Progressive Care Nursing Certification (PCCN) Practice Exam

What occurs to the heart rate as intracranial pressure increases?

1. It increases

2. It decreases

3. It remains unchanged

4. It fluctuates

The correct answer is: It decreases

As intracranial pressure (ICP) increases, the heart rate tends to decrease. This phenomenon is related to a physiological response known as the Cushing reflex, which occurs when the body experiences increased ICP. The Cushing reflex is characterized by a triad of symptoms: hypertension, bradycardia (decreased heart rate), and irregular respirations. When ICP rises, it leads to a decrease in cerebral perfusion pressure, meaning that the brain is not receiving adequate blood flow. The body responds by activating the baroreceptors in the cardiovascular system, which detect the increased blood pressure caused by compensatory mechanisms to maintain cerebral perfusion. In response to this situation, the heart rate slows down as part of a protective mechanism to preserve blood flow to vital organs, including the brain. Understanding this relationship is crucial for recognizing signs of increased ICP and implementing appropriate interventions. Monitoring heart rate, alongside other vital signs, can provide insight into the patient’s neurological status and potential complications that may arise from elevated ICP.