The principles and measures of post-cardiopulmonary resuscitation management include maintaining effective circulatory and respiratory function, especially cerebral perfusion, preventing re-cardiac arrest, maintaining water, electrolyte and acid-base balance, preventing and treating cerebral edema, acute renal failure and secondary infection, etc., with emphasis on cerebral resuscitation and starting treatment related to improving long-term survival and neurological recovery. (I) Maintain effective circulation A comprehensive evaluation of the cardiovascular system and related factors should be performed to carefully search for the causes of cardiac arrest, especially whether acute myocardial infarction occurs and electrolyte disturbance exists, and make timely treatment. If the patient is hemodynamically unstable, systemic circulating blood volume status and ventricular function should be assessed. Invasive hemodynamic monitoring with a floating pulmonary artery catheter is often required in critically ill patients. To ensure blood pressure, cardiac index, and systemic perfusion, fluids are administered and vasoactive agents (e.g., norepinephrine), positive inotropes (dobutamine), and myocardial contractility enhancing agents (milrinone) are used. (ii) Maintenance of respiration After recovery of autonomic circulation, patients may have varying degrees of respiratory dysfunction, and some patients may still require mechanical ventilation and oxygen therapy. Positive end-expiratory pressure ventilation (PEEP) may be helpful in patients with pulmonary insufficiency combined with left heart failure, but care should be taken to ensure hemodynamic stability at this time. Oxygen concentration, PEEP values, and ventilation per minute can be adjusted clinically based on arterial blood gas results and/or noninvasive monitoring. Persistent hypocapnia (low PCO↓2) can exacerbate cerebral ischemia, so the routine use of hyperventilation should be avoided. (C) Prevention and control of cerebral hypoxia and cerebral edema, also known as cerebral resuscitation. Cerebral resuscitation is the key to the final success of cardiopulmonary resuscitation. In the hypoxic state, the autoregulation of cerebral blood flow is lost, and the maintenance of cerebral blood flow mainly depends on cerebral perfusion pressure. Any factor that causes an increase in intracranial pressure or a decrease in the mean arterial pressure of the body circulation can reduce cerebral perfusion pressure, thus further reducing cerebral blood flow. Normal or slightly increased mean arterial pressure should be maintained in comatose patients to reduce the increased intracranial pressure to ensure good cerebral perfusion. The main measures include: ①Cooling: the high metabolic state after resuscitation or the increased body temperature caused by other reasons can lead to a significant imbalance in the oxygen supply and demand of brain tissue, which can aggravate brain injury. Therefore, after resuscitation from cardiac arrest, body temperature changes should be closely observed and cooling and antipyretic measures should be actively taken. Body temperature of 33-34℃ is appropriate. ② Dehydration: Apply osmotic diuretics with hypothermia treatment to reduce brain tissue edema and lower cranial pressure to help brain function recovery. Usually 20% mannitol (1~2g), 25% sorbitol (1~2g) or 30% urea (0.5~1g) is used for rapid intravenous infusion (2~4 times/day). The combination of furosemide (20-40 mg for the first time, increasing to 100-200 mg IV if necessary), 25% albumin (20-40 ml IV) or dexamethasone (5-10 mg IV every 6-12 hours) can help to avoid or reduce the “rebound phenomenon” caused by osmotic diuresis. When treating dehydration, care should be taken to prevent excessive dehydration, which may result in insufficient blood volume and make it difficult to maintain blood pressure stability. (3) Prevention and control of convulsions: The twitching of the limbs caused by hypoxic brain damage and the chilling reaction to the cooling process should be controlled by applying hibernating drugs. However, prophylactic application of anticonvulsant drugs is not required. Dihydroergotoxine 0.6mg and promethazine 50mg diluted in 5% glucose 100ml can be used for intravenous infusion; diazepam 10mg can also be applied intravenously. Hyperbaric oxygen therapy: through increasing the blood oxygen content and diffusion, increase the partial pressure of oxygen in brain tissue, improve cerebral hypoxia and reduce intracranial pressure. It should be applied early if available. ⑤ Promote early cerebral perfusion: anticoagulation to unblock microcirculation and release cerebrovascular spasm with calcium antagonists. (iv) Prevention and control of acute renal failure If cardiac arrest is prolonged or persistent hypotension after resuscitation, acute renal failure is likely to occur. It is particularly common in elderly patients with pre-existing renal pathology. Renal failure that occurs early in cardiopulmonary resuscitation is mostly due to acute renal ischemia, and its recovery time is longer than that of nephrotoxic patients. Since high doses of dehydrating agents and diuretics are usually administered, the clinical picture may be one of normal or even increased urine output but elevated creatinine (non-oliguric acute renal failure). In the prevention and treatment of acute renal failure, attention should be paid to maintaining effective cardiac and circulatory functions and avoiding drugs that are damaging to the kidneys. If there is still no urine or oliguria after furosemide injection, it indicates acute renal failure. At this time, it should be treated as acute renal failure. (E) Other timely detection and correction of water-electrolyte disorders and acid-base imbalance, and prevention and control of secondary infection. For patients with loss of bowel sounds and mechanical ventilation with impaired consciousness, a gastric tube should be left in place and gastrointestinal nutrition should be applied as early as possible.