soon as possible, CPR for 2 minutes and treat reversible causes.

Key medications

Epinephrine 1 mg IV/IO every 3–5 min Amiodarone 300 mg, then 150 mg Lidocaine 1–1.5 mg/kg, then 0.5–0.75 mg/kg

Ventilation

No advanced airway: 30:2. With an advanced airway: continuous compressions plus 1 breath every 6 seconds; use waveform capnography when available.

Recognize

Bradyarrhythmia is typically a heart rate below 50/min. Determine whether it is causing cardiopulmonary compromise.

Signs of compromise

• Hypotension
• Acutely altered mental status
• Signs of shock
• Ischemic chest discomfort
• Acute heart failure

Immediate support

• Maintain the airway; give oxygen and assist ventilation when needed.
• Attach a cardiorespiratory monitor and monitor the pulse.
• Identify and treat the underlying cause.

Treatment when compromise persists

Atropine 1 mg IV Repeat every 3–5 min Maximum 3 mg

If atropine is ineffective: transcutaneous pacing and/or dopamine infusion 5–20 mcg/kg/min or epinephrine infusion 2–10 mcg/min. Consider expert consultation and transvenous pacing.

Assess

Tachyarrhythmia is typically a heart rate of 150/min or faster. Support the airway and breathing, give oxygen if hypoxemic, monitor ECG/BP/oximetry, obtain IV access and acquire a 12-lead ECG when available.

Unstable?

• Hypotension
• Acutely altered mental status
• Signs of shock
• Ischemic chest discomfort
• Acute heart failure

If unstable: perform synchronized cardioversion and sedate whenever feasible. Use the device-recommended energy; if unknown, use the maximum energy setting.

If stable

• Narrow, regular: consider vagal maneuvers and adenosine.
• Wide QRS ≥0.12 sec: adenosine only if regular and monomorphic; consider an antiarrhythmic infusion and expert consultation.

Adenosine 6 mg rapid IV + flush Second dose 12 mg if needed Amiodarone 150 mg over 10 min

Initial stabilization

• Assess and manage the airway; confirm advanced-airway placement.
• Use 100% FIO₂ until oxygen saturation or PaO₂ can be measured reliably, then titrate.
• Target SpO₂ 90%–98% or PaO₂ 60–105 mm Hg.
• Target PCO₂ 35–45 mm Hg unless severe acidemia is present.
• Use fluids and/or vasopressors as needed to target MAP ≥65 mm Hg.

Find and treat the cause

• Obtain a 12-lead ECG.
• Consider CT, ultrasound or echocardiography when clinically appropriate.
• Consider emergency coronary intervention for persistent ST elevation, cardiogenic shock, recurrent/refractory ventricular arrhythmias or severe ischemia.

If not following commands

• Use a deliberate temperature-control strategy with a goal of 32°C–37.5°C.
• Evaluate for seizures and obtain EEG.
• Use delayed, multimodal neurologic prognostication—generally ≥72 hours after ROSC or normothermia.

• Rate: 100–120 compressions per minute.
• Depth: at least 2 inches (5 cm) for an adult; avoid excessive depth.
• Recoil: allow the chest to return fully after each compression.
• Interruptions: keep pauses as short as possible.
• Ventilation: avoid excessive rate or volume.
• Rotation: switch compressors every 2 minutes.
• Feedback: use audiovisual feedback and capnography when available.
• After a shock: resume compressions immediately.

Hs

• Hypovolemia
• Hypoxia
• Hydrogen ion excess (acidosis)
• Hypokalemia or hyperkalemia
• Hypothermia

Ts

• Tension pneumothorax
• Cardiac tamponade
• Toxins
• Pulmonary thrombosis
• Coronary thrombosis

Team reminder

Use closed-loop communication: assign a clear task, confirm the message was heard and report when the task is complete. Reassess rhythm, CPR quality and likely causes throughout the code.