Hemorrhagic shock: Causes and emergency care

The American College of Surgeons Advanced Trauma Life Support divides hemorrhagic shock into four categories. The organization bases each stage on how much blood loss an otherwise healthy person weighing 70 kilograms (kg) sustains. As a point of reference, a person who weighs 70 kg typically has about 5 liters (L) of blood in their body.

The four hemorrhagic shock stages are as follows:

Stage 1

An individual has lost up to 15% — about 750 milliliters (mL) — of their total blood volume. Their blood pressure, respiratory rate, and pulse pressure do not change. Their heart rate is typical or slightly elevated.

Stage 2

A person has lost 15–30% of their blood (around 750–1,500 mL). Heart and respiratory rates increase. The heart rate is likely to be between 100–120 beats per minute (BPM). Blood pressure remains unchanged, or it may slightly decrease.

Stage 3

An individual has lost 30–40% of their blood (around 1,500–2,000 mL). A significant drop in blood pressure occurs. The heart rate is more than 120 BPM, and there is a significant rise in respiratory rate. Confusion and other mental symptoms may occur.

Stage 4

A person has lost more than 40% of their blood (over 2,000 mL). Another significant drop in blood and pulse pressure occurs. The mental status of the person becomes increasingly altered, and the heart rate stays over 120 BPM.

Symptoms of hemorrhagic shock may include:

If internal bleeding occurs, a person may experience symptoms such as:

If anyone experiences any of the symptoms mentioned above, they should seek immediate medical attention.

If a person is bleeding heavily or has shock symptoms, it is important to contact the emergency services immediately. While waiting for emergency services, people can perform the following steps to help reduce bleeding:

1. If the person who is bleeding does not have a head, neck, or spine injury, they can lie on their back and raise their legs about 12 inches (in) from the ground. Do not elevate their head.
2. Clean the wound, removing dirt or debris. Do not remove any stick, knife, embedded glass, or other objects stuck in the injury site.
3. If the wound is clear of debris and contains no visible stuck objects, tie the area with any available fabric to reduce blood loss. Apply pressure to the wound and, if possible, tape it to keep the fabric in position.
4. Wait for the emergency services to arrive.

The main cause of hemorrhagic shock is losing a significant amount of blood, called hemorrhage. Blood carries oxygen to the organs and tissues. When a person sustains heavy blood loss, the body shuts down as there is insufficient blood to bring oxygen to the organs.

Some causes of hemorrhage may include:

• trauma
• deep cuts
• amputation
• severe burns
• gunshot wounds
• penetrative injuries

A physical examination can help identify the signs of shock. As part of the initial assessment, a doctor will likely perform a focused assessment with sonography for trauma (FAST) exam. This involves using ultrasound techniques to look for free blood in four areas, consisting of the:

• heart
• right upper quadrant around the liver
• left upper quadrant around the spleen
• suprapubic area around the bladder

A doctor will likely also perform an extended FAST exam, which involves conducting the usual FAST exam plus an ultrasound of both lungs.

Other tests that can be helpful include:

• imaging tests, such as CT scans or X-rays
• blood tests to determine a person’s blood type in cases where transfusion becomes necessary
• taking a medical history to determine whether a person has any underlying health conditions that could be contributing to the blood loss

The treatment for hemorrhagic shock typically includes intravenous fluids and blood transfusions, depending on the amount of blood lost. People who have experienced significant blood loss may require resuscitation.

Hemorrhagic shock could also need a massive transfusion protocol, which involves transfusing 10 units of packed red blood cells with a set ratio of platelet and plasma transfusions within 24 hours.

After doctors stabilize the person with hemorrhagic shock, they treat the cause of the bleeding. Doctors may also give medications that help increase blood pressure, for example, vasopressors.

Hemorrhagic shock is the leading cause of death for Americans between 1–46 years old. It accounts for about 35% of prehospital deaths and 40% of deaths within the first 24 hours after injury.

A major complication that can occur with hemorrhagic shock is organ failure and tissue death.

There are some major differences between both conditions.

Hypovolemic shock is a sudden drop in blood volume. While it can have hemorrhagic and nonhemorrhagic causes, it is less likely to occur after heavy bleeding.

Significant fluid loss tends to be the cause of hypovolemic shock. Factors such as diarrhea and vomiting can also cause this type of shock. In comparison, bleeding is the only cause of hemorrhagic shock.

Learn more about hypovolemic shock.

Hemorrhagic shock is a life threatening condition that requires immediate medical intervention. The condition occurs when a person has sustained significant blood loss and the amount of blood remaining inside the body is not sufficient to provide enough oxygen to organs and tissues.

The most common causes of hemorrhagic shock are deep cuts, gunshot wounds, trauma, and penetrative injuries.

If someone has signs of shock, it is important to call the emergency services immediately. Left untreated, the outlook for hemorrhagic shock is not favorable.