Post-Cardiac Arrest Care Basics

Return of spontaneous circulation (ROSC) restores a pulse, not normal physiology. The period after arrest is a second critical illness because the body is recovering from both ischemia and the injury that occurs when blood flow returns. Post-cardiac arrest syndrome has four interacting parts: 1. Post-arrest brain injury from global cerebral ischemia and reperfusion. 2. Post-arrest myocardial dysfunction, in which a stunned heart may contract poorly even after the coronary circulation is reopened. 3. A systemic ischemia-reperfusion response, which can resemble sepsis through inflammation, endothelial activation, vasodilation, and coagulopathy. 4. The persistent cause of the arrest, such as acute coronary occlusion, pulmonary embolism, hemorrhage, hypoxia, electrolyte disturbance, or another untreated process. These components amplify one another. Poor cardiac output reduces cerebral perfusion; systemic vasodilation worsens hypotension; brain injury may prevent airway protection; and the original cause may trigger another arrest. Caring only for the rhythm or the coronary arteries misses much of the patient's risk. Reperfusion itself can injure vulnerable tissue. The sudden return of oxygenated blood promotes reactive oxygen species, excitotoxicity, ionic shifts, inflammation, and apoptosis. For that reason,...