Chapter 2 of 522% of exam

Cardiology & Resuscitation

Cardiac arrest and acute coronary syndromes are time-critical emergencies. This chapter covers high-quality CPR, AED use, and BLS cardiac care.

High-Quality CPR

Effective compressions maintain blood flow to the heart and brain. Rate, depth, recoil, and minimal interruptions all matter.

Rate 100 to 120 per minute

Applies to adults, children, and infants for effective circulation.

Adult depth at least 2 inches

Compress at least 5 cm but not more than 6 cm on the lower half of the sternum.

Allow full chest recoil

Full recoil lets the heart refill, improving the next compression's output.

Minimize interruptions

Blood flow falls quickly when compressions stop, so keep pauses short.

CPR Ratios by Age

Compression-to-ventilation ratios depend on age and number of rescuers. Depth also varies by patient size.

Adult 30:2 one or two rescuers

Adults always use 30 compressions to 2 breaths in BLS.

Child/infant 30:2 single rescuer

A lone rescuer uses 30:2 for children and infants.

Child/infant 15:2 with two rescuers

Two rescuers switch to 15:2 for pediatric patients.

Infant depth about 1.5 inches

Roughly one third of the chest depth using two fingers or two thumbs.

AED Use

Early defibrillation is the strongest predictor of survival in shockable arrest. The AED guides the rescuer through analysis and shocks.

Apply and follow prompts early

Attach the AED as soon as it arrives and follow its voice prompts.

Resume CPR after any outcome

After a shock or 'no shock advised', immediately resume compressions.

Clear medication patches

Remove patches under pad sites and wipe the skin to avoid burns or blocked energy.

Use adult pads on children if needed

If pediatric pads are unavailable, use adult pads placed so they do not touch.

Acute Coronary Syndrome

Chest pain from reduced blood flow to the heart requires prompt recognition and BLS treatment. Associated signs help identify atypical presentations.

Recognize associated signs

Sweating, nausea, and shortness of breath often accompany cardiac chest pain.

Assist with chewable aspirin

Give aspirin for suspected ACS if there is no allergy or contraindication.

Confirm BP before nitroglycerin

Ensure adequate systolic pressure and no recent erectile dysfunction drugs.

Position of comfort

Allow a stable cardiac patient to sit up and keep them calm and at rest.

Team Resuscitation

Coordinated teamwork keeps compressions effective and transitions smooth. Rescuer fatigue is a hidden threat to quality.

Switch compressors every 2 minutes

Rotate during rhythm checks to prevent fatigue-related quality loss.

Check pulse no more than 10 seconds

Feel the carotid briefly; if no definite pulse, start compressions.

Start compressions first

For an unresponsive, pulseless adult, begin compressions immediately.

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Trauma

Last updated: July 2026