The reason for the occurrence of SDS may be a fall in catastrophes of the wreckage of buildings and various structures, large stones, trees, pillars, etc., as a result of which blockages are formed. In this case, the beginning of compression for the victims is a complete surprise. At this time, fear, pain, a terrible sense of doom covers them. Therefore, at the beginning of compression, a peculiar pathological condition begins to form in them – prolonged compression syndrome. The trigger in the development of SDS is pain resulting from compression of various parts of the body. Through neuro-reflex connections, pain activates the cortex and subcortical centers of the brain. As a result, the body’s defense systems are mobilized – consciousness, sensation, autonomic, somatic and behavioral reactions and emotions. Anti-stress mechanisms are also included. In particular, the hypothalamic-pituitary-adrenal system is inhibited. Under the influence of severe trauma, severe pain and stress, the protective and anti-stress mechanisms that cause the development of neuro-pain shock are depleted. Prolonged pain causes large-scale dysfunctions of various organs and systems of the body. In the process of compression, centralization of blood circulation develops, which is characteristic of traumatic shock of various origins.
Classification of prolonged compression syndrome (E.A. Nechaev et al., 1993)
a) by various objects, earth, etc .;
b) positional. Crushing. By localization Squeezing:
• limbs (limb segments). By a combination of
SDS with damage to:
• internal organs;
• bones and joints;
• trunk vessels and nerves. By severity Syndrome of mild grade Syndrome of moderate grade Syndrome of severe degree
By periods of the clinical course Compression period Post-compression period: a) early (1st – 3rd day); b) intermediate (4-18th day); c) late (more than 18 days). Combined injuries • SDS + burn; • SDS + frostbite; • SDS + irradiation with ionizing radiation; • SDS + poisoning and other possible combinations. According to the developed complications, SDS complicated by: • diseases of organs and systems of the body (myocardial infarction, pneumonia, peritonitis, mental disorders, etc.); • acute ischemia of the injured limb; • purulent-septic complications. With prolonged squeezing of tissues, pathological changes occur both in themselves and in tissues located distal to the site of pressure application. With prolonged pressure on the tissues up to 10 kg / cm2 after 7-10 hours, the outflow of lymph and blood, as well as the influx of arterial blood to them, is disturbed. Microcirculation of blood is also disturbed, stasis occurs and degenerative-necrotic changes begin to develop. During compression resulting from a pressure of more than 10 kg / cm2, as a rule, microcirculation of blood and lymph outflow almost completely stop in the tissues. As a result of this, ischemia occurs, quickly leading to impaired tissue respiration, accumulation in the tissues of products of incomplete oxidation of nutrients (especially lactic and pyruvic acids) and the development of metabolic acidosis. 4-6 hours after the start of compression, tissue destruction processes develop both at the site of compression and distal to it. When soft tissues are crushed, irreversible changes in them can occur within 5-20 minutes. VDS is also accompanied by general disorders of homeostasis.
Pathological changes that occur directly in the squeezed tissues lead to changes in other tissues and organs. In particular, precapillary stasis occurs in the skin, skeletal muscle, abdominal organs and extraperitoneal space, as well as tissue and organ hypoxia. In the intercellular space, products of incomplete oxidation of nutrients and vasoactive substances accumulate. Potassium ions and plasma leave the vascular bed. The volume of circulating blood and circulating plasma (CCP) decreases, blood coagulation increases (hypercoagulation). In addition to plasma loss, endotoxemia develops, due to the accumulation of end products of metabolism in tissues, absorption of products of tissue destruction and the development of infectious processes. Endotoxemia progresses as the barrier and detoxification functions of the body (liver, kidney, immune system) are disrupted. Endotoxicosis, in turn, exacerbates a violation of cellular metabolism, microcirculation of blood in organs and tissues, and also enhances hypoxia. Over time, the tissues themselves become the cause of intoxication, as a result of which a vicious circle appears in the body.
Therefore, the pathogenetic treatment of SDS should be aimed not only at neutralizing the primary sources of intoxication, but also at eliminating toxemia and correcting tissue metabolism. It is toxemia that can be the main cause of irreversible changes in the body of patients with SDS, and even death, because as a result of toxemia, multiple organ failure develops.