Flashcards in T2-Burns: Pathophysiology-Local Response Deck (26):
Damage to human skin by heat results in 2 types of injury. What are they?
1. Immediate direct cellular response
2. Delayed response cause by dermal ischemia
When does irreversible cellular damage from protein denaturation occur?
Burns from temps exceeding 113 F (45C)
Edema formation: Vasodilation causes an increase in hydrostatic pressure within the capillaries. The increased hydrostatic pressure combined with the increase in capillary permeabilities causes what?
A loss of water, protein, and electrolytes from the circulating volume into the interstitial spaces
Edema formation: Burn injury does not only cause edema at the site, but ____ & ____ fluid and ____ also enters non burned tissue
Extravasated and sequestered fluid and protein
Edema formation: The directly injured cells have a damaged _____ that leads to an increase in _____ and ____ shift, resulting in cell swelling
Damaged cell membrane
Increase in sodium and potassium
Edema formation: Intracellular water and sodium increase. This process not only occurs in injured cells, but also with those that are not directly heat injured. What develops when the rate of fluid being filtered from micro vessels exceeds that of lymph flow?
Edema formation: What does the amount of edema depend on?
Type and extent of burn injury
Fluid loss: What can happen if fluid is not replaced?
Fluid loss: Normal capillary barriers that separate the intravascular and interstitial compartments are disrupted, which results in what?
Severe depletion of plasma volume AND
Increase in extracellular fluid
Fluid loss: A severe depletion of plasma volume and an increase in extracellular fluid, is clinically manifested as _____
Hypovolemia (shock, renal failure)
Circulatory status: Where do significant circulatory alterations take place?
Zone of stasis located around the dead coagulated tissue
Circulatory status: What do heated red blood cells become?
Circulatory status: Heat damaged cells + hemoconcentration from fluids + depressed CO + tissue edema= ____________.
Reduce the blood flow in the burned area resulting in capillary stasis
Circulatory status: Reducing the blood flow in the burned area results in capillary stasis. What else may develop?
Circulatory status: What happens if thrombi develop after capillary stasis has occurred?
Further impedes circulation and produces tissue ischemia and necrosis
Circulatory status: What substances cause the production of micro emboli, platelet adhesion and aggregation, and increased pain and edema?
Thromboplastic and clot-activating factors from damaged cells
Circulatory status: Circulation in the area around partial thickness wounds ceases _____ after injury but is usually restored within _____.
Ceases immediately, restored in 24-48 hours
Circulatory status: Ful thickness burns, the vascular supply is completely ______, and no appreciable circulation is reestablished until _____ takes place at the interface between burned and unburned skin
Tissue repair: What kind of burns heal spontaneously within 14 days with minimum scarring?
Superficial partial thickness (2nd)
Tissue repair: What burns heal more slowly by regeneration from the epithelial lining of skin appendages, sweat glands, and hair follicles?
A thin, epithelial covering develops in ___ days this type of burn may require several months to heal. Is scarring common?
Deep partial thickness (2nd)
25-35 days; yes
Tissue repair: What can easily convert a partial thickness wound to a full thickness injury, especially in the normally thinner skin of young children?
Infection, trauma, or severe hypothermia
Tissue repair: What burn has cell destruction by coagulation necrosis?
Full thickness burns
Tissue repair: Full thickness burns, dead tissue and exudate convert to a thick, leathery eschar in ____; the eschar liquefies and begins to separate in _____ if not surgically excised. What is this process a result of?
leathery eschar= 48-72 hours
Eschar liquefies= 12-21 days
Process is a result of: autolysis, leukocyte digestion, and disintegration of collagen fibers
Tissue repair: Full thickness burns
What does dead avascular tissue provide?
An ideal environment for bacterial growth
Tissue repair: Full thickness
What happens if tissue is not grafted? What does this mean?
New granulation tissue forms on the wound bed
The wound heals slowly by proliferation from the edges--> HIGH RISK OF INFECTION AND SEVERE SCARRING