American Association of Critical-Care Nurses (AACN) Certification Practice Test

What are components of the lethal triad of trauma?

1. Hypothermia, acidosis, coagulopathy

2. Hypotension, tachycardia, tachypnea

3. Diarrhea, dementia, and dermatitis

4. CNS depression, respiratory depression, miosis

The correct answer is: Hypothermia, acidosis, coagulopathy

The lethal triad of trauma consists of hypothermia, acidosis, and coagulopathy, which are critical factors that can significantly worsen a patient's condition following severe injury. Hypothermia occurs when the body loses heat faster than it can produce it, leading to a drop in core temperature. This can impair the body’s ability to clot blood and negatively impact various metabolic processes, which can be catastrophic in trauma patients. Acidosis is characterized by an increase in acidity (lower pH) in the blood and body tissues. This can arise from inadequate tissue perfusion and oxygenation, as well as the accumulation of lactic acid due to anaerobic metabolism, which commonly occurs in trauma situations. Acidosis can also further exacerbate coagulopathy, leading to difficulties in blood clotting and increasing the risk of hemorrhage. Coagulopathy refers to a dysfunction in the blood's ability to clot, which is especially prevalent in trauma cases due to blood loss, dilution, and the effects of acidosis. Without effective clotting, small and large blood vessel injuries can lead to uncontrollable bleeding, increasing mortality risk. Together, these components represent a vicious cycle that can rapidly escalate the severity of a patient's condition after trauma, making timely identification and intervention