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A common misconception is that the resuscitation ends after restoration of pulses. In fact, the body is in an extremely tenuous state in the immediate post arrest period. Without proper support, cardiac arrest may recur. In essence, the restoration of pulses represents the beginning of post arrest care.

The goals of post arrest care are: 1) maintain hemodynamic stability; 2) preserve the brain; and 3) correct metabolic derangements. The salient elements of post arrest care include:

 Vasopressor titration.

 Ventilator management.

 Targeted temperature management.

 Appropriate cardiac catheterization.

 Sedation.

 Glucose and electrolyte management.

The most important EMS consideration is vasopressor support after ROSC. Animal models of cardiac arrest predictably develop cardiovascular collapse shortly after ROSC [104]. This hemodynamic instability may result from myocardial stunning as well as the waning effect of epinephrine [105–108]. Because of the likely need for vasopressor support, it is reasonable to prepare a dopamine, norepinephrine, or epinephrine infusion immediately after achieving ROSC. Push dose vasopressors have also been used to increase systolic blood pressure in the critical care transport arena, though an increase in mortality was noted [109]. Rescuers need to anticipate cardiovascular collapse. If they wait for collapse to occur, the patient will deteriorate before rescue therapy can be initiated.

Coronary artery disease is common in this population and is independent of the primary arrest rhythm [110]. Early coronary angiography is strongly supported in guideline statements and has been associated with improved outcomes following ROSC [110, 111]. A prehospital 12‐lead ECG analysis is indicated in the patient successfully resuscitated from cardiac arrest, as this is helpful in identifying patients who should receive immediate catheterization [112]. Patients with a history consistent with acute coronary syndrome or obvious ECG changes should be transported to a percutaneous coronary intervention center.

The induction of mild hypothermia for brain preservation has demonstrated significant improvement in neurologic outcome in comatose patients following cardiac arrest [113, 114]. Hypothermia is believed to decrease cerebral metabolism, reduce free radical production, and impose direct protective effects on neural and cardiac tissue [115–119].

In the Hypothermia After Cardiac Arrest (HACA) study, comatose survivors of VF/VT cardiac arrest were randomized to a goal temperature of 32°C to 34°C for 24 hours or normal care and normothermia [113]. The investigators noted 55% of patients receiving hypothermia enjoyed a good outcome (defined as a Cerebral Performance Category 1 [Good Recovery] or 2 [Moderate Disability]) compared with 39% of normothermic patients. In a separate study, patients were randomized to a goal temperature of 33°C for 12 hours or normal care and normothermia [114]. Forty‐nine percent of the hypothermic patients enjoyed a good outcome (defined as discharge home or to acute rehabilitation), compared with 26% of the normothermic patients. However, the specific strategy used might matter. When 950 post cardiac arrest adults were randomized to temperature management at 36°C or 33°C for 24 hours, there was no outcome advantage [115]. However, both groups received precise attention to temperature management and intensive care, which may be greatly influential factors in survival. Current thinking is that, for comatose survivors of out‐of‐hospital cardiac arrest, the goal is to maintain a constant temperature between 32°C and 36°C during temperature management [1].

Early prehospital induction of hypothermia is empirically appealing and supported by animal studies. However, while initiation of prehospital cooling results in lower temperatures at hospital arrival, it does not convey to improved rates of survival with good neurologic outcomes (risk ratio 1.04, 95% CI 0.93‐1015) [116]. Furthermore, it is associated with increased rates of rearrest. To date, intra‐arrest hypothermia has not yielded additional survival benefit [117, 118].

Critical care management also includes careful attention to ventilation, euglycemia, and metabolic parameters. Titrating ventilation to an EtCO₂ of 35‐40 mmHg is reasonable and consistent with present guidelines [1]. However, the post arrest patient is critically ill and frequently requires the care of multiple specialists who may not be available at all hospital facilities [119–122].