Advanced Cardiovascular Life Support (ACLS) Practice Exam

What is an immediate danger of excessive ventilation during the post-cardiac arrest period for patients who achieve ROSC?

1. Decreased cerebral blood flow

2. Increased heart rate

3. Pneumothorax development

4. Hypoxia

The correct answer is: Decreased cerebral blood flow

Excessive ventilation during the post-cardiac arrest period can lead to decreased cerebral blood flow, which is a critical concern. When a patient achieves return of spontaneous circulation (ROSC), it is essential to ensure adequate cerebral perfusion. Overventilation can cause elevated intrathoracic pressure, which impairs venous return to the heart and subsequently reduces cardiac output. As a result, the decrease in systemic blood pressure can lead to reduced cerebral perfusion pressure, significantly affecting brain oxygenation and function. Maintaining proper ventilation is particularly important for patients who have undergone a cardiac arrest because their cerebral tissue is extremely sensitive to hypoxia and ischemia. If excessive ventilation results in hyperventilation, it can lead to respiratory alkalosis, which further constricts blood vessels in the brain, exacerbating the issue of decreased cerebral blood flow and potentially leading to neurological deficits or complications. Understanding this relationship is vital for clinicians during the post-cardiac arrest care phase to optimize outcomes for patients and minimize the risk of secondary brain injury.