Cardiac Emergencies (ACLS) Flashcards

In ACLS, 'no-flow time' refers to:

Answer: The interval between cardiac arrest and initiation of CPR (time without any perfusion)

No-flow time is the critical period between cardiac arrest and first CPR compression during which no cardiac output occurs; minimising this time is the single most important factor in improving OHCA survival.

Lidocaine 1-1.5mg/kg IV is an alternative to amiodarone for shock-refractory VF/pVT when:

Answer: Amiodarone is unavailable

Lidocaine is recommended as an alternative antiarrhythmic when amiodarone is unavailable for shock-refractory VF/pVT; while amiodarone has superior evidence, lidocaine remains an acceptable alternative.

The ACLS guideline recommendation for CPR compression rate is:

Answer: 100-120 compressions per minute

Compression rates of 100-120/min optimise cardiac output during CPR; rates above 120/min reduce compression depth and below 100/min reduce perfusion — both extremes worsen outcomes.

Which ECG finding during cardiac arrest indicates a shockable rhythm?

Answer: Ventricular fibrillation (VF) or pulseless ventricular tachycardia (pVT)

Only VF and pVT are shockable rhythms in cardiac arrest; asystole and PEA are non-shockable and treated with CPR plus epinephrine. Rhythms with pulses are not cardiac arrest rhythms.

Airway management during CPR should prioritise:

Answer: High-quality continuous compressions over airway interventions — don't interrupt compressions for prolonged intubation attempts

Current guidelines de-emphasise early intubation during CPR, as interruptions to compressions for intubation worsen outcomes; BVM ventilation is acceptable, and intubation should be performed without interrupting compressions.

Post-cardiac arrest care includes targeting which oxygen saturation to avoid hyperoxia?

Answer: 94-98% (avoiding both hypoxia and hyperoxia)

Both hypoxia and hyperoxia are harmful post-ROSC; hyperoxia (PaO2 >300 mmHg) is associated with worse neurological outcomes due to increased oxidative stress; titrate oxygen to 94-98% SpO2.