Hypovolemic Shock

What Is Hypovolemic Shock?

Hypovolemic shock, also known as hemorrhagic shock, is a life-threatening condition that results when you lose more than 20 percent (one-fifth) of your body’s blood or fluid supply.
This severe fluid loss makes it impossible for the heart to pump a sufficient amount of blood to your body. Hypovolemic shock can lead to organ failure. This condition requires immediate emergency medical attention.
Hypovolemic shock is the most common type of shock, with very young children and older adults being the most susceptible.

Causes

What causes hypovolemic shock?

Hypovolemic shock results from significant and sudden blood or fluid losses within your body. Blood loss of this magnitude can occur because of:

• bleeding from serious cuts or wounds
• bleeding from blunt traumatic injuries due to accidents
• internal bleeding from abdominal organs or ruptured ectopic pregnancy 
• bleeding from the digestive tract
• significant vaginal bleeding

In addition to actual blood loss, the loss of body fluids can cause a decrease in blood volume. This can occur in cases of:

• excessive or prolonged diarrhea
• severe burns
• protracted and excessive vomiting
• excessive sweating

Blood carries oxygen and other essential substances to your organs and tissues. When heavy bleeding occurs, there is not enough blood in circulation for the heart to be an effective pump. Once your body loses these substances faster than it can replace them, organs in your body begin to shut down and the symptoms of shock occur. Blood pressure plummets, which can be life-threatening.

Symptoms

What are the symptoms of hypovolemic shock?

The symptoms of hypovolemic shock vary with the severity of the fluid or blood loss. However, all symptoms of shock are life-threatening and need emergency medical treatment. Internal bleeding symptoms may be hard to recognize until the symptoms of shock appear, but external bleeding will be visible. Symptoms of hemorrhagic shock may not appear immediately. Older adults may not experience these symptoms until the shock progresses significantly.
Some symptoms are more urgent than others.

Mild symptoms

Mild symptoms can include:

• headache
• fatigue
• nausea
• profuse sweating
• dizziness

Severe symptoms

Severe symptoms, which must be taken seriously and warrant emergency medical attention, include:

• cold or clammy skin
• pale skin
• rapid, shallow breathing
• rapid heart rate
• little or no urine output
• confusion
• weakness
• weak pulse
• blue lips and fingernails
• lightheadedness
• loss of consciousness

The sign of external hemorrhaging is visible, profuse bleeding from a body site or area of injury.
Signs and symptoms of internal hemorrhaging include:

• abdominal pain
• blood in the stool
• black, tarry stool (melena)
• blood in the urine
• vomiting blood
• chest pain
• abdominal swelling

While some symptoms like abdominal pain and sweating can point to something less urgent like a stomach virus, you should seek immediate medical attention when seeing groupings of these symptoms together. This is especially true for the more serious symptoms. The longer you wait, the more damage can be done to your tissues and organs.
If you have any signs of hemorrhaging or of hemorrhagic shock, seek medical attention immediately.

Emergency care and first aid

Untreated hypovolemic shock will lead to death. Hypovolemic shock is a medical emergency. Call 911 immediately if you observe a person experiencing shock symptoms. Until responders arrive:

• Have the person lie flat with their feet elevated about 12 inches.
• Refrain from moving the person if you suspect a head, neck, or back injury.
• Keep the person warm to avoid hypothermia.
• Don’t give the person fluids by mouth.

Don’t elevate their head. Remove any visible dirt or debris from the injury site. Do not remove embedded glass, a knife, stick, arrow, or any other object stuck in the wound. If the area is clear of debris and no visible object protrudes from it, tie fabric, such as a shirt, towel, or blanket, around the site of injury to minimize blood loss. Apply pressure to the area. If you can, tie or tape the fabric to the injury.

Complications

What complications are associated with hypovolemic shock?

A lack of blood and fluid in your body can lead to the following complications:

• damage to organs such as your kidney or brain
• gangrene of the arms or legs
• heart attack

The effects of hypovolemic shock depend on the speed at which you’re losing blood or fluids and the amount of blood or fluids you are losing. The extent of your injuries can also determine your chances for survival. Chronic medical conditions such as diabetes, previous stroke, heart, lung, or kidney disease, or taking blood thinners like Coumadin or aspirin can increase the likelihood that you’ll experience more complications from hypovolemic shock.

Diagnosis

How is hypovolemic shock diagnosed?

There are often no advance warnings of shock. Instead, symptoms tend to arise only when you’re already experiencing the condition. A physical examination can reveal signs of shock, such as low blood pressure and rapid heartbeat. A person experiencing shock may also be less responsive when asked questions by the emergency room doctor.
Heavy bleeding is immediately recognizable, but internal bleeding sometimes isn’t found until you show signs of hemorrhagic shock.
In addition to physical symptoms, your doctor may use a variety of testing methods to confirm that you’re experiencing hypovolemic shock. These include:

• blood testing to check for electrolyte imbalances, kidney, and liver function
• CT scan or ultrasound to visualize body organs
• echocardiogram, an ultrasound of the heart
• electrocardiogram to assess heart rhythm
• endoscopy to examine the esophagus and other gastrointestinal organs
• right heart catheterization to check how effectively the heart is pumping
• urinary catheter to measure the amount of urine in the bladder 

Your doctor may order other tests based on your symptoms.

How is hypovolemic shock treated?

Once at a hospital, a person suspected of having hypovolemic shock will receive fluids or blood products via an intravenous line, to replenish the blood lost and improve circulation. Treatment revolves around controlling loss of fluid and blood, replacing what’s been lost, and stabilizing damage that both caused and resulted from the hypovolemic shock. This will also include treating the injury or illness that caused the shock, if possible.
These include:

• blood plasma transfusion
• platelet transfusion
• red blood cell transfusion
• intravenous crystalloids

Doctors may also administer medications that increase the heart’s pumping strength to improve circulation and get blood where it’s needed. These include:

• dopamine
• dobutamine
• epinephrine
• norepinephrine 

Antibiotics may be administered to prevent septic shock and bacterial infections.
Close cardiac monitoring will determine the effectiveness of the treatment you receive.

In older adults

Hypovolemic shock in older adults

Hypovolemic shock is dangerous for everyone, but it can be particularly dangerous in older adults. Older adults who experience hypovolemic shock have higher mortality rates than their younger counterparts. They have less tolerance for the shock, and earlier treatment to prevent other complications is vital. This can be made more complicated, as older adults may not show symptoms of shock until later than younger populations.

Outlook

Long-term outlook

Common complications of hemorrhagic shock include:

• kidney damage
• other organ damage
• death

Some people may also develop gangrene due to decreased circulation to the limbs. This infection may lead to amputation of the affected limbs.
Recovery from hypovolemic shock depends on factors like the patient’s prior medical condition and the degree of the shock itself.
Those with milder degrees of shock will have an easier time recovering. If severe organ damage results from the shock, it can take much longer to recover, with continued medical interventions needed. In severe cases, organ damage may be irreversible.
Overall, your outlook will depend on the amount of blood you lost and the type of injury you sustained. The outlook is best in healthy patients who haven’t had severe blood loss.

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