When a patient or family agrees to "full code" or "do everything," they consent to a defined sequence of interventions. The components are described below.
In cardiac arrest, the heart stops pumping blood. Brain cells begin to die within about 4 minutes without oxygen.
If the team decides to attempt resuscitation, the response begins immediately.
The first intervention is chest compressions: pressing on the breastbone at a depth of about 2 inches, at a rate of 100 to 120 per minute. The goal is to manually circulate blood while the heart is not beating.
Approximately 100 pounds of force is required to compress an adult chest to this depth.
In autopsy studies of patients who received CPR, 77 to 85% had rib fractures and 59 to 79% had sternal fractures. Fracture rates are higher in female patients.
AHA guidelines describe these fractures as expected with adequate compression depth.
Within the first few minutes, a breathing tube is placed through the mouth into the windpipe (trachea). A mechanical ventilator takes over breathing.
Among out-of-hospital cardiac arrest patients who reach the hospital alive, approximately 79% require continued mechanical ventilation.
If the rhythm is "shockable" (ventricular fibrillation or pulseless ventricular tachycardia), an electric shock is delivered through pads on the chest.
Approximately 20% of in-hospital cardiac arrests present with a shockable rhythm. The remaining 80% (asystole, pulseless electrical activity) do not benefit from defibrillation.
Epinephrine (adrenaline) is administered intravenously every 3 to 5 minutes. Additional medications — amiodarone, lidocaine, calcium, sodium bicarbonate — may be added based on the rhythm and suspected cause of arrest.
Cumulative epinephrine dose has been independently associated with acute kidney injury in survivors.
Resuscitation typically continues for 20 to 45 minutes, until either the heart restarts or the team decides to stop.
With each additional 5 minutes of CPR without return of spontaneous circulation, the probability of survival with intact neurological function decreases.
Outcomes vary by patient population, time to intervention, initial rhythm, and the duration of effort required to achieve return of spontaneous circulation.