Bleeding in an adult is considered life-threatening if the amount of blood lost equals at least 40% of the total blood volume, which is about 2 liters in an average adult. This level of blood loss is classified as a Class IV hemorrhage and is usually fatal without immediate medical intervention.
Blood Loss Classification and Life-Threatening Threshold
- An average adult has about 5 liters of blood.
- Losing more than 40% (~2 liters) is life-threatening and requires urgent treatment.
- Severe symptoms at this stage include extreme confusion, collapse, and no urine output.
- Immediate medical intervention like blood transfusion and surgical control is vital.
Summary
Life-threatening bleeding equals blood loss of 40% or more of total blood volume in adults, which translates to approximately 2 liters of blood. This condition is a medical emergency with a high risk of death without prompt care.