All of the following compounds (histamine, kinins, prostaglandin E, fibrin, leukotrienes) are likely contributors to vasodilation during the inflammatory response except
Patient characteristics known to contribute to impaired healing include all of the following except:
- generalized malnutrition
- normovolemic anemia
- old age
The wound shape which most effectively limits wound contraction is a
(Circular wounds contract the least because the forces of contraction cancel each other out to some degree.)
The preferred donor site for a skin graft to be placed on the nose is the
(It is preferable to use skin grafts from the region above the clavicles for wounds on the face because the color matters.)
Flap closure, as opposed to skin grafts, is required for wounds too large for direct wound edge approximation for all of the following tissue types except
Blood vessels denuded of adventitia. They still have a good blood supply and can accept a graft.
Which type of skin graft is most effective in limiting wound contraction
(The percent of dermis included in a graft determines how effectively wound contraction is limited, and it is most effectively limited by full-thickness skin grafts. )
Myofibroblasts are specialized cells differentiated from fibroblasts on electron microscopy because their cytoplasm contains abundant
(Myofibroblasts are differentiated from normal fibroblasts by the microfilaments in their cytoplasm, a multilobulated nucleus, and abundant rough endoplasmic reticulum)
Wound closure with tapes such as Steri Strips has all the following advantages except
- It will not cause any additional marks in the skin
- Inadvertent wound disruption cannot occur
- It is technically simple
- It is comfortable for the patient
- It does not potentiate infection
Inadvertent wound disruption cannot occur.
(Wound closure with tapes such as Steri Strips has many advantages including making no additional marks on the skin, comfort, not potentiating infection and being technically simple to apply. However, the tapes may be removed relatively simply and thereby possibly inadvertently leading to wound disruption.)
The cytokine that is the most potent stimulant of angiogenesis is
Basic fibroblast growth factor (basic FGF).
The most prevalent form of fibrous protein in the dermis is
The following statement(s) is/are true about the reconstructive ladder:
- Negative pressure wound therapy (VAC) may be used to decrease the morbidity of wound closure by simplifying the reconstructive method required.
- More complex procedures carry a higher morbidity risk.
- Tissue expansion may allow for local procedures where inadequate tissue for reconstruction exists.
- Vascularized tissue transfer is more complex and morbid than skin grafting.
Hypertrophic scars stay within the original wound margin and grow vertically. They do not expand horizontally. They are more common in lighter-complexioned individuals and produce a thick, strong scar rich in immature collagen subtypes.
The only bacterial species demonstrated to cause infection in normal individuals in concentrations less than 10^5/g of tissue is which one of the following
Group B streptococcus.
After a scar matures, what percentage of the original skin's tensile strength does the scar possess?
(Depending on a patient's general health, a scar matures by between 6 and 12 months. At this point, it gains between 80% and 85% of its tensile strength. The most rapid increase in tensile strength occurs between 10 and 30 days due to collagen cross-linking.)
Cofactors necessary for successful hydroxylation of proline include all the following except
- Vitamin C.
- Ferrous ion.
Characteristics of the period of scar remodeling include all of the following except:
- Increasing proportion of type I collagen being synthesized relative to type III.
- Increasing numbers of cross-links within collagen molecules.
- Decreasing amounts of water and glycosaminoglycans in matrix.
- Increasing total quantity of collagen in the wound.
- Increasing numbers of cross-links between collagen molecules.
Increasing total quantity of collagen in the wound.
(Scar remodeling is characterized by increases in the numbers of intra and intermolecular cross-links, decreasing amounts of water and glycosaminoglycans in the matrix, and an increase in the relative proportion of type I collagen being synthesized.)
Local factors which invite wound infection include all of the following except:
- Foreign material.
- Radiation injury.
- Poor circulation.
- Disruption of fascia.
Disruption of fascia.
(Depth of injury into the fascia has not been identified as a wound characteristic that predisposes to infection. )
Meshing a skin graft has all of the following advantages except:
- It allows the graft to contour better to irregular surfaces.
- It allows better drainage of serous material.
- It improves the aesthetic appearance of the graft.
- It causes the recipient wound to contract to a greater degree.
- It increases the surface area that can be covered by the graft.
It improves the aesthetic appearance of the graft.
Histamine is primarily produced by the following cell:
Hydroxylation of proline occurs in which cell component?
Rough endoplasmic reticulum.
(Hydroxylation of proline occurs in the rough endoplasmic reticulum after the polypeptide chains that make up the molecule have been synthesized in ribosomes.)
Wound contraction will occur least actively on the
(Wound contraction occurs least actively in areas where the skin is tight such as the pretibial region or the scalp and more actively in the thigh where the skin is looser.)
Epithelialization occurs at maximal speed when a wound is
Covered with an occlusive semipermeable membrane.
(Epithelialization occurs most rapidly when a wound is kept warm and moist as under an occlusive semipermeable membrane.)
Hypoxia in a wound stimulates
Methods to decrease the pain associated with injections of local anesthesia include all of the following except
- Warm the local anesthetic.
- Use the smallest caliber of needle possible.
- Minimize the number of skin punctures.
- Using lower concentration Xylocaine.
- Inject into the subcutaneous tissues as opposed to the dermis.
Using lower concentration Xylocaine.
The classic signs of inflammation
pain, heat, edema, and erythema
(dolor, calor, tumor, rubor)
The following growth factor(s) is/are secreted in the process of wound healing
PDGF, IGF, VEGF, TGF-β.
In partial thickness injuries to the skin, epithelial cells migrate from all of the following except
- Sweat glands.
- Hair follicles.
- Wound edge.
- Blood vessels.
- Sebaceous glands.
Methods to decrease wound infection include all of the following except
- Debridement of all nonviable tissue.
- Removal of all foreign bodies.
- Carefully establish hemostasis before wound closure.
- Careful approximation of multiple layers of subcutaneous fat.
- Pressurized wound irrigation.
Careful approximation of multiple layers of subcutaneous fat.
(Approximation of multiple layers of fat has been associated with an increased infection rate.)
During the first 24 to 48 hours after injury, the predominate leukocyte in wounds is the
Of the following, which wound should not be closed at the time of presentation:
- 3-hour-old human bite to the arm.
- 2-hour-old wound to the thigh of a diabetic.
- 5-hour-old laceration to the hand.
- 6-hour-old dog bite to the neck.
- 8-hour-old wound to the face.
3-hour-old human bite to the arm.
(Even 3-hour-old human bites to the arm should not be closed because of the high level of bacterial contamination present in human saliva.)
Lidocaine with epinephrine should not be used in which one of the following locations
Epinephrine should be avoided in anatomic areas such as the finger where the blood supply is primarily from relatively small axial vessels. Epinephrine can induce vasospasm that can lead to damage to the part.
The amino acid found almost exclusively in collagen is
The predominant type of collagen in dermis is which one of the following
(Type I collagen predominates in dermis whereas type II is the second most common type seen.)
What is the term used to describe the category of wound healing in which a full-thickness wound heals without closing the wound?
Healing by secondary intention.
(Healing by secondary intention describes a nonsurgical approach to wound healing, which allows a wound to close without active surgical technique. Primary and delayed primary healing are surgical techniques. Tissue remodeling occurs in the dermis or neodermis and begins after epidermal healing. Epithelialization occurs to bridge any type of wound closure, but is not specific to nonsurgical closure.)
All of the following processes occur during the intermediate phase of wound healing and predominate between 2 and 4 days after wounding except
- Mesenchymal cell proliferation.
- Mesenchymal cell chemotaxis.
- Glycoprotein synthesis.
(Glycoprotein synthesis occurs synchronously with collagen synthesis and is not one of the intermediate wound healing processes. Intermediate wound healing processes include mesenchymal cell chemotaxis, mesenchymal cell proliferation, angiogenesis, and epithelialization.)
The type of inflammatory cell that does not produce cytokines is which one of the following?
(Neutrophils are the only type of inflammatory cell that does not produce cytokines and is not essential for healing.)
Which of the following is correct regarding split-thickness skin grafts?
Generally change in color after transfer.
Granulation tissue consists mainly of
A mix of small vessels and collagen-rich tissues.
(Granulation tissue is the product of the fibroplastic phase for wound healing (day 2 until day 14) and produces a highly vascular mix of collagen type III fibers. Fibrinous tissue occurs after acute wounding and does not persist beyond the first 3 to 5 days of wounding. MMPs and collagenase are late phase agents that only begin to appear in measurable quantities at 14 days.)
Wound tensile strength is increased by
The adherence of leukocytes to capillary walls in areas of injury and inflammation is mediated by
All of the following increase the likelihood of keloid formation except:
The likelihood of keloid or hypertrophic scars formation is increased in patients between 2 and 40 years, darker skin, wounds in the sternal area and in wounds that cross skin tension lines. Keloids and hypertrophic scars occur rarely in the palms of the hands and the soles of the feet.
Cytokines which are released by one cell and affect a different cell in the same area are functioning in an:
Matrix components found in significant amounts in the extracellular portion of the dermis include all of the following except:
(Triglycerides are predominantly found in the subcutaneous layer and not in the dermis.)
In the secondary healing process of surgical wounds, the major mechanism of wound closure is
Significant collagen synthesis first begins in a wound at
3 to 5 days.
The phase of healing in which the rate of increase in wound breaking strength in incisional wounds is the greatest is:
3 to 6 weeks.
(The time period in which wound breaking strength increases most rapidly is during the 3- to 6- week period when scar remodeling is the predominant wound healing event occurring.)
The best solution to use for topical dressings in most open wounds is
(Normal saline does not damage cells and is well tolerated by wounds. It is an excellent wound irrigant.)
Collagen is synthesized primarily by which one of the following?
The dressing change regimen that will produce maximal debridement is:
Wet-to-dry dressing changes with saline.
(Maximal debridement is accomplished when the dressing is changed utilizing wet-to-dry dressings. Enzymatic agents, such as collagenase, may augment the debriding effect of wet to dry dressing changes.)
The following statements regarding growth factors are true except:
- Epidermal growth factor (EGF) is the most potent stimulant of epithelial cell mitogenesis.
- Vascular endothelial cells produce and proliferate in response to basic fibroblast growth factor (FGF).
- TGF-β is capable of inducing malignant transformation.
- Platelet-derived growth factor (PDGF) stimulates proliferation of fibroblasts.
- In order for growth factors to affect a target cell, the target cell must generally have a specific plasma membrane receptor.
TGF-β is capable of inducing malignant transformation.
(Although it was originally named a transforming factor because TGF-β was thought to induce malignant transformation in cells, it was later shown to be incapable of inducing such a change in cells.)
The time period in which an incisional wound in the skin reaches 80% to 90% of its eventual strength is:
Of the following aspects of the wound healing process, the first to occur is:
Healing of open wounds in patients taking adrenocortical steroids can be improved by topical application of: