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50 Cards in this Set
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Transfusions of blood products can be associated with a number of complications including immediate and delayed hemolytic reactions; nonhemolytic reactions; infectious disease transmission; and complications of massive transfusions. Which of the following statements are true concerning complications of blood transfusions?
a. Immediate hemolytic transfusion reactions are caused by major ABO blood group incompatibility b. Nonhemolytic transfusion reactions are usually due to RH incompatibility and are therefore more common in women of childbearing age c. The most common complication of massive blood transfusion is dilutional thrombocytopenia d. Routine impaired calcium supplementation is necessary during most massive transfusion episodes |
Answer: a, c
Immediate hemolytic reactions are usually caused by blood group ABO incompatibility although they may be caused by antigens of other blood group systems on the transfused red blood cells. The clinical manifestations revolve around the antigen on the red blood cell stroma and the antibody in the patient’s serum, and include production of bradykinin, compliment activation, release of vasoactive agents from platelets, and initiation of systemic clotting. Chills and fevers, chest pain and lumbar pain, tachycardia and hypotension in the conscious patient, and often diffuse bleeding in the anesthetized, unconscious patient constitute this syndrome. Although reaction occurs immediately, death related to the syndrome is uncommon, unless associated with a transfusion of more than 100 ml of blood. Death usually occurs from acute renal failure or hemorrhage due to DIC. Nonhemolytic reactions occur with the frequency of 1 to 2% of all transfusions and consist primarily of chills and fevers during the transfusion or in the first 2 to 3 hours after the transfusion is complete. Mechanism of these reactions includes the presence of antibodies to white blood cell antigens in the transfused blood, especially in the multitransfused or multiparous patient. Massive transfusion complications relate to the rate and volume of blood transfused. The most common complication is dilutional thrombocytopenia. Factor deficiency of the labile factors V and VIII rarely is of sufficient magnitude to result in problems with hemostasis. For hypocalcemia to occur with massive transfusion, citrated blood must be administered, one unit every five minutes. Routine empiric calcium supplementation is unnecessary during most massive transfusion episodes. Conversely, hypothermia is clearly a problem, especially when associated with massive transfusion during complex intraoperative procedures such as thoracoabdominal aneurysm resection. |
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Which of the following statement(s) is/are true concerning the management of a patient with hemophilia A undergoing an elective surgical operation?
a. Concentrates of factor VIII should be given several days prior to elective surgery b. The half-life of factor VIII concentrates is less than 24 hours c. A dose of 40–50 IU/kg of factor VIII concentrate should be given prior to the planned surgical procedure d. Factor VIII concentration administration should be given for the first 24 hours after surgery but may then be stopped if no abnormal bleeding has been observed e. A new recombinant preparation of factor VIII offers the advantage of being virus-free |
Answer: b, c, e
Although the half-life of factor VIII is 2.9 days in normal individuals, the half-life of factor VIII concentrates is 9 to l8 hours. Levels of 80% to 100% of normal should be obtained for surgical bleeding or life-threatening hemorrhage. A dose of 40 to 50 IU/kg of factor VIII should be given with half of this dose then administered every twelve hours. After surgery, transfusion of factor VIII concentrates should be continued for at least ten days. Unfortunately, past use of concentrates of factor VIII obtained from donors has led to a high incidence of HIV infection in the hemophilia population. A new recombinant preparation of factor VIII offers the advantage of being virus-free. |
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The standard management oral anticoagulant therapy for chronic treatment of venous thromboembolism is with the drug warfarin. Which of the following statement(s) is/are true concerning the administration of warfarin?
a. An important complication of warfarin therapy is skin necrosis in patients with protein C deficiency b. Warfarin interferes with vitamin K dependent clotting factors II, VII, IX, X c. For effective anticoagulation the prothrombin time (PT) should be kept at 2 control d. It is recommended that warfarin be continued for at least one year after initial episode of deep venous thrombosis |
Answer: a, b
Warfarin interferes with the vitamin K dependent clotting factors II, VII, IX and X, protein C, and protein S. An important complication of warfarin is skin necrosis with patients both with and without protein C deficiency. This syndrome usually involves full thickness skin slough over fatty areas such as the breasts and buttocks. Warfarin therapy should be monitored using the one stage prothrombin time (PT). The PT should be kept at 1.3 to 1.4 control for effective anticoagulation. At higher levels, there is a five-fold increase in the frequency of bleeding complications. Two major complications of Warfarin therapy include recurrent thrombosis and bleeding. It is recommended that Warfarin be continued four months after an initial episode of deep venous thrombosis. Between ten weeks and four to six months after deep vein thrombosis, there is a recurrent thrombosis rate of 8.3 episodes per 1000 patient months. Between four months and three years, recurrences fall to four episodes per 1000 patient-months. At four months, the risks of bleeding complications matches and exceeds the benefit from anticoagulant therapy and thus is the basis for discontinuing warfarin administration at this time. |
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External pneumatic compression has been advocated for the prevention of deep venous thrombosis during operative procedures. Which of the following statement(s) concerning the use of external pneumatic compression devices is/are true?
a. Intermittent pneumatic compression is as effective as low-dose heparin in prevention of venous thrombosis b. These devices function by compressing the lower extremities therefore augmenting venous return c. Pneumatic compression devices may also exhibit their antithrombotic effect through stimulating local and systemic fibrinolysis d. The length of time that intermittent pneumatic compression should be used includes through the operation and for at least several days in the postoperative period |
Answer: b, c, d
In many well-controlled studies of venous prophylaxis, intermittent pneumatic compression has been found to be as effective as low-dose heparin therapy. In addition to augmentation of venous return with these devices, local and systemic fibrinolysis appears to be stimulated. Fibrinolytic activities are usually reduced for a 7–10 day period after an operation. Studies have demonstrated that the pneumatic-compression devices may exhibit their antithrombotic effect through prevention of this fibrinolytic shutdown even when applied to the upper extremity. The length of time that intermittent pneumatic compression should be used has not been adequately determined but most data suggest that devices should be used through the operation and for at least five days in the face or prolonged immobilization. |
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Von Willebrand’s disease is a common, congenital bleeding disorder. Which of the following statement(s) is/are true concerning Von Willebrand’s disease?
a. As in hemophilia, it is much more common in men b. A history of spontaneous bleeding is common c. Screening laboratory tests will include a prolonged aPTT with a normal prothrombin time d. Pre-treatment for elective surgery require administration of cryoprecipitate to achieve levels of 23–50% of normal |
Answer: c, d
Von Willebrand’s factor is an adhesive protein that mediates platelet adhesion to collagen. In addition, it protects and prevents the rapid removal of factor VIII from blood. The classical deficiency state, Von Willebrand’s disease, is caused by reduction of factor VIII activity (although not as great as Hemophilia A) and the Von Willebrand factor. Clinical manifestations include epistaxis, gingival bleeding, menorrhagia, rare joint or muscle bleeding, and subcutaneous bleeding. Spontaneous bleeding is not as common as in classic Hemophilia A. The syndrome is transmitted as both autosomal dominant (heterozygous) and autosomal recessive disease (homozygous) traits. Therefore there is no sex predilection. Screening laboratory tests include a prolonged aPTT with a normal prothrombin time. In addition, because of the importance of this factor in platelet adhesion, patients display a prolonged bleeding time and have decreased level of factor VIII activity, decreased immunoreactive levels of Von Willebrand’s antigen, and abnormal platelet aggregation responses to ristocetin. The most reliable source of Von Willebrand’s factor is cryoprecipitate. |
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Fibrinolytic therapy is based on activation of plasminogen, the inactive proteolytic enzyme of plasma that binds to fibrin during the formation of thrombosis. Activation of plasminogen to plasmin results in selective thrombolysis at the fibrin clot surface. Which of the following statement(s) is/are true concerning agents used in thrombolytic therapy?
a. Streptokinase is a bacterial protein which is antigenic in humans, resulting in allergic reactions in up to l5% of cases b. Tissue plasminogen activator acts directly on plasmin without an intermediate drug–plasmin complex c. The half-life of urokinase, streptokinase, and TPA all exceed 30 minutes d. Streptokinase is significantly cheaper than urokinase or TPA |
Answer: a, b, d
Streptokinase is a bacterial protein produced by group C b-hemolytic streptococci. It is therefore antigenic in humans and can be associated with allergic reaction in between 2 and 18% of cases. In addition an unusual serum sickness has been reported with streptokinase. Neither urokinase or TPA which is now manufactured with recombinant DNA technology are either associated with allergic side effects or antigenicity. Streptokinase acts through a streptokinase-plasmin complex, whereas urokinase and TPA act directly on plasmin without intermediate drug plasmin complex. The level of the lytic state is greatest with streptokinase, intermediate with urokinase, and least with TPA with the half-lives ranging all less than 1/2 hour in duration. Although the relative efficacy of the three agents has been compared in a number of studies, there appears to be no significant benefit of one agent over the other. Streptokinase however, is markedly less expensive than either urokinase or TPA |
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Which of the following statement(s) is/are true concerning hemophilia A?
a. Hemophilia A is inherited as a sex-linked recessive deficiency of factor VIII b. A positive family history for bleeding disorders present in all patients c. Laboratory tests reveal a prolongation of aPTT, prothrombin time (PT), thrombin clotting time and platelet aggregation d. Spontaneous bleeding is unusual with factor VIII levels greater than 10% of normal |
Answer: a, d
Hemophilia A is inherited as a sex-linked recessive deficiency of factor VIII although 0% of cases are secondary to spontaneous mutation. The incidence of this abnormality is approximately 1/10,000 births. Laboratory screening tests usually reveal a prolongation of an aPTT but normal prothrombin time (PT), thrombin clotting time (TCT) and platelet aggregation testing. The minimum level of VIII required for hemostasis is 30% for minor bleeding, whereas spontaneous bleeding is unusual with factor levels greater than 5 to 10% of normal. In severe genetic deficiency states however, factor levels as low as 1% have been noted and patients are at risk for spontaneous bleeding. |
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Thrombolytic therapy has become a useful adjunct in the management of peripheral arterial occlusion. In this setting, direct intraarterial administration rather than intravenous has been advocated to decrease the risk of systemic bleeding. Which of the following true statement(s) concerning the use of thrombolytic agents for arterial occlusion is/are true?a. A standard technique involves infusing high-dose urokinase, 4000 units per minute for 1–2 hours, directly into the clot by a catheter embedded in the thrombusb. If progress is made, further fibrinolytic therapy is given at 1000 to 2000 units per minute until clot lysis has occurredc. The usual infusion time by the above-stated technique is usually in excess of 24 hoursd. Successful clot lysis occurs more frequently in arterial graft occlusions than native arterial occlusionse. The use of intraoperative thrombolytic therapy may be indicated for situations where complete clot evacuation cannot be accomplished surgically
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Answer: a, b, e The most popular method for intraarterial thrombolytic therapy for arterial occlusion involves passing a guidewire through the thrombus with arteriographic guidance and then infusing high-dose urokinase, 4000 units per minute for 1–2 hours, directly into the clot. If progress is made, further fibrinolytic therapy is given at 1000 to 2000 units per minute for a 6–12 hour period or until clot lysis has occurred. Using this technique, mean infusion time in a recent study was found to be 18 hours and the incidence of bleeding complications was significantly lessened. Selective intraarterial infusion of urokinase was associated with complete clot resolution in 77% of native arterial occlusions versus only 41% with arterial graft occlusion. After thrombolytic therapy has reopened an occluded vessel or graft, radiologic or surgical correction of the lesion responsible for the thrombosis in the first place must be addressed for any hope of long-term success. The use of intraoperative thrombolytic therapy is advocated in those situations where complete clot resolution cannot be accomplished (such as following balloon embolectomy for acute arterial occlusion) or when distal vasculative is occluded and precludes appropriate inflow patency. |
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Tests of coagulation are used to monitor anticoagulation treatment and detect intrinsic abnormalities in coagulation. Which of the following statement(s) is/are true concerning coagulation tests?
a. Prothrombin time (PT) measures both the intrinsic and extrinsic clotting pathways and fibrinogen b. Activated partial thromboplastin time (aPTT) can be used to monitor both oral anticoagulation with Warfarin and intravenous anticoagulation with heparin c. Thrombin clotting time (TCT) is a measurement of the time it takes for exogenously administered thrombin to turn plasma fibrinogen into fibrin clot d. Whole blood activated clotting time (ACT) is a measurement of the ability of whole blood to clot and is used to monitor heparin levels intraoperatively during cardiovascular and peripheral vascular operations |
Answer: a, c, d
Coagulation tests include prothrombin time (PT), which measures the intrinsic and extrinsic pathways of fibrinogen production and is the most common method for measuring a level of oral anticoagulant therapy. The activated partial thromboplastin time (aPTT) identifies the abnormalities of the contact and intrinsic phases of coagulation. Values of aPTT have variably been shown to correlate with heparin dosages and serum heparin levels and are therefore most commonly used in monitoring heparin therapy. It is of no value in long-term management of patients on oral Warfarin therapy. Thrombin clotting time (TCT) is the measure of the time it takes for exogenously administered thrombin to turn plasma fibrinogen into fibrin clot. It is extremely sensitive to levels of heparin and is an excellent measure of measuring the level of heparin-induced anticoagulation. The beauty of the TCT is that it is not specific for any disease condition; thus it may be used to differentiate factor deficiencies from the presence of heparin, or to separate lupus anticoagulant from abnormalities in fibrinogen levels. The whole blood activated clotting time (ACT) is a measurement of the ability of whole blood to clot, and as such, is an available technique for monitoring heparin levels intraoperatively. The ACT responds in a linear fashion to increasing heparin dosage and correlates well with the observed clinical anticoagulation. Adequate anticoagulation for extracorporeal circulation is defined as an ACT of 480 seconds or more while for peripheral vascular applications, values of 250 seconds or greater are considered appropriate. |
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Mini-dose heparin has been shown to be useful in the prophylaxis of postoperative venous thrombosis. Mechanism(s) by which low-dose heparin is/are thought to protect against venous thrombosis include:
a. Enhancement of antithrombin III activity b. A decrease in thrombin availability c. Inhibition of platelet aggregation and subsequent platelet release action d. A mild prolongation of activated partial thromboplastin time |
Answer: a, b, c
Low-dose heparin is thought to protect against venous thrombosis through three different mechanisms. First, antithrombin III activity with its inhibition of activated Factor X is enhanced by only trace amounts of heparin; second, there is a decrease in thrombin availability that prevents its activation and thus its fibrin-stabilizing effect; and third, small doses of heparin may inhibit the second wave of platelet aggregation and subsequent platelet release reaction. The standard doses of heparin administered (5000 units bid) does not affect aPTT. |
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Antithrombin III deficiency is a commonly observed hypercoaguable state. Which of the following statement(s) is/are true concerning this condition?
a. A patient with this deficiency usually presents with thrombosis while on heparin or exhibits an inability to become adequately anticoagulated with heparin b. This deficiency may be either congenital or acquired c. Thrombotic episodes are related to predisposing events such as operations, childbirth, and infections d. Treatment involves acutely the administration of fresh frozen plasma followed by long-term treatment with Coumadin |
Answer: a, b, c, d
Antithrombin III deficiency accounts for about 2% of venous thrombotic event. This deficiency has been described in patients with pulmonary embolism, mesenteric venous thrombosis, lower extremity venous thrombosis, arterial thrombosis, and dialysis fistula failure. Antithrombin III is a serine protease inhibitor of thrombin and factors Xa, IXa and XIa. Because one of the main actions of heparin is to potentiate the anticoagulant effects of antithrombin III, a patient with this deficiency usually presents with thrombosis while on heparin or exhibits the inability to become adequately anticoagulated with heparin. This deficiency may be either congenital (1n2000–5000 births) or acquired. Acquired defects occur with inadequate production, as in liver disease, malignancy, nephrotic syndrome, disseminated intervascular coagulation, malnutrition, or increased protein catabolism. Thrombotic episodes are related to predisposing events such as operations, childbirth, and infections. Once the diagnosis of antithrombin III deficiency is established, fresh frozen plasma should be administered followed by long-term treatment with Coumadin. |
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Which of the following statement(s) is/are true concerning heparin-associated thrombocytopenia?
a. Heparin-associated thrombocytopenia occurs only in the face of over anticoagulation with heparin b. Severe thrombocytopenia (platelet count less than 100,000) is seen in less than 10% of patients treated with heparin c. Heparin-associated thrombocytopenia is due to the aggregation of platelets and may result in thrombosis or embolic episodes d. Heparin-associated thrombocytopenia may be seen within hours of initiation of heparin therapye |
Answer: b, c
Heparin-associated thrombocytopenia occurs in 0.6% to 30% of patients who receive heparin, although severe thrombocytopenia (platelet counts less than 100,000) is seen in fewer than 10% of patients treated with heparin. It is caused by a plasma factor, most likely a heparin-dependent platelet antibody, that causes aggregation of platelets when exposed to heparin. Activation of platelets in this setting results in thrombocytopenia, thrombosis and embolic episodes, which can lead to death. Both bovine and porcine heparin have been associated with this syndrome, which usually begins 5 to 15 days after initiating heparin therapy. Even trivial exposure with heparin such as coating on pulmonary artery catheters or low rate infusion into arterial catheters may cause this syndrom |
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Which of the following statement(s) concerning laboratory studies used in monitoring a patient with intravenous heparinization is/are correct?a. The platelet count should be followed because of the risk of heparin-associated thrombocytopenia
b. The prothrombin time should be observed if prolonged treatment is necessary c. The activated partial thromboplastin time (aPTT) should be maintained at approximately 1.5 times normal d. The serum creatinine should be measured daily to allow adjustments in dose based on renal function |
Answer: a, c
In monitoring the effect of heparin, an activated partial thromboplastin time (aPTT) of 1.5 control or a thrombin clotting time (TCT) of 2 times control reflects adequate anticoagulation. The prothrombin time remains normal. Heparin-associated thrombocytopenia from an immune mechanism is a potential complication of the use of this anticoagulant. Therefore any patient undergoing heparin therapy should have a platelet count determined every other day after the fourth day of therapy or earlier if he or she is known to have been exposed to heparin in the past. Heparin is not excreted through the kidneys or the liver but is cleared through the reticuloendothelial system. Therefore the dose of heparin need not be adjusted in cases of liver or renal dysfunction. |
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Which of the following statement(s) is/are true concerning the vascular response to injury?
a. Vasoconstriction is an early event in the response to injury b. Vasodilatation is a detrimental response to injury with normal body processes working to avoid this process c. Vascular permeability is maintained to prevent further cellular injury d. Histamine, prostaglandin E2 (PGE2) and prostacyclin (PGI2) are important mediators of local vasoconstriction |
Answer: a
After wounding, there is transient vasoconstriction mediated by catecholamines, thromboxane, and prostaglandin F2 (PGF2a). This period of vasoconstriction lasts for only five to ten minutes. Once a clot has been formed and active bleeding has stopped, vasodilatation occurs in an around the wound. Vasodilatation increases local blood flow to the wounded area, supplying the cells and substrate necessary for further wound repair. The vascular endothelial cells also deform, increasing vascular permeability. The vasodilatation and increased endothelial permeability is mediated by histamine, PGE2, and prostacyclin as well as growth factor VEGF (vascular endothelial cell growth factor). These vasodilatory substances are released by injured endothelial cells and mast cells and enhance the egress of cells and substrate into the wound and tissue. |
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Which of the following statement(s) is/are true concerning excessive scarring processes?
a. Keloids occur randomly regardless of gender or race b. Hypertrophic scars and keloid are histologically different c. Keloids tend to develop early and hypertrophic scars late after the surgical injury d. Simple reexcision and closure of a hypertrophic scar can be useful in certain situations such as a wound closed by secondary intention |
Answer: d
True keloids are uncommon and occur predominantly in dark skinned people with a genetic predisposition for keloid formation. In most cases, the gene appears to be transmitted as an autosomal dominant pattern. The primary difference between a keloid and a hypertrophic scar is that a keloid extends beyond the boundary of the original tissue injury. It behaves as a tumor and extends into or invades the normal surrounding tissue creating a scar that is larger than the original wound. Histologically, keloids and hypertrophic scars are similar. Both contain an overabundance of collagen. Although the absolute number of fibroblasts is not increased, the production of collagen continually out paces the activity of collagenase, resulting in a scar of ever increasing dimensions. Hypertrophic scars respect the boundaries of the original injury and do not extend into normal unwounded tissue. There is less of a genetic predisposition, but hypertrophic scars also occur more frequently in Orientals and the Black population. They are often seen on the upper torso and across flexor surfaces. Some improvement in a keloid can be obtained with excision followed by intra-lesional steroid injection. However, the resulting scar is unpredictable and potentially worse. Reexcision and closure should, however, be considered for hypertrophic scars, if the condition of closure can be improved. This is especially pertinent for wounds that originally healed by secondary intention or that are complicated by infection. Keloids typically develop several months after the injury and rarely, if ever, subside. Hypertrophic scars usually develop within the first month after wounding and often subside gradually. |
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Which of the following factors have been demonstrated to promote wound healing in normal individuals?
a. Vitamin A supplementation b. Vitamin C supplementation c. Vitamin E application to the wound d. Zinc supplementation e. None of the above |
Answer: e
Several important systemic factors or conditions influence wound healing. Interestingly, there are no known systemic conditions that lead to enhanced or more rapid wound healing. Overall nutrition as well as adequate vitamins play an important role in wound healing. Vitamin A is involved in the stimulation of fibroplasia, collagen cross-linking, and epithelialization. Although there is no conclusive evidence in humans, vitamin A may be useful clinically for steroid-dependent patients who have problematic wounds or who are undergoing extensive surgical procedures. Vitamin C is a necessary cofactor in hydroxylization of lysine and proline in collagen synthesis and cross-linkage. The utility of vitamin C supplementation in patients who otherwise take in a normal diet has not been established. Vitamin E is applied to wounds and incisions empirically by many patients. The evidence to support this practice is entirely anecdotal. In fact, large doses of vitamin E have been found to inhibit wound healing. Zinc and copper are also important cofactors for many enzyme systems that are important to wound healing. Deficiency states are seen with parenteral nutrition but are rare and readily recognized and treated with supplements. Overall, vitamin and mineral deficiency states are extremely rare in the absence of parenteral nutrition or other extreme dietary restrictions. There is no evidence to support the concept that supranormal provision of these factors enhance wound healing in normal patients. |
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Scar formation is part of the normal healing process following injury. Which of the following tissues has the ability to heal without scar formation?
a. Liver b. Skin c. Bone d. Muscle |
Answer: c
Every tissue in the body undergoes reparative processes after injury. Bone has the unique ability to heal without scar and liver has the potential to regenerate parenchyma, the only organ that has maintained that ability in the adult human. Although liver does regenerate, it often heals with scar (cirrhosis) as well. With these exceptions, all other mature human tissues heal with scar. |
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Reconstitution of the epithelial barrier (epithelialization) begins within hours of the initial injury. Which of the following statement(s) is/are true concerning the process of epithelialization?
a. Bacteria, protein exudate, and necrotic tissue all will compromise this process b. Epithelial cells exhibit contact proliferation c. Epithelialization occurs only from the margins of the wound d. Visible scarring can occur only when the injury extends deeper than the superficial dermis |
Answer: a, d
The initial step of epithelialization involves epithelial cells from the basal layer of the wound edge flattening and migrating across the wound, completing wound coverage within 24–48 hours in a co-opted surgical wound. Epithelial cells exhibit contact inhibition. That is, they will continue to migrate across an appropriate bed until a single continuous layer is formed. Epithelial cell migration occurs by a process in which the epithelial cells send out pseudopods, attaching to the underlying extracellular matrix by integrin receptors. Bacteria, large amounts of protein exudate from leaky capillaries, and necrotic tissue all compromise this process delaying epithelialization. In the case of open wounds, epithelialization results from migration of epithelial cells from remaining dermal appendages, sweat glands, and hair follicles, if the dermis is not completely destroyed. In a full thickness injury, the entire dermis is destroyed or removed. Epithelialization therefore occurs only at the margins of a wound, at a dermal rate of 1–2 mm/day.Visible scarring occurs only when the injury extends deeper than the superficial dermis. Superficial abrasions and burns usually heal without scar, while deeper abrasions and burns may scar significantly. Whenever the dermis is incised, a scar will form. |
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Which of the following statement(s) describe the effects of aging on wound healing?
a. A finer, more cosmetic scar might be expected b. In vitro studies demonstrate decreased proliferative potential of fibroblasts and epithelial cells c. Skin sutures should be left in for a longer period of time d. Wound infection occurs more frequently in elderly patients due to diminished ability to fight infection |
Answer: a, b, c
There are important age-dependent aspects of wound healing. The elderly heal more slowly and with less scarring. There is a gradual attenuation of the inflammatory response with age, and decreased wound healing is one of the consequences. In vitro studies have documented an age-dependent decrease in proliferative potential of fibroblasts and epithelial cells. Clinically this will account for the formation of finer scars and improved cosmetic appearance in the elderly. Sutures should be left in place longer to allow for the slow regain of tensile strength in the aged. This can also be done without concern for formation of suture marks as slower epithelialization occurs along the sutures. There is no evidence to suggest that wound infections occur more commonly in elderly patients. |
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Which of the following statement(s) is/are true concerning pharmacologic agents used to accelerate wound healing?
a. A number of these agents are now currently approved for use in this country b. PDGF (platelet-derived growth factor) promotes fibroblast proliferation, chemotaxis, and collagenase synthesis c. PDGF has been demonstrated in a number of clinical trials to promote healing in chronic wounds d. Growth hormone functions by promoting fibroblast proliferation and collagen synthesis |
Answer: b, c
Currently there are no approved clinical agents that accelerate normal healing. Although a number of clinical trials are in progress, no agents are currently approved. PDGF (platelet-derived growth factor) accelerates wound healing by promoting fibroblast proliferation and chemotaxis and collagenase synthesis. Clinical trials have demonstrated that PDGF has accelerated healing in patients with chronic wounds such as pressure sores and diabetic ulcers. Growth hormone has been successfully used in some situations to reverse the catabolic effect of severe injuries. Wound healing is fundamentally an anabolic event, and in the setting of a severe burn, growth hormone administration significantly accelerates donor site healing, presumably due to its effects in minimizing catabolism. |
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Which of the following statement(s) is/are true concerning the remodeling phase of wound healing?
a. Total collagen content increases steadily through this phase b. The normal adult ratio of collagen is approximately 4:1 of type I to type III collagen. c. Eventually a scar will achieve the strength of unwounded skin d. The proteoglycans are responsible for the ground substance of the extracellular matrix |
Answer: b, d
The transition from the proliferative phase to the remodeling phase of wound healing is defined by reaching collagen equilibrium. Collagen accumulation within the wound becomes maximal by two to three weeks after wounding. Although supramaximal rates of synthesis and degradation continue throughout remodeling, there is no further change in total collagen content. During the initial phase of wound healing, there is a relative abundance of type III collagen in the wound. With remodeling, the normal adult ratio of 4:1 (type I to type III) collagen is restored. The other important component of the extracellular matrix is the ground substance or proteoglycans. These substances are composed of a protein background with long hydrophilic carbohydrate side chains. The hydrophilic nature of these molecules accounts for much of the water content of scar.Scars never achieve the degree of order advanced by collagen in normal skin or tendons, but they do increase in strength for six months or more, eventually reaching 70% of the strength of unwounded skin. |
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There are a multitude of various dressings available. Which of the following statement(s) is/are true concerning options for surgical dressings?
a. Hydrocolloids, such as karaya compounds, offer the primary advantage of increased absorptive ability b. Films, such as Op-site, provide a water impermeable environment to achieve a dry wound c. Impregnates are fine gauze impregnated with a variety of substances such as antibiotics or moisturizing agents that adhere tightly to the wound and do not require a secondary dressing d. Absorptive powders and paste are highly useful in debriding necrotic and fibrous material from wounds and absorbing wound serum |
Answer: a, d
Although the simplest dressing of gauze and tape combined with the use of antibacterial ointment can achieve moist wound healing in most patients. A multitude of other products are available. These can be classified into films, foams, hydrocolloids, hydrogels, and absorptive powders. Films are semipermeable to water, generally made of polyurethane, and are nonabsorptive. They are useful to achieve a moist wound healing environment over a minimally exudative wound such as split thickness skin graft donor sites. The hydrocolloids deserve special mention because they have achieved widespread use. These agents contain hydrophilic materials such as karaya or carboxymethyl cellulose with an adhesive material and are covered by a semipermeable polyurethane film. The material adheres to the skin surrounding the wound, is highly absorptive, and achieves a moist healing environment. Impregnants are generally fine mesh gauze impregnated with either moisturizing, antibacterial, or bactericidal compounds. They are generally not adherent and require a secondary dressing. They do promote reepithelialization and have a antiinfective effect when combined with antibacterial or bactericidal agents. A variety of absorptive powders and pastes are available which consist of starch copolymers or colloidal hydrophilic particles. These agents have high absorbency for tissue wound fluid and debride necrotic and fibrous material from the wound. |
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Which of the following statement(s) is/are true concerning wound contraction?
a. Wound contraction accounts for similar rates of reduction of wound size regardless of their location b. The fibroblast, at the cellular level, is the primary force driving wound contraction c. Excessive wound contraction, when occurring over a joint, may lead to disability d. Actin microfillaments are found in fibroblasts and may play a role in wound contracture |
Answer: b, c, d
Wound contraction is an important event which contrasts healing open wounds and closed incisions. When open wounds contract, the surrounding skin is pulled over the open wound to reduce its size. This can occur much faster than epithelialization. As opposed to other animals, human skin does not have a significant degree of mobility in most sites and specifically on the lower leg, the skin is tightly adherent and less elastic. Therefore, although contraction may account for 90% of reduction of wound size on the perineum, it accounts for, at most, 30–40% of healing of a lower leg ulcer. All healing wounds generate a strong contractile force. When this force is exerted across a joint, it may result in scar contracture which may limit the functional range of motion. At the cellular level, the force which drives wound contraction comes from fibroblasts. Fibroblasts, like muscle cells, contain actin microfilaments. When these filaments increase in number, the cells take a morphologic appearance of myofibroblasts. Myofibroblasts are seen in an increased number in contracting wounds and are felt to play an active role in the process of wound contraction. |
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Which of the following statement(s) is/are true concerning the role of antibiotics in wound care?
a. Systemic antibiotics are indicated for all open wounds b. Bacterial resistance can occur with systemic but not topical antibiotics c. An indication for systemic antibiotic administration is a granulation tissue bacterial count in excess of greater than 105 organisms/gram of tissue on quantitative analysis d. Silver sulfadiazine is useful only for the management of burns |
Answer: c
The role of antibiotics in wound care is controversial. All open wounds are colonized with bacteria. Only when surrounding tissue is invaded (cellulitis) are systemic antibiotics clearly indicated. Antibiotics may also be useful in other situations such as when granulation tissue has a high bacterial count (> 105 organisms/gram tissue), or in the case of reduced resistance to bacteria such as in a diabetic foot ulcer. The routine use of systemic antibiotics for chronic wounds should be avoided to reduce the development of resistant bacterial strains within the wound. Topical ointments are frequently used and can be useful. The topical vehicle may help keep the wound moist and the bacterial count in the wound may be lowered as the result. However, as with most antibiotics, resistant organisms quickly emerge. Silver sulfadiazine, frequently used for burn care, is also useful for chronic wounds. Its broad spectrum of activity, lack of relevant drug-resistant plasmids in bacteria, and its low cost make it a good choice. |
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Which of the following statement(s) is/are true about the role of macrophages in the wound healing process?
a. Macrophages are the dominant cell type during the inflammatory phase of wound healing b. Macrophages are not essential for wound healing c. The macrophage role in wound healing is limited to phagocytosis d. Macrophages are a source of a number of humoral factors essential for wound healing |
Answer: a, d
Within three or four days after injury, macrophages become the dominant cell type in the inflammatory phase of wound healing. The role of macrophages is not limited only to phagocytosis. In addition, macrophages are the source of more than 30 different growth factors and cytokines. These growth factors induce fibroblast proliferation, endothelial cell proliferation (angiogenesis), extracellular matrix production, and recruit and activate additional macrophages. The result is the induction of a wound healing amplification cycle as growth factors recruit macrophages and elicit additional growth factor release. Experimental studies in which antibodies, which either destroy PMNs or block certain aspects of their function, have shown that wounds heal normally, but that healing is significantly impaired without functional macrophages. These studies confirm the dominant role of the macrophage and the inflammatory phase of wound healing. |
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Which of the following statement(s) is/are true concerning the proliferative phase of wound healing?
a. The macrophage is the predominant cell type b. The pink or purple-red appearance of a wound is due to ingrowth and proliferation of endothelial cells c. Collagen, the dominant structural molecule of the wound matrix, contains two unique amino acids, hydroxyproline and hydroxylysine d. The predominant collagen type in a scar is type 3 |
Answer: b, c
The proliferative phase of wound healing begins with the formation of a provisional matrix of fibrin and fibronectin as part of the initial clot formation. Initially, the provisional matrix is populated by macrophages; however, by day three fibroblasts appear in the fibronectin-fibrin framework and initiate collagen synthesis. Fibroblasts proliferate in response to growth factors become the dominant cell type during this phase. Growth factors produced by macrophages simultaneously induce angiogenesis which results in the ingrowth and proliferation of endothelial cells, forming new capillaries. This neovascularity is visible through the epithelium and gives the wound a pink or purple-red appearance.Collagen is the dominant structural molecule in the wound matrix and in the final scar. Collagen is synthesized into an organized cable-like network in a multi-step process with both intra- and intercellular components. The collagen molecule has quantities of two unique amino acids, hydroxyproline and hydroxylysine. The hydroxylization processes which form these amino acids require ascorbic acid (vitamin C) and is necessary for the subsequent stabilization and cross linkage of collagen. The principal collagen type scar is type 1, with lesser amounts of type 3 collagen also present. |
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Which of the following statement(s) is/are correct concerning the management of an open wound?
a. Frequent surgical debridement is usually necessary b. Water irrigation can effectively debride most wounds c. Hydrogen peroxide is particularly useful in the management of open wounds d. A number of the newer dressing products have clearly been shown to promote wound healing compared to simple moist occlusive dressing |
Answer: b
Although there are numerous dressing products commercially available at present, no treatment has been demonstrated to improve healing beyond that of standard treatment which adheres to basic principles. In the absence of large amounts of necrotic tissue, wound debridement does not need to be accomplished surgically. Simple water irrigation either with whirlpool or by water from a hand held shower spray can generate enough power to effectively debride most wounds. Frequent moist dressing changes can accomplish this as well, and in some cases, occlusive absorptive dressings can generate enough tissue proteases to effectively degrade proteins which the absorptive dressings remove. Deeper portions of a wound may accumulate exudate and bacteria. In such cases, water irrigation may be particularly useful. Commonly used agents such as hydrogen peroxide actually may be harmful to normal tissue and are weak oxidants and do a poor job of debriding. Enzymatic debriding agents can be effective when used properly. Most of the newer dressing products have been designed to be more absorptive and achieve moist healing without infection from excess exudate. However, it must be emphasized that as long as moist healing is achieved, there has been no evidence that one product is better than another. |
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Which of the following statement(s) is/are true concerning the clinical management of an open wound?
a. A wet-to-dry dressing is the most optimal form of wound management b. A moist occlusive dressing promotes epithelialization and reduces pain c. The protein rich plasma exudate covering the open wound facilitates healing d. Irrigation of the wound disrupts epithelialization therefore inhibiting the healing process |
Answer: b
Epithelialization is more rapid under moist conditions than dry conditions. Without dressings, a superficial wound, or one with minimal devitalized tissue forms a scab or crust, meaning that the blood and serum will coagulate, dry, and form a protective moisture barrier over the open wound. If a wound is kept moist with an occlusive dressing, then epithelial migration is optimized. In addition, the pain of an open wound is dramatically reduced under an occlusive dressing. The traditional wet-to-dry dressing if truly left to dry, simply produces desiccation and necrosis of the surface layer of the wound which delays epithelialization. Although wet-to-dry dressings can be effective for debridement of wound exudate, they are generally less desirable than a moist healing environment combined with effective cleaning of the wound (i.e. water irrigation). Any open wound will leak plasma. With more inflammation, the plasma capillary permeability is further increased. This exudate of serum proteins and inflammatory cells serves as a rich culture medium. This, in turn, will continue to cycle bacterial proliferation and lead to further exudate formation. The net result of this cycle is delayed or absent wound healing. In addition, the edema that results from capillary dysfunction, increases the distance for diffusion from oxygen and nutrient sources to their metabolic targets. |
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Which of the following surgical techniques lead to improved wound healing?
a. Atraumatic handling of tissue b. Approximation of underlying fatty tissue to obliterate dead space c. Protecting the wound from water for at least one week d. Meticulous hemostasis |
Answer: a, d
There are numerous practical implications for the care of wounds and surgical incisions. Meticulous hemostasis reduces the inflammation of phagocytosis necessary to clear the wound of blood. Atraumatic handling of tissue decreases the load of necrotic or nonviable cells at the wound margin. Deep sutures are best placed only into collagen laden structures that will hold tension, i.e., fascia and dermis. These tissues have a tensile strength to hold sutures under tension. Fat does not contain collagen and will not hold tension. Therefore, fatty tissue should not be sutured as a separate layer. Given that epithelialization of an incision is normally complete within 24–48 hours, there is no reason to protect the incision from water beyond this time period. Allowing the patient to wash or shower one or two days after surgery actually serves useful purpose in debriding the wound. |
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Which of the following cells or blood elements play a role in the initial phases of wound healing?a. Polymorphonuclear leukocytes (PMNs)
b. Platelets c. Monocytes d. Lymphocytes |
Answer: a, b, c, d
Shortly after the initial injury, the wound is full of debris which is cleared over the next several days by recruited and activated phagocytic cells. PMNs begin to arrive immediately, reaching large numbers within 24 hours. The PMNs are followed by macrophages which appear in wounds in significant numbers within two to three days. Macrophages are mononuclear phagocytic cells derived from circulating monocytes or resident tissue macrophages. They complete the process of removing all material not necessary for the ensuing steps of wound healing. Lymphocytes also appear in wounds in small numbers during the inflammatory response. The role of lymphocytes in the wound healing process remains to be clarified, but they are thought to be more related to the chronic inflammatory processes than the initial response to wounding. Platelets are anuclear discoid blood elements derived from bone marrow megakarocytes which play a role in the initial hemostatic process as well as releasing chemotactic factors and factors leading to fibroblast proliferation. |
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A 45-year old male presents with 4 X 4 cm, mobile right solitary thyroid nodule of 5 months duration. The patient is euthyroid. The following statements about his management are true except ? A) Cold nodule on thyroid scan is diagnostic of malignancy B) FNAC is the investigation of choice C) The patient should undergo hemithyroidectomy if FNAC report is inconclusive D) Indirect laryngoscopy should be done in the preoperative period to assess mobility of vocal cords |
A
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A 16-year old boy presents with acute onset pain in the left testis. The following statements about his management are true except ? A) The patient should be prescribed antibiotics and asked to come after a week B) Colour flow Doppler will be very useful in diagnosis C) Scrotal exploration should be done without delay if doppler is not available D) If left testis is not viable on exploration, patient should undergo left Orchidectomy and right orchidopexy |
A
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A person has been brought in casualty with history of road accident. He had lost consciousness transiently and then gained consciousness but again became unconscious. Most likely, he is having brain hemorrhage of ?A) Intracerebral B) Sub arachnoid C) Sub dural D) Extradural |
D
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All of the following are modalities of therapy for hepatocellular carcinoma except ? A) Radiofrequency ablation B) Transarterial catheter embolization C) Percutaneous acetic acid D) Nd Yag laser ablation |
C
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A known HIV positive patient is admitted in an isolation ward after an abdominal surgery following an accident. The resident doctor who changed his dressing the next day found it to be soaked in blood. Which of the following would be the right method of choice of discarding the dressings ? A) Pour 1 % hypochlorite on the dressing material and send it for incineration in a appropriate bag B) Pour 5 % hypochlorite on the dressing material and send it for incineration in a appropriate bag C) Put the dressing material directly in an appropriate bag and send for incineration D) Pour 2 % Lysol on the dressing material and send it for incineration in a appropriate bag |
A
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All of the following can be used to predict severe acute pancreatitis except ? A) Glasgow score >=3 B) APACHE II score >= 9 C) CT severity score >= 6 D) C-reactive protein < 100 |
D
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In treatment of Papillary Carcinoma thyroid, Radioiodine destroys the neoplastic cells predominantly by ? A) X rays B) Beta rays C) Gamma rays D) Alpha particles |
B
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Which of the following carcinoma most frequently metastasizes to brain ? A) Small cell carcinoma lung B) Prostate cancer C) Rectal carcinoma D) Endometrial cancer |
A
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The commonest cyst seen in the Pancreas is ? A) Mucinous cyst B) Pseudo cyst C) Serous cyst D) Malignant cyst |
C
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True about Congenital Pyloric Stenosis is ? A) It is most commonly seen in young adults B) It is due to hypertrophy of pyloric antral circular muscles C) The vomits is bile-stained D) It is managed by resection of the hypertrophied part followed by anastomosis |
B
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Ectopic gastric mucosa is the most commonly responsible for ulcer in ? A) Colon B) Duodenum C) Meckel's diverticulum D) Jejunum |
C
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Which of the following statements is true regarding Meckelâ??s diverticulum ? A) It is present on the mesenteric border B) It is present in 20 % of population C) All the 3 layers are present D) It is treated by Diverticulectomy with Invagination of the stump, as in Appendectomy |
C
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Which of the following is not seen in Chronic Pancreatitis ? A) Hypercalcemia B) Pancreatic Abscess C) Respiratory Insufficiency D) Parenchymal calcification |
A
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Which of the following is not taken into account in Trauma Score ?A) Heart rateB) Blood pressureC) Respiratory rateD) Glasgow coma scale |
C
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Which of the following structures in preserved in Modified Radical Mastectomy ? A) Axillary Nerve B) Lymphatics C) Internal Mammary Artery D) Pectoralis Major |
D
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True statement regarding Warthinâ??s tumor is ? A) It is rare and is most common in submandibular gland B) It is clinically nodular and firm C) It has intensely eosinophilic cytoplasm with double layered columnar cells D) It shows a cold spot on Technetium scan |
C
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Satellite lesions in malignant melanoma are due to ? A) Tumor embolization B) Haematogenous spread C) Lymphatic Permeation D) Perineural spread |
A
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Among the following, the most important prognostic factor in malignant melanoma is ? A) Tumor thickness B) Tumor size C) Irregularity of margins D) Haemorrhage |
A
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A posteriorly perforating ulcer in the pyloric antrum of the stomach is likely to produce initial localized peritonitis or abscess formation in the ? A) Greater sac B) Left subhepatic and hepatorenal spaces (pouch of Morrison) C) Omental bursa D) Right subphrenic space |
C
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The most common facial abnormality seen in Gardener's syndrome is ? A) Ectodermal dysplasia B) Odontomes C) Multiple osteomas D) Dental cysts |
C
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