According to abbreviationfinder, hypovolemic shock is a severe circulatory disorder that can lead to death if left untreated. The cause is usually a loss of blood or fluid, for example due to severe diarrhea or bleeding after an accident.
What is hypovolemic shock?
If the blood volume decreases due to blood or fluid loss, the body first tries to stabilize the circulation by increasing cardiac output.
In colloquial language one often speaks of shock as a result of a situation with extreme psychological stress. In medicine, however, the term hypovolemic shock refers to an acute lack of oxygen in vital organs such as the lungs or kidneys. The relationship between oxygen demand and the supply of oxygen is no longer correct.
Due to a lack of volume, there is a centralization of the remaining blood volume and thus reduced blood flow to the smallest blood vessels (capillaries). Due to the lack of blood circulation, there is a lack of oxygen and the cells are damaged and thus the entire organ is damaged. This can lead to a loss of function of the affected structures.
The cause of hypovolemic shock is volume depletion. It occurs when blood is lost by more than 20 to 30 percent of the total blood volume and by other fluid losses. Hypovolemic shock caused by blood loss is also referred to as hemorrhagic shock.
Injuries to vessels, for example due to cuts or the rupture of an aneurysm, i.e. a bulging of the main artery, can result in massive blood loss and thus cause hypovolemic shock. Bleeding in the gastrointestinal tract, for example due to gastric ulcers or tumors in the intestines, can be so massive that the blood volume is no longer sufficient to supply the body completely.
Another source of heavy bleeding is acute severe inflammation of the pancreas (pancreatitis). Other causes of profuse bleeding that can trigger hypovolemic shock are fractures of well-perfused bones, such as a pelvic fracture or femoral fracture. The rupture of the spleen, for example after an accident or accidental injuries to other organs, can lead to bleeding into the abdomen and thus to a volume loss that can no longer be compensated.
Complications at birth or during operations also harbor the risk of life-threatening blood loss. However, not only the loss of blood, but also the loss of water, plasma or electrolytes can lead to a volume depletion shock. Possible causes here are losses due to severe vomiting, diarrhea, dehydration due to insufficient fluid intake or disturbances in the hormonal balance with increased water loss (e.g. adrenal insufficiency | Addison’s disease).
In the case of severe inflammation of the peritoneum or pulmonary lining, as well as extensive burns, the loss of plasma water into the tissues can be so severe that hypovolemic shock develops.
Symptoms, Ailments & Signs
If the blood volume decreases due to blood or fluid loss, the body first tries to stabilize the circulation by increasing cardiac output. In addition, adrenaline and noradrenaline are released to constrict the blood vessels. Adrenaline also makes your heart beat faster. These measures result in a redistribution of the residual blood.
The blood is withdrawn from non-essential organs and body structures such as the skin, arms and legs, gastrointestinal tract and kidneys in order to be able to supply indirectly vital organs such as the brain, heart and lungs. This process is known as circulatory centralization.
Patients who are in shock or about to be in shock are usually very restless and anxious. Due to the release of adrenaline and noradrenaline, the pulse rate increases to more than 100 beats per minute. The patients get cold sweats. Blood pressure is low due to low blood volume and is below 90mmHg systolic. If the circulatory system has already centralized, the pulses in the body’s periphery, for example on the wrist or foot, can no longer be felt.
Due to the reduced blood flow to the skin, those affected are pale gray and feel cold. The skin and mucous membranes are colored blue (cyanotic) due to the lack of oxygen. The urine excretion is limited or completely stopped due to the functional impairment of the kidneys. Shortness of breath or hyperventilation occurs. A strong feeling of thirst is also typical of hypovolemic shock.
Diagnosis & course of disease
The diagnosis of hypovolemic shock is usually based on the typical clinical picture coupled with the symptoms of the possible cause. The shock index can be used to assess the dangerousness of the situation. The shock index is the quotient of pulse rate and systolic blood pressure. In healthy people, this index is around 0.5, in shock the value rises to over 1, which means that the pulse is higher than the systolic blood pressure.
The Rekap test is used to diagnose the peripheral blood flow situation. The examiner presses the nail of the affected person briefly into the nail bed. This forces blood out of the capillaries. If the capillarization, i.e. the backflow of blood into the capillaries, lasts longer than one second, it is assumed that there is insufficient blood flow in the periphery.
If the shock is not treated by a doctor, the patient usually dies. For this reason, immediate treatment is necessary to keep the patient alive. There is a severe loss of blood and fluid. If these losses continue and are not stopped immediately, the internal organs and heart can no longer function.
Furthermore, the organs are not supplied with enough oxygen, so that consequential damage can occur, which is usually irreversible. Due to the low blood pressure, the patient loses consciousness and can suffer various injuries from a fall. Shortness of breath occurs, which is usually accompanied by hyperventilation.
Treatment for shock is symptomatic and focuses primarily on stopping bleeding and fluid loss. If done quickly enough, the victim may survive. However, it cannot be predicted whether the shock will cause irreversible damage to the organs or the brain. This can lead to paralysis or other sensory disorders, for example. Life expectancy can also be reduced by the shock.
When should you go to the doctor?
In the event of hypovolemic shock, an ambulance must be called immediately. The patient requires immediate intensive care treatment. If blood pressure suddenly drops and shortness of breath occurs, the emergency services must be called. A strong feeling of thirst that cannot be eliminated by drinking liquid is also typical of the shock reaction. If symptoms are noticed, there may be underlying hypovolemic shock that needs medical evaluation and treatment. If you have severe cuts or signs of an aneurysm, see a doctor immediately.
People who suffer from stomach ulcers or tumors in the intestine are also among the risk groups. Patients suffering from inflammation of the pancreas should speak to their doctor if they experience the symptoms mentioned. In the case of hypovolemic shock, emergency medical help is always required. Other contacts are the general practitioner or an internist. Individuals experiencing a shock reaction associated with an existing medical condition should speak to the physician in charge.
Treatment & Therapy
The most important therapy for volume depletion shock is rapid fluid replacement. This is usually done by supplying isotonic infusion solutions. In the case of hypovolemic shock caused by blood loss, stopping the bleeding is of course the main focus of treatment. In addition, any damaged organs must be treated.
The occurrence of a shock kidney, i.e. kidney failure in shock, must be prevented at all costs. The same applies to the shock lung. The shock position is recommended as the first measure in hypovolemic shock. The patient is laid down and the legs are elevated. This leads to a backflow of blood from the legs and thus to a larger blood volume in the upper body.
To prevent hypovolemic shock, adequate fluid intake should always be ensured in the event of severe infections, diarrhea or vomiting. Obvious bleeding should be stopped as soon as possible. In any case, even if there is a mere suspicion of a volume deficiency shock, the emergency doctor must be informed immediately.
After the primary measures in hypovolemic shock, the aim is to return to normal. For this purpose, the patients receive erythrocyte concentrates and, depending on the situation, fresh plasma. A volume substitution also supports the recovery of the affected person. For further follow-up treatment, it is important that there is an intensive discussion between the doctor and the patient.
In this way, the endangered people learn details worth knowing, which relate, for example, to the correct behavior in the event of a state of shock. If family members and friends are informed accordingly, worse consequences can be avoided. For good blood circulation in the upper body, the patient’s legs should be slightly higher.
Especially in the case of an infection that is accompanied by nausea, special precautions must be taken. Sufficient fluid intake plays a vital role here. Open bleeding also requires increased attention. A precise boundary between first aid, aftercare and prophylaxis cannot be drawn here.
Persons with a corresponding indication should learn to consciously perceive their own body so that they can react quickly to any warning signs. In close cooperation with the doctor, other symptoms such as kidney failure can also be avoided. If there is trauma associated with the shock, therapeutic support may also be needed.
You can do that yourself
If a hypovolemic shock occurs, the emergency doctor must be alerted immediately. The cause of the shock must then be determined and, if possible, corrected, for example by stopping a bleed or immobilizing a broken bone. The patient must be calmed down and should, if possible, go into the shock position – legs about 20 to 30 degrees higher than the rest of the body. The emergency services will administer oxygen to the injured person and take him to a hospital for further treatment.
The further self-help measures are based on the injury. In the case of broken bones and similar injuries, rest is the first priority. The wound should be cared for according to the doctor’s instructions in order to avoid wound healing disorders and other complications. At the same time, the injury must be regularly examined by the doctor responsible. Sometimes the patient also needs therapeutic help to process a trauma. The further steps depend on the physical and mental condition of the person concerned and the healing process of the triggering injury.