Inclusion Criteria:

• * Adult (≥18 years old) patients
• * Patients with a cardiac arrest (a lack of palpable pulse or perfusing cardiac activity) while admitted to the hospital
• * Patients admitted to a ward (telemetry or non-telemetry) or an intensive care unit, or are admitted but still in the emergency department waiting for a hospital bed
• * Patients who achieved return of spontaneous circulation (ROSC defined as \>20 minutes of sustained spontaneous circulation) OR initiated on extracorporeal membrane oxygenation (eCPR) with chest compressions ongoing
• * Patients survived for 6 hours after ROSC

Exclusion Criteria:

• * Cardiac arrest in non-inpatients (e.g. outpatients, visitors)
• * Patients whose cardiopulmonary resuscitation (CPR) starts outside of the hospital
• * Non-index arrests (arrests that are not the patient's first arrest during the hospital admission; this also excludes patients who were initially admitted for an out-of-hospital cardiac arrest)
• * Patients suffering IHCA in the operating room (OR) or post anesthesia care unit (PACU)
• * Patients with cardiac arrest after arriving to an emergency department (ED) but prior to being evaluated and admitted to the hospital
• * Cardiac arrests lasting \<2 minutes (i.e. chest compressions performed \<2 minutes)
• * Cardiac arrests where the patient is transitioned to comfort focused care within 6 hours of return of spontaneous circulation (ROSC)