Hemodynamic Disorders - Causes, Symptoms, and Treatment

Introduction

Hemodynamics studies blood flow through arteries and veins and the forces that affect the blood flow. Homeostatic mechanisms regulate the circulatory system of the body. The pressure inside the blood vessels, the osmolarity, and the blood vessels' integrity regulate the body's normal homeostatic mechanism.

What Is the Relationship Between Fluid Volume and Hemodynamic Disorders?

The human body is made up of two compartments. The intracellular fluid is the water inside the cells and comprises two-thirds of the total body water content. The extracellular fluid is the water outside the cells and comprises one-third of the total water content. One-fourth of the extracellular fluid is inside the blood vessels, called the intravascular fluid. The remaining three-fourths of the fluid is outside the interstitial space's blood vessels. The electrolytes in the body determine the water distribution between the intracellular and extracellular compartments. Within the extracellular compartment, the proteins regulate the fluid movement between the intravascular and the interstitial space. The body fluid continuously flows between all the compartments of the body. Fluids move out of the capillary due to differences in the hydrostatic pressure within the capillary and osmotic pressure of the extracellular fluid. The inward movement of the fluid is due to the extracellular fluid's hydrostatic pressure and the blood vessel's osmotic pressure. The body's lymphatic system removes the excess fluid that does not return to the blood vessels. Any changes within the blood vessels’ volume, pressure, or protein content affect the water movement across the vessel's wall.

What Are the Types of Hemodynamic Disorders?

Hemodynamic disorders cover a wide range of conditions and can be majorly categorized into:

• Circulatory Disorders:

  • Edema.

  • Hyperemia.

  • Shock.

  • Hemorrhage.

• Thromboembolic Disorders:

  • Thrombosis.

  • Embolism.

  • Infarction.

What Is Edema?

An increase in the fluid amount in the interstitial space is called edema. It may be localized in a particular area of the body or may be present systemically.

• Types: Edematous fluid may be transudate or exudate.

  • Transudate - A transudate is an edematous fluid that is high in protein content and has an excessive amount of white blood cells present in them. It is formed as a result of inflammation.

  • Exudate - An exudate is an edematous fluid with low protein content and a few white blood cells. It is formed due to an imbalance of vascular forces within the blood vessels.

• Causes: There are many factors responsible for edema.

  • Gravity - Standing or sitting for too long can cause fluid accumulation in one place in the arms and feet, resulting in edema.

  • Weak Veins - If the valves of the vein are weak, it cannot push the blood efficiently to the heart resulting in varicose veins and edema.

  • Medical Conditions - Underlying conditions like congestive heart failure, thyroid disease, kidney, liver, and lung problems result in edema.

  • Side Effects From Medicines - Side effects from blood pressure medicine and pain relievers (NSAIDs) can result in edema.

  • Pregnancy - Swelling is commonly seen during pregnancy due to the pressure exerted by the uterus on the blood vessels.

• Complications:

  • Swelling in the body parts.

  • Stretching of the skin. Stretched skin can cause itching.

  • Blood flow decreases in affected areas.

  • A feeling of stiffness in the body.

• Treatment - The treatment of edema lies in treating underlying diseases like congestive heart failure and lung, renal, and liver disease. Other than that, lifestyle modifications like avoiding sitting or standing for long periods, wearing compression stockings, and reducing salt intake help the patient.

What Is Hyperemia?

When the blood amount increases in the blood vessels of an organ or tissue like the liver, heart, and skin, it results in hyperemia.

• Types:

  • Active Hyperemia - When the blood supply to an organ increases due to an increase in demand, it is known as active hyperemia. For example, exercising.

  • Passive Hyperemia - If the blood is not properly relieved from an organ, it results in the pooling up of the blood in the blood vessels. This is known as passive hyperemia or congestion.

• Causes:

  • Active Hyperemia -

    • Exercise - The blood supply increases since the oxygen demand increases more upon exercise.

    • Digestion - More blood is needed to break down the food and absorb nutrition from the food supply.

    • Inflammation - Blood flow is more at the injured or infected site.

  • Passive Hyperemia-

    • Heart Failure- Blood starts pooling in the heart if it cannot pump properly, resulting in swelling and congestion of organs like the liver, kidney, and spleen.

    • Deep Vein Thrombosis - Clot is present in the veins of the lower legs and thus does not allow the blood to flow, resulting in blood pooling in the lower limbs.

    • Hepatic Vein Thrombosis - Blockage of the hepatic vein causes blood pooling and congestion in the liver.

• The most common symptoms are redness of the skin and the skin being warm upon touch. The other symptoms depend on the underlying disease. For example, heart failure patients may experience shortness of breath, swelling of the legs and abdomen, frequent cough, and weakness. Patients with hepatic vein thrombosis experience itching, swelling of the legs, pain in the upper right abdomen, etc.

• Treatment - Active hyperemia, like in the case of exercise and digestion, is not treated. Treatment is required only in case of passive hyperemia or congestion. The medical condition is treated as per the diagnosis.

What Is Shock?

Shock results from inadequate blood supply to the organs of the body.

• Types and Causes:

  • Septic Shock - When the bacteria enter the bloodstream, it releases toxins in the blood resulting in blood poisoning or sepsis and septic shock.

  • Hypovolemic Shock - It occurs when there is severe loss of blood and fluid, as seen in cases of injuries, bleeding, dehydration, etc.

  • Obstructive Shock - When the blood supply is interrupted, and the blood does not reach its target organ and tissue adequately, it can result in obstructive shock. A few of these conditions include pneumothorax (collapsing of the lungs), and hemothorax (collection of blood between walls of the chest and lungs)

  • Cardiogenic Shock - It occurs due to damage to the heart muscles, such that the heart does not pump blood adequately, thus decreasing the blood supply. It is seen in conditions like arrhythmia and myocardial infarction.

  • Anaphylactic Shock - It results from a complication due to a severe allergic reaction or anaphylaxis.

  • Spinal or Neurogenic Shock - It occurs due to injury to the central nervous system, particularly the spinal cord.

• Symptoms:

  • Low blood pressure.

  • Severe dehydration.

  • Increased heart rate and pulse.

• Treatment - The person is provided immediate medical treatment and first aid. First aid treatment like CPR (cardiopulmonary resuscitation), the elevation of legs, and checking breathing and heart rates at regular intervals are done.

What Is Hemorrhage?

Any minor or major blood loss from a damaged blood vessel is called hemorrhage. It can occur both inside and outside the body.

• Causes:

  • Use of alcohol and tobacco-based products over a long time.

  • Clotting disorders.

  • Injury to any internal organ.

  • Physical injuries.

  • Complications during surgeries.

• Symptoms:

  • Weakness.

  • Nausea and vomiting.

  • Pain in the chest.

  • Shock.

  • Increased heartbeat and heart rate.

  • Organ failure and coma.

• Treatment - Immediate medical treatment is required based on the source of bleeding and the symptoms.

What Is Thrombosis?

The formation of a blood clot within the blood vessels results in thrombosis. Thrombus or clot formation decreases the blood supply to the organs.

• Causes:

  • Venous Thrombosis - It occurs as a result of injury to the body's deep veins, excessive weight, medicines that cause blood clotting, like birth control tablets, bedridden patients, autoimmune diseases, etc.

  • Arterial Thrombosis - It occurs as a result of calcification and hardening of the blood vessels due to calcium or fat deposition.

• Symptoms:

  • Pain and swelling.

  • Pain in the chest.

  • Change in the mental state of a person.

• Treatment - The treatment plan is based on the patient’s state and age. Blood-thinning medicines or anticoagulants, stents, and catheters are used.

What Is Embolism?

Obstruction caused in the blood supply due to the presence of a foreign particle like a blood clot or air results in embolism. The embolus can travel through the blood vessels and causes an embolism at a distant site.

• Causes:

  • Excessive weight.

  • Cardiac problem.

  • High blood pressure and diabetes.

  • Smoking.

• Symptoms:

  • Pain in the chest or sudden pain in the back region.

  • Dizziness.

  • Rapid or short breathing.

• Treatment - Anticoagulant or thrombolytic medications are given to the patient.

What Is Infarction?

Death of body tissue due to decreased blood flow or complete failure of blood supply causes infarction. The dead tissue is called an infarct.

• Symptoms:

  • Blood mixed in saliva or cough.

  • Fever.

  • Difficulty in breathing.

  • Heartbeat and heartrate in increased.

  • Feeble and dull sound when chest tapping is done.

  • Fatigue.

  • Dizziness.

• Causes - Thrombosis of the arteries is the main cause of infarction.

• Treatment - The treatment plan depends on the severity of the condition and medicines. Drugs like anticoagulants and nitroglycerine are used. Oxygen supply to the organ is resumed by external oxygen supply.

Conclusion:

Understanding the hemodynamics of the blood and body fluid and the associated disorders is important to understand the disease's cause and executing proper treatment modules accordingly. Most of these disorders are medical emergencies and need proper medical attention.