What Is Hypovolemic Shock?
Hypovolemic shock, also called 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 sufficient blood to your body. Hypovolemic shock can cause many of your organs to fail. The condition requires immediate emergency medical attention in order to survive.
What Causes Hypovolemic Shock?
Hypovolemic shock results from significant blood and/or fluid losses in your body. Blood loss of this magnitude can occur because of:
- bleeding from cuts or wounds
- bleeding from blunt traumatic injuries due to accidents or seizure activity
- internal bleeding from the gastrointestinal tract or ruptured ectopic pregnancy
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 diarrhea
- severe burns
- protracted and excessive vomiting
- excessive sweating
When heavy bleeding occurs, there is not enough blood flow to the organs in your body. Blood carries oxygen and other essential substances to your organs and tissues. When these substances are lost more quickly than they can be replaced, organs in the body begin to shut down. As your heart shuts down and fails to circulate an adequate amount of blood through your body, symptoms of shock occur. Blood pressure plummets and there is a massive drop in body temperature, which can be life threatening.
According to the Mayo Clinic, hemorrhagic shock is the leading cause of death in people with traumatic injuries. (Mayo Clinic)
What are the Symptoms of Hypovolemic Shock?
The symptoms of hypovolemic shock vary with the severity of the fluid and/or blood loss. However, all symptoms of shock are life threatening and should be treated as a medical emergency. Internal bleeding symptoms may be hard to recognize until symptoms of shock appear. However, external bleeding will be visible. Symptoms of hemorrhagic shock may not appear immediately. Older adults may not experience these symptoms until the shock has progressed significantly.
- blue lips and fingernails
- low or no urine output
- profuse sweating
- shallow breathing
- chest pain
- loss of consciousness
- low blood pressure
- rapid heart rate
- weak pulse
The sign of external hemorrhaging is bleeding profusely at the site of injury.
Signs of internal hemorrhaging include:
- abdominal pain
- blood in the stool
- blood in the urine
- vaginal bleeding (heavy, usually outside of normal menstruation)
- vomiting blood
- chest pain
- abdominal swelling
If you have any signs of hemorrhaging or of hemorrhagic shock, seek medical attention immediately. Have someone drive you to the hospital or call 911. Do not drive to the hospital on your own if you are bleeding profusely or if you have any symptoms of shock.
Emergency Care and First Aid
Because 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 his or her feet elevated about 12 inches
- refrain from moving the person if a head, neck, or back injury is suspected
- keep the person warm
- refrain from giving the person fluids by mouth because of the risk of choking
Do not 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 is protruding from it, tie fabric around the site of injury such as a shirt, towel, or blanket to minimize blood loss. Apply pressure to the area. If you can, tie or tape the fabric to the injury.
What Complications are Associated with This Condition?
Untreated hypovolemic shock will lead to death. 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 amount and speed at which you are losing blood and/or fluids. The extent of your injuries can also determine your chances for survival. If you have chronic medical conditions such as diabetes or heart, lung, or kidney disease, these conditions can increase the likelihood you will experience more complications from hypovolemic shock.
How Is the Condition Diagnosed?
There are often no advance warnings of shock. Instead, symptoms tend to arise only when you are already in the throes of the condition. A physical examination can reveal signs of shock, such as low blood pressure and rapid heartbeat. The person may also be less responsive when asked questions by the emergency room doctor.
While heavy bleeding is immediately recognizable, internal bleeding sometimes isn’t found until someone shows signs of hemorrhagic shock.
In addition to physical symptoms, your physician may use a variety of testing methods to confirm you are experiencing hypovolemic shock. These include:
- blood testing to check for electrolyte imbalances and kidney function
- CT scan or an ultrasound to visualize body organs
- echocardiogram to measure heart rhythm
- endoscopy to examine the esophagus and other gastrointestinal organs
- right heart catheterization to check how blood is circulating
- urinary catheterization to measure the amount of urine in the bladder
Other tests may be ordered based on your symptoms.
How Is the Condition Treated?
Once at a hospital, a person suspected of having hypovolemic shock will be given fluids and/or blood products via an intravenous line. Medications that increase the heart’s pumping abilities also may be administered. These include dopamine, dobutamine, epinephrine, and/or norepinephrine.
Close cardiac monitoring, as well as monitoring of kidney function, will be done to determine the effectiveness of treatment.
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. Common complications of hemorrhagic shock include:
- kidney damage
- other organ damage
Some people may also develop gangrene due to decreased circulation to the limbs. This infection may result in amputation of the affected limbs.