7.1. Wound infection
With the development of inflammatory complications, it is customary to isolate purulent, putrefactive, and anaerobic infections. The last two types are considered special forms of wound infection, which also include tetanus and some other rare nosologies.
Purulent wound infection
This type of infection is the most common. The causative agent is mainly Staphylococcus, which in 60-70% of cases is identified in association with other microorganisms.
Purulent infection includes a complicated course of wounds of various types: purulent leaks, phlegmon, abscesses (including post-injection), fistulas, lymphadenitis, thrombophlebitis, osteomyelitis, etc.
It is advisable to distinguish early complications that occurred in the nearest time after the injury (after 1-3 days), and late complications (over 3 days).
Early complications
There are both general signs of intoxication and local symptoms (twitching and shooting constant pains, increased edema, local hyperemia, and hyperthermia). There are five "classic" signs of purulent inflammation:
- dolor (pain);
- calor (local hyperthermia);
- rubor (local hyperemia);
- tumor (swelling, edema);
- functio laesa (dysfunction).
In the presence of these signs, measures should be taken to detect the focus of inflammation and drain it (incision, or sutures releasing).
In cases of deep inflammation (for example, with suppuration of an intermuscular hematoma), imaging aids such as U/S and MRI are helpful. A diagnostic puncture is also used in the supposed area of the abscess.
Late complications
In most cases, late complications are accompanied not only by local manifestations associated with wound suppuration but also by general changes (intoxication, decreased immunity, impaired protein and water-electrolyte balance) that require mandatory correction. With the generalization of infection against the background of decreased immunity, prolonged course of the wound process, sensitization to the pathogen, sepsis with hyperthermia (40-41 °C), anemia, protein deficiency may develop.
Bacteremia is considered one of the main signs of sepsis. However, for a short period, transient bacteremia can develop even after tooth extraction, although without sepsis development. At the same time, only in 80% of cases with a detailed clinical picture of sepsis, laboratory data confirm bacteremia.
Treatment of infectious wound complications
Local treatment is carried out, considering the stage of the wound process. It includes cleaning the wound (mechanical and chemical) from non-viable tissues, suppressing microflora, creating favorable conditions for reparative processes.
Both chemical and biological preparations (proteolytic enzymes, antiseptics, salt solutions, antibiotics), and physical methods of exposure (local application of sorbents, quartz treatment, vacuuming, ozonation, treatment with ultrasound, laser, electric currents) are used. In recent years, special wound coatings based on collagen, alginate and other substances that stimulate reparative processes do not injure the wound surface during the change of dressing and have a significant sorption capacity are widely used. They are significantly superior to traditional ointment and gauze dressings.
A method of early active surgical treatment of purulent wounds has been developed, when, without waiting for a sequential change of all phases of the wound process, a number of repeated surgical treatments is performed using VAC-therapy (vacuum-assisted closure) - permanent vacuuming of wound.
A special role is assigned to general strengthening and detoxification therapy, restoration, and maintenance of the protein-electrolyte balance. With purulent discharge, a large amount of protein is lost, intoxication leads to the development of anemia. With a violation of homeostasis, the reparative processes are slowed down, distorted, and wound healing becomes problematic.
Anaerobic infection
The causative agents are four types of clostridia - Cl. perfringens, Cl. oedematiens, Cl. histolyticum and Cl. septicum, which secret exotoxins that cause necrosis of connective tissue and muscles, as well as hemolysis of erythrocytes, vascular thrombosis with damage to the myocardium, liver, and kidneys. The development of clostridial infection is characterized by gas formation and the development of pronounced edema.
Gas gangrene is one of the most life-threatening complications. It is believed that it has been most widespread in the wartime (up to 1.5% of all wounds); however, even in peacetime, one should remember about the possibility of a Clostridial wound infection, especially since there are objective prerequisites for this. Anaerobes are found in more than 70% of all wounds. However, infection develops only in 1-2% of cases. Therefore, special conditions are needed for its development, which include:
- abundant contamination of the wound with ground, the presence of foreign bodies;
- the presence of a nutrient medium for microflora (untimely or poorly performed PST of the wound);
- anaerobic conditions in the wound (application of a hemostatic tourniquet for a long time, the presence of blind cavities, suturing the wound tightly without indications, tight long-term tamponade of the wound, damage to the main vessels);
- incomplete transport immobilization.
In 50% of the victims, the first signs of anaerobic infection are traced within the next 3-5 days after injury. However, the incubation period may be longer (up to 2-3 weeks) or only a few hours.
Clostridial wound infection is a highly contagious disease. Therefore, even if gas gangrene is suspected, it is necessary to observe a strict anti-epidemic regime, and at the slightest suspicion of an anaerobic infection, completely isolate the patient.