ACLS Mnemonics for Rapid Recall
Use these evidence-based mnemonics to systematically approach cardiac arrest management, ensuring you address critical interventions in the correct sequence while avoiding common pitfalls that compromise patient outcomes.
Primary Survey: CAB-D
CAB-D represents the fundamental sequence for cardiac arrest management 1, 2:
- C = Compressions: Push hard (at least 2 inches/5 cm) and fast (100-120/min) with complete chest recoil, minimizing interruptions to less than 10 seconds 1, 3
- A = Airway: Open and secure the airway, considering advanced airway placement without interrupting compressions 1, 3
- B = Breathing: Provide 1 breath every 6-8 seconds (8-10 breaths/min) after advanced airway placement 1
- D = Defibrillation: Deliver shock immediately for VF/pVT using manufacturer-recommended energy (typically 120-200J biphasic or 360J monophasic) 2, 3
Critical pitfall: The old "ABC" sequence has been replaced with "CAB" because chest compressions take priority over airway management—delays in compressions directly reduce survival 1, 3.
Reversible Causes: H's and T's
The "4H's and 4T's" mnemonic identifies potentially reversible causes of cardiac arrest, though recent evidence suggests this may need expansion 1, 4:
The 4 H's:
- Hypoxia: Ensure highest inspired oxygen concentration during CPR 1
- Hypovolemia: Consider fluid resuscitation and blood products 1
- Hypo/Hyperkalemia: Check electrolytes and treat accordingly 1
- Hypothermia: Continue resuscitation until patient is rewarmed 3, 5
The 4 T's:
- Tension pneumothorax: Decompress immediately if suspected 1
- Tamponade (cardiac): Consider pericardiocentesis 1
- Toxins: Administer specific antidotes when applicable 1
- Thrombosis (coronary or pulmonary): Consider thrombolytics or emergent catheterization 1
Important caveat: Intracranial hemorrhage and nonischaemic cardiac disorders represent significant PEA causes with prevalence equaling or exceeding classical 4H&4T etiologies, occurring in 8.3% and 6.9% of cases respectively 4. Consider adding these to your differential, particularly for PEA arrests.
Drug Administration: "LEAN"
LEAN helps remember the medication sequence during cardiac arrest 1, 2:
- L = Lidocaine: Alternative antiarrhythmic for refractory VF/pVT (1-1.5 mg/kg IV/IO first dose, then 0.5-0.75 mg/kg) 2
- E = Epinephrine: 1 mg IV/IO every 3-5 minutes throughout resuscitation 1, 2, 3
- A = Amiodarone: First-line antiarrhythmic for refractory VF/pVT (300 mg IV/IO first dose, then 150 mg) 2, 3
- N = No vasopressin alone: Vasopressin as sole vasoactive drug has been removed from the algorithm 1
Key timing: Administer epinephrine early in non-shockable rhythms, but after initial defibrillation attempts in shockable rhythms 1.
CPR Quality Monitoring: "DEPTH"
DEPTH ensures high-quality compressions that maximize survival 1, 2, 3:
- D = Depth: At least 2 inches (5 cm) for adults 1, 3
- E = ETCO₂: Target PETCO₂ >10 mmHg using quantitative waveform capnography 2, 3
- P = Pauses: Minimize interruptions, keeping pauses under 10 seconds 1, 3
- T = Tempo: Maintain rate of 100-120 compressions/minute 1, 3
- H = Hand position: Allow complete chest recoil between compressions 1, 3
Critical warning: ETCO₂ should NOT be used alone as a mortality predictor or to terminate resuscitation—it's a quality indicator, not a prognostic cutoff 2, 3.
Airway Management: "DOPE"
DOPE troubleshoots problems after advanced airway placement 1:
- D = Displacement: Confirm tube position with waveform capnography 1, 3
- O = Obstruction: Check for secretions, blood, or equipment malfunction 1
- P = Pneumothorax: Assess for tension pneumothorax causing deterioration 1
- E = Equipment failure: Verify oxygen source, bag-mask device, and connections 1
Essential practice point: Waveform capnography is mandatory for confirming and continuously monitoring advanced airway placement—clinical assessment alone is insufficient 1, 3.
Team Roles: "CART"
CART organizes team member assignments 2:
- C = Compressor: Rotates every 2 minutes to maintain quality 2
- A = Airway manager: Secures and maintains the airway 2
- R = Recorder: Documents times, interventions, and rhythms 2
- T = Team leader: Coordinates efforts and makes decisions 2
Practical tip: Plan compressor rotation before fatigue sets in—quality deteriorates rapidly after 2 minutes of continuous compressions 2.
Post-ROSC Care: "ROSC"
ROSC guides immediate post-resuscitation management 1, 3:
- R = Rhythm: Identify and treat dysrhythmias 1, 3
- O = Oxygenation: Avoid both hypoxia and hyperoxia 1, 3
- S = Stabilization: Maintain hemodynamic stability 3
- C = Catheterization: Consider emergent coronary angiography for ST-elevation or ongoing ischemia 3
Additional consideration: Implement targeted temperature management and prevent fever after cardiac arrest 1.
Special Circumstances: "BEAU-TOPS"
BEAU-TOPS addresses unique cardiac arrest scenarios 1:
- B = Bleeding/trauma: Massive hemorrhage requiring damage control 4
- E = Electrolyte abnormalities: Severe hypo/hyperkalemia 1
- A = Anaphylaxis: Epinephrine and airway management 1
- U = Uterine displacement: Lateral tilt for pregnant patients >20 weeks 1, 2, 3
- T = Toxins/overdose: Specific antidotes (e.g., naloxone for opioids) 1
- O = Oxygenation failure: Severe hypoxia as primary cause 1, 4
- P = Pulmonary embolism: Consider thrombolytics 1
- S = Submersion/drowning: Prolonged resuscitation warranted 6
Pregnancy-specific warning: For pregnant patients, perform lateral uterine displacement to relieve aortocaval compression throughout resuscitation 1, 2, 3.