Which of the following statement(s) is/are true concerning tumor necrosis factor (TNF)? a. TNF is a product of activated macrophages secreted in response to contact with endotoxin or lipopolysaccharide, antibody complexes, or inflammatory stimuli b. The liver and gut appear to be a major source of TNF following hypoperfusion c. Circulating levels of TNF correlate well with severity of tissue injury in shock d. Recently completed clinical trials of anti-TNF antibody in septic patients shows a marked improvement in survival

Which of the following statement(s) is/are true concerning tumor necrosis factor (TNF)? a. TNF is a product of activated macrophages secreted in response to contact with endotoxin or lipopolysaccharide, antibody complexes, or inflammatory stimuli b. The liver and gut appear to be a major source of TNF following hypoperfusion c. Circulating levels of TNF correlate well with severity of tissue injury in shock d. Recently completed clinical trials of anti-TNF antibody in septic patients shows a marked improvement in survival
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Answer: a, b  Tumor necrosis factor (TNF), a protein product of activated macrophages, is secreted in response to contact with endotoxin or lipopolysaccharide, antibody complexes, or other inflammatory stimuli. Elevation of serum levels of TNF have been reported shortly after experimental trauma and shock, however, documentation of elevated circulating levels of TNF in human shock is less clear. Furthermore, circulating levels of TNF cannot be correlated with severity of tissue injury or shock. This variability is thought to be due to rapid clearance and uptake by membrane receptors and by soluble membrane receptors that are released from multiple cells following stress and injury. Following hypoperfusion the liver and gut appear to be the major source of TNF that is rapidly cleared but responsible for inducing hepatocyte changes following shock. The release of breakdown products and escape of bacterial and endotoxin through the damaged mucosal barrier of the gut following shock allows or induces activation of tissue-fixed macrophage (Kupffer cell) of the liver which then produces secondary inflammatory mediators contributing to the post-resuscitation clinical response and inflammatory mediator activation seen in the systemic inflammatory response syndrome. TNF is central to inflammatory response, particularly in sepsis and following endotoxemia or bacteremia. TNF also induces secondary inflammatory responses through direct interaction with specific membrane receptors, TNF-r. Treatment with anti-TNF antibody in the experimental setting protects animals from the deleterious effects of lethal bacteremia and endotoxemia. However, recently completed clinical trials in septic patients utilizing infusion of monoclonal antibodies to the TNF molecule have shown no overall survival benefit
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The use of antibiotics can be based on either the clinical course of a patient without the benefit of well-defined microbiologic data (empiric therapy), or targeted at specific identified pathogens once sensitivity reports are available (directed therapy). The following statement(s) is/are true concerning these therapies. a. The issue of toxic side effects of antibiotics is only important in dealing with emperic therapy b. Single agent therapy is generally inferior to specific multi-drug therapy (aminoglycoside plus an antianaerobic agent) for the treatment of secondary bacterial peritonitis due to appendicitis, diverticulitis, penetrating gastrointestinal injury, or anastomotic leak c. With the empiric use of antibiotics, a diligent search for the septic source should be undertaken and co

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Sepsis causes a marked metabolic response. Which of the following statement(s) is/are true concerning the metabolic response to sepsis? a. Oxygen consumption is increased in the face of infection b. In a patient with a maximal metabolic rate secondary to trauma, the presence of infection will increase the rate further c. Metabolic rate increases at a rate of approximately 10% for each increase of 1°C in central temperature d. The extent of increase in oxygen consumption relates to the severity of the infection

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The neurohormonal arm of the stress response is well defined. Less is known about the inflammatory arm mediated primarily by cytokines. Which of the following statement(s) is/are true concerning this arm of the surgical stress response? a. Cytokines primarily work locally via direct cell-to-cell communication b. Cytokines are never detectable in the systemic bloodstream c. Cytokines are produced only by immune cells attracted to the site of injury d. Cytokine release may stimulate the release of other cytokines leading to an important cascade of events

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New treatment modalities designed to modulate host defense mechanisms that have been demonstrated conclusively to be of benefit include: a. Gut decontamination b. Anti-LPS antibody c. Anti-TNF antibody d. Thymopentin e. None of the above

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Which of the following statement(s) is/are true concerning the multiorgan failure syndrome (MOFS)? a. Changes in the splanchnic and pulmonary microcirculation are critical to the development of MOFS b. Tissue fixed microphages, including the liver Kupffer cell, have little role in the development of MOFS c. MOFS represents systemic consequences of loss of homeostatic control of local inflammation and microcirculatory hypoperfusion d. The nature of MOFS is highly dependent upon the etiology of the underlying problem

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Which of the following statement(s) is/are true concerning the outcome in patients with acute renal failure? a. Mortality for ischemic acute tubular necrosis without other organ failure is approximately 6% b. Multiple organ failure complicated with acute renal failure is associated with mortality ranging from 50% to 90% c. Recovery of renal function after six weeks is unlikely d. There is no difference in survival between oliguric and nonoliguric renal failure

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Which of the following statement(s) is/are true concerning the antibody response to an invading antigen? a. All antibodies are composed of one type of heavy and one type of light protein chain b. The carboxyl terminus of the heavy chain is the antigen binding site c. Antibody of the immunoglobulin G class is the initial antibody produced in response to an antigenic stimulus d. Immunoglobulins A, D, and E play an active role in the circulating humoral response

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Which of the following statement(s) is/are true concerning the various types of shock? a. Traumatic shock is more commonly associated with subsequent organ injury and multiorgan failure syndrome than hemorrhagic shock b. Cardiogenic shock can be of either an intrinsic or compressive nature c. Hypodynamic septic shock is associated with a decreased mortality risk when compared with hyperdynamic septic shock d. Hypoadrenal shock usually responds quickly to resuscitation e. Neurogenic shock occurs with the absence of sympathetic activity

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The following statement(s) is/are true concerning cellular defense mechanisms. a. Macrophages function solely as antigen processing cells in the initial reaction to exposure to an antigen b. Macrophages may become activated and secrete cytokines c. Macrophages serve as phagocytic cells in the tissues but not within the bloodstream d. Polymorphonucleocytes (PMNS) are normally present in only small numbers within the tissue and enter an area of infection through diapedesis

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Which of the following statement(s) is/are true concerning ischemia reperfusion injury? a. During ischemia, ATP degradation results in increased plasma and intracellular levels of hypoxanthine and xanthene b. Oxygen free radicals such as the superoxide radical are involved in the expression of the proinflammatory phenotype of endothelial cells, macrophages and neutrophils c. The intracellular adhesion molecule-1 (ICAN-1) contributes to injury and disruption of the endothelial lining, with extensive capillary leak and resultant interstitial edema d. Animal models have demonstrated that passive immunization with antibodies to neutrophil adhesive complex lessen the ischemic/reperfusion microvascular injury

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Which of the following statement(s) is/are true concerning protein/amino acid metabolism in man? a. The major source of amino acids is breakdown of circulating proteins b. The recommended daily allowance for protein may triple in critically ill patients c. Urinary nitrogen losses will approach 0 in the face of protein starvation d. Negative nitrogen balance refers to a decrease in nitrogen taken into the body versus the amount of nitrogen lost

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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

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Cytokines with clearly defined actions in acute inflammation and early tissue injury include which of the following? a. Cysteine-X-Cysteine (C-X-C) chemokines b. Tumor Necrosis Factor (TNFa) c. Transforming Growth Factor-b (TGF-b) d. Interleukin-6 (IL-6) e. Platelet Derived Growth Factor (PDGF)

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Last Answer : Answer: a, b, c, d, e Polypeptide mediators, such as TNFa and IL-1, are considered early response cytokines and are actively involved in the initiation of the ... of tissue repair. Thus, coagulation and platelet activation provide the initial foundation for subsequent cellular recruitment

Which of the following statement(s) is/are correct concerning the cardiovascular response to shock? a. Changes in cardiac contractile function shift the Frank Starling curve up and down b. Venoconstriction from skeletal muscle is a significant contributor to the restoration of blood volume with shock c. Arterial vasoconstriction affects all vascular beds equally d. The total circulating blood volume is equally split between the arterial and venous system

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A 55-year-old male undergoes a total abdominal colectomy. Which of the following statement(s) is/are true concerning the hormonal response to the surgical procedure? a. Adrenocorticotropic hormone (ACTH) is secreted from the anterior pituitary gland b. ACTH stimulation results in elevation of serum cortisol levels for up to a week after the operation c. An increased secretion of aldosterone and ADH may contribute to postoperative fluid retention d. An increase in serum insulin and a fall in glucagon accelerate hepatic glucose production and maintain gluconeogenesis

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A 59-year-old trauma patient has suffered multiple septic complications including severe pneumonia, intraabdominal abscess, and major wound infection. He has now developed signs of multisystem organ failure. Which of the following statement(s) is/are true concerning necessary changes to be made in his nutritional management? a. Carbohydrate load should be reduced in the face of respiratory failure b. In patients with renal failure, protein intake should be diminished c. During hemodialysis protein intake should be limited to the same extent d. In patients with hepatic failure, carbohydrate load should be increased

Description : A 59-year-old trauma patient has suffered multiple septic complications including severe pneumonia, intraabdominal abscess, and major wound infection. He has now developed signs of multisystem organ ... the same extent d. In patients with hepatic failure, carbohydrate load should be increased

Last Answer : Answer: a, b The most severe complication of sepsis is multiple system organ dysfunction syndrome, which may result in death. The development of organ failure requires changes in the ... should be provided as fat emulsion. If encephalopathy develops, protein load should also be reduced0

Infectious disease transmission during blood transfusions is of clinical significance to surgeons and of major importance to patients contemplating surgery potentially associated with the need for blood administration. Which of the following statement(s) is/are true concerning the transmission of infectious disease during blood transfusions? a. Post-transfusion hepatitis is usually due to hepatitis B b. Hepatitis and HIV transmission is greatest with the administration of pooled plasma products such as serum albumin c. The most important cause of post-transfusion disease in immunosuppressed patients is CMV infection d. The risk of HIV transmission in blood transfusions is significantly less than the risk of hepatitis transmission

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Last Answer : Answer: c, d The most common infectious diseases transmitted during blood transfusions include viral hepatitis, CMV, and HIV infection. Post-transfusion hepatitis in 90% of cases consists of ... infectious disease transmission, the risks of HIV transmission is markedly less than that of hepatitis

A number of prospective clinical trials have addressed the role of total parenteral nutrition in the cancer patient. The results have been somewhat conflicting. Which of the following statement(s) have been proven correct by prospective trials? a. Preoperative TPN is beneficial in surgical patients with severe preoperative nutrition b. Postoperative TPN is of value following pancreatic resection c. Routine use of perioperative (including prior to the procedure) TPN is of benefit in patients undergoing hepatectomy for hepatoma d. TPN is of no benefit in patients undergoing bone marrow transplant

Description : A number of prospective clinical trials have addressed the role of total parenteral nutrition in the cancer patient. The results have been somewhat conflicting. Which of the following statement(s) ... hepatectomy for hepatoma d. TPN is of no benefit in patients undergoing bone marrow transplant

Last Answer : Answer: a, c Numerous clinical trials have failed to yield a consensus with regard to the efficacy of TPN in cancer patients. In 1991, a multicenter VA cooperative trial demonstrated ... patients receiving bone marrow transplantation has also been shown to be a valuable component of overall care

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

Description : 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. ... d. Visible scarring can occur only when the injury extends deeper than the superficial dermis

Last Answer : 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- ... abrasions and burns may scar significantly. Whenever the dermis is incised, a scar will form

Which of the following statement(s) is/are true concerning the diagnosis and management of hypovolemic shock? a. A fall in hematocrit or hemoglobin always accompanies hemorrhagic shock b. The treatment of shock is generic regardless of the etiology c. Pharmacologic intervention to increase myocardial contractility in hypovolemic shock is an important part the early management d. Complications are less frequent after treatment of hemorrhagic shock than septic or traumatic shock

Description : Which of the following statement(s) is/are true concerning the diagnosis and management of hypovolemic shock? a. A fall in hematocrit or hemoglobin always accompanies hemorrhagic shock b. The ... d. Complications are less frequent after treatment of hemorrhagic shock than septic or traumatic shock

Last Answer : Answer: d Hypovolemic shock is readily diagnosed when there is an obvious source of volume loss and overt signs of hemodynamic instability and increased adrenergic output are present. ... response systems and consequences of their disseminated, indiscriminate cellular injury can be quite profound

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

Description : 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 ... phagocytosis d. Macrophages are a source of a number of humoral factors essential for wound healing

Last Answer : 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 ... . These studies confirm the dominant role of the macrophage and the inflammatory phase of wound healing

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

Description : 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 ... warfarin be continued for at least one year after initial episode of deep venous thrombosis

Last Answer : 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 ... the benefit from anticoagulant therapy and thus is the basis for discontinuing warfarin administration at this time

In the nutritional support of patients with cancer, which of the following statements is/are true? A. Nutritional support benefits the patient's lean body mass but does not enable the tumor to grow. B. In experimental animals, the growth of implanted tumors is directly proportional to the amount of calories and protein supplied. C. Prospective randomized trials of nutritional support utilizing chemotherapy and radiation therapy have revealed benefits to patients receiving total parenteral nutrition. D. Studies of nutritional support for patients with cancer about to undergo surgery revealed decreased morbidity and mortality, especially morbidity from sepsis.

Description : In the nutritional support of patients with cancer, which of the following statements is/are true? A. Nutritional support benefits the patient's lean body mass but does not enable ... with cancer about to undergo surgery revealed decreased morbidity and mortality, especially morbidity from sepsis.

Last Answer : Answer: B DISCUSSION: The problem with the patient with cancer is a very vexing one. Clearly, one of the metabolic effects of cancer, cachexia, affects patients in the last quartile ... undoubtedly reveal that there are certain nutrients that tumors require, which probably should be best avoided

Cytokines are low-molecular-weight polypeptides exerting a wide variety of biologic effects at both local and systemic levels. Which of the following statement(s) is/are true concerning the production and actions of cytokines? a. Cytokines are produced solely by macrophages b. Cytokines act only on other cells within the same local environment c. Cytokines may have both protective and deleterious effects on the host d. Each specific cytokine is produced by a single cell type

Description : Cytokines are low-molecular-weight polypeptides exerting a wide variety of biologic effects at both local and systemic levels. Which of the following statement(s) is/are true concerning the production and ... effects on the host d. Each specific cytokine is produced by a single cell type

Last Answer : Answer: c Macrophages, endothelial cells, lymphocytes, and other cells secrete a large number of different compounds, termed cytokines, that are most probably evolved for the purpose of ... host defenses, exerting both salutatory and deleterious effects on the host, has become increasingly evident

Which of the following statement(s) is/are true concerning the cell function of phagocytosis? a. Phagocytosis is a mechanistically distinct process of endocytosis performed by special cells to take up larger particles such as bacteria or erythrocytes b. Lymphocytes are the primary blood cell involved with this process c. The process involves a coating of the cytoplasmic surface known as clathrin d. Phagocytosis is performed only by white blood cells and tissue macrophages

Description : Which of the following statement(s) is/are true concerning the cell function of phagocytosis? a. Phagocytosis is a mechanistically distinct process of endocytosis performed by special cells to take ... known as clathrin d. Phagocytosis is performed only by white blood cells and tissue macrophages

Last Answer : Answer: a Phagocytosis is a specialized form of endocytosis by which large particles are internalized by specialized cells primarily macrophages and neutrophils. To be phagocytosed, particles ... the lumen of the thyroid follicle, thereby releasing the thyroid hormones, thyroxine triiodothyronine

Which of the following statements about the role of the gut in shock and sepsis are true? A. Selective decontamination of the digestive tract with the use of oral antibiotics has been shown to reduce nosocomial pneumonias and to improve mortality rates. B. Enteral nutrition, as compared with parenteral nutrition, preserves the villus architecture of the gut. C. Gut dysfunction may be an effect of shock, but it may also contribute to the development of MODS by the mechanism of bacterial translocation. D. As compared with parenteral nutrition, enteral nutrition is associated with a reduction in septic morbidity.

Description : Which of the following statements about the role of the gut in shock and sepsis are true? A. Selective decontamination of the digestive tract with the use of oral antibiotics has been ... As compared with parenteral nutrition, enteral nutrition is associated with a reduction in septic morbidity.

Last Answer : Answer: BCD DISCUSSION: The gut has a vital role in the pathophysiology of shock. The splanchnic circulation is very vulnerable to the circulatory redistribution that occurs in shock, thus, gut ... , enteral feeding is more cost effective and is associated with a lower rate of septic morbidity

Under certain circumstances, the gut may become a source of sepsis and serve as the motor of systemic inflammatory response syndrome. Microbial translocation is the process by which microorganisms migrate across the mucosal barrier to invade the host. Which of the following mechanisms can promote bacterial translocation? a. An increased number of gut bacteria b. Altered intestinal mucosal permeability c. Decreased host defense mechanisms d. Lack of enteral feeding

Description : Under certain circumstances, the gut may become a source of sepsis and serve as the motor of systemic inflammatory response syndrome. Microbial translocation is the process by which microorganisms ... intestinal mucosal permeability c. Decreased host defense mechanisms d. Lack of enteral feeding

Last Answer : Answer: a, b, c, d 99 Translocation is promoted in three general ways: 1) altered permeability of the intestinal mucosa as caused by shock, sepsis, distant injury, or cell toxins; 2) ... trauma patient d. Fifty percent of non-nitrogen caloric requirements should be provided in the form of fat

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

Description : 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 ... platelet aggregation d. Spontaneous bleeding is unusual with factor VIII levels greater than 10% of normal

Last Answer : 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 ... factor levels as low as 1% have been noted and patients are at risk for spontaneous bleeding

A 32-year-old man suffers a spinal cord injury with a resultant paraplegia in a motorcycle accident. He presents to the emergency room with hypotension. Which of the following statement(s) is/are true concerning his diagnosis and management? a. The low blood pressure can be assumed to be due to neurogenic shock b. The sole cause of hypotension is the loss of sympathetic input to the venous system c. Despite significant hypotension, secondary organ injury will be uncommon d. There is no role for pharmacologic intervention to maintain blood pressure

Description : A 32-year-old man suffers a spinal cord injury with a resultant paraplegia in a motorcycle accident. He presents to the emergency room with hypotension. Which of the following statement(s) is/ ... injury will be uncommon d. There is no role for pharmacologic intervention to maintain blood pressure

Last Answer : Answer: c Neurogenic shock results from interruption of sympathetic vasomotor input and develops after spinal cord injury, spinal anesthesia, and severe head injury. Under normal conditions, baseline ... the cause is not neurogenic and search for occult blood loss or cardiogenic causes of shock

Which of the following statement(s) is/are true concerning the neuroendocrine responses to shock? a. Sympathetic nerve endings release epinephrine which is responsible for greater than 80% of systemic vascular resistance b. Endogenous epinephrine is the primary contributor to systemic vascular resistance c. Increased pancreatic secretion of glucagon contributes to glucose intolerance associated with injury and sepsis d. The renin-angiotensin axis further augments the sympathetic-mediated vasoconstriction

Description : Which of the following statement(s) is/are true concerning the neuroendocrine responses to shock? a. Sympathetic nerve endings release epinephrine which is responsible for greater than 80% ... injury and sepsis d. The renin-angiotensin axis further augments the sympathetic-mediated vasoconstriction

Last Answer : Answer: c, d The neuroendocrine response to shock attempts to achieve restoration of effective blood volume, mobilization of metabolic substrates, and maintenance of central ... . Angiotensin II is an extremely effective vasoconstrictor that further augments sympathetic-mediated vasoconstriction

Which of the following statements concerning monitoring techniques in the intensive care unit are true? A. Pulmonary artery and pulmonary capillary wedge pressure readings should be made at end inspiration, to minimize ventilatory artifacts. B. Continuous SvO 2 monitoring based on the technique of reflectance spectrophotometry has been shown to be accurate and reliable. C. Direct measurement of gastric intramucosal pH can be provided by gastrointestinal tonometry. D. Hyperlactatemia may be seen in a number of clinical conditions not associated with tissue hypoxia, including liver disease and hypermetabolic states.

Description : Which of the following statements concerning monitoring techniques in the intensive care unit are true? A. Pulmonary artery and pulmonary capillary wedge pressure readings should be made ... clinical conditions not associated with tissue hypoxia, including liver disease and hypermetabolic states.

Last Answer : Answer: BD DISCUSSION: Many different monitoring techniques may be used to assess the adequacy of therapy for shock. The pulmonary artery catheter can provide important hemodynamic and oxygen ... also be seen with liver disease, toxin ingestion, and hypermetabolic states not associated with shock

The following statement(s) is/are true concerning HIV infection. a. Initial screening with ELISA is highly sensitive but can be associated with a false positive rate of 25% b. Treatment with azidothymidine (AZD) appears to prolong survival when administered early in the disease c. Predisposition to infection in HIV infection is primarily due to reduction in the number of helper T cells d. Common infections in patients with AIDS are Pneumocystis, carinii pneumonia, CMV pneumonitis, Cryptococcus meningitis, and disseminated infection due to atypical mycobacteria

Description : The following statement(s) is/are true concerning HIV infection. a. Initial screening with ELISA is highly sensitive but can be associated with a false positive rate of 25% b. ... , carinii pneumonia, CMV pneumonitis, Cryptococcus meningitis, and disseminated infection due to atypical mycobacteria

Last Answer : Answer: b, c, d Acquired immunodeficiency syndrome (AIDS) is a syndrome caused by the human retrovirus (HIV-1) that infects T lymphocytes and causes severe immunosuppression. Individuals who ... to prolong survival when administered early in the course of disease and is considered routine therapy

The initiation of a humoral immune response involves a complex interaction of the antigen, cells and intercellular messengers. Which of the following statement(s) concerning the initiation of the humoral immune response is/are correct? a. Helper T lymphocytes stimulate B lymphocytes through secretion of cytokines such as interleukin 4 and 6 b. A number of cells can aid in presenting the antigen to the helper T cell including B lymphocytes and macrophages c. All antigens require coordinated efforts of the various cellular components of the immune system d. An antigen must be a living microorganism

Description : The initiation of a humoral immune response involves a complex interaction of the antigen, cells and intercellular messengers. Which of the following statement(s) concerning the initiation of the ... various cellular components of the immune system d. An antigen must be a living microorganism

Last Answer : Answer: a, b Stimulation of the immune system occurs after a variety of antigen-presenting cells (B lymphocytes, macrophages, dendritic cells, and Langerhans cells) act to engulf ... polysaccharides), most antigens require coordinated efforts of the various cellular components of the immune system

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 vascu

Description : 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 ... is used to monitor heparin levels intraoperatively during cardiovascular and peripheral vascular operations

Last Answer : 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 ... more while for peripheral vascular applications, values of 250 seconds or greater are considered appropriate

The following statement(s) is/are true concerning initial microbiologic diagnostic techniques. a. Appropriate expeditious transport of specimens to the microbiology laboratory is essential for obtaining accurate clinical information b. The use of potassium hydroxide in preparing a specimen slide for light microscopy will be useful in identification of anaerobic bacteria c. Antibiotic sensitivity is determined by exposing the specific microorganism to varying amounts of antibiotic with the concentration of the antibiotic inhibiting growth referred to as the MIC (minimal inhibitory concentration) d. Serum levels of antimicrobial agents should achieve in excess of a 4-to 8-fold increase over the MIC to be considered clinically efficacious.

Description : The following statement(s) is/are true concerning initial microbiologic diagnostic techniques. a. Appropriate expeditious transport of specimens to the microbiology laboratory is essential for obtaining accurate ... a 4-to 8-fold increase over the MIC to be considered clinically efficacious.

Last Answer : Answer: a, c, d Because most surgical infections are polymicrobial, specimens should be cultured for aerobic and anaerobic bacteria, as well as fungi. Although aerobic and aerotolerant ... fold increase over MIC during the peak serum level have been demonstrated to be clinically efficacious

A 47-year-old patient undergoing a complicated laparotomy for bowel obstruction develops a postoperative enterocutaneous fistula. Which of the following statement(s) is/are true concerning parenteral nutritional support in the postoperative period? a. Oral intake can result in severe dehydration, electrolyte abnormalities, and perifistula skin injury b. Total parenteral nutrition increases the spontaneous closure rate of intestinal fistula c. Total parenteral nutrition decreases mortality rate in patients with intestinal fistulas d. The use of TPN better prepares the patient for surgery if surgical intervention proves necessary

Description : A 47-year-old patient undergoing a complicated laparotomy for bowel obstruction develops a postoperative enterocutaneous fistula. Which of the following statement(s) is/are true concerning parenteral ... use of TPN better prepares the patient for surgery if surgical intervention proves necessary

Last Answer : Answer: a, b, d Patients with gastrointestinal-cutaneous fistulas represent the classical indication for TPN. In such patients, oral intake of food almost invariably results in increased ... treated more aggressively surgically after a defined period of nutritional support (unless closure occurs)

Which of the following statement(s) is/are true concerning the microvascular and cellular response to shock? a. Osmodically induced mobilization of intracellular fluid is the initial response to restore intravascular volume b. With larger volume hemorrhagic shock deterioration of normal cellular transmembrane potential occurs resulting in an increase in extracellular sodium and water c. The accumulation of anaerobic metabolites override normal homeostatic vasomotor tone and contribute to the maladaptive vasodilatation d. Abnormal intracellular calcium homeostasis may contribute to the cellular dysfunction of shock

Description : Which of the following statement(s) is/are true concerning the microvascular and cellular response to shock? a. Osmodically induced mobilization of intracellular fluid is the initial ... d. Abnormal intracellular calcium homeostasis may contribute to the cellular dysfunction of shock

Last Answer : Answer: c, d Moderate hypovolemia results in a relatively rapid spontaneous restitution of intravascular volume through expansion of the plasma space. This plasma expansion by ... potassium pump. Cellular dysfunction also appears to be related to abnormal intracellular calcium homeostasis

Most hormone receptors are localized on the cell membrane and transduce hormone binding into altered levels of intracellular messengers. A limited number of intracellular receptors do exist. Which of the following statement(s) is/are true concerning intracellular receptors? a. The messengers or hormones must by lipophilic b. These intracellular receptors generally regulate protein synthesis c. The intracellular receptors are located entirely in the nucleus of the cell d. A heat-shock protein serves as an inhibitor protein blocking the DNA-binding domain of the steroid receptor

Description : Most hormone receptors are localized on the cell membrane and transduce hormone binding into altered levels of intracellular messengers. A limited number of intracellular receptors do exist. Which of ... protein serves as an inhibitor protein blocking the DNA-binding domain of the steroid receptor

Last Answer : Answer: a, d Although most hormone and other messenger receptors are extracellular, intracellular receptors have been identified. The hormone messengers involved for these receptors are primarily ... DNA-binding domain of the receptor. Activation involves the dissociation of the inhibitor protein

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

Description : 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 ... Histamine, prostaglandin E2 (PGE2) and prostacyclin (PGI2) are important mediators of local vasoconstriction

Last Answer : 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 ... and mast cells and enhance the egress of cells and substrate into the wound and tissue