This study investigates the relationship between optic nerve sheath diameter and increased intracranial pressure and its effect on neurologic outcome in post-cardiopulmonary arrest patients.

This study involves patients who have experienced either an in-hospital or out-of-hospital cardiopulmonary arrest, and who meet the 2015 American Heart Association (AHA) inclusion/exclusion criteria for targeted temperature management [i.e., they are comatose or exhibit no meaningful response to verbal commands with return of spontaneous circulation (ROSC) after cardiac arrest]. After induction of hypothermia protocol after cardiopulmonary arrest (i.e., targeted temperature management), patients will undergo ocular ultrasound at three time points.

Inclusion Criteria:

• Patient ≥ 18 years of age
• Patient has experienced either an in-hospital or out-of-hospital cardiopulmonary arrest
• Patient is comatose or exhibits lack of meaningful response to verbal commands with return of spontaneous circulation (ROSC) after cardiopulmonary arrest
• Patient must meet all inclusion criteria as deemed by physician and the 2015 American Heart Association standards for targeted temperature management (TTM) following cardiopulmonary arrest

Exclusion Criteria:

• Patient < 18 years of age
• Patient does not meet inclusion criteria for targeted temperature management (TTM)
• Unable to obtain consent from Legal Authorized Representative (LAR)
• Patient has a Do Not Resuscitate (DNR) order or a Do Not Intubate (DNI) order at the time of consent
• Patient has uncontrollable bleeding
• Patient is able to follow verbal commands
• Patient has another medical condition creating increased ocular pressure, as deemed by physician

Male and female post-cardiopulmonary arrest patients ≥ 18 years of age