Shock – causes, symptoms, treatment, types of shock

Proven content

Shock is a general term for the failure of the body to occur due to insufficient oxygen supply to the tissues. Each such condition is life-threatening for the patient.

Shock – definition

Shock is the general term for acute heart failure. During a shock, there is a disproportion between the demand for oxygen and its amount, along with nutrients, to the body’s cells. The most common form of shock is hypovolemic shock (caused by excessive fluid loss from the body). It occurs as a result of a reduction in the volume of circulating blood as a result of external or internal hemorrhage, fluid leakage from the vessels to the tissues in massive burns, or an anaphylactic reaction (anaphylactic shock). Next to him, he can appear normovolemic shock. In this case, the circulating blood volume remains unchanged, yet the supply of blood to the tissues is not optimal, e.g. due to impaired blood flow (embolism, thrombus, intravascular coagulation) or a sudden drop in blood pressure (heart failure, peripheral vasodilation).

Pathophysiological division of shock

Among pathophysiological shocks we distinguish:

1. distributive shock, or vasogenic shock – it is characterized by the widening of blood vessels, which is accompanied by the expansion of the volume of the vascular bed and problems with blood flow, which may lead to hypovolemia. During vascular shock, the arterial system is reduced and the blood increases in volume in the veins and capillaries. The causes of this type of shock are usually: septic shock; neurogenic; anaphylactic and hormone-induced (acute adrenal insufficiency, hypometabolic coma, thyroid crisis);
2. hypovelemic shock – caused by a decrease in total blood volume which can lead to the following conditions: dehydration; decrease in plasma volume; hemorrhage (hemorrhagic shock); escape of plasma into damaged tissues or its loss due to extensive burns;
3. cardiogenic shock – is caused by low cardiac output (in failure and arrhythmia), and may also be caused by cardiac tamponade or heart transplant rejection. It manifests itself among other low pressure, low body temperature and shallow breathing;
4. obstructive shock – characterized by reduced blood flow in the following cases: cardiac tamponade; tension pneumothorax (pressure on the venous system from the outside); pulmonary embolism; acute respiratory failure; internal causes (heart tumors).

Clinical classification of shock

Regarding clinical division shock, we distinguish:

1. cradiogenic shock;
2. hypovolemic shock;
3. septic shock – is most often caused by the transfer of Gram (-) and Gram (+) endotoxins into the bloodstream during an infection. The consequence of this is damage to organs by inflammatory cytokines and metabolic disorders caused by disseminated intravascular coagulation;
4. neurogenic shock – is a condition that will appear relatively rarely. Most often, it is caused by an interruption of stimulation from the higher levels of the central nervous system to the lower elements of the sympathetic nervous system. It is for this reason that the vascular bed is dilated (often due to lateral damage to the spinal cord above the 1st thoracic vertebra);
5. anaphylactic shock – hypersensitivity of the patient’s body to certain factors (it may be food or an insect sting). During anaphylactic shock, the permeability of the capillaries increases, which in turn causes edema. The second mechanism in this type of shock is vasodilation. This state of the disease is very dangerous, as suffocation can even result from swelling in the throat or larynx.

Types of Shock

The following types of this condition are also distinguished:

• vascular shock – combines neurogenic, septic, anaphylactic types of shock. It develops with vasoconstriction, which is caused by a bacterial infection, injuries of the spinal cord or brain;
• hypovolemic – includes anhydrous and hemorrhagic shock;
• pain shock – combines burn and traumatic shock;
• cardiogenic shock;

This condition is characterized by the presence of the following stages:

• I degree or compensated – the preservation of consciousness is characteristic, the patient makes contact, but he is slightly inhibited. Has a favorable prognosis;
• II degree or subcompensated – characterized by lethargy of the patient, pallor of the skin, muffled heart sounds, shallow and rapid breathing. It is necessary to carry out anti-shock measures;
• III degree or decompensated – adynamia develops, lethargy. No response to pain. The patient speaks softly and weakly, confusion of consciousness is characteristic;
• IV degree or irreversible – a terminal condition develops. The patient is unconscious, the skin becomes marble with the presence of stagnant spots such as cadaveric. The pulse is barely palpable. The prognosis is extremely unfavorable.

Experts distinguish the following stages of shock:

stage 1, compensated or non-progressive – characterized by the preservation of perfusion of vital organs, which occurs due to compensatory mechanisms;

Stage 2 or progressive – a state develops when compensatory mechanisms are no longer able to maintain the necessary perfusion. There is a start of the progression of all pathogenetic mechanisms that lead to the development of shock;

stage of irreversible changes or stage 3 – it is not possible to improve the patient’s condition with the help of medical intervention.

Shock – symptoms

Each type of shock has its own symptoms. However, the general symptoms include:

1. bow,
2. entanglement,
3. tachycardia,
4. bradycardia during neurogenic shock,
5. systolic blood pressure below 90 mmHg,
6. shallow and quicken breathing,
7. extension of capillary return> 2 s,
8. low urine output (oliguria).

Symptoms depending on the severity of the shock

Each type of shock begins with lowered blood pressure, and thus the blood supply to the organs. Defense mechanisms emerge to help maintain normal blood pressure, but they are depleted over time, which can cause hypotension (blood pressure below 90 mmHg systolic pressure or 60 mmHg diastolic pressure). How the patient’s body reacts to tissue hypoxia can be divided depending on the degree of advancement of the shock (four stages).

1 step – balanced shock: the patient’s body activates defense mechanisms to compensate for the hypotension. When the baroreceptors in the arterial walls show a drop in pressure, there is a release of adrenaline and neoadrenaline, followed by vasoconstriction and an accelerated heart rate. The patient then develops euphoria and a higher pain threshold than before.

2 step – centralization: circulation moves to the heart, lungs and brain at the expense of muscles, gastrointestinal tract and skin blood supply. The patient develops pale skin, sweating and cold.

3 step – metabolic changes: at this stage, the patient’s life is threatened due to oxygen deficiency. Mitochondria stop synthesizing ATP, the respiratory chain is disturbed, which in turn causes an increased amount of free radicals released (free radicals destroy the cell membrane and other cellular organelles). Previously hypoxic cells undergo anaerobic metabolism, which produces lactic acid, which causes metabolic acidosis. Due to the stagnation of circulation, aggregation processes occur.

4 step – irreversible phase: during this stage, blood pressure is dangerously lowered, leading to: bradycardia, aggregation of platelets and erythrocytes, pulmonary edema, oliguria and intravascular coagulation.

Diagnostics

When the first signs appear that may indicate the development of shock, you should immediately make an appointment with a resuscitator. During the examination, a consultation with an anesthesiologist is possible.

To confirm the diagnosis, the doctor will prescribe the following studies:

• survey;
• external examination of the patient;
• measurement of blood pressure (according to the Korotkov method);

Consequences of organ ischemia

Organ ischemia in shock leads to:

1. bleeding;
2. intestinal paralytic obstruction;
3. acute prerenal renal failure;
4. digestive tract dysfunction;
5. disturbance of consciousness;
6. neurological problems;
7. severe respiratory failure;
8. severe hepatic failure;
9. disseminated intravascular coagulation;
10. sepsis (due to the penetration of microorganisms from the gastrointestinal tract into the blood).

Shock – treatment

In any case of suspected shock, medical assistance should be called. Until the ambulance arrives, emergency procedures should be implemented, depending on the cause of the shock (e.g. stopping visible hemorrhages). In case of loss of consciousness, the patient should be placed in the recovery position, protected against heat loss. In the event of cardiac arrest, perform cardiopulmonary resuscitation. The patient is not allowed to administer any medications on his own. It is also forbidden to administer any liquids – in case of loss of consciousness, there is a risk of choking.

Prevention

Prevention of this condition is the timely treatment of diseases that can lead to its development.