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23 Cards in this Set
- Front
- Back
- 3rd side (hint)
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In the inflammatory phase of wound healing, which 3 cells arrive, in proper order? Which cells are critical to wound healing? |
Cellular response •Neutrophils (24–48 hours): Produce inflammatory products and phagocytosis, not critical to wound healing •Macrophages (48–96 hours): Become dominant cell population (until fibroblast proliferation), most critical to wound healing; orchestrate growth factors •Lymphocytes (5–7 days): Role poorly defined, possible regulation of collagenase and extracellular matrix (ECM) remodeling |
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During the fibroproliferative phase of wound healing (day 4- 3 wks) what is the collagen precursor? |
•Glycosaminoglycan (GAG) production ▸Hyaluronic acid first ▸Then chondroitin-4 sulfate, dermatan sulfate, and heparin sulfate ▸Followed by collagen production (see later) |
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As a wound heals during the maturation phase, which collagen becomes predominant? What is the normal ratio? |
Type I collagen replacement of type III collagen, restoring normal 4:1 ratio |
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When does a wound reach peak tensile strength of 80%? |
Peak tensile strength at approximately 42-60 days–-80% preinjury strength |
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Which vitamin reverses delayed wound healing from steroids? |
Vitamin A: Reverses delayed wound healing from steroids; does not affect immunosuppression.
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How long after wound closure should antineoplastic agents be resumed? |
Few or no adverse effects if administration delayed for 10–14 days after wound closure |
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What is the only recommended topical therapy for scar prevention & when should it be started? |
Scar management •Silicone sheeting recommended as soon as epithelialization is complete and should be continued for at least one month ▸Mechanism of action not known, but suggested mechanisms include increases in temperature and collagenase activity, increased hydration, and polarization of the scar tissue. |
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Negative pressure wound therapy with a sponge dressing is CONTRAINDICATED in which of the following clinical scenarios? A) An abdominal wound with an enteric fistula B) A dorsal hand wound with an exposed tendon C) A lower extremity wound with acute osteomyelitis D) Over a closed surgical incision E) A radiated scalp wound with exposed bone |
The use of negative pressure therapy (NPT) is contraindicated in wounds with active infection including osteomyelitis. Negative pressure dressings in these wounds convert an open, draining wound into a closed wound, which could potentially lead to abscess formation and/or sepsis. NPT has become an integral part of wound management over the past decade and a half. It is a commonly used wound dressing and/or chronic wound management tool. It is instrumental in acute wounds as well (e.g., lower extremity trauma, abdominal wall trauma), and as a skin graft bolster dressing. The major contraindications for its use include wounds with active infection such as untreated osteomyelitis, malignant wounds, wounds with exposed major vessels and/or organs, and wounds with unexplored and/or nonenteric fistulas. |
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Topical treatment for radiation induced dermatitis? |
Steroid cream |
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A 38-year-old unconscious and intoxicated woman is brought to the emergency department after being struck by a motor vehicle. She sustained multiple injuries, including a wound on the right thigh, which measures 12 × 18 cm with areas of exposed fat and muscle. There is dirt and gravel in the wound. Which of the following is the most appropriate next step in management? A) Broad-spectrum antibiotic therapy B) Injection of tetanus toxoid C) Negative pressure wound therapy D) Split-thickness skin grafting E) Wound irrigation and debridement |
In a patient with a grossly dirty wound, it is appropriate to administer a tetanus shot. Tetanus (also known as lockjaw) is characterized by a prolonged contraction of skeletal muscle fibers. The primary symptoms are caused by tetanospasmin, a neurotoxin produced by Clostridium tetani, a gram-positive, rod-shaped, obligate anaerobe. Infection generally occurs through wound contamination and often involves a cut or deep puncture wound. |
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A 30-year-old man is evaluated one year after undergoing vascularized allograft transplantation at the midforearm level. Surveillance angiogram and duplex ultrasound show 60% closure of the ulnar artery and complete occlusion of the radial artery. The patient is adherent to the prescribed immunosuppressive therapy. Clinical evidence of chronic ischemia is suspected. Which of the following underlying processes is most likely in this patient? A) Deposition of preformed immune complex and complement activation B) IgA-mediated response C) IgM and IgG antigen–mediated response D) T-cell–modulated immune response
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The correct response is Option D. Hypersensitivity reactions are divided into four different responses.
Type 1 (allergy) refers to immediate release of IgE, mediated release of histamine, and other vasoactive mediators resulting in manifestation within minutes. Examples include asthma or anaphylaxis. Type 2 (cytotoxic-antibody dependent) refers to binding of IgM or IgG to the target cell, which in this case is a host cell. This results in the membrane attack complex (MAC) destruction of the targeted cell. Examples include thrombocytopenia, Goodpasture, and membranous nephropathy. Type 3 (immune complex–mediated reaction) refers to IgG binding to circulating antigen resulting in formation of an immune complex. These complexes can end up collecting in the vasculature, joints, and kidneys resulting in local destruction. Examples include rheumatoid arthritis, SLE, & serum sickness. Type 4 (delayed type hypersensitivity) refers to the activation of TH1 helper T cells by an antigen-presenting cell. This establishes an immune response memory and when activated again, the TH1 cells activate a macrophage-mediated response resulting in cellular damage. Examples include chronic transplant rejection, contact dermatitis, and multiple sclerosis. |
It's injected. |
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In a patient that developed hyperemia & swelling 4 weeks after face transplant, which type of rejection is most likely? |
The most likely diagnosis is acute rejection, because this patient is still in the early postoperative period when acute rejection is most likely to occur (0 to 3 months). ABO incompatibility and antibody incompatibility would result in hyperacute rejection, which is mediated by the humoral immune system and occurs within minutes of transplantation. Chronic rejection occurs after years and is characterized by vasculopathy and fibrosis. |
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What should be used to treat extravasated concentrated calcium? |
Hyaluronidase is an enzyme that breaks down hyaluronic acid, a mucopolysaccharide that is a normal component of the interstitial fluid barrier. When injected locally within 1 hour of extravasation, it breaks down hyaluronic acid and decreases the viscosity of the extracellular matrix, and facilitates absorption and dispersal of the extravasated chemical. |
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What is the recommended antidote for doxorubicin (anthracycline)? IV treatment? Topical treatment? |
Dexrazoxane has been shown to antagonize the effects of several topoisomerase II poisons such as anthracycline agents, including doxorubicin. Recent clinical trials in Europe have demonstrated its efficacy in minimizing tissue damage from anthracycline extravasation if administered intravenously within 6 hours of extravasation. It is now the recommended initial treatment of anthracycline extravasation, especially in light of its FDA approval in 2007. Dimethyl sulfoxide (DMSO) is a free radical scavenger and an effective solvent. It may also have antibacterial, anti-inflammatory, and vasodilatory properties. Its topical application is effective in preventing ulcerations caused by doxorubicin extravasation. |
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What happens to the ratio of type III to I collagen in keloids? |
Keloid scars demonstrate a decreased ratio of type III to type I collagen. There is more type I collagen in keloids. This is not observed in hypertrophic scars, which have type III. The 2017 exam says: Keloid scars contain excess amounts of type III collagen. In normal skin and scars the ratio of type I collagen to type III collagen is 4:1. In keloids the ratio is decreased due to excess type III collagen deposited by fibroblasts. Hmmm. |
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Scar strength & % reached after: 1 week 2 weeks 3 weeks 4 weeks 6 weeks |
The tensile strength of a skin incision Classic studies by Madden and Peacock showed that a cutaneous wound achieves 5% of its ultimate strength after 1 week, 10% after 2 weeks, 20% after 3 weeks, 40% after 4 weeks, and 80% after 6 weeks. The scar has its full strength 12 weeks after repair |
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What should be used to treat hypertrophic burn scars 12 weeks in? |
Compression decreases blood flow to active scars, leading to decreased production of collagen fibers. This results in a balance of collagen synthesis and lysis that produces a flatter, softer, less vascularized scar. Clinically, burn scar hypertrophy is managed by use of pressure garments and inserts that must be worn almost 24 hours per day. They should be initiated as soon as all burn wounds have closed enough to tolerate wear and continued until the burn scar has matured. Initially, the pressure applied is low (15 to 17 mmHg). Then, as the scar progresses in maturation, custom-made pressure garments that provide 24 to 28 mmHg of pressure may be fabricated for the patient. |
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A 10-year-old girl is referred to the office because of a large, full-thickness cranial defect after sustaining a traumatic injury. Reconstruction with a split cranial bone graft is performed. Which of the following is the most likely mechanism by which the bone graft heals? A) Dural ossification B) Osteoconduction C) Osteogenesis D) Osteoinduction E) Vasculogenesis
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The correct response is Option B. The most likely mechanism of split cranial bone graft healing is osteoconduction. The split cranial bone graft is primarily cortical. After it is separated from its blood supply, it serves as a nonviable scaffold for the ingrowth of blood vessels and osteoprogenitor cells from the recipient site. This process of osteoconduction, or ?creeping substitution,? eventually leads to resorption and replacement of most of the graft with new bone. The graft becomes fully osseointegrated with the recipient site. |
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Osteogenesis is the primary mechanism of bone graft healing for X or Y. |
Osteogenesis is the primary mechanism of bone graft healing for cancellous or vascularized bone grafts. Because these grafts are revascularized rapidly, osteoblasts survive the transplantation and produce new bone at the recipient site. |
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Cut off values for mild, moderate & severe malnutrition, prealbumin & albumin levels? |
Prealbumin 5, 10, 15 Albumin 2.5, 3, 3.5 |
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Which of the following thickens when a tissue expander is placed and inflated? A) Dermis B) Epidermis C) Fat D) Muscle |
B) epidermis |
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NPWT main direct mechanism for wound healing? |
Removal of interstitial fluid leading to increased blood flow |
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Keloid recurrence rates if XRT or steroid injection are used? |
Recurrence rate after excision with radiation therapy was found to be 14%. The recurrence rate after excision with intralesional corticosteroids was 15.4% |
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