Traumatic shock

Traumatic shock is usually called a trauma-caused severe condition, accompanied by severe impairment of the functions of vital organs, primarily circulation and respiration. A similar in clinical manifestations can occur with severe blood loss, not related to trauma (hemorrhagic shock), allergic reactions, intoxication. Large losses of plasma and other liquids in diarrhea, exhausting vomiting, extensive burns, acute pancreatitis, peritonitis, intestinal obstruction, etc., cause the development of severe disorders called hypovolemic shock, the leading link in the pathogenesis of which is the decrease in the volume of circulating blood (BCC).

A condition similar to hypovolemic shock can be observed without external and internal loss of fluid as a result of a sharp expansion of the vascular bed, at which relative hypovolemia develops (the mismatch of normal bcc to the sharply increased volume of the vascular bed). This pathogenesis is typical for some forms of toxic, anaphylactic, neurogenic shock.

In the clinical picture of all these shock (or shock-like) conditions, there are many common features: pallor of the skin and mucous membranes, cold skin, anxiety, shortness of breath, frequent small pulse, decreased blood pressure, reduced bcc, cardiac output, poor blood supply to peripheral tissues.

In the pathogenesis of shock and shock-like conditions, compensatory responses to hemorrhage, hypovolemia are important. These include an increase in the tone of the vessels of the venous system and the tone of the arterioles, the development of the so-called centralization of the circulation, in which blood circulation in the brain and the heart is not disturbed. In other organs and tissues blood circulation decreases, which leads to oxygen starvation of the kidneys, liver, intestines of peripheral tissues. Hypovolemia is compensated by hemodilution - the inflow into the vascular bed of fluid from the extra-vascular space. This state is defined as the stage of relative compensation. It is observed with a decrease in BCC by 20-25% (blood loss of 800-1200 ml). If treatment is not performed, then vasoconstriction begins bypassing the blood flow from the arterioles to the venules, bypassing the capillaries. Due to hypoxia, capacitive microvessels expand. Clinically, this is manifested by a severe general condition: BP decreases below 80 mm Hg. Art. , Tachycardia increases, cardiac output decreases, urination decreases, cold spells and blanching of the skin, cyanosis progresses. With a decrease in BCC by 30-40% (blood loss of 1500-2000 ml), an initial decompensation occurs, but with proper treatment the process is still reversible.

In the stage of decompensation, which develops when the bcc is reduced by 50% or more (with a bleeding loss of 2500 ml), there is a weakening of arteriolar tone, further expansion of venules and capillaries, slowing of blood flow, and then complete blood stasis as a result of aggregation of blood elements, Blood, lifelong formation of microthrombi. The resulting increased bleeding of tissues causes suspected disseminated intravascular thrombus formation, often a symptom of the development of irreversible changes in the body. The clinical picture in this stage of shock is characterized by worsening of the patient's condition, progressive lowering of blood pressure, increased tachycardia, further decrease in BCC, cardiac output, central venous pressure. The integuments acquire a marble color, sometimes with stagnant stains such as cadaveric, urination stops. This condition rarely gives in to treatment. However, intensive therapy should be carried out in full, as it is impossible to accurately diagnose the state of irreversible shock.

If blood loss, acute hypovolemia, the main damaging factor is the violation of perfusion and oxygen supply of tissues, then in the pathogenesis of severe traumatic shock pathologic impulsation from the area of ​​injury plays a leading role. In severe infectious forms of toxic shock, the condition of patients is burdened by factors of intoxication, early metabolic disorders. The severity of the condition is aggravated, the phenomena of irreversibility of shock can develop earlier.

Emergency medical measures in the treatment of various forms of shock are in principle similar and should include measures to eliminate acute circulatory and breathing disorders. Other intensive care methods are carried out taking into account the causes of shock, the peculiarities of its pathogenesis and accompanying disorders. Treatment of traumatic, hemorrhagic and hypovolemic shock should include: intensive infusion-transfusion therapy; If necessary stop bleeding; Elimination of acute respiratory failure (in severe stages of shock or in the presence of injuries and diseases that cause acute respiratory disorders); Elimination or blocking of pain and other pathological impulses; Carrying out of pathogenetic medicamentous therapy, application of modern methods of inorganic detoxification, in particular plasmapheresis.

Intensive complex therapy, provided its early onset, prevents the development of irreversible shock. The order of actions of the doctor, who helps the patient in a state of shock, is as follows.

1. Stop bleeding. With external bleeding, it is stopped by tamponing the wound, applying a pressure bandage or clamping on the bleeding vessel, and also pressing it on outside the wound. The use of the harness is only permissible if it is not possible to stop arterial bleeding by the methods listed. Transportation of a patient who is in shock, especially hemorrhagic, is carried out only on stretchers with continued infusion therapy, which in severe shock is performed by two veins, general anesthesia (optimally - by inhalation with a mixture of nitrous oxide and oxygen in the ratios of 1: 1.2: 1 ) And mandatory immobilization of the limb in fractures; When breathing is abnormal, ventilation is performed.
2. Treatment of ODN is carried out according to the above recommendations. A special role is played by the timely diagnosis of pneumothorax (especially strenuous), in which ODN can not be eliminated without immediate drainage of the pleural cavity. At the pre-hospital stage, it is easiest to perform such drainage by puncturing the pleural cavity with a thick needle (such as DuPhoe), which immediately translates the intense pneumothorax into an open one and creates the conditions for conducting an effective ventilation. With increasing asphyxia, there may be indications for immediate tracheostomy.
3. Intensive infusion-transfusion therapy (IITT) for critical disorders of hemodynamics is the leading method of correcting acute hypovolemia. The patient is laid horizontally or with a slightly pubescent head, with a low blood pressure should raise his legs. Dot or catheterize the peripheral vein and begin infusion of the plasma-substituting solution at a rapid pace. In the hospital, the method of choice is central venous catheterization (internal jugular, subclavian, femoral), which allows monitoring of central venous pressure (CVP) and rapid massive fluid infusion. At the pre-hospital stage, this method is rarely used due to its complexity and the danger of complications. The volume of infusion fluid and the rate of its introduction should be significant. Drip infusions in the treatment of critical circulatory disorders in shock are practically useless. The volume of infusion should be much larger than the deficit of BCC, since it is necessary to fill not only the intravascular fluid deficiency, but also the water losses of tissues, as water moves to the vascular bed as a result of compensatory reaction to hypovolemia. In the first hours of treatment, especially if it was started with a delay, severe shock may require infusion at a rate of 2-4 l / h. Such a volume should be administered under the control of central venous pressure (CVP), the rapid increase of which serves as a sign of developing heart failure. If the blood pressure and CVP remains low, then increase the rate of infusion, spending it in 2-3 veins at the same time. An effective antishock effect is possessed by all plasma-substituting solutions, among which are: crystalloid solutions (5% glucose solution, 0.85% sodium chloride solution, electrolyte mixtures such as Ringer's solution, Ringer-Locke, etc.); Colloidal solutions of polysaccharides (polyglucin, reopolyglucin), gelatin (gelatin), protein preparations of blood (fresh frozen plasma, albumin). When performing intensive infusion and transfusion therapy at a prehospital stage, crystalloid and colloidal solutions should be combined in a ratio of 1: 1.2: 1, including in patients with severe blood loss. In the hospital, such patients continue infusions of plasma substitutes, combining them with transfusion of red blood cells. The transfused erythrocytes should be no more than 40-50% of the liquid being drunk, and the total amount of canned red blood cells should not exceed 1000 ml for an adult in order to avoid the development of complications (syndrome of massive transfusions, intoxication with citrate). Transfusion of whole blood is indicated only in the absence of single-group erythrocytes, lowering hemoglobin levels below 80 g / l. You should include in the infusion therapy drugs that increase the oncotic blood pressure, among which albumin is highly effective. The amount of polyglucinum should not exceed 10 ml / kg, since large amounts can disrupt hemocoagulation. In case of burn shock, infusion therapy should include components of plasma and blood, since it causes significant plasma loss. In addition, full-term long-term anesthesia and measures that reduce plasma loss of the burn surface are needed. Infusion therapy is carried out until the stabilization of systolic pressure on the numbers 90-100 mm Hg. Art. And CVP - on the numbers 50-100 mm of water. Art. Achieving a satisfactory rate of urination (> 20 ml / h) is also an indication of the recovery of peripheral circulation. If during the infusion therapy, despite a satisfactory indices of blood pressure, the patient remains sharply pale, the skin is cold to the touch, urination is less than 20 ml / h or is absent, then after the deficiency of the intravascular fluid is filled, a set of measures to normalize blood circulation in peripheral tissues and microcirculatory bed . It includes the administration of vasodilators on the background of continuing infusion with continued monitoring of hemodynamic parameters. Removal of the phenomena of centralization of blood circulation and spasm of blood vessels can be carried out after replenishment of the deficit of BCC, slowly introducing one of neuroleptic, spasmolytic or ganglion-blocking drugs. A fast and controlled effect gives an introduction of 0.25% solution of novocaine. Droperidol and diazepam (seduxen) possess a vasodilator effect. Nitrite (nitroglycerin, nitroprusside) and ganglion blockers (pentamine, hygronium) are also used in the hospital. All vasodilating and antispasmodic substances are injected slowly (drip in large dilution) with continuous monitoring of hemodynamic parameters. With aggravation of hypotension, the rate of infusion is increased, while slowing the rate of administration of vasodilators. Conducted therapy can be considered effective if the patient with stable systolic pressure 90-100 mm Hg. Art. Occurs pirozovenie and warming of the skin, begins urination with a speed of more than 20 ml / h. Carrying out infusion therapy can present great difficulties in the development of a patient with heart failure (small cardiac output syndrome). Treatment of this condition is discussed in the section on myocardial infarction. In acute heart failure in patients with various forms of shock, it is customary to use droplet administration of small doses of catecholamines. In this case, the adrenaline ampoule (1 mg) is diluted in 200-500 ml of fluid and injected at a rate at which the heart rate does not increase, and other parameters of hemodynamics (blood pressure, CVP, etc.) improve. Widespread use in the treatment of acute circulatory failure in shock have corticosteroid drugs. They are administered intravenously fractional or drip mainly to increase the sensitivity of adrenoceptors to endo- and exogenous catecholamines. In shock therapy to prevent the progression of disseminated intravascular coagulation, heparin (under the skin of the abdomen or intravenously) is sometimes administered under the control of the clotting time (not more than 15 min) and other coagulogram indices. Uncontrolled administration of heparin is dangerous. With allergic (anaphylactic) shock, as well as with neurogenic reflex shock, the disturbance of vascular tone and a significant increase in the capacity of the vascular bed are characteristic first. Relative hypovolemia arises as a result of discrepancy between the bcc and the sharply increased volume of the intravascular bed. The complex of urgent measures should include infusion therapy, the administration of corticosteroids and vasoactive substances (ephedrine, adrenaline, dopamine). In case of allergic (anaphylactic) shock, antihistamines (suprastin, dimedrol, etc.) are also used, which can increase hypotension. Therefore, they should be administered against the backdrop of initiated infusion therapy, the administration of corticosteroids and calcium preparations (10 ml of 10% chloride solution or calcium gluconate), which reduce the disturbed permeability of the vascular walls. The volume of infusion therapy is determined by the reaction and the patient's condition. If urination is restored, CVP does not exceed normal values, then a large amount of infusion can be used to maintain hemodynamics, sometimes 3-4 times higher than the amount of losses recorded. During the infusion therapy, it is necessary:
   • Constantly monitor CVP, blood pressure, pulse rate, lung status (threatening pulmonary edema);
   • Carefully measure the external loss of liquids (blood loss, urination, gastric loss in vomiting, intestinal loss with diarrhea);
   • Take into account the internal loss of intravascular fluid at the following most frequently occurring conditions: polytrauma (formation of hematomas in soft tissues), hemoperitoneum, hemothorax, gastrointestinal bleeding, acute pancreatitis (plasma loss in the retroperitoneal space), intestinal obstruction (plasma loss to the intestinal lumen).
4. Anesthesia in a state of shock is necessary in the presence of pain. It should be remembered that regional or general analgesia with low blood pressure and uncontrolled hypovolemia can lead to increased hypotension and worsening of the patient's condition. Therefore, in the early stages of treatment, conductive, local anesthesia, general analgesia, administration of antihistamines and antipsychotics should be carried out only under the protection of infusion therapy. In this case, it is advisable to give preference to local or conductive anesthesia (introduction of a local anesthetic into the fracture region, blockade of nerves and plexuses, case blockade, epidural anesthesia). General analgesia is carried out with narcotic analgesics (morphine, promedol, fentanyl) with obligatory control of the state of respiration and hemodynamics. A good analgesic effect is also provided by intravenous analgin, inhalation of general analgesia with nitrous oxide (with oxygen).
5. Great importance in the treatment of shock conditions have detoxification measures. Extracorporeal detoxification (plasmapheresis, hemosorption, lymphosorption, hemodialysis, ultra-hemofiltration) is effective both in exotoxicosis (poisoning with poisonous substances) and in endotoxicosis (infectious-septic shock, multiple organ failure). Methods of extracorporeal detoxification should be applied in a timely manner in patients with severe infectious and inflammatory processes, sepsis along with general nonspecific measures to restore impaired blood circulation and respiration. It is desirable to carry out detoxification therapy in the intensive care unit (resuscitation). In cases of severe poisoning, accompanied by typical disorders for shock, intensive general anti-shock therapy is performed in combination with specific measures, including the administration of antidotes, the use of hemosorption, etc. (see Acute poisoning).