Mcq Salad 008

Front 1

A 75–year–old farmer complained of a scaly, plaque like skin lesion on his forearm with recent development of ulceration. Biopsy reveals invasive squamous carcinomas within actinic keratosis negative examination of axillary nodes. Definitive treatment is:

(A)Local wound care until the ulcer heals; then wide excision and repair

(B)Excision of the lesion with frozen section determined free margins and repair

(C) Wide excision; split–thickness skin graft and axillary node dissection

(D) Wide excision; split–thickness graft and radiation therapy

(E) Wide excision; split–thickness graft and chemotherapy 1.

Back 1

(B)

Actinic (solar) keratosis is the most common premalignant lesion usually seen in older, light– complexioned individuals. The incidence of degeneration to invasive squamous carcinoma is 20–25%. These carcinomas, arising from actinic keratosis, metastasize suggesting con– servative excision in treating them.

Front 2

A65–year–old light–complexioned male presents with a solitary scaly plaque like lesion on his forearm present for many years. The lesion is0.5 cm in diameter. Shave biopsy reveals intraep– ithelial squamous cell carcinoma. (Bowen’s dis– ease) incompletely excised. Further treatment includes:

(A)Wide excision of the lesions and sentinel node biopsy

(B) Referral for local radiation therapy

(C)Excision and repair of this area, ensuring clear surgical margins

(D) No further treatment indicated

(E) Local application of 5–fluorouracil(5–FU) cream

Back 2

(C)

Bowen’s disease represents an intraepithe– lial squamous cell carcinoma (carcinoma in situ) and is seen in older patients. These lesions tend to have a long clinical course. Adequate excision is the recommended treatment as these lesions can become invasive squamous cell car– cinomas and metastatasize.

Front 3

A 45–year–old soccer player presents with a 6–month history of an ulcerative nodular lesion, 1.5 cm in diameter in the region of the right oral comunissure. Biospy reveals basal cell carci– noma. The preferred treatment is:

(A) Mohs micrographic surgery and subsequent reconstruction

(B)Excision with a clinical margin and local flap repair31

(C) Topical 5–FU

(D) Local radiation therapy

(E) Cryotherapy

Back 3

(A)

Basal cell carcinoma is the most common malignancy in caucasians. The lesion is cured by complete excision and reconstruction (Moh’s) surgery.

Front 4

A 43–year–old window cleaner fell off a scaffold. He sustained an open wound on the right leg. Debridement was carried out in the emergency department, and the edges of the wound were left open. The wound measures 4 cm × 6 cm. What is TRUE of wound contraction?(A)It occurs within 12 hours of injury.

(B)It is more prominent over the tibia than gluteal region.

(C)It is accelerated if wound is excised 3 days after injury.

(D) It accounts for excessive fibrous tissue formation and fixation of tissue around a joint.(E) It is experimentally less affected by excision of tissue from center of wound rather than at the periphery.

Back 4

(E)

Wound contraction refers to the decrease in diameter of an open wound. It commences on about the fourth day after injury and con– tinues at a relatively rapid rate (1/2–1 mm/d). It is maximal in areas where tissue laxity exists. Wound contraction should not be con– fused with wound contracture where scar for– mation over a joint interferes with mobility. Experimentally, it less affected by excision of tissue from the center of the wound, rather than at the periphery.

Front 5

Which factor is least likely to inhibit wound contraction?

(A) Radiation

(B) Cytolytic drug

(C) Transformation growth factor b

(D) Full–thickness skin graft(E) External splints

Back 5

(D)

Following the application of a full–thickness graft, contraction at the site of the recipient site is maximally inhibited by a full–thickness and to a lesser extent by the partial–thickness graft.

Front 6

A 43–year–old male undergoes a total procto– colectomy for ulcerative colitis. The terminal ileum is brought out on the anterior abdominal wall as an end (Brooks) ileostomy. What is nec– essary to obtain optimal healing?

(A) The ileostomy should be circular rather than square.

(B)The seromuscular layer is sutured to the epithelium of the skin to avoid inflammatory changes.

(C)The ileostomy must be constructed to avoid fixing the mesentery.

(D)The mesentery of the ileal loop should be widely cut to increase its mobility.

(E)The ileostomy must be constructed on the right side.

Back 6

(A)

The ileostomy should be circular rather than square to avoid excessive stenosis of the stoma. Wound healing by a square incision results in a greater degree of stenosis than by an equivalent circular stoma. Failure to close the gap between the ileal loop on the abdominal wall may lead to subsequent internal herniation. It is critical to ensure that the ileal stump is not devascularized.\n

Front 7

A 64–year–old male is to undergo an elective laparo– tomy procedure. The proposed wound is considered as “clean–contaminated.”.This term implies an infection rate of which of the following?

(A) 1%

(B) 2%

(C) 9%

(D) 15%

(E) 30%

Back 7

(C)

In a clean wound, the anticipated infection rate should be 1.5–5%, in a contaminatedwound, 15%, and a dirty wound, 30–40%.

Front 8

A 64–year–old male is to undergo an elective laparo– tomy procedure. The proposed wound is considered as “clean–contaminated.”\nThe wound characteristic indicates which of the following?

(A)Entry of intestinal or urinary tract without significant spillage

(B) Gross spillage from intestinal tract

(C)No entry of intestinal tract

(D) Entry into infected tissue

(E) Drainage of an abscess

Back 8

8.(A) If spillage is substantial or infected tissue has entered, the wound is classified as contam- inated. Dirty wounds are used for drainage of an abscess or debridement of infected tissue.

Front 9

9. A second–degree burn is characterized by which of the following?

(A) Coagulative necrosis extending to subcutaneous fat

(B) Pearly white appearance

(C) Anaesthetic

(D) Erythema and bullae formation

(E) Requires immediate skin grafting

Back 9

9.(D) In a second–degree burn, the skin appen– dages in the dermis are minimally destroyed (superficial partial thickness) or more extensively destroyed (deep partial thickness). In a third– degree(full–thickness) burn, all of the dermis, with skin appendages, are destroyed, and the lesion extends to the subcutaneous fat layer.\n

Front 10

10. The extent of the burn is calculated to represent what percentage of body surface area (Fig. 2–1)?

(A) 10%

(B) 20%\n

(C) 30%

(D) 40%

(E) 50%

Back 10

(D)

In calculating burn surface area, the rule of “9’s” assigns 9% to each upper extremity, 18% to each lower extremity, and 9% to the head and neck. The trunk and abdomen (36%) is divided into four equal parts (9% each). Thus, upper trunk anteriorly would be 9%. //fce-study.netdna-ssl.com/2/images/upload-flashcards/46/51/27/22465127_m.jpeg

Front 11

Perioperative β-adrenergic blockade has been shown to reduce morbidity and mortality in which scenario?

A. 42-year-old man undergoing inguinal hernia repair with hypertension treated with hydrochlorothiazide

B. 28-year-old woman with acute postoperative hypertension after emergency appendectomy

C. 55-year-old man taking metoprolol at home for hypertension now in septic shock after exploratory laparotomy

D. 45-year-old woman taking metoprolol at home for congestive heart failure after laparoscopic cholecystectomy

E. 70-year-old man undergoing colon resection with no known cardiac risk factors

Back 11

Ref.: 7, 8 COMMENTS: Perioperative β-blockers have been shown to reduce morbidity and mortality in select patient groups, including patients undergoing high-risk surgical procedures (vascular, cardiac, thoracic) and those with a Revised Goldman Cardiac Risk Index of greater than 2 (Table 1-1). Now emphasized as a quality measure by the SCIP, β-blockers should not be discontinued in the perioperative period in patients who were taking them preoperatively. Several studies have demonstrated that β-blocker withdrawal is associated with increased 1-year mortality in surgical patients. A N S W E R : D

Front 12

24. Which of the following is true concerning the state of circulating cortisol in a patient with severe sepsis?

A. Cortisol binds to steroid receptors on the cell membrane.

B. Cortisol induces an increase in α- and β-adrenergic receptors on cells.

C. Cortisol exacerbates the inflammatory response.

D. Cortisol decreases the sensitivity of adrenergic receptors to catecholamines.

E. The increase in cortisol level is not proportional to the degree of stress.

Back 12

Ref.: 10 COMMENTS: There is up to a sixfold increase in free cortisol levels in response to the stress of critical illness. Cortisol does indeed induce an increase in adrenergic receptors on cell membranes in an effort to improve hemodynamic stability. It also sensitizes the receptors to catecholamines and suppresses the inflammatory response. Cortisol binds to intracellular steroid receptors, and its increase is proportional to the degree of stress. A N S W E R : B

Front 13

Euthyroid sick syndrome is diagnosed in a patient in the surgical ICU. All of the following are part of this clinical phenomenon except:

A. The patient behaves as though clinically hypothyroid

B. Normal or decreased total serum thyroxine (T4) level

C. Increased serum reversed triiodothyronine (rT3) level

D. Decreased TSH level

E. Decreased total serum T3 level

Back 13

Ref.: 10, 11 COMMENTS: The hallmark of this diagnosis is that the patient behaves neither clinically hypothyroid nor hyperthyroid. The other choices are the expected laboratory findings in patients with this syndrome. Referred to alternatively as euthyroid sick syndrome, low T3 syndrome, low T4 syndrome, and nonthyroidal illness, considerable debate exists regarding whether this syndrome represents a pathologic process or an adaptive response to systemic illness that allows the body to lower its tissue energy requirements. In light of this controversy, no consensus has been reached on how to treat this entity or whether any treatment at all is necessary. Because interpretation of thyroid function tests in critically ill patients is complex, they should therefore not be done in the ICU setting unless a thyroid disorder is strongly suspected. A N S W E R : A

Front 14

Following initial resuscitation, based upon the Parkland formula, the patient was resuscitated with Ringer’s lactate solution at 800 mL/h. Further assessment after 6 hours reveals olig– uria. What should the next step in manage– ment be?

(A) Continue with increased amount of lactated Ringer’s solution

(B) Give Plasma

(C)Give Diuretics to improve urine flow

(D) Colloid solution

(E) Continue initial resuscitation with normal saline

Back 14

(A)

Continue with increased amount of lactated Ringer solution. Urine flow should be 0.5–1.0 mL/kg/h. Patients exposed to inhalation on burns, and those admitted following alcoholic intoxication require additional fluids. In general,\nfor second– and third–degree burns, the Parkland formula is used to administer 4 mL/kg weightof patient × percentage of area of burn. Half of the calculated amount is given within 8 hours and the remainder during the subsequent 16 hours.

Front 15

After a period of resuscitation, management of this patient should include which of the following?

(A) Tangential excision of all eschar until bleeding is encountered

(B) Split–thickness graft (Fig. 2–2) if wound grows b–hemolytic streptococci

(C) Use of cadaver allograft when required

(D) Avoid use of porcine xenograft

(E)Chest x–ray useful for diagnosis of inhalation injury

Back 15

(C)

Use cadaver allograft when required. Tan– gential excision of the skin (to secure a bleeding surface) is done with a guarded dermatome. However, because of possible extensive blood loss, it should be limited to an area <20% of the total body surface area. The presence of bacte– ria growth >105 organisms/cm2 or growth of b–hemolytic streptococci should contraindicate split–skin–thickness grafting.\n

Front 16

A12–year–old boy has multiple skin lesions that are diagnosed as von Recklinghausen’s syn– drome (NF–1). What is TRUE of this condition?

(A)It does not show other malignant lesions.

(B) It is autosomal recessive.

(C)It is associated with optic nerve gliomas.

(D) It is characterized by atrioventricular (AV) malformation.

(E) It is associated with dermoid.

Back 16

(C)

It is inherited as a autosomal dominant dis– order and noted in nearly 1/5000 births. The NF–1 gene encodes a protein neurofibromin that plays a role in neuroectodermal differen– tiation and cardiac development.\n

Front 17

A 29–year–old female swimmer develops a pig– mented lesion on the right thigh. With reference to a pigmented lesion, there is an increased risk of developing melanoma if it is identified with which of the following?

(A) Hutchinson freckle (lentigo maligna)

(B) Freckle involving basal layer of skin

(C) Congenital nevocellular nevi

(D) Hemangioma

(E) Tophi

Back 17

(C)

Most melanoma arise from nondysplastic nevi. Congenital nevocellular nevi found in about 1/100 births have a 3–5% lifetime risk of undergoing malignant change. Dysplastic (a typical) nevi may be familial and predisposed to malignancy. Hutchinson freckle occurs mainly in older patients.\n

Front 18

A 67–year–old business executive and tennis player has a basal cell carcinoma removed from the right cheek. What is TRUE of basal cell car– cinoma (Fig. 2–3)?

(A)It may show a flat ulcer

.(B)It may metastasize to lymph nodes.

(C)It may metastasize to remote skin areas.\n

(D)It is found exclusively in the head and neck.(E)It is best treated by topical 5–FU.

Back 18

(A)

The surface of a basal cell carcinoma has a shiny appearance with telangiectasia. Ulcer for– mation may occur; hence, are named rodent ulcer. Although treatments with 5 FU, cryosurgery, or electrodessication are effective in treatment, sur– gical excision offers the best results and ensures an accurate diagnosis.\n

Front 19

A 38–year–old female undergoes removal of a 2 ×1–cm skin lesion shown to be a melanoma. It is reported as Clark level 1, which implies what?

(A)It is superficial to the basement membrane.(B)It is 1 mm in thickness.

(C) It has nodal involvement.

(D) It involves the papillary layer.

(E) It involves the reticular dermis.

Back 19

(A)

Level II involves papillary layer III between papillar and reticular layer, IV the reticular layer, and V the subcutaneous fat. The Breslow classification utilizes differences in the thick– ness of the tumor.\n

Front 20

A 49–year–old male postman had undergone several operations to excise recurrent infections in both axillary lesions and perianal region. The lesions are hydradenitis supperativa (Fig. 2–4). Which is TRUE of these?(A)They arise from stratum corneum of skin.

(B) They are noninflammatory conditions.\n

(C) They always require surgical intervention.

(D) They frequently involve the scalp.

(E) They are usually caused by staphylococci and streptococci.

Back 20

(E) Usually caused by staphylococci and strep– tococci. Hydradenitis supperativa is an infec– tion of the apocrine glands and surrounding subcutaneous tissue and fascia, which most commonly involves the axilla, groin, perineum, and perianal region. The periumbilical andareola region may be involved. In milder cases, local hygienic measures and tetracycline may be adequate; in more severe cases, wide exci– sion is indicated.\n

Front 21

A 41-year-old woman undergoes complex repair of a deep laceration in her hand. When removing the dressing on postoperative day 2, a large clot with mild surrounding erythema is encountered. Which of the following statements regarding the inflammatory phase of wound healing is true?

A. It lasts up to 24 hours after the injury is incurred.

B. Initial vasodilation is followed by subsequent vasoconstriction.

C. Bradykinin causes vasoconstriction, which inhibits migration of neutrophils to the healing wound.

D. The complement component C5a and platelet factor attract neutrophils to the wound. E. The presence of neutrophils in the wound is essential for normal wound healing.

Back 21

A N S W E R : D

Ref.: 1-5 COMMENTS: The inflammatory phase starts immediately after the injury occurs and lasts up to 72 hours. After the injury, there is a transient period (about 10 minutes) of vasoconstriction followed by active vasodilation. These events are mediated by substances released secondary to the local tissue injury. Vasoactive components such as histamine cause brief periods of vasodilation and increased vascular permeability. The kinins (bradykinin and kallidin) are released by the enzymatic action of kallikrein, which is formed after activation of the coagulation cascade. These components, in addition to those of the complement system, stimulate the release of prostaglandins (particularly PGE1 and PGE2), which work in concert to maintain more prolonged vessel permeability, not only of capillaries but also of larger vessels. In addition, these substances, particularly the complement component C5a and platelet-derived factors such as platelet-derived growth factor (PDGF), act as chemotactic stimuli for neutrophils to enter the wound. Although neutrophils can phagocytize bacteria from a wound, the results of studies involving clean wound healing show that healing can proceed normally without them. Monocytes, however, must be present for normal wound healing because in addition to their role in phagocytosis, they are required to trigger a normal fibroblast response. The later phases of wound healing include the proliferative or regenerative phase and the remodeling phase. The proliferative phase is marked by the appearance of fibroblasts in the wound, which leads to the formation of granulation tissue. The remodeling phase involves an increase in wound strength secondary to collagen remodeling and lasts up to 1 year after the initial injury. The three main phases of wound healing may occur sequentially or simultaneously.

Front 22

A 55-year-old woman with a history of venous stasis ulcers is evaluated for a nonhealing ulcer on the medial aspect of the lower part of her leg. Application of topical ointment to the ulcer and compression stockings have allowed partial healing. However, she states that regardless of the various interventions, the ulcer never completely heals. Which of the following statements regarding wound epithelialization is true?

A. Integrins act as a key modulator of the interaction between epithelial cells and the surrounding environment.

B. Structural support and attachment between the epidermis and dermis are provided by tight cell junctions.

C. Early tensile strength of the wound is a direct result of collagen deposition.

D. A reepithelialized wound develops hair follicles and sweat glands like those seen in normal skin.

E. Contact inhibition can prevent collagen deposition and result in a chronic (nonhealing) wound.

Back 22

A N S W E R : E

Ref.: 2, 4-6 COMMENTS: Migration of epithelial cells is one of the earliest events in wound healing. Shortly after injury and during the inflammatory phase, basal epithelial cells begin to multiply and migrate across the defect, with fibrin strands being used as the support structure. Integrins are the main cellular receptors involved in epithelial migration; they act as sensors and integrators between the extracellular matrix and the epithelial cell cytoskeleton. Tight junctions within the epithelium contribute to its impermeability, whereas the basement membrane contributes to structural support and attachment of the epidermis to the dermis. Surgical incisions seal rather promptly and after 24 hours are protected from the external environment. Early tensile strength is a result of blood vessel ingrowth, epithelialization, and protein aggregation. After covering the wound, the epithelial cells keratinize. The reepithelialized wound has no sweat glands or hair follicles, which distinguishes it from normal skin. Control of the cellular process during wound epithelialization is not completely understood, but it appears to be regulated in part by contact inhibition, with growth being arrested when two or more similar cells come into surface contact. Derangements in the control of this process can result in epidermoid malignancy. Malignancy is more frequently observed in wounds resulting from ionizing radiation or chemical injury, but it can occur in any wound when the healing process has been chronically disrupted. For example, squamous cell carcinoma may develop in patients with chronic burn wounds or osteomyelitis (Marjolin ulcer). A N S W E R : A Wound Healing and Cell Biology Edward F. Hollinger, M.D., Ph.D., and Troy Pittman, M.D. C H A P T E R 2 C H A P T E R 2 / Wound Healing and Cell Biology 11 E. Growth factors are frequently mediated by second messenger systems such as diacylglycerol (DAG) and cyclic adenosine monophosphate (cAMP). Ref.: 7-9 COMMENTS: Cytokines are proteins, glycoproteins, or peptides that bind to target cell surface receptors to stimulate a cellular response. They are important mediators of wound healing. Cytokines can reach target cells by paracrine, autocrine, or intracrine routes. Paracrine mediators are produced by one cell and act on an adjacent target cell. Autocrine mediators are secreted by a cell and act on cell surface receptors on the same cell. Intracrine mediators act within a single cell. Hormones are released by cells and act on a distant target (endocrine route). Although the distinction between cytokines and hormones has blurred, in general, hormones are secreted from specialized glands (e.g., insulin, parathyroid hormone), and cytokines are secreted by a wide variety of cell types. Hormones typically induce body-wide effects, whereas the effects of cytokines may be more localized (e.g., wound healing at the site of an injury). Generally, growth factors are named according to their tissue of origin or their originally discovered action. Growth factors interact with specific membrane receptors to initiate a series of events that ultimately lead to stimulation of cell growth, proliferation, or differentiation. The intermediate events activate a variety of second messenger systems mediated by agents such as inositol 1,4,5-triphosphate (IP3), DAG, and cAMP.

Front 23

A 25-year-old man is seen in the office with complaints of contracture of his left index finger after a burn injury. Which of the following statements is true about growth factors?

A. Epidermal growth factor (EGF) stimulates the production of collagen.

B. Vascular endothelial growth factor (VEGF) and PDGF both stimulate angiogenesis by binding to a common receptor.

C. Fibroblast growth factor (FGF) stimulates wound contraction.

D. Transforming growth factor-β (TGF-β) is stored in endothelial cells.

E. Tumor necrosis factor-α (TNF-α) inhibits angiogenesis.

Back 23

A N S W E R : D

Ref.: 3, 6, 10, 11 COMMENTS: Epidermal growth factor was the first cytokine described. It is a potent mitogen for epithelial cells, endothelial cells, and fibroblasts. EGF stimulates synthesis of fibronectin, angiogenesis, and collagenase activity. Platelet-derived growth factor is released from the alpha granules of platelets and is responsible for the stimulation of neutrophils and macrophages and for increasing production of TGF-β. PDGF is a mitogen and chemotactic agent for fibroblasts and smooth muscle cells and stimulates angiogenesis, collagen synthesis, and collagenase activity. Vascular endothelial growth factor is similar to PDGF but does not bind to the same receptors. VEGF is mitogenic for endothelial cells. Its role in promoting angiogenesis has led to interest in antiVEGF therapies for cancer. Fibroblast growth factor has acidic and basic forms whose actions are identical but whose strengths differ (basic FGF is 10 times stronger than acidic FGF). FGF is mitogenic for endothelial cells, fibroblasts, keratinocytes, and myoblasts; stimulates wound contraction and epithelialization; and induces the production of collagen, fibronectin, and proteoglycans. It is an important mediator of angiogenesis. Transforming growth 3. A 31-year-old man undergoes his second exploratory laparotomy for bowel obstruction secondary to Crohn’s disease. The patient expresses concern regarding the long-term complications related to his midline incision since he has taken steroids for the last year. Which of the following statements regarding the role of collagen in wound healing is true? A. Collagen synthesis in the initial phase of injury is the sole responsibility of endothelial cells. B. Net collagen content increases for up to 2 years after injury. C. At 3 weeks after injury, more than 50% of the tensile strength of the wound has been restored. D. Tensile strength of the wound increases gradually for up to 2 years after injury; however, it generally reaches a level of only about 80% of that of uninjured tissue. E. Tensile strength is the force necessary to reopen a wound. Ref.: 2, 3, 6 COMMENTS: Synthesis of collagen by fibroblasts begins as early as 10 hours after injury and increases rapidly; it peaks by day 6 or 7 and then continues more slowly until day 42. Collagen continues to mature and remodel for years. Its solubility in saline solution and the thermal shrinkage temperature of collagen reflect the intermolecular cross-links, which are directly proportional to collagen age. After 6 weeks, there is no measurable increase in net collagen content. However, synthesis and turnover are ongoing for life. Historical accounts of sailors with scurvy (with impaired collagen production) who experienced reopening of previously healed wounds illustrate this fact. Tensile strength correlates with total collagen content for approximately the first 3 weeks of wound healing. At 3 weeks, the tensile strength of skin is 30% of normal. After this time, there is a much slower increase in the content of collagen until it plateaus at about 6 weeks. Nevertheless, tensile strength continues to increase as a result of intermolecular bonding of collagen and changes in the physical arrangement of collagen fibers. Although the most rapid increase in tensile strength occurs during the first 6 weeks of healing, there is slow gain for at least 2 years. Its ultimate strength, however, never equals that of unwounded tissue, with a level of just 80% of original skin strength being reached. Tensile strength is measured as the load capacity per unit area. It may be differentiated from burst strength, which is the force required to break a wound (independent of its area). For example, in wounds of the face and back, burst strength is different because of differences in skin thickness, even though tensile strength may be similar. Corticosteroids affect wound healing by inhibiting fibroblast proliferation and epithelialization. The latter effect can be reversed by the administration of vitamin A.

Front 24

Which of the following is correct regarding cell signaling?

A. Cytokines are exclusively peptide mediators. B. Autocrine mediators are secreted by a cell and act on adjacent cells of a different type.

C. Cytokines are usually produced by cells specialized for only that purpose.

D. The effects of hormones are generally local rather than global.

Back 24

A N S W E R : C

Steroid injection. If this technique is not successful, excision and radiation treatment can be used. Hypertrophic scars contain an overabundance of collagen, but the dimensions of the scar are confined to the boundaries of the original wound. Hypertrophic scars are often seen in the upper part of the torso and across flexor surfaces. Scar formation is affected by multiple factors, including the patient’s genetic makeup, wound location, age, nutritional status, infection, tension, and surgical technique. In planning surgical incisions, an effort to parallel natural tension lines will promote improved wound healing.

Front 25

A 30-year-old man is scheduled for definitive management of his open wounds after undergoing embolectomy and fasciotomies on his left lower extremity. Which of the following statements is true regarding the use of split- and full-thickness skin grafts?

A. A split-thickness skin graft undergoes approximately 40% shrinkage of its surface area immediately after harvesting.

B. A full-thickness skin graft undergoes approximately 10% shrinkage of its surface area immediately after harvesting.

C. Secondary contraction is more likely to occur after adequate healing of a full-thickness skin graft than after adequate healing of a split-thickness skin graft.

D. Sensation usually returns to areas that have undergone skin grafting.

E. Skin grafts may be exposed to moderate amounts of sunlight without changing pigmentation.

Back 25

Ref.: 2, 3, 6COMMENTS: Skin grafts are considered to be full thickness when they are harvested at the dermal-subcutaneous junction. Splitthickness skin grafts are those that contain epidermis and variable partial thicknesses of underlying dermis. They are usually 0.018 to 0.060 inch in thickness. Cells from epidermal appendages deep to the plane of graft harvest resurface the donor site of a split-thickness skin graft in approximately 1 to 3 weeks, depending on the depth. The donor site requires a moist environment to promote epithelialization, and such an environment is maintained by using polyurethane or hydrocolloid dressings. Because a full-thickness graft removes all epidermal appendages, the defects must be closed primarily. When a skin graft is harvested, there is immediate shrinkage of the surface area of the graft. This process, known as primary contraction, is due to recoil of the elastic fibers of the dermis. The thicker the skin graft, the greater the immediate shrinkage, with full-thickness grafts shrinking by approximately 40% of their initial surface area and split-thickness grafts shrinking by approximately 10% of their initial surface area. Shrinkage must be considered when planning the amount of skin to harvest for covering a given size wound. Secondary contraction occurs when contractile myofibroblasts in the bed of a granulating wound interact with collagen fibers to cause a decrease in the wound’s surface area. Secondary contraction is greater in wounds covered with split-thickness grafts than in those covered with full-thickness grafts. The amount of secondary contracture is inversely proportional to the amount of dermis included in the graft rather than the absolute thickness of the graft. Dermal elements hasten the displacement of myofibroblasts from the wound bed. Sensation may return to areas that have been grafted as long as the bed is suitable and not significantly scarred. Although sensation is not completely normal, it is usually adequate for protection. This process begins at about 10 weeks and is maximal at 2 years. Skin grafts appear to be more sensitive than normal surrounding skin to melanocyte stimulation during exposure to ultraviolet sunlight. Early exposure to sunlight after grafting may lead to permanently increased pigmentation of the graft and should be avoided. Dermabrasion or the application of hydroquinones may be of benefit in reducing this pigmentation. A N S W E R : D

Front 26

A 34-year-old man sustained a gunshot wound to his abdomen that necessitated exploratory laparotomy and small bowel resection. Two weeks after the initial operation, he was reexplored for a large intraabdominal abscess. Which of the following will result in the most rapid gain in strength of the new incision? A. A separate transverse incision is made.

B. The midline scar is excised with a 1-cm margin.

C. The midline incision is reopened without excision of the scar.

D. The midline incision is left to heal by secondary intention.

E. The rate of gain in strength is not affected by the incision technique.

Back 26

A N S W E R : C

Ref.: 2, 3, 6 COMMENTS: When a normally-healing wound is disrupted after approximately the fifth day and then reclosed, return of wound strength is more rapid than with primary healing. This is termed the secondary healing effect and appears to be caused by elimination of the lag phase present in normal primary healing. If the skin edges more than about 7 mm around the initial wound are excised, the resulting incision is through essentially uninjured tissue, so accelerated secondary healing does not occur.

Front 27

A 29-year-old black woman is scheduled for incision and drainage of a breast abscess that has recurred three times despite ultrasound-guided needle drainage. The patient has a history of keloid formation and is concerned about an unsightly scar on her breast. Which of the following statements concerning wound healing is true?

A. Keloids contain an overabundance of fibroblasts.

B. A hypertrophic scar extends beyond the boundaries of the original wound.

C. Improvement is usually seen with keloid excision followed by intralesional steroid injection.

D. An incision placed perpendicular to the lines of natural skin tension will result in the least obvious scar.

E. Hypertrophic scars occur most commonly on the lower extremities.

Back 27

Ref.: 2, 3, 6 COMMENTS: Keloids are caused by an imbalance between collagen production and degradation. The result is a scar that extends beyond the boundaries of the original wound. The absolute number of fibroblasts is not increased. Treatment of keloids is difficult. There is often some improvement with excision and intralesional C H A P T E R 2 / Wound Healing and Cell Biology 13 B. A bacterial count of 1000 organisms per square centimeter retards wound healing. C. Chemotherapy beginning 10 to 14 days after primary wound closure has little effect on the final status of a wound. D. Tissue ischemia is the main component of tissue damage after irradiation. E. Postoperative radiation therapy should be delayed at least 4 to 6 months after surgery to decrease the incidence of wound complications. Ref.: 2-4, 6, 13 COMMENTS: Denervation has no effect on wound contraction or epithelialization. Flap wounds in paraplegics heal satisfactorily when other factors, such as nutrition and temperature, are controlled. Subinfectious bacterial levels appear to accelerate wound healing and the formation of granulation tissue. However, when the level reaches 106 organisms per square centimeter of wound, healing is delayed because of decreased tissue oxygen pressure, increased collagenolysis, and a prolonged inflammatory phase. Various chemotherapeutic agents affect wound healing. Most antimetabolic agents (e.g., 5-fluorouracil) do not delay wound healing, although agents such as doxorubicin have been shown to delay wound healing. When chemotherapy begins 10 to 14 days after wound closure, little effect is noted on its final status despite a demonstrable early retardation in wound strength. Tissue ischemia may not be the primary factor involved in chronic wound-healing problems associated with irradiation. Such problems are most likely related to changes within the nuclei and concomitant cytoplasmic malformation. To decrease wound complications, it is usual to delay surgery until at least 3 to 4 weeks after full-dose irradiation and to avoid radiation therapy for at least 3 to 4 weeks after surgery. A N S W E R : C

Front 28

A 21-year-old graduate student has a large hypertrophic scar on the lower part of her face. The patient had sustained a laceration on her face 2 years previously after hitting her face on the side of a swimming pool. Which of the following statements regarding scar revision is true?

A. Scar maturation refers to the change in size of the wound in the first 1 to 2 months.

B. Scar revision should have been performed in the first 3 months after injury to minimize fibrosis.

C. Revision should be performed earlier in children than in adults.

D. It corrects undesirable pigmentation.

E. Scar revision should be delayed approximately 1 year to allow maturation.

Back 28

Ref.: 2, 3, 6 COMMENTS: Changes in pliability, pigmentation, and configuration of a scar are known as scar maturation. This process continues for many months after an incision, so it is generally recommended that revision not be carried out for approximately 12 to 18 months because natural improvement can be anticipated within this period. In general, scar maturation occurs more rapidly in adults than in children. Most erythematous scars show little improvement after revision, therefore scar revision should not be undertaken for correction of undesirable scar color alone. A N S W E R : E

Front 29

A 45-year-old woman undergoes bilateral transverse rectus abdominis muscle (TRAM) breast reconstruction after modified radical mastectomy. The patient is scheduled for postoperative radiation therapy and is concerned that this will affect her ability to heal her wounds. Which of the following statements regarding wound healing in this patient is true? A. Denervation has a profound effect on wound contraction and epithelialization.

B. A bacterial count of 1000 organisms per square centimeter retards wound healing.

C. Chemotherapy beginning 10 to 14 days after primary wound closure has little effect on the final status of a wound.

D. Tissue ischemia is the main component of tissue damage after irradiation.

E. Postoperative radiation therapy should be delayed at least 4 to 6 months after surgery to decrease the incidence of wound complications.

Back 29

A N S W E R : C

Ref.: 2-4, 6, 13 COMMENTS: Denervation has no effect on wound contraction or epithelialization. Flap wounds in paraplegics heal satisfactorily when other factors, such as nutrition and temperature, are controlled. Subinfectious bacterial levels appear to accelerate wound healing and the formation of granulation tissue. However, when the level reaches 106 organisms per square centimeter of wound, healing is delayed because of decreased tissue oxygen pressure, increased collagenolysis, and a prolonged inflammatory phase. Various chemotherapeutic agents affect wound healing. Most antimetabolic agents (e.g., 5-fluorouracil) do not delay wound healing, although agents such as doxorubicin have been shown to delay wound healing. When chemotherapy begins 10 to 14 days after wound closure, little effect is noted on its final status despite a demonstrable early retardation in wound strength. Tissue ischemia may not be the primary factor involved in chronic wound-healing problems associated with irradiation. Such problems are most likely related to changes within the nuclei and concomitant cytoplasmic malformation. To decrease wound complications, it is usual to delay surgery until at least 3 to 4 weeks after full-dose irradiation and to avoid radiation therapy for at least 3 to 4 weeks after surgery.

Front 30

22. An 18–year–old presents with a well– circumscribed 2–cm mass in her right breast. The mass is painless and has a rubbery consis– tency and discrete borders. It appears to move freely through the breast tissue. What is the likeliest diagnosis?(A) Carcinoma(B) Cyst(C) Fibroadenoma(D) Cystosarcoma phyllodes(E) Intramammary lymph node

Back 30

(C)

Fibroadenomas are most often found in teenage girls. They are firm in consistency, clearly defined , and very mobile. The typical feature on palpation is that they appear to move freely through the breast tissue (“breast mouse”).\n

Front 31

A28–year–old female figure skater presents sev– eral weeks after having sustained an injury to her left breast. She has a painful mass in the upper outer quadrant. Skin retraction is noticed, and a hard mass, 3–4 cm in diameter, can easily be palpated. What is the most likely diagnosis?

(A) Infiltrating carcinoma

(B) Breast abscess

(C) Hematoma

(D) Fat necrosis

(E) Sclerosing adenosis

Back 31

(D)

Fat necrosis is a rare condition that follows injury. Diagnosis may be difficult, and mam– mography and exicision may be necessary to rule out carcinoma. Sclerosing adenosis is a variant of fibrocystic disease and may present\nwith a hard mass. In a hematoma, evidence of resolving ecchymosis may be present.

Front 32

A 35-year-old patient presents to your office with chronic draining subcutaneous periareolar abscesses, which have been incised and drained many times in the past 5 years but keep recur- ring. What is the best treatment of choice?

(A)Repeat incision and drainage (I and D) since the previous procedures were inadequate

(B) Long-term antibiotics

(C) Major duct excision

(D) Complete excision of the drainage tract

(E)Tell the patient there is nothing to do and that this will eventually resolve with age

Back 32

(D)

Mammary fistula also known as Zuska’s disease is felt to represent dilated laciferous ducts, which develop chronic inflammation presenting with these periareolar draining sinuses. They will continue to recur until com- pletely excised, which may require removal of the terminal duct into the nipple, leaving the wound open.

Front 33

Apatient presents 1 month after a benign right breast biopsy with a lateral subcutaneous cord felt just under the skin and causing pain. The etiology of this condition is?

(A) Fat necrosis

(B) Infection

(C) Superficial thrombophlebitis

(D) Suture granuloma

(E) Misdiagnosed breast cancer

Back 33

(C)

This entity is known as Mondor’s disease and is caused by superficial thrombophlebitis usually induced by surgery, infection, or trauma. The process is self–limiting and resolves within 2–10 weeks.\n

Front 34

A 36–year–old woman complains of a 3–month history of bloody discharge from the nipple. At examination, a small nodule is found, deep to the areola. Careful palpation of the nipple– areolar complex results in blood arrearing at the 3 O’clock position. Mammogram findings are normal. What is the likeliest diagnosis?

(A) Intraductal papilloma

(B) Breast cyst

(C) Intraductal carcinoma

(D) Carcinoma in situ

(E) Fat necrosis

Back 34

(A)

Intraductal papilloma is the most common cause of bloody discharge from the nipple. The lesion is treated by excision and is benign in most cases. Cancer is present in 5% of cases. Preoperative ductography can be used to help locate the offending duct .\n

Front 35

A 35–year–old premenopausal woman whose mother had breast cancer comes into your office and has been told that she has fibrocystic breasts. On examination she has multiple areas of thick– ening but no discrete mass. Of the following diagnostic tests, which should be performed?

(A) Re–examination in 6 months

(B) Bilateral breast ultrasound

(C) Thermography

(D) Bilateral breast magnetic resonance imaging (MRI) with gadolinium

(E)Spot compression views if an area of discrete asymmetry or concerning calcifications is seen

Back 35

(D)

Patients who present with fibrocystic mas– topathy at this age should undergo routine screening mammography, either regular film or digital, and ultrasound if no obvious benign etiology is seen on mammography. Spot com– pression mammography is done for any ques– tionable abnormality. Routine use of screening MRI is not indicated at this time.\n

Front 36

During a routine screening mammography, a 62–year–old teacher is informed that she has changes on her mammography, and she should consult her physician. She can be reassured that the findings that indicate a benign condi– tion are which of the following?(A) Discrete, stellate mass

(B) Fine, clustered calcifictions\n

(C) Coarse calcifications

(D) Solid, clearly defined mass with irregular edges

(E) Discrete, nonpalpable mass that has enlarged when compared with a mass shown on a mammogram taken 1 year previously

Back 36

(C)

Coarse calicifications are usually benign. Fine, clustered califications are often milignant and require biopsy. Solid tumors of the breast, especially those that have increased in size or have changed in appearance, are suspicious for carcinoma and require biopsy.\n

Front 37

A40–year–old lawyer comes into your office after seeing some information on the Internet relating to breast cancer. Which of the following factors has not shown to increase a woman’s risk for breast cancer?

(A) Smoking

(B) Previous history of benign breast biopsies

(C) Atypia seen on pathology from previous breast biopsy

(D) First–degree relative with history of breast cancer

(E) Increasing age

Back 37

(A)

Any history of previous breast biopsy, even benign, does show an increase risk of breast cancer. Atypia, family history, and increasing age also increase a woman’s risk. Smoking has not shown an increase risk for breast cancer.\n 31.A 53–year–old waitress inquires about the implica– tions of positive estrogen receptors (ER+) in an inva– sive carcinoma that is excised from her left breast. She should be informed of what?(A)They are more often positive in patients under 50 years of age.(B) If the receptors are positive, antiestrogen therapy is not indicated.(C)If the receptors are positive, the prognosis is more unfavorable.(D) ER and progesterone receptor (PR) status should be determined in all cases of breast carcinoma.(E)ER are usually negative when PR are positive.Questions: 22–34 37

Front 38

Which of the following is not a primary cellular source currently being investigated foruse in tissue repair?

A. Embryonic stem cells

B. Somatic cell nuclear transfer

C. Circulating fetal stem cells

D. Stromal fraction of adult bone marrow and fat

E. Cancer stem cells

Back 38

E

Front 39

Adult mesenchymal stem cells can be characterized by:

A. Their ability to undergo clonal expansion, with the ability to differentiateinto fat, cartilage, and bone under appropriate conditions

B. Their low frequency in fat, but significantly higher frequency and ease of harvest in bonemarrow, with minimal morbidity

C. The disparate growth kinetics and gene transduction capacity between fat and bone marrowsources

D. The inability for bone marrow–derived cells to undergo myogenic differentiation

E. A higher risk for whole blood contamination from fat-derived cells relative to bone marrowsources

Back 39

A

Front 40

Which of the following is not true of fetal stem cells?

A. Fetal stem cells do not proliferate as fast as adult stem cells.

B. Fetal stem cells have been found to possess capacity for adipogenic, osteogenic, andchondrogenic differentiation.

C. Xenogeneic transplantation has shown fetal stem cells to engraft and undergo site-specifictissue differentiation.

D. The use of fetal stem cells is limited by ethical debate and attendant risks associated withintrauterine procedures.

Back 40

A

Front 41

Which of the following is not one of the transcription factors used in cellularreprogramming to create iPS cells?

A. Oct-4

B. Sox-9

C. Klf-4

D. Nanog

Back 41

D

Front 42

Which of the following is not true of ASCs?

A. ASCs can be differentiated into bone, fat, and cartilage.

B. The major advantage of ASCs is their relative abundance and ease ofisolation from subcutaneous adipose tissue through standard lipoaspiratetechniques.

C. ASCs represent a homogeneous cell line derived from lipoaspirate cells.

D. None of the above

Back 42

C

Front 43

6. Which of the following cell types is not pluripotent?

A. ESCs

B. iPS cells

C. ASCs

D. Cells derived by somatic cell nuclear transfer (SCNTs)

Back 43

C

Front 44

7. Induced pluripotent stem cells are characterized by:

A. Requirement for viral integration of defined transcription factors to dedifferentiate intopluripotent state

B. Cells that are identical to embryonic stem cells

C. Cells that give rise to teratoma comprising all three germ layers wheninjected into immunodeficient mouse

D. Inability to differentiate into neurons

Back 44

C

Front 45

In the skin, epidermal stem cells reside in:

A. Sweat glands

B. Bulge region along hair follicles

C. Superficial epidermis

D. Subcutaneous fat

Back 45

B

Front 46

A 53–year–old waitress inquires about the implica– tions of positive estrogen receptors (ER+) in an inva– sive carcinoma that is excised from her left breast.

The patient is postmenopausal. She should be informed that which of the following hormonal therapy has been shown to be most effective?(A) Tamoxifen

(B) Raloxifene

(C) Toremifene

(D) Megace

(E) Aromotase inhibitors

Back 46

(E)

Recent studies are showing aromatase inhibitors to be more beneficial than tamoxifen in preventing breast cancer recurrence in post– menopausal women. Tamoxifen, raloxifene, and toremifene are all selective ER modulators (SERMS), which act by competitively blocking estrogen binding sites and thus reducing esto– gen stimulation of breast tissue. Megace (mege– strol acetate) has been used for metastatic breast cancer.

Front 47

Strategies that have been suggested to decrease the risk for postoperative pulmonary complications include all of the following except:

A. Routine nasogastric tube decompression

B. Lung expansion maneuvers

C. Preoperative smoking cessation

D. Postoperative epidural anesthesia

E. Use of intraoperative short-acting neuromuscular blocking agents

Back 47

Ref.: 9 COMMENTS: Postoperative pulmonary complications include atelectasis, pneumonia, prolonged mechanical ventilation, bronchospasm, and exacerbation of underlying lung disease. Aggressive pulmonary toilet, smoking cessation, epidural analgesia, and minimal neuromuscular blockade have indeed been shown to be effective means of reducing postoperative respiratory complications. In contrast, because systemic reviews have found that routine use of nasogastric decompression increases pulmonary complications, nasogastric tubes should be used postoperatively only when specifically indicated for the operative procedure. An early postoperative fever is most likely due to atelectasis causing a respiratory shunt secondary to alveolar collapse. This results in varying degrees of hypoxemia. Persistent collapse leaves alveoli prone to bacterial colonization. Aggressive pulmonary toilet with incentive spirometry, forced coughing, and frequent turning is the best prevention. A N S W E R : A

Front 48

All of the following are true concerning the sympathetic nervous system except:

A. Circulating epinephrine is produced mainly in the adrenal gland and secreted as a hormone.

B. Most circulating norepinephrine is derived from synaptic nerve clefts.

C. Activation of the sympathetic nervous system results in vasoconstriction, tachycardia, and tachypnea.

D. Norepinephrine acts primarily as a neurotransmitter.

E. Up to 5% of norepinephrine and 15% of dopamine are produced by the enteric nervous system.

Back 48

A N S W E R : E

Ref.: 10 COMMENTS: Secretion of catecholamines by the sympathetic nervous system is classically known as the “fight or flight” response. The first four choices represent the classic pathways of TABLE 1-1 Cardiac Risk Indices Variables Points Comments Goldman Cardiac Risk Index, 1977 1. Third heart sound or jugular venous distention 11 0-5 points = 1%* 6-12 points = 7% 13-25 points = 14% >26 points = 78% 2. Recent myocardial infarction 10 3. Non–sinus rhythm or premature atrial contraction on ECG 7 4. >5 premature ventricular contractions 7 5. Age >70 years 5 6. Emergency operation 4 7. Poor general medical condition 3 8. Intrathoracic, intraperitoneal, or aortic surgery 3 9. Important valvular aortic stenosis 3 Revised Cardiac Risk Index 1. Ischemic heart disease 1 Each increment in points increases the risk for postoperative myocardial morbidity 2. Congestive heart failure 1 3. Cerebral vascular disease 1 4. High-risk surgery 1 5. Preoperative treatment of diabetes with insulin 1 6. Preoperative creatinine >2 mg/dL 1 ECG, Electrocardiography. *Cardiac complication rate. C H A P T E R 1 / Physiologic Response to Injury 9 the sympathetic response. The enteric organs have actually been found to produce up to 37% of norepinephrine and greater than 50% of the dopamine found in the body.

Front 49

18. List the layers of skin from the most superficial to the deepest layer adjacent to the dermis

(a) basal layer, (b) granular layer, (c) prickle layer, and (d) stratum corneum.

(A)a b c d

(B)d b a c

(C)d c b a

(D)c a b d

(E)c a d b

Back 49

(C)

The stratum corneum consists mainly of dead cells and keratin.

Front 50

19. A12–year–old boy has multiple skin lesions that are diagnosed as von Recklinghausen’s syn– drome (NF 1). What is TRUE of this condition?

(A)It does not show other malignant lesions.

(B) It is autosomal recessive.

(C)It is associated with optic nerve gliomas.

(D) It is characterized by AV malformation.

(E) It is assocated with dermoid.

Back 50

19.(C) It is inherited as a autosomal dominant dis– order and noted in nearly 1/5,000 births. The NF–1 gene encodes a protein neurofibromin that plays a role in neuroectodermal differen– tiation and cardiac development.\n