• Clinical science

Wound treatment

Abstract

Wounds are defined as a disruption of the normal structure and function of skin and underlying soft tissue that is caused by trauma or chronic mechanical stress (e.g., decubitus ulcers). Wounds can be broken down into acute or chronic, and open or closed. Wound treatment is performed according to pathology, the extent, and circumstances of the lesions. To heal, the wound needs to have a vascular supply, be free of necrotic tissue, clear of infection, and moist. General wound treatment includes surgical wound closure, open wound treatment, and plastic reconstruction of skin defects. In addition, infectious or concomitant disease prevention should be considered (e.g., antibiotic therapy, vaccines for tetanus and rabies, diabetes control). Surgical intervention is usually required with traumatic injuries, whereas chronic wounds and ulcers can often be treated conservatively. In the case of severe or nonhealing wounds, surgical intervention including debridement may be necessary. Wound complications, particularly after abdominal surgery, include hematomas and seromas, infection, dehiscence and evisceration, and fistulas of the GI tract.

Classification

Acute vs chronic wounds

  • Acute wound: a disruption of the skin and/or underlying soft tissue that has a well-organized healing process with predictable tissue repair
    • Stab wounds
    • Lacerations
    • Bruises
  • Chronic wound: a wound with an impaired healing process, usually involving a prolonged or excessive inflammatory phase, persistent infections, formation of drug-resistant microbial biofilms, and the inability of cells to respond to reparative stimuli. All chronic wounds begin as acute wounds.

Open vs closed wounds

  • Open wound: a wound with skin breakage and exposure of underlying tissue to the outside environment
    • Lacerations
    • Punctures
    • Gunshot wounds
  • Closed wound: a wound with intact skin, and underlying tissue not directly exposed to the outside environment

References:[1][2]

Delayed wound healing

Risk factors for delayed wound healing:

DID NOT HEAL

  • Drugs (e.g., steroids, cytotoxics, and other immunosuppressive agents)
  • Infections/Ischemia
  • Diabetes
  • Nutritional deficiency
  • Oxygen (hypoxia)
  • Toxins
  • Hypothermia/hyperthermia
  • Excessive tension on the wound edges/EtOH
  • Acidosis/Another wound
  • Local anesthetics

Special wounds

Amputations

An amputation is the surgical or traumatic separation of a body part from the rest of the body.

  • Complete amputation: the body part is totally severed
  • Partial amputation: some soft tissue remains connect the affected body part and the rest of the body
  • Surgical amputations: careful, controlled removal of a body part in the operating room. Commonly due to poor blood flow, most often from peripheral vascular disease (PVD). Other reasons for amputation include severe burn or accident, or cancer in a limb.
  • Traumatic amputations: Most traumatic amputations are accidental, and usually result from factory, farm, or power tool accidents. Motor vehicle accidents may also cause traumatic amputations.
    • Complete fingertip amputation: The tips of longer fingers tend to be injured more often because they are more exposed to harm.
      • Management: control bleeding by placing direct pressure to the wound → raise the injured area → gently clean the amputated part with sterile saline solution → cover with gauze dampened with saline → place in watertight bag → place the bag in an ice bath in a sealed container → head to hospital for urgent assessment
    • Reimplantation is more likely to be performed for:

Do not allow the amputated part to be in direct contact with ice, as direct contact could cause further damage.

Bite wounds

Bite wounds; (caused by animals or humans i.e., “fight bite”) are associated with an increased risk of infection, as the bacterial flora of the oral cavity hinders wound healing:

  • Common pathogens: Streptococcus, staphylococcus, Pasteurella multocida, Capnocytophaga canimorsus, Haemophilus influenzae, anaerobic bacteria
  • Rabies: : must be considered in the case of dog bites; . If rabies is suspected, active and passive immunization according to vaccine recommendations should be performed.
  • Wound management:
    • Stabilization with direct pressure to stem bleeding, and neurovascular assessment of areas distal to wound
    • Irrigation and debridement
    • Primary surgical closure if wound meets ALL of the following criteria:
      • Clinically uninfected
      • < 12 hours old (< 24 hours if on the face)
      • Locations other than the hand or foot
    • Allow spontaneous closure (secondary intention) if:
      • Cat or human bite NOT on the face
      • Puncture wounds
      • Wounds > 12 hours old (> 24 hours if on the face)
      • Bites involving the hands or feet
    • Antibiotic therapy
      • Indications: deep puncture wounds; , moderate to severe wounds with crush injury, wounds in areas with venous/lymphatic compromise, wounds on the hands/face/close to a bone or joint, wounds requiring closure; , bite wounds in the immunocompromised
      • Use broad‑spectrum antibiotics, e.g., amoxicillin and beta‑lactamase inhibitor (amoxicillin‑clavulanate) or cephalosporin of 2nd or 3rd generation
    • Tetanus protection:
      • If patient was adequately vaccinated (successful initial immunization and booster vaccinations), no need for additional protection
      • If vaccine status is outdated or unknown, see Tetanus prophylaxis.

Bite wounds should be treated with open dirty wound treatment!

Stab wounds

  • When performing first aid, do not remove the foreign body from the wound, as this could stop the object's sealing and tamponading effect. This could result in bleeding.
  • Removal in a hospital setting with staff prepared for immediate surgical intervention
  • Treatment: see Penetrating trauma

References:[3][4][5]

Decubitus ulcers

  • Definition: : an area of unrelieved pressure resulting in ischemia, cell death, and necrotic injury of epidermis and soft tissue
  • Etiology
  • Pathophysiology:
  • Classification
    • Stage 1 = intact skin with persistent erythema
    • Stage 2 = superficial skin defect (defect of epidermis and eventually dermis)
    • Stage 3= loss of all skin layers and defect of the subcutis, eventually reaching but not penetrating through the underlying fascia
    • Stage 4 = loss of all skin layers along with extended tissue necrosis and injury of muscles, bones, etc.
  • Therapy/prevention
    • Conservative management
      • Pressure relief of the affected or vulnerable area with position changes (every 2 hours); and an alternating pressure mattress
      • Skin care: keeping skin moist, preventing breakdown, as well as keeping it clean of urine and stool
      • Wound treatment (e.g., removal of necrosis, hydrocolloid dressing)
      • Secondary prophylaxis: mobilization, optimized diet, control of infection
    • Surgical management for severe cases
      • Debridement, eventually plastic reconstruction

Pressure relief and regular skin care are the most important steps for successful decubitus prevention and treatment

References:[6]

Acute wound treatment

Open wound treatment

Clean surgical wound treatment

  • Indications:
    • Age of the wound: Primary surgical wound treatment is possible up to 6–8 hours after injury. If the wound is > 8 hours old, see treatment for dirty open wounds.
    • Extent of the wound: The patient should have intact circulation, sensation, and movement.
    • Type of wound: clean, sharply defined wound with adjustable wound edges
  • Localization: Anatomical location of the wound determines healing time (e.g., head wounds heal more quickly than extremity wounds because of increased vascularity).
  • Procedure:
    1. Cleaning and disinfection
    2. Local anesthesia
    3. Inspection
    4. Excision of the wound edges and wound irrigation
    5. Tension-free adaptation of the wound edges using suture material or staples
    6. Sterile dressing and immobilization
    7. Tetanus protection
  • Additional treatment:
    • Pathogen detection: antibiotic treatment
    • Increased risk of infection: prophylactic preoperative antibiotic treatment with activity against pathogens likely to be encountered in the procedure

6–8 hours rule: Primary surgical wound treatment should not be used for injuries older than 6–8 hours because of the high risk of infection!

Dirty wound treatment

  • Indications: The goal is to remove devitalized tissue, contamination, and residual suture material that may disrupt the body's ability to heal.
    • Infected wounds; (e.g., infected surgical wounds with black, necrotic tissue; , often occurs up to 30 days post op, up to 1 year if device is implanted)
    • Wounds with foreign bodies (e.g., bullets, infected surgical wounds with remaining suture material)
    • Bite wounds and other contaminated wounds
  • Procedure
    1. Cleaning via pressured irrigation using warm, isotonic saline
    2. Debridement under local anesthesia to remove devitalized tissue and accumulated debris
    3. Ensure drainage (e.g., inlay, strip of gauze)
    4. Moist dressing and immobilization
    5. Delayed/secondary surgical wound treatment after 3–8 days
    6. Tetanus protection
  • Additional treatment:
    • Antibiotic treatment is indicated for all dirty wounds.

Closed wound treatment

Closed wounds are usually caused by blunt trauma.

References:[7][8][9][1]

Plastic and reconstructive surgery

Skin grafting

  • Skin grafts may be used to close wounds, prevent fluid and electrolyte loss, and reduce bacterial burden and infection.
  • Full thickness skin graft (FTSG)
    • Graft: epidermis and dermis (including dermal appendages), usually obtained from areas of redundant and pliable skin (e.g., groin, lateral thigh, lower abdomen, lateral chest)
    • Indications: small, uncontaminated, well-vascularized wounds
    • Advantages: good postoperative cosmetic outcome
    • Disadvantages: high risk of necrosis, secondary injury to the donor area
  • Split-thickness skin graft (STSG)
    • Graft: epidermis and upper part (¼–¾) of the dermis (without dermal appendages)
    • Indications: many uses; resurface large wounds and mucosal deficits, line cavities, close donor sites of flaps, treat large chronic wounds
    • Advantages: heals well, only superficial secondary defect in donor area, which does not have to be covered
    • Disadvantages: scar formation when graft heals, skin pigmentation change, tendency to contract, more fragile
    • Subtype: mesh graft
      • Graft can be stretched 3–6 times its original size by grid‑like incisions.
      • Suitable for large skin defects

Skin grafts are contraindicated in the case of contaminated wounds or insufficient blood supply!

Composite graft

  • Graft: a graft containing multiple structures, such as skin and other structures like muscles, bones, or cartilage
  • Indications: distal fingertip amputations, nasal reconstructions, ear reconstructions
  • Advantages: heals well, usually includes pedicle containing blood supply, aesthetically pleasing
  • Disadvantages: higher infection rate, increased risk that graft does not take compared to local flaps

References:[9]

Complications of abdominal surgical incisions

Hematomas and seromas

  • Definition: collection of blood (hematoma) or serum (seroma)
  • Pathophysiology: failure of hemostasis or coagulation
  • Clinical features:
    • Usually occurs several days after surgery
    • Either asymptomatic or can have swelling, pain, or drainage
  • Treatment:
    • Small or asymptomatic: manage expectantly
    • Large or symptomatic: exploration and drainage, followed by wound packing until granulation tissue is formed; , then closed by delayed primary intention or by secondary intention
  • Complications: : may lead to wound infections as bacteria have access to deeper layers of fascia and can multiply in the stagnant fluid

Skin and soft tissue infections

Fascial dehiscence

  • Definition: fascial disruption due to abdominal wall tension that overcomes tissue or suture strength, or knot security
  • Clinical features
  • Treatment for early dehiscence
    • Cover wound with moist dressing; wound exploration and debridement in OR
    • Can use abdominal binder to keep organs intact while en route to OR
    • Reapproximate fascial edges
    • Closure with continuous, slowly absorbable suture
  • Complications
    • Organ evisceration: abdominal organs protrude through the outer abdomen
      • If evisceration has happened, do not use binder → take to OR immediately
  • Prevention: : good surgical technique, avoid heavy lifting for 4–6 weeks after abdominal laparotomy

Early fascial dehiscence is a surgical emergency! The mortality rate is 10%.

Intestinal fistulas

  • Etiology
    • Complication of open abdominal surgery, especially when the bowel is frequently manipulated, with possible disruption of bowel anastomosis, inadvertent enterotomy, or small bowel injury.
      • Can occur as early as 8 days from initial laparotomy
    • Other causes: cancer, irradiation, IBD
  • Types
    • Enterocutaneous fistula; : abnormal communication between the small or large bowel and the skin
      • Subtype enteroatmospheric fistula: abnormal communication between GI tract and the atmosphere, associated with high morbidity and mortality
  • Complications: sepsis, fluid and electrolyte abnormalities, malnutrition
  • Treatment
    • Conservative therapy: rehydration and electrolyte repletion, antibiotics (in case of infections), nutritional support, control of fistula drainage (e.g., ostomy pouch), skin protection
      • Spontaneous closure occurs in roughly 70% of patients
    • Surgical therapy: attempted 1–4 months after trial of conservative therapy if no signs of spontaneous closure, depending on how many adverse factors (high-output fistula, diseased bowel, distal obstruction) patient have
      • Lysis of adhesions
      • Resection of abnormal or diseased bowel
      • Reanastamosis of healthy bowel

References:[10][11][12][13]