What is the most common cause of pulseless electrical activity (PEA)?

Hypovolemia is recognized as the most common cause of pulseless electrical activity (PEA) primarily due to its impact on the circulatory system. In situations of significant hypovolemia, the body does not have adequate blood volume to maintain effective circulation, despite the presence of electrical activity in the heart. This often occurs in cases of severe dehydration, significant blood loss from trauma or gastrointestinal bleeding, or internal bleeding, leading to a lack of perfusion.

When the heart is unable to generate sufficient pressure to circulate blood effectively, it can result in PEA, where the heart's electrical activity is present, but there is no corresponding mechanical output, leading to the absence of a palpable pulse. Addressing hypovolemia promptly through fluid resuscitation can often reverse this condition, making it crucial for healthcare providers to recognize and treat it as a leading cause of PEA in critical care scenarios.