Hypovolemia - A Medical Emergency

What Is Volume Depletion?

The human body requires fluids and electrolytes in large amounts to remain healthy and carry out important procedures. Water and electrolytes are the most important fluids required by the body. The brain, kidneys, and adrenal glands are the three most important organs that regulate the body's fluid levels. The body uses these fluids to make chemical substances that help the cells to carry out their functions. However, some of these chemicals and fluids are not required by the body and are in excess. The kidneys' job is to take up these excess fluids from the blood, convert them into the urine, and excrete them. This is how the fluid levels in the body are regulated. The problem arises when the fluid output exceeds the fluid input, meaning a large amount of fluids is lost from the body. The body is made up of thousands of cells. The fluids are present inside (intracellular fluids) and outside the cells (extracellular fluids). Volume depletion occurs when the extracellular fluids are lost in a large amount from the body. There are several causes of volume depletion, including vomiting, diarrhea, sweating, kidney failure, and excessive use of diuretics.

What Are the Causes of Volume Depletion?

Volume depletion, otherwise known as hypovolemia, occurs when the body loses a large amount of sodium. The causes of volume depletion are described below:

1. Bleeding - Bleeding or the loss of blood from the body is one of the causes of volume depletion. Bleeding might occur externally or from internal organs, mainly the gastrointestinal tract. The causes of external bleeding include injuries inflicted by a sharp object, accidents, car crashes, and gunshot injuries. A large amount of blood is lost from the body due to these injuries resulting in volume depletion or hypovolemia.

2. Diarrhea - Diarrhea is a condition in which the person passes loose and watery stools frequently. There are several causes of diarrhea, including food poisoning, bacterial infection, medicinal reactions, viral infections, and food allergies. A large amount of water and essential electrolytes are lost in diarrhea. If diarrhea is accompanied by vomiting, the risk of hypovolemia or volume depletion increases to a large extent.

3. Diuresis - Diuretics include those drugs that work against hypertension or high blood pressure. They act at different sites on the kidneys and do not allow them to reabsorb sodium. Patients on diuretics for a prolonged period are at a high risk of facing volume depletion. It is because these drugs stimulate the kidneys to form urine and increase the passage of body fluids.

4. Burns - Burn injuries are one of the common causes of volume depletion. If 20 percent or more of the body surface area has been damaged due to burns, the fluids start moving out of the body. The skin acts as a barrier to injuries and infections. It prevents the leakage of fluids and keeps them in the body. However, the skin gets damaged when the burn injury is severe. As a result, the fluids start leaking out of the capillaries present in the body resulting in volume depletion or hypovolemia.

5. Sweating - During summer, the outdoor temperatures are usually hot. If the person stays outside for a prolonged time, he starts losing large amounts of fluids due to sweating. People involved in sports activities sweat a lot and tend to lose fluids.

6. Dehydration - Dehydration is often confused with hypovolemia, but the two terms are entirely different. Dehydration or not taking enough fluids is one of the causes of hypovolemia.

7. Inadequate Fluid Intake - If the person suffers from problems like sore throat, mouth ulcers, nasal congestion, and respiratory difficulties, he tends to consume fewer fluids. As a result, the body does not get the required fluids, and the patient suffers from volume depletion or hypovolemia.

8. Increased Metabolic Rate - Fever and infections tend to increase the body's metabolic rates. When the body fluids are metabolized or excreted in excess, the fluid balance gets disturbed, resulting in volume depletion. It is because a large amount of sodium is lost from the body during infections.

9. Malnutrition - Malnutrition is a condition wherein the body does not get enough nutrients, minerals, and vitamins. As a result, the vital body organs fail to work, and the fluid and electrolyte levels of the body are disturbed.

What Are Some of the Signs and Symptoms of Volume Depletion?

Volume depletion or the loss of extracellular fluids from the body creates a problematic situation for the patients. The signs and symptoms of volume depletion are listed below:

• Excessive thirst.

• Weakness.

• Tachycardia or increased heart rate.

• Weight loss if the volume depletion is severe.

• The urine output is less.

• Concentrated urine.

• Dryness of the mouth and mucous membrane.

• If the skin is pinched, it does not return back to its normal position immediately (skin turgor).

• Hypotension or decrease in blood pressure.

• Weak pulse.

How to Assess Volume Depletion?

Volume depletion can be suspected in patients suffering from dehydration, renal disorders, and undergoing diuretic therapy. The following tests need to be done to assess volume depletion:

1. Medical History - The medical history provides an idea about the patient's general health, the condition he is suffering from, the symptoms, and the drug history. For example, patients suffering from renal or cardiac diseases and taking diuretics can be suspected to have disturbances in their fluid volume.

2. Monitor the Vitals - The vitals include blood pressure, respiratory rate, pulse, and heart rate. They must be continuously monitored because the patient usually reports low blood pressure, weak pulse, and low heart rate in hypovolemia or volume depletion. A fall in blood pressure is also noted when the patient changes his position, like standing up suddenly after lying down (orthostatic hypotension).

3. Mental Status - The physical and mental status of the patient must be checked. Usually, the patient is distressed, confused, and agitation and shows a delayed response. Insufficient supply of oxygen to the body tissues, electrolyte disturbances, and low or high blood glucose levels are responsible for the patient's altered mental state.

4. Temperature Check - Check the patient's temperature because fever causes volume deficit by increased sweating and respiratory rate.

5. Urinalysis - In this test, the patient must collect the urine in a container. The urine sample is sent to the laboratory for examination under a microscope. The urine color and urine output must be checked. It is because the patients show decreased urine output in hypovolemia or volume deficit.

6. Blood Test - The doctor recommends the patient undergo a blood test to check the levels of electrolytes, mainly sodium. It is because sodium is lost in large amounts from the body in hypovolemic conditions.

7. Skin Turgor Test - In this test, the doctor holds the skin between the fingers for a few seconds and then releases it. If the skin returns back to its original position immediately, the person is normal. However, if the skin takes time to get back to its original position, the patient is said to be hypovolemic.

How to Manage Volume Deficit or Hypovolemia?

Volume deficit or hypovolemia must be managed soon because the patient suffers from serious complications. The following steps must be followed to manage the volume deficit:

• The patient must drink plenty of water daily. About eight to ten glasses of water a day help restore the body's fluid levels. If the patient is old, set reminders for him to drink water. Oral rehydration solution (ORS) is of great help in patients suffering from volume deficit due to diarrhea.

• If the patient cannot feed himself, the family members must assist and ensure he takes all his prescribed medications on time.

• If the patient can tolerate oral fluids, ask him what fluids he prefers and give him the same.

• Keep the fluids at the bedside for patients with walking difficulties.

• Volume depletion can cause dryness of the mouth and ulcers, so the patient needs to maintain oral hygiene to keep the mouth healthy.

• Plan the daily activities as planning helps save the patient's energy.

• If the patient cannot take the fluids orally, the doctor might inject them into the body through the veins.

• A blood transfusion might be required if severe blood loss has occurred due to injury.

• Patients suffering from diarrhea tend to lose a lot of electrolytes from the body, so these patients need to be prescribed the required medications.

• Eat something light and rich in nutrients to maintain the body's fluid levels.

Conclusion

Volume depletion occurs when the body loses large amounts of fluids and electrolytes, mainly water and sodium. The water present outside the cells, known as extracellular fluids, start moving out of the body due to diarrhea, renal diseases, dehydration, and cardiac diseases. The patient presents with symptoms of weakness, excessive thirst, irregular heart rate, weak pulse, and reduced urine output. The patient's mental status is also altered, making it difficult for him to focus on his work. The patient's blood pressure, temperature, heart rate, and urine output must be checked to diagnose volume depletion. Consult the doctor to know more about the ways and means to maintain the body's fluid levels.