What are the most common causes of cardiac arrest in trauma cases?

The most common causes of cardiac arrest in trauma cases primarily relate to physiological changes or complications that arise from the trauma itself. In this context, hypovolemia, hypoxia, and tension pneumothorax are key factors.

Hypovolemia occurs when there is significant blood loss, leading to decreased blood volume and resulting in inadequate perfusion of vital organs, which can trigger cardiac arrest. Hypoxia, or insufficient oxygen supply to the tissues, often accompanies severe trauma, particularly if there are associated injuries to the respiratory system or if the airway is compromised. Tension pneumothorax involves the accumulation of air in the pleural cavity, which puts pressure on the heart and major blood vessels, affecting blood flow and leading to cardiac arrest if not promptly addressed.

These conditions are particularly relevant in trauma situations, making them critical considerations when assessing a patient who has experienced major injuries. In contrast, while options like drug overdose and electrical shock can indeed lead to cardiac arrest, they are not as commonly associated with trauma events as the conditions mentioned in the correct response.