Triangle of Death (medicine)

Triangle of Death is a medical term describing the fatal combination of hypothermia, acidosis and coagulopathy.

The three conditions share a complex relationship; each factor can compound the others, resulting in high mortality if the cycle continues uninterrupted.

Severe haemorrhage in trauma diminishes oxygen delivery, causing the patient's body temperature to drop (hypothermia). This in turn can halt the coagulation cascade, preventing blood from clotting (coagulopathy).

In the absence of blood-bound oxygen and nutrients (hypoperfusion), the body's cells burn glucose for energy (lactic acidosis), which in turn increases the blood's acidity (metabolic acidosis). Such an increase in acidity can reduce the efficiency of the heart muscles (myocardial performance), further reducing the oxygen delivery and hence triggering a deadly cycle.