Soft Tissue Injuries: Mechanisms, Healing, and Management

Purpose: This briefing document summarizes the key themes, important ideas, and facts presented in the provided source regarding soft tissue injuries. It covers the mechanisms, structure and function of the skin, wound healing, complications, types of wounds, specific injuries (crush, blast), assessment, treatment, bandaging, bleeding control, and management of specific scenarios.

Main Themes and Important Ideas/Facts:

1. Incidence, Mortality, and Morbidity of Soft Tissue Injuries:

•Soft tissue injuries can result from various mechanisms including blunt injury, penetrating injury, barotrauma, and burns.

•Burns are identified as a "Leading form of injury."

•Death from soft tissue injuries can occur due to "hemorrhage or infection."

2. Structure and Function of the Skin (The Integument):

•The skin is a "Complex organ" with a "Crucial role in maintaining homeostasis."

•Its key functions include:

◦Protecting underlying tissue.

◦Aiding in temperature regulation.

◦Acting as a "watertight seal."

◦Serving as a sense organ.

3. Skin Tension Lines:

•The tautness of the skin varies by body region.

•Static tension: Found in areas with limited mobility. Parallel lacerations tend to close better than perpendicular ones in these areas.

•Dynamic tension: Found in areas over muscle. "Open injuries interfere with healing" in these regions due to movement.

4. Wound Healing:

•Wound healing is a "Natural process" involving "Several overlapping stages," and the injured area "may not be restored" to its original state.

•The stages include:

◦Hemostasis: "Primary concern" involving "Constriction of the blood vessels" and the action of "Platelets."

◦Inflammation: Characterized by the release of "Chemotactic factors (released by Macrophages)," and the involvement of "Granulocytes and macrophages," "Lymphocytes," and "Mast cells."

◦Epithelialization: "New epithelial cells move into injured region," originating from "Stratum germinativum cells."

◦Neovascularization: Formation of "New blood vessels" and "New capillaries bud" to provide a "Conduit for oxygen and nutrients" and a "Pathway for waste removal."

◦Collagen synthesis: Production of "Tough, fibrous protein" vital for "structural repair," synthesized by "fibroblasts" to "Provide stability."

5. Alterations of Wound Healing:

•Anatomical factors: Repeated motion and arrangement relative to skin tension lines can affect healing.

•Systemic factors: Medications and medical conditions can also alter wound healing.

•High-risk wounds: Include "Bites," wounds with an "Embedded foreign body or object," "Injection wounds," those with "Devitalized tissue," "Crush wounds," and those in "Immunocompromised patients" or patients with "poor peripheral circulation."

•Abnormal scar formation: Results from "Excessive collagen formation," leading to "Hypertrophic scar" or "Keloid scar."

•Pressure injuries: Occur in "Bedridden," "Unconscious or immobilized patient."

•Wounds requiring closure: Include those in "Cosmetic areas," "Gaping wounds," "Degloving injuries," "Ring injuries and skin tears." Closure methods include sutures, staples, or medical glue, aiming at "Bringing the wound edges together." Different types of closure are "Primary closure," "Secondary intention," and "Tertiary closure (delayed primary closure)."

•Infection: Can occur with "Any break in skin," leading to "Delay in healing" and "Additional complications," potentially including "Systemic infections." Visible and systemic clues may be present.

•Gangrene: Caused by bacteria like "Clostridium perfringens," can occur if wounds are not treated.

•Tetanus: Caused by "Clostridium tetani," a "Potent toxin" leading to "Lockjaw," but is "Rare."

•Necrotizing fasciitis: A rare but serious "Death of tissue from bacterial infection" (e.g., "Staphylococcus aureus and hemolytic streptococci") with a high "Mortality rate ranges from 70% to 80%." A key sign is "abnormally severe pain; you may see central wound necrosis with surrounding severe pain."

6. Closed Versus Open Wounds:

•Closed wounds: "No break in the epidermis," such as a "Contusion."

•Open wounds: "Disruption in the skin," making them "Vulnerable to infection." Significant blood loss is possible: "Patient’s entire blood volume may be lost."

7. Specific Types of Open Wounds:

•Abrasions: "Superficial wound," typically oozing small amounts of blood, may be painful and contaminated. "Don’t try to clean in the prehospital environment."

•Lacerations: "Cut inflicted by a sharp instrument," can be "Clean or jagged incision." Severity depends on depth and damaged structures. "First priority: control bleeding."

•Puncture Wounds: Result from a "Stab wound from a pointed object," "Bullet wound," or an "Impaled foreign object."

•Avulsions: "A flap of skin torn loose (partially or completely)," may have "profuse bleeding." The "Principal danger is loss of blood supply to the avulsed flap." Initial management involves irrigating with normal saline and attempting to place it in anatomical position.

•Amputations: "Complete loss of a body part" due to a "Sharp object" or "Crushing or tearing amputation." Wound edges are often jagged, and "Sharp bone edges may protrude." "Degloving injury" is also mentioned.

•Crush Injuries: Occur when a "Body part [is] crushed between two solid objects," ranging from minor to life-threatening. "Forces may be great enough to rupture internal organs." The longer the compression, the greater the risk of systemic complications. External appearance may not reflect internal damage, and "Muscle deterioration could cause systemic problems."

•Crush Syndrome: Occurs when a body area is trapped for longer than 4 hours, compromising arterial blood flow and causing muscle damage ("Muscles are crushed beyond repair"). "Tissue necrosis" occurs with an influx of electrolytes. Freeing the limb can lead to "Smiling death." "IV access must be established prior to freeing entrapped body part" due to risks of "Renal failure" and "Life-threatening arrhythmias."

•Compartment Syndrome: "Edema and swelling result in increased pressure," compromising circulation, commonly in extremities. It can be "Delayed or nonspecific" initially. Persistence beyond 8 hours is critical. The "Six Ps" (Pain, Paresthesia, Paresis, Pressure, Passive stretch pain, Pulselessness) are key signs.

•Blast Injuries: Have four phases:

◦Primary phase: Due to the "Pressure wave," caused by "air displacement and heat," damaging "air-filled cavities."

◦Secondary phase: Due to "Blast wind" and "Projectiles (flying debris)."

◦Tertiary phase: Due to "Displacement away from the blast site or collapse of the surrounding structure," potentially causing entrapment.

◦Quaternary phase: Miscellaneous events, including "Burns."

8. Scene Safety and Assessment:

•"Safety" is paramount.

•"Evaluate the mechanism of injury." A "High index of suspicion" is needed for significant MOI, considering the forces involved for potential internal damage.

•Determine the number of patients.

•Protect against exposure to body fluids.

•Initial Assessment: Rapidly identify threats to life, including general impression, potential neck/spine injuries, level of consciousness, airway, breathing, circulation, and skin.

•Focused History and Physical Examination: Categorized by MOI. Rapid trauma assessment for significant MOI. For isolated extremity trauma or no significant MOI, address the chief complaint. Follow local protocols. Gather patient history, including events leading to injury, tetanus status, and medications affecting hemostasis.

•Detailed physical examination: More thorough examination en route to identify hidden injuries. "Never delay transport of a patient in critical condition."

•Ongoing assessment (Secondary): Frequent reassessments, vital signs, check interventions, monitor patient, and document all findings.

9. Treatment of Closed Wounds:

•For small contusions, no specific treatment mentioned.

•For extensive closed injuries with potential for significant bleeding and swelling compromising vital structures, use the "ICES mnemonic": "Apply Ice or cold packs," "Apply firm Compression," "Elevate the injured part to a level above the heart," and "Apply a Splint."

10. Treatment of Open Wounds:

•Two general principles: "Control bleeding by whatever method is most effective" and "Keep the wound as clean as possible."

•Determine the magnitude of the injury and assess bleeding (color, amount, origin).

•If bleeding has stopped, the wound is in the healing stage.

11. Bandaging and Dressing Wounds:

•Dressing: Direct application to the wound.

•Bandage: Used to secure the dressing.

•Sterile dressings: Free of microorganisms, used when infection risk is high.

•Nonsterile dressings: Lower infection risk, can be applied over sterile dressings for increased absorption.

•Occlusive dressings: Keep air from passing through, may be sealed on three sides to allow air escape. Most dressings are nonocclusive.

•Adherent dressings: Allow exudate to mesh, removal can be painful and cause bleeding.

•Nonadherent dressings: Allow wound repair products to pass through, applied after closure.

•Dry dressings: Commonly used prehospital.

•Wet dressings: Provide a medium for bacteria (moist dressings used for burns).

•Roller and gauze bandages: Roller bandages are often self-adherent and good for extremities. Gauze bandages are nonadherent.

•Other bandages: Absorbent gauze sponges, elastic bandages, triangular bandages, taping.

•Complications of Improperly Applied Dressings: Risk of further wound contamination. Irrigate open wounds with normal saline, consider antibiotic ointment for small wounds, apply dressing and bandage, clean blood around the site. Hemodynamic complications (continued bleeding, exsanguination) and damage to structural elements (vessels, nerves, etc.) due to excessively tight dressings.

12. Control of External Bleeding:

•Bleeding that can be seen.

•Arterial bleeding: Spurts, bright red blood.

•Venous bleeding: Slow and steady, darker colored blood.

•Capillary bleeding: Slow, even flow, bright or dark red, in minor injuries.

•Direct pressure: The primary method for control.

•Other methods: Elevation, pressure point control, immobilization, and tourniquet (rarely necessary, potential hazards, last resort).

13. Pain Control:

•Cold compress reduces pain and blood flow.

•Entonox PRN (if PCP present).

•Morphine sulfate and other agents (if ACP present).

14. Managing Avulsions and Amputations:

•Managing Avulsions: Irrigate debris, gently fold skin flap back, hold with dry sterile compression dressing.

•Managing Amputations: Stabilize patient, transport patient and part expeditiously, notify ED in advance.

•Preservation of Amputated Parts: Rinse, wrap in sterile dressing, seal in plastic bag, keep cold (on ice pack or cool water bath), do not freeze, warm, place in water, directly on ice, or use dry ice.

15. Managing Impaled Objects:

•"Do not try to remove an impaled object."

•Control hemorrhage with direct compression.

•Do not shorten unless extremely cumbersome.

•Stabilize the object and immobilize the extremity.

•Limit motion of the object.

•Rare exceptions for removal: if it interferes with airway, chest compressions, or if impaled on an immovable object.

16. Managing Wound Healing and Infection:

•Basic measures: keep wound dressed and bandaged.

•Pain control may be needed.

17. Dressing Specific Anatomical Sites:

•Provides guidance on dressings for scalp, face, ear/mastoid, neck, shoulder, trunk, groin/hip, hand/wrist/finger, elbow/knee, and ankle/foot.

18. Crush Syndrome Management:

•"Make every effort to treat the patient before removing the crushing object" due to risks of hypotension and release of harmful products.

•Consider scene safety, initial assessment, potential for renal failure (rhabdomyolysis), hyperkalemia, rapid transport, and ED care.

19. Management of Soft-Tissue Injuries to Specific Anatomical Sites:

•Briefly mentions considerations for face and neck, thorax, and abdomen.

20. Documentation:

•Essential for every patient.

•Include scene findings, patient findings, specific injuries, demographics, and interventions.

Summary:

The document provides a comprehensive overview of soft tissue injuries, starting with the basic structure and function of the skin and progressing through various injury mechanisms, wound healing processes, potential complications, and the assessment and management principles. It emphasizes the importance of scene safety, thorough assessment, controlling bleeding, preventing infection, and appropriate management for specific types of soft tissue injuries like avulsions, amputations, impaled objects, crush injuries, and blast injuries. The document also highlights the significance of proper bandaging and dressing techniques and the need for accurate documentation.