Wound Infection

Types of suppuration and predisposing factors

The development of infection depends on the timing of contamination:

• Primary suppuration: occurs within the first 3–5 days after injury.
• Secondary suppuration: develops later due to the emergence of new foci of necrosis or secondary infection with hospital strains (superinfection).

The probability of infection development is influenced by:

1. Nature of the wound: tissue crushing and contusion (especially on the lower extremities), severe contamination with soil or clothing fragments.
2. Circulatory disorders: damage or ligation of main vessels, compression by a tight bandage or tourniquet.
3. Decreased body resistance: hypothermia, anemia, shock, starvation, avitaminosis, poor transport immobilization.

Clostridial (gas gangrene)

Anaerobic clostridial infection runs a severe course and is classified by prevalence (localized and generalized) and clinical course (fulminant, rapidly or slowly progressive).

Clostridial panniculitis (cellulitis): Characterized by slow progression and local involvement. Pain is mild, intoxication is moderate. Gas accumulation around the wound and a sero-putrid foul-smelling discharge are noted.

Clostridial necrotic myositis (classic gas gangrene): Proceeds violently, incubation period ranges from several hours to 2 days. Differs by rapidly increasing severe intoxication. Local changes:

• Progressive edema smoothing out skin folds.
• Skin is initially pale yellowish, then bronze or greenish-blue spots appear.
• Epidermis detaches, forming bullae (blisters) with transparent/turbid contents.
• Muscles turn gray ("boiled meat appearance") and bulge from the wound.
• Gas accumulates in the muscles and subcutaneous tissue.

Non-clostridial and putrid infection

Besides clostridia, the wound can be colonized by other microorganisms, altering the clinical picture.

Putrid infection: Characterized by the absence of granulation in a dry wound, gray muscles with progressive necrosis, and a specific discharge odor. The odor depends on the pathogen: Clostridium sporogenes produces a smell of rotting meat, E. coli and Proteus vulgaris produce an ammonia smell. Pus color is dirty gray or brown. An early sign is recurrent chills without pain.

Non-clostridial anaerobic infection: Accompanied by severe intoxication (anemia, tachycardia, scleral icterus), abundant necrosis, and dirty-gray pus with fat droplets. Unlike gas gangrene, local manifestations are less pronounced: there is no bronze skin discoloration, muscles do not resemble "boiled meat", and gas accumulation (crepitus) is rare.

Exudate color indicates the type of flora: Pseudomonas aeruginosa produces a blue-green color, viridans streptococci produce green.

Surgical treatment: SSD

If a wound has suppurated, secondary surgical debridement (SSD) is performed under anesthesia. The goal of the surgery is to remove pus, excise necrotic tissues, and ensure drainage.

Stages of SSD:

1. Revision: assessment of the extent of necrosis, search for pockets and foreign bodies.
2. Removal of pus.
3. Necrectomy: excision of dead tissues (sometimes using ultrasonic cavitation or laser).
4. Opening of pockets and purulent collections.
5. Sanation: copious irrigation with antiseptics (chlorhexidine, hydrogen peroxide) and drying.
6. Drainage: placement of drains through counter-incisions (additional cuts).
7. Tamponade: loose packing with tampons containing proteolytic enzymes.

General treatment includes antibacterial, detoxifying, and anti-inflammatory therapy.

Briefly: answers to topical questions

Class and exam questions

What else to study on this topic

• Local treatment of a purulent wound according to the phases of the wound process
• Features of staphylococcal wound infection
• Dynamics of the inflammatory process in the wound
• Classification of gas gangrene by clinical and morphological manifestations

Other topics in "CHAPTER 10. GENERAL ISSUES IN TRAUMATOLOGY"

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.