A 70-year-old man with history of coronary artery disease has a witnessed cardiac arrest. He undergoes 10 minutes of resuscitation with return of spontaneous circulation (ROSC) but remains comatose.
Which of the following treatments for postresuscitation care is most likely to improve outcome for this patient?
A. 100% FiO2 for at least 24 hoursCorrect Answer: C
The tenets of postcardiac arrest care include targeted temperature management (TTM), hemodynamic and ventilation optimization, immediate coronary reperfusion with percutaneous coronary intervention (PCI, if amenable), glycemic control, and neurologic care. The 2015 ACLS guidelines recommend that all comatose (ie, lacking meaningful response to verbal commands) adult patients with ROSC after cardiac arrest should undergo TTM, with a target temperature between 32°C and 36°C maintained constantly for at least 24 hours. This recommendation is based on studies of TTM which compared cooling to temperatures between 32°C and 34°C with no well-defined TTM and found improvement in neurologic outcome for those in whom hypothermia was induced. A more recent high-quality study compared temperature management at 36°C and at 33°C and found outcomes to be similar for both. Taken together, the initial studies suggest that TTM is beneficial, so the recommendation remains to select a single target temperature within the 32°C and 36°C range.
There are multiple goals when it comes to hemodynamic and ventilation optimization in postcardiac arrest patients. Based on the 2015 ACLS guidelines, patients should receive the lowest possible FiO2 to maintain an SpO2 of 94% or greater. The patients’ associated comorbidities and current medical problems will ultimately dictate the goal PaCO2 in the postcardiac arrest patient. Permissive hypercapnia may be most appropriate in patients with acute lung injury while maintenance of normocarbia is warranted in patients with cerebral edema. With regards to hemodynamics goals, the ACLS guidelines recommend maintaining a mean arterial pressure of 65 mm Hg or greater. In patients who have suspected coronary artery occlusion as the source of the cardiac arrest, coronary reperfusion is warranted after return of spontaneous circulation.
The 2015 AHA Guidelines do not recommend a specific target range for glucose management in the postcardiac arrest patient. Variability in glucose levels in this patient population is common and often timedependent. Stress-induced hyperglycemia is commonly found in the earlier phase of a postcardiac arrest patient while hypoglycemia is commonly seen during the rewarming process after 24 hours of hypothermia. Despite numerous studies looking at glycemic control in postcardiac arrest patients, the optimal target range still remains unknown. Given the variability of blood glucose levels in these patients, frequent monitoring should be performed to avoid hypoglycemia and hyperglycemia.
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