Understanding Soft Tissue Injuries
Soft tissue injuries involve damage to the skin, subcutaneous tissue, muscles, tendons, ligaments, blood vessels, and nerves. These injuries range from minor abrasions requiring only cleaning and a bandage to life-threatening crush injuries with rhabdomyolysis and compartment syndrome. Proper assessment determines the severity of the injury, identifies associated injuries, and guides appropriate treatment and transport decisions.
The skin is the body's largest organ and serves as a barrier against infection, a regulator of body temperature, and a sensory organ. When skin integrity is compromised, the patient is at risk for fluid loss, infection, and hypothermia. The depth and extent of soft tissue injury determine the severity of these risks.
Types of Soft Tissue Injuries
Closed Injuries
Closed soft tissue injuries occur when energy is transferred to the tissue without breaking the skin:
- Contusion (bruise): Damage to blood vessels beneath intact skin, causing blood to pool in the tissue. Pain, swelling, and discoloration (ecchymosis) develop over hours. Large contusions may represent significant blood loss.
- Hematoma: A collection of blood under the skin that forms a palpable lump. Larger than a contusion and represents more significant vascular damage.
- Crush injury: Occurs when tissue is compressed by heavy objects for an extended period. The danger is not just the mechanical damage but the metabolic consequences: crushed muscle releases myoglobin (which can damage the kidneys), potassium (which can cause cardiac arrhythmias), and acids. Crush syndrome can develop when compression is released, sending these toxic metabolites into circulation. For patients trapped for more than 30 minutes, establish IV access and administer normal saline before releasing the compression if possible, and monitor the cardiac rhythm closely.
Open Injuries
Open soft tissue injuries break the skin and expose underlying tissue. Management priorities include hemorrhage control, wound protection, and prevention of contamination. For all open wounds, apply direct pressure with sterile dressings for bleeding, irrigate with clean water if contamination is present and time permits, cover with sterile dressings, and document wound characteristics (size, depth, contamination, associated injuries).
Compartment Syndrome
Compartment syndrome occurs when swelling within a muscle compartment (bounded by fascial layers that do not stretch) increases pressure to the point where blood flow to the muscles and nerves is compromised. It most commonly affects the lower leg (anterior compartment) and forearm. The classic presentation includes pain out of proportion to the visible injury, pain with passive stretch of the affected muscles (the most sensitive early finding), paresthesia (numbness and tingling), and eventually pulselessness and paralysis (late findings that indicate tissue is already dying). Compartment syndrome is a surgical emergency requiring fasciotomy (cutting open the fascial compartment to relieve pressure). Splint the extremity in a neutral position, do not elevate above the heart (this reduces perfusion pressure), and transport urgently.
Infection Prevention
While definitive wound care occurs at the hospital, prehospital actions can reduce infection risk. Use sterile technique when applying dressings. Do not touch the surface of the dressing that will contact the wound. Irrigate contaminated wounds with clean water if scene time permits. Cover all wounds with sterile dressings. Document the wound's condition on arrival including the presence of contamination, foreign bodies, and tissue viability. Patients with contaminated wounds, animal or human bites, and crush injuries are at particularly high risk for infection and should be informed that they may need antibiotics and tetanus prophylaxis at the hospital.