Soft Tissue Trauma Flashcards
what % of total body weight does the skin make up?
15% of total body weight
what does the skin keep out and what does the skin keep in the body?
Keeps invading pathogens out while containing body substances and fluids
Key organ of sensation, radiates excess body heat, and conserves heat in cold conditions
Durable, pliable, and accommodating tissue
what is the first tissue to experience effects of trauma?
skin, highly capable of self-repair
what is the integumentary system?
INTEGUMENTARY SYSTEM – skin, consisting of epidermis, dermis, and subcutaneous layers
what may trauma present itself as for the skin?
Open injuries – abrasions, lacerations, incisions, punctures, avulsions, and amputations
Pathway for infections
Closed injuries – contusions, hematomas, and crush injuries
Uncontrolled blood loss = hypovolemia/shock
May seriously affect health – severe blood/fluid loss, infection, and hypothermia
what is the most common type of trauma?
Soft tissue injuries are the most common type of trauma
Risk factors include age (school-age children and the elderly), alcohol or drug abuse, or certain occupations
what is a hemorrhage?
Blood loss ranges from minor to life-threatening
May be arterial (bright red; spurting/pulsing), venous (dark red; flowing), or capillary (red; oozing) – bleeding
could be from any combination
Typically easy to control with direct pressure; may require surgical repair or sutures
Important to determine approximate amount of blood loss – determines treatment plan
what is the difference between a clean cut and a jagged cut?
Type of injury is typically more important than which vessel is involved
“clean cut” lacerations or amputations cause smooth muscle in vessel walls to constrict and decrease lumen size, assisting in
blood loss and initiating clotting
Jagged cuts cause vessels expansion with every muscle contraction, increasing blood loss if not controlled by pressure
what is wound healing? when does it begin? what are the stages?
Begins immediately following injury and may take months to fully repair; important in management of homeostatis
Stages of healing – hemostasis, inflammation, epithelialization, neovascularization, collagen synthesis (may overlap
with each other)
what is hemostasis?
Body’s natural ability to stop bleeding; the ability to clot blood
Begins almost immediately following injury
Muscular layers begin constricting; longitudinal muscles pull cut ends into the contracted muscle to reduce loss
Capillaries do not contain that muscular layer and will continue to bleed on their own
Platelets begin clotting process – vessel walls and platelets themselves become “sticky” in turbulent blood flow
Platelets sticking to vessels and themselves causes an initial “clot” or “platelet plug” that is unstable
When the tunica intima is disrupted, collagen (and other structural proteins), are exposed to blood
A complex series of enzyme reactions change certain blood proteins to fibrin strands
Strands entrap RBCs and produce a gelatinous mass that binds with platelets to further occlude the bleeding vessel =
COAGULATION
Over time, the clot shrinks and contracts, pulling wound edges closer
When the clot is no longer needed, the body reabsorbs it and the superficial scab drops away naturally
what is inflammation?
Complex process of local cellular and biochemical changes as a consequence of injury or infection; an early stage of healing
Beings shortly after hemostasis sets in
Involves WBCs, proteins involved in immunity, and hormone-like chemicals that signal cell to mobilize
Chemotactic factors = chemicals released by WBCs that attract more WBCs to an area of inflammation
Recruit cells responsible for consuming cellular debris, invading bacteria, or other foreign or damaged cells
PHAGOCYTES
Granulocytes = WBCs charged with the primary purpose of neutralizing foreign bacteria
Macrophages = immune system cells that have the ability to recognize and ingest foreign pathogens
PHAGOCYTOSIS = process in which a cell surrounds and absorbs a bacterium or other particle
Lymphocytes and immunoglobins are released to attack invading pathogens directly
Begin the inflammatory process
Histamine is released by mast cells based on all the above-mentioned responses
Dilates precapillary vessels, increases capillary permeability and blood flow (increased oxygenation) to injured site
This is what produces the swollen, red, and warm appearance/condition at an injury site
The result is to clear away dead/dying tissue, remove bacteria, and prepares damaged area for rebuilding
what is epitheliazation?
Early stage of wound healing in which epithelial cells migrate over the surface of the wound
Stratum germinativum divide and regenerate rapidly to provide a uniform layer of skin cells along healing site
May begin as early as 48hrs with very clean wounds
Thinner, different pigmentation, and lacking hair follicles in comparison to regular skin
Typically functional and cosmetically similar, but not exact
Larger wounds cause new layer to be incomplete and allow the “scar” (pinkish colour) of collagen to show through
what is neovascularization?
New growth of capillaries in response to healing; come from surrounding, undamaged capillaries and spreads into wound
More fragile and may bleed easily; takes months for them to strengthen enough for wound to protect the new vessels properly
Healing requires well-oxygenated, nutrient-rich blood supply – which initiates this stage
what is collagen synthesis?
Collagen = tough, strong protein that makes up most of the body’s connective tissue (in hair and bones, as well)
Main structural protein
Fibroblasts = specialized cells that form collagen when brought to the wound site
Continue to work to strength scar and tissue even after scab falls off
Collagen causes wound to be bound together, however is only 60% as strong and elastic as undamaged tissue
even after scar development (typically 4 months after scarring occurs)
This is why scars may reopen if aggravated
Remodelling = stage in the wound healing process in which collagen is broken down and re-laid in an orderly
fashion
May take 6-12 months to complete; final appearance of injury site may not be determined until this time
what is a closed wound?
doesnt break skin
what is a contusion?
Injuries that crush and damage small blood vessels
Blood is drawn into inflamed tissue, causing erythema (general reddening of skin due to dilation of the superficial
capillaries)
Blood leaks into surrounding interstitial spaces through damaged vessels
Hemoglobin in free blood loses oxygen, becomes dark red and then blue, resulting in ecchymosis (blue-black
discoloration of the skin; typical “bruising”) – may not be evident in prehospital care
More pronounced in areas where the blunt force mechanism and skeletal structure trap skin
Example = steering wheel and ribs/sternum
what is a hematoma?
Collection of blood beneath the skin or trapped within a body compartment
Blood can actually separate tissue and pool in a pocket
Very visible in areas directly above a solid bone structure (head injuries, for example)
Less pronounced in areas of the body with large “free” space/body cavities
Severe hematomas may contribute significantly to hypovolemia
Example = the thigh – can contain more than a litre of blood before swelling becomes noticeable
what is a crush injury?
Mechanism of injury in which tissue is locally compressed by high pressure forces
CRUSH SYNDROME = systemic disorder of severe metabolic disturbances resulting from the crush of a limb or
other body part
Considered a life-threatening event
If pressure remains in place for several hours, destruction of skeletal muscle cells leads to accumulation of large
quantities of myoglobin (cell protein), potassium, lactic and uric acids, and other toxins
When pressure is released, these built up toxins enter the bloodstream causing severe metabolic acidosis
Which is toxic to the heart and kidneys
what is an abrasion?
Scraping or abrading away of the superficial layers of the skin; epidermis and upper layer of dermis
Bleeding is usually limited – involving only superficial capillaries
If it involves a larger area of epidermis, may carry the danger of serious infection
what is an incision?
Very smooth or surgical lacerations, frequently caused by a knife, scalpel, razor blade, or piece of glass
Bleeds freely, but heals well with proper care
what is a laceration?
Open wound, normally a tear with jagged borders
Penetrates more deeply into the dermis layer, but typically involves a smaller surface area, limiting the injury to the tissue
immediately involved in the trauma
Endangers arteries, arterioles, veins, venules, nerves, muscles, tendons, ligaments, and perhaps organs in the area
Provides a pathway for infection greater than that of an abrasion
Cutting across the tension lines – wound pulls apart, spreads widely, or gapes
Cutting parallel to the tension lines – gape/spread very little (easily repaired)
Tension lines can be either static or dynamic
Static – areas with limited movement of the tissue and structures beneath (as in skin over abdomen)
Dynamic – areas subject to great movement (as in skin over joints)
Increased motion complicates skin repair
what is a puncture?
Deep, narrow wound to the skin and underlying organs that carries an increased danger of infection
External signs of injury may close and conceal the extent of the internal damage
If the puncture is deep enough, many structures may be involved
Infection is not only caused by the opening of the skin to the external environment, but also by the foreign object
carrying bacteria into the body – internal, deoxygenated area is warm and moist = colonization of bacteria
what is an impaled object?
IMPAILED OBJECTS (not a wound themselves, but associated with lacerations and punctures)
Most critical to consider the damage caused if object is prematurely removed
Object may become entangled in underlying arteries, nerves, and structures, resulting in significantly increased damage if
removed
May be “corking” an underlying great vessel hemorrhage temporarily if left in place
Especially important to consider when object is impaled in the neck or trunk – many important vessels and also difficult to apply enough
direct pressure
what is an avulsion?
Forceful tearing away or separation of body tissue; may be considered partial or complete
Frequently seen with blunt trauma to skull, animal bites, or machinery accidents
Severity depends on the area and surface area involved, the compromise of circulation, and degree of
contamination
what is a degloving injury?
DEGLOVING INJURY = avulsion in which the mechanism of injury tears the skin off the underlying muscle,
tissue, blood vessels, and bone
Seen most frequently in farming and industrial setting, and also with watches and rings
Poor prognosis for use of digit or extremity unless vasculatures is not completely damaged
Essentially, the object (like a ring or a watch) or the skin around the extremity gets caught and is pulled the opposite
direction as the weight of the patient or machinery
Literally the same mechanism as removing a glove or a sock where you take the wrist/ankle band and turn it inside-out as it is being removed
what is amputation?
Severance, removal, or detachment, either partial or complete, of a body part
Typically results in complete loss of limb or digit
May have limited hemorrhage as the vessel ends spasm and contract back into surround muscle tissue
Surgical repair may include reattaching the detached part – including surgical repair of blood vessels, or may
involve using the skin from the detached part to graft the end of the remaining limb/digit
If skin is too tight or unavailable, the surgeon may be required to further cut back the bone and muscle to allow extra skin
to close over the damaged end
Often times surgical reattachment is only possible with clean severing of the limb/digit
May result in permanently shortened limb/digit, decreasing mobility and function
