Gangrene is the necrosis of living tissues (parts of organs or parts of the body). It can affect any organs and tissues: skin, muscles, subcutaneous tissue, lungs, gallbladder, intestines, etc. It is manifested by pain in the affected area, followed by the disappearance of sensitivity, characteristic external changes. With wet form, pronounced intoxication is noted, there is a tendency to spread the infectious process. The diagnosis is made based on the clinical picture. Treatment – necrectomy, amputation or exarticulation of the affected segment.
R02 Gangrene, not classified elsewhere
Gangrene is necrosis of parts of the body or parts of organs, in which there is a characteristic change in the color of the affected tissues. Due to the destruction of hemoglobin and the formation of iron sulfide, they turn black, bluish or dark brown. Pathology can affect any tissues and organs, often develops in the area of distal (distant from the center) segments. Tissue necrosis is caused by the cessation or sharp deterioration of blood supply or destruction of cells. At the same time, the immediate causes can be very different – from exposure to microbes to allergies or damage as a result of excessive heating or cooling.
Gangrene develops as a result of direct exposure to toxic, chemical, mechanical, radiation, electrical, thermal and other factors on the tissues. All causes can be divided into four large groups.
- Physical effects. Mechanical force causes gangrene with sufficiently extensive injuries (ruptures or fractures), in which a large number of cells or even entire organs are destroyed. Temperature exposure causes gangrene when the temperature rises above +60C or less than – 15C; in the first case, a burn occurs, in the second – frostbite. The mechanism of this disease development in case of electric shock is similar to burns: a significant increase in temperature occurs at the outlet of the current, literally burning tissue.
- Chemical effects. Acids cause the coagulation of cellular proteins and cause the development of dry gangrene. When exposed to alkalis, saponification of fats and dissolution of proteins occurs, colliquational necrosis (melting of tissues) develops, resembling wet gangrene in nature.
- Infectious effects. Gangrene usually develops with gunshot or deep stab wounds, as well as with crushing, crushing of tissues, etc. However, due to the concomitant disruption of tissue nutrition, it can occur with small wounds or even abrasions in patients suffering from diabetes mellitus. Gangrene can be caused by Enterobacteria, E. coli, streptococci, proteus and clostridia. In the latter case, gas gangrene develops.
- Circulatory disorders. They are the most common cause of gangrene. Blood supply disorders can develop with serious cardiac disorders (decompensation), blockage or prolonged vascular spasm with atherosclerosis, embolism, vascular sclerosis, obliterating endarteritis or ergot poisoning.
Often the reason for the cessation of blood circulation is injury or mechanical compression of the vessel. For example, when a hernia is pinched, gangrene of the intestine may develop, with an excessively tight plaster cast or excessively prolonged tourniquet, necrosis of the limb may occur. The same group of gangrene can include cases of traumatic damage to large vessels as a result of wounds while maintaining the integrity of tissues.
There are a number of factors that influence the likelihood of the development and features of the course of gangrene. A more rapid and rapid course is observed in disorders of the general state of the body due to exhaustion, intoxication, vitamin deficiency, acute or chronic infectious diseases, anemia, hypothermia, diseases accompanied by disorders of blood composition and metabolism.
The local features affecting the development of gangrene include the condition of the vessel walls (changes due to sclerosis or endarteritis), the type of structure of the vascular system (loose, with a large number of anastomoses and collaterals, in which the probability of gangrene decreases or the trunk, in which disease can develop if only one vessel is damaged), as well as the degree of differentiation of tissues (highly differentiated tissues, for example, brain or lung, tolerate damage worse than low-differentiated ones, for example, fat).
Infection of tissues aggravates the course of the process, promotes the transition of dry gangrene to wet and causes the rapid spread of necrosis. Excessive cooling causes vasospasm, which further aggravates circulatory disorders and promotes the spread of necrotic changes. Excessive warming stimulates the metabolism in the tissues, which in conditions of insufficient blood supply also leads to an acceleration of the process of gangrene development.
Taking into account the consistency of the dead tissues and the features of the clinical course, dry and wet form are isolated. Wet gangrene is prone to a more severe course and often poses an immediate danger to the patient’s life. Taking into account etiological factors, gangrene is divided into infectious, toxic, allergic, ischemic, etc. In addition, gas gangrene is isolated, which is caused by anaerobic microorganisms, affects mainly muscle tissue and has certain flow characteristics.
As a rule, dry gangrene develops in cases of gradual disruption of blood supply. It is more often observed in dehydrated, emaciated patients, as well as in patients with a dry physique. It is usually limited, not prone to progression. Tissues with this form of gangrene shrink, dry out, decrease in volume, thicken, mummify, turn black with a bluish tinge or dark brown.
In the initial stages of disease, the patient experiences severe pain in the limb area. The skin in the affected area first turns pale, then becomes marbled, cold. The pulse in the peripheral arteries is not determined. The limb becomes numb, sensitivity is impaired, but pain persists even during the period of pronounced necrotic changes. Prolonged pain in gangrene is caused by a prolonged period of preservation of nerve cells in the foci of decay and compression of nerve trunks due to reactive edema of tissues located proximally (closer to the center of the body) from the lesion.
Dry gangrene begins in the distal (remote) parts of the limb, and then spreads upwards to a place with normal blood circulation. A demarcation shaft is formed at the border of the affected and healthy tissues. If the necrotic area is not removed surgically, it is gradually rejected by itself, but this process takes a long time.
At the initial stages, it is very important to prevent the transition of dry gangrene with its relatively favorable course into a more dangerous and severe form – wet gangrene. Therefore, before the drying of the tissues, it is necessary to ensure strict compliance with the rules of asepsis. The affected areas are covered with dry sterile napkins, regular dressings are carried out.
The decay of necrotic tissues in dry gangrene is practically not pronounced. The small amount of absorbed toxins, the absence of intoxication and the satisfactory general condition of the patient make it possible not to carry out early surgical treatment. Surgical intervention in this form of gangrene is usually performed only after the demarcation shaft is fully formed.
Wet gangrene usually develops in conditions of sudden, acute disruption of the blood supply to the affected area. Full, “loose”, pasty patients are more prone to this form of gangrene. In addition, wet gangrene occurs with necrosis of internal organs (lungs, intestines, gallbladder).
With wet gangrene, necrotic tissues do not dry out. Instead, a focus of putrefaction is formed. Decay products from this focus are absorbed into the body, causing severe intoxication and seriously disrupting the general condition of the patient. Microorganisms multiply intensively in dead tissues. Unlike dry gangrene, with wet necrosis, necrosis quickly spreads to neighboring areas. The demarcation shaft is not being formed.
At the initial stages of the development of wet gangrene, the skin on the affected area becomes pale, cold, then acquires a marble color. There is significant swelling. Dark red spots and blisters of the exfoliated epidermis appear on the skin, when opened, the sucrovich contents are released. On examination, the bluish venous network is clearly visible. The pulse in the peripheral arteries disappears. Subsequently, the affected area turns black and disintegrates, forming a fetid grayish-green mass.
The condition of a patient with wet gangrene deteriorates dramatically. There are marked pains, a decrease in blood pressure, an increase in pulse, a significant increase in temperature, lethargy, lethargy, dry mouth.
Due to the deterioration of the general condition and intoxication caused by the absorption of tissue breakdown products, the body’s ability to resist infection sharply decreases. Gangrene spreads rapidly, seizing the overlying departments. In the absence of timely specialized care, sepsis develops and death occurs. Especially severe gangrene is observed in patients with diabetes mellitus. This is due to the deterioration of microcirculation, metabolic disorders and a decrease in the overall resistance of the body.
To prevent the spread of infection with wet gangrene, the removal of the affected tissues (amputation or necrectomy) is performed at the earliest possible time.
Gangrene of internal organs
Clinical signs of gangrene of internal organs depend on the localization of the pathological process. In conditions caused by necrosis of the abdominal organs, symptoms of peritonitis are observed: fever, intense abdominal pain, nausea and vomiting that do not bring relief. On examination, a sharp pain is detected when pressing. The muscles of the anterior abdominal wall are tense. Specific symptoms are determined (Shchetkin-Blumberg, Voskresensky, Mendel). A characteristic feature is a symptom of imaginary well–being – a sharp pain at the moment of perforation, which then decreases, and after 1-2 hours increases again.
With gangrene of the lung, there is a high temperature, torrential sweats, lethargy, increased pulse rate and a decrease in blood pressure. The patient’s condition is severe and rapidly deteriorating. When coughing up, fetid sputum is released, which, when settling, is divided into three parts: the lower one is a thick, crumbly mass (destroyed lung tissue), the middle one is a brown liquid with an admixture of blood and pus, and the upper one is foamy. Multiple wet wheezes are heard in the lungs.
Treatment is carried out in a hospital setting and includes general and local activities. When gangrene occurs due to the effects of chemical and mechanical factors (limb crushing, burns, frostbite, etc.), the patient is referred to orthopedic traumatologists.
The choice of the department for other types of gangrene depends on the localization of pathology: the treatment of gangrene of the abdominal organs (pancreas, appendix, gallbladder, intestines), as well as gangrene of the extremities in diabetes mellitus are surgeons (department of general surgery), the treatment of lung gangrene – thoracic surgeons, the treatment of gangrene caused by vascular pathology – vascular surgeons.
A patient with gangrene is prescribed bed rest. Take measures to stimulate blood circulation and improve tissue nutrition. To eliminate reflex spasm of collateral vessels, novocaine blockades are performed according to indications.
General therapeutic measures are carried out to improve the function of the cardiovascular system, fight infection and intoxication. Intravenous injection of solutions, plasma and blood substitutes is performed, if necessary, blood transfusion. Antibiotics and cardiac medications are prescribed.
With gangrene developed as a result of vascular damage, one of the most important tasks is to restore blood circulation in still viable tissues. With thrombosis, thrombolytic drugs are prescribed. If necessary, surgical interventions are performed on the arteries.
The tactics of local treatment depends on the type of gangrene. In case of dry gangrene, conservative therapy is carried out at the initial stages. After the formation of the demarcation shaft and the mummification of the necrotic area, amputation or necrectomy is performed. The amputation level is chosen in such a way as to preserve the function of the limb as much as possible and at the same time provide favorable conditions for the healing of the stump. During surgery, the distal part of the stump is immediately closed with a skin-muscle flap. Healing occurs by primary tension.
With wet gangrene, immediate excision of necrosis within healthy tissues is indicated. Necrectomy or amputation is performed on an emergency basis. The limb is cut off by the guillotine method. The formation of the stump is carried out after cleansing the wound. In case of gangrene of internal organs, an emergency surgical intervention is performed to remove the necrotic organ.
Prognosis and prevention
The prognosis for the preservation of the affected area is unfavorable, for life with dry gangrene is favorable. The outcome of wet gangrene depends on the prevalence of the lesion and the presence of complications. Measures to prevent gangrene include early diagnosis and timely treatment of diseases that can cause the development of necrosis. In case of injuries, infection prevention is carried out, measures are taken to improve the blood supply to the affected area.
- Glattlly H.W. Aging and amputations // Artif Limbs. — 1996; 10: 1.
- Geertzen J.H.B., Martina J.D., Rietman H.S. Lower limb amputation. Part 2: Rehabiliation: a 10 year literature review // ProstheOrthotlnt. — 2001; 25: 14. link
- Collin C. Mobility after lower limb amputation // BrJurg. — 1995; 82: 1010.
- Kay H.W., Newman J.D. Relative incidence of new amputations: statistical comparisons of 6000 new amputations // Orthot Prosthet. — 2005; 29: 3.
- Maggio P.M., Carvalho C. Sepsis // MSD Manual. — 2018.