Which of the following statement(s) is/are true concerning O2 venous saturation monitoring? a. The normal saturation of mixed venous blood is 50% b. Mixed venous blood obtained for saturation monitoring can be obtained from any peripheral vein c. If arterial blood is fully saturated, the saturation of mixed venous blood is 80% d. In less than fully saturated blood, the difference between arterial and venous saturation corresponds to oxygen extraction

Which of the following statement(s) is/are true concerning O2 venous saturation monitoring?  a. The normal saturation of mixed venous blood is 50% b. Mixed venous blood obtained for saturation monitoring can be obtained from any peripheral vein c. If arterial blood is fully saturated, the saturation of mixed venous blood is 80% d. In less than fully saturated blood, the difference between arterial and venous saturation corresponds to oxygen extraction
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Answer: c, d  The relationship between oxygen delivery and oxygen consumption is reflected in the amount of oxygen in venous blood. Under normal circumstances, oxygen delivery is 1000 cc/min and oxygen consumption is 200 cc/min. The amount of oxygen extracted is 20% of that delivered, and 80% of oxygen is still present in venous blood returning to the heart. Usually arterial blood is fully saturated, and under normal circumstances, the saturation of mixed venous blood (SVO2) will be 80%. This measurement must be made in mixed venous blood since the relative extraction of organs served by the superior and inferior vena cava and coronary sinus are quite different. As long as arterial blood is fully saturated, this observation holds true regardless of the absolute level of oxygen consumption or oxygen delivery. If the arterial blood is less than fully saturated, the difference between arterial and venous saturation corresponds to the oxygen extraction, hence the oxygen delivery/oxygen consumption ratio
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Which of the following statement(s) is/are true concerning oxygen delivery? a. The amount of oxygen delivered to peripheral tissues is dependent upon the oxygen content in arterial blood and cardiac output b. Oxygen content is commonly measured in arterial blood c. The normal arterial-venous difference is 4 cc O2/dL d. Normal systemic oxygen delivery for a typical adult is approximately 1000 cc/min

Description : Which of the following statement(s) is/are true concerning oxygen delivery? a. The amount of oxygen delivered to peripheral tissues is dependent upon the oxygen content in arterial blood and cardiac ... O2/dL d. Normal systemic oxygen delivery for a typical adult is approximately 1000 cc/min

Last Answer : Answer: a, c, d The amount of oxygen that is delivered to peripheral tissues is the product of the oxygen content in arterial blood times the cardiac output. Normally, oxygen content of arterial blood is ... of venous blood is 16 cc/dL. Hence, the normal arterial-venous difference is 4 cc O2/dL

Useful steps to optimize systemic oxygen delivery include: a. Maintaining mean arterial blood pressure between 50 and 90 mm Hg b. Optimizing PEEP levels by monitoring mixed venous saturation c. Turning the patient prone d. Sedation or paralysis

Description : Useful steps to optimize systemic oxygen delivery include: a. Maintaining mean arterial blood pressure between 50 and 90 mm Hg b. Optimizing PEEP levels by monitoring mixed venous saturation c. Turning the patient prone d. Sedation or paralysis

Last Answer : Answer: a, b, c, d Optimizing systemic oxygen delivery in relationship to oxygen requirement is the primary goal of management. Improving oxygenation of the blood itself by ... sedation, and establishing muscular paralysis decrease oxygen consumption, and decrease the need for oxygen delivery

Which of the following statement(s) is/are true concerning the pathophysiology of gas exchange? a. Hypoventilation in relation to perfusion can result in an oxygen saturation of less than 100% b. Diffusion block and / mismatch can almost completely be overcome by breathing 100% oxygen c. Transpulmonary shunting does not occur under normal circumstances d. The normal arterial oxygen saturation should be 100%

Description : Which of the following statement(s) is/are true concerning the pathophysiology of gas exchange? a. Hypoventilation in relation to perfusion can result in an oxygen saturation of less than 100% ... does not occur under normal circumstances d. The normal arterial oxygen saturation should be 100%

Last Answer : Answer: a, b Under normal conditions, red blood cells in the pulmonary capillaries become fully saturated and oxygen dissolves in plasma resulting in blood PO2 of 100 and O2 saturation of 100%. This ... the fact that normal arterial PO2 is 90-100 mm Hg and the normal O2 saturation is 98%

Which of the following statement(s) concerning intravenous nutritional support is/are true? a. Concentrations of glucose no higher than 5% should be used to avoid peripheral vein sclerosis b. A major disadvantage of the peripheral technique is limited caloric delivery c. If total parenteral nutrition is required, access to the superior vena cava via the external jugular vein is the most suitable site d. Venous thrombosis is an uncommon complication for long-term central vein catheterization

Description : Which of the following statement(s) concerning intravenous nutritional support is/are true? a. Concentrations of glucose no higher than 5% should be used to avoid peripheral vein sclerosis ... suitable site d. Venous thrombosis is an uncommon complication for long-term central vein catheterization

Last Answer : Answer: b Although peripheral access can be used for intravenous nutrition, the major disadvantage of this technique is limited caloric delivery to meet catabolic demands within tolerated fluid ... studies that use phlebography or radionucleotide venography indicate the incidence is as high as 35%

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

Description : 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. ... d. The total circulating blood volume is equally split between the arterial and venous system

Last Answer : Answer: a Central in the general cardiovascular response to shock is the action of the heart itself. The principle determinants of cardiac function in the normal heart are the volume of blood ... Blood flow to the skin is sacrificed early, followed by that to the kidneys and splanchnic viscera

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 thrombus b. If progress is made, further fibrinolytic therapy is given at 1000 to 2000 units per minute until clot lysis has occurred c. The usual infusion time by the above-stated technique is usually in excess of 24 hours d. Successful clot lysis occurs more frequently in arterial graf

Description : 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 ... may be indicated for situations where complete clot evacuation cannot be accomplished surgically

Last Answer : 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 ... acute arterial occlusion) or when distal vasculative is occluded and precludes appropriate inflow patency

Which of the following statement(s) is/are true concerning the results of a National Institute of Health Consensus Conference on venous thrombosis and low-dose heparin prophylaxis? a. The odds of developing deep venous thrombosis with low-dose heparin prophylaxis decreases by 67% b. The risk of pulmonary embolism is decreased by almost 50% c. There is no increase in mortality from other causes found in patients treated with low-dose heparin d. There was no difference in the incidence of bleeding complications

Description : Which of the following statement(s) is/are true concerning the results of a National Institute of Health Consensus Conference on venous thrombosis and low-dose heparin prophylaxis? a. The odds of ... treated with low-dose heparin d. There was no difference in the incidence of bleeding complications

Last Answer : Answer: a, b, c In a metaanalysis of 70 randomized trials in 16,000 patients comparing low-dose heparin prophylaxis with standard therapy, the odds of developing deep venous thrombosis ... Similarly, the effectiveness of prophylaxis was not influenced by either two or three times daily dosage

Which of the following statement(s) is/are true concerning methods of nutritional support? a. Optimal results for enteral feedings are achieved with approximately half of calories supplied as carbohydrate and half as fat b. Diarrhea is the most common complication of enteral feeds and is due to the high osmolarity of the carbohydrate components c. The hyperosmolar nature of parenteral fat solutions requires central venous administration d. Approximately 25–50% of calories should be provided as fat emulsion in patients receiving total parenteral nutrition

Description : Which of the following statement(s) is/are true concerning methods of nutritional support? a. Optimal results for enteral feedings are achieved with approximately half of calories supplied as ... -50% of calories should be provided as fat emulsion in patients receiving total parenteral nutrition

Last Answer : Answer: a, b, d Most formulas for enteral feeding range from 1.0 to 2 cal/ml and include 3 to 7% protein. Most of the calories are supplied as glucose or sucrose, so that the solutions ... up to 25 to 50% of calories each day as fat emulsion may optimize the delivery of this caloric delivery

Bleeding complications are frequently associated with fibrinolytic therapy. Which of the following statement(s) concerning complications of fibrinolytic therapy is/are true? a. Careful monitoring of prothrombin time and aPTT time are necessary to avoid bleeding complications b. A level of serum fibrinogen less than 100 mg/dl is associated with an increased risk of bleeding c. Recent (less than 10 days) major surgery is a contraindication to systemic but not regional fibrinolytic therapy d. A patient with a cerebrovascular event occurring less than two months ago can be treated with fibrinolytic therapy if head CT scan is normal

Description : Bleeding complications are frequently associated with fibrinolytic therapy. Which of the following statement(s) concerning complications of fibrinolytic therapy is/are true? a. Careful monitoring of prothrombin time ... months ago can be treated with fibrinolytic therapy if head CT scan is normal

Last Answer : Answer: b Fibrinolytic therapy induces a hemostatic defect through a combination of factors. Hypofibrinogenemia and fibrin degradation products inhibit fibrin polymerization and, in combination ... is considered a major relative contraindication to either regional or systemic thrombolytic therapy

Which of the following statement(s) is/are true concerning carbon dioxide kinetics? a. The amount of carbon dioxide produced is equivalent to the amount of oxygen consumed b. Carbon dioxide levels in blood, present mostly as a bicarbonate ion, can quickly change c. Normally the amount of carbon dioxide excreted through the lung is exactly equal to the amount of carbon dioxide produced in peripheral tissues d. The amount of carbon dioxide excreted is a function of ventilation of perfused alveoli

Description : Which of the following statement(s) is/are true concerning carbon dioxide kinetics? a. The amount of carbon dioxide produced is equivalent to the amount of oxygen consumed b. Carbon dioxide levels ... tissues d. The amount of carbon dioxide excreted is a function of ventilation of perfused alveoli

Last Answer : Answer: a, c, d The total amount of carbon dioxide produced by systemic metabolism is roughly equivalent to the amount of oxygen consumed (100-120 cc/m2/min, 200 cc/min in a typical ... carbon dioxide excreted is a function of ventilation of perfused alveoli (i.e. the alveolar ventilation/min).

Which of the following statement(s) is/are true concerning CO2 transfer in the lung? a. Carbon dioxide excretion is a direct function of alveolar ventilation b. Normally end tidal CO2 should be identical to PaCO2 c. The gradient between end tidal and arterial CO2 can be an indirect measure of nonperfused alveoli d. Positive pressure ventilation under normal airway pressures creates a significant end tidal PaCO2 gradient

Description : Which of the following statement(s) is/are true concerning CO2 transfer in the lung? a. Carbon dioxide excretion is a direct function of alveolar ventilation b. Normally end tidal ... d. Positive pressure ventilation under normal airway pressures creates a significant end tidal PaCO2 gradient

Last Answer : Answer: a, b, c The amount of carbon dioxide excretion is directly related to alveolar ventilation. While oxygenation is a function of matching blood flow to alveoli, carbon dioxide excretion is ... high (over 30 cm H2O) and the compression volume is a significant component of each exhaled breath

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 oxygen consumption (O2)? a. O2 is normally 100–120 cc2/m2/min b. Resting O2 is controlled by the level of thyroid and catecholamine hormones c. Under steady state conditions the amount of oxygen consumed exceeds the amount of oxygen taken up by the pulmonary capillaries d. O2 is dependent on the status of pulmonary function

Description : Which of the following statement(s) is/are true concerning oxygen consumption (O2)? a. O2 is normally 100-120 cc2/m2/min b. Resting O2 is controlled by the level of thyroid and catecholamine ... of oxygen taken up by the pulmonary capillaries d. O2 is dependent on the status of pulmonary function

Last Answer : Answer: a, b Oxygen consumed in the process of metabolism is expressed as the volume of oxygen per minute (O2). O2 is normally 100-120 cc2/m2/min, or 200 cc/min for a typical adult. ... , so we measure O2 across the lung and assume that it is exactly the amount consumed in the systemic metabolism

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

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

Description : 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 ... -treatment for elective surgery require administration of cryoprecipitate to achieve levels of 23-50% of normal

Last Answer : 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 ... platelet aggregation responses to ristocetin. The most reliable source of Von Willebrand's factor is cryoprecipitate

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

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

Description : 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 ... includes through the operation and for at least several days in the postoperative period

Last Answer : 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 ... be used through the operation and for at least five days in the face or prolonged immobilization

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

Description : 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 ... serum creatinine should be measured daily to allow adjustments in dose based on renal function

Last Answer : 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 ... system. Therefore the dose of heparin need not be adjusted in cases of liver or renal dysfunction

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

The following statement(s) is/are true concerning gram-negative bacterial sepsis. a. Mortality due to this condition has almost been eliminated due to therapeutic intervention with antibiotics, aggressive hemodynamic monitoring and fluid resuscitation b. Recent series have noted a decrease in the incidence of this condition c. Predisposing factors include old age, malnutrition, and immunosuppression d. Pseudomonas bacteremia is the most common cause of gram-negative sepsis e. Polymicrobial sepsis is generally considered a more serious problem than sepsis due to a single organism

Description : The following statement(s) is/are true concerning gram-negative bacterial sepsis. a. Mortality due to this condition has almost been eliminated due to therapeutic intervention with antibiotics, aggressive ... sepsis is generally considered a more serious problem than sepsis due to a single organism

Last Answer : Answer: c, e Gram-negative bacterial sepsis is a serious disease process that produces substantial morbidity and mortality in both normal and immunocompromised patients (10% to 20% and ... and most investigators agree that polymicrobial sepsis is more lethal than infection with a single organism

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

Description : 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 ... is unlikely d. There is no difference in survival between oliguric and nonoliguric renal failure

Last Answer : Answer: a, b, c Survival of patients with acute renal failure is a function of the successful treatment of the primary disease from which the renal failure was derived. The mortality ... is unlikely. Nonoliguric renal failure is usually limited in its extent and is almost always reversible

A 17-year-old patient involved in an automobile accident is paralyzed with multiple peripheral extremity injuries. Nutritional support is instituted with a transnasal feeding catheter. Which of the following statement(s) is/are true concerning the patient’s management? a. Feeding into the stomach results in stimulation of the biliary/pancreatic axis which is probably trophic for small bowel b. Gastric secretions will dilute the feedings increasing the risk of diarrhea c. The major risk in this patient is tracheobronchial aspiration d. Placement of the feeding catheter through the pylorus into the first portion of the duodenum reduces the risk of regurgitation and aspiration

Description : A 17-year-old patient involved in an automobile accident is paralyzed with multiple peripheral extremity injuries. Nutritional support is instituted with a transnasal feeding catheter. Which of the ... pylorus into the first portion of the duodenum reduces the risk of regurgitation and aspiration

Last Answer : Answer: a, c, d The use of transnasal feeding catheters for intragastric feeding or for duodenal intubation are popular adjuncts for providing nutritional support by the enteral route. The ... the fourth portion of the duodenum reduces the risk of regurgitation and aspiration of feeding formulas

There are a number of hypercoaguable states which can be associated with arterial or venous thrombosis and embolic phenomenon. These include: a. Heparin-associated thrombocytopenia b. Antithrombin III deficiency c. Von Willebrand disease d. Vitamin C deficiency

Description : There are a number of hypercoaguable states which can be associated with arterial or venous thrombosis and embolic phenomenon. These include: a. Heparin-associated thrombocytopenia b. Antithrombin III deficiency c. Von Willebrand disease d. Vitamin C deficiency

Last Answer : Answer: a, b A number of hypercoaguable states are present. These include heparin-associated thrombocytopenia in which a heparin-dependent platelet antibody causes aggregation of ... soft tissue increasing vascular permeability and fragility resulting in the potential for bleeding disorders

Which of the following statement(s) is/are true concerning oxygen kinetics in a critically ill, febrile patient? a. Oxygen consumption will likely exceed three times normal b. The high cardiac output and pulse rate are designed to increase oxygen delivery c. The hyperdynamic response may actually increase oxygen delivery to exceed the increase in oxygen consumption d. The patient can maintain adequate compensation as long as the oxygen delivery/oxygen consumption rate is greater than 2:1

Description : Which of the following statement(s) is/are true concerning oxygen kinetics in a critically ill, febrile patient? a. Oxygen consumption will likely exceed three times normal b. The high cardiac ... adequate compensation as long as the oxygen delivery/oxygen consumption rate is greater than 2:1

Last Answer : Answer: b, d In critically ill patients oxygen consumption may be elevated or depressed, but slight to moderate elevations in oxygen consumption is the most common abnormality in critically ill patients. ... however, and the patient will remain stable as long as the ratio is greater than 2:1

Which of the following statement(s) is/are true concerning the autoregulation necessary to maintain oxygen consumption and oxygen delivery? a. A change in oxygen consumption is followed by a proportionate change in oxygen delivery b. A change in oxygen delivery is followed by a change in oxygen consumption c. Increases in oxygen delivery are due solely to an increase in cardiac output d. The normal ratio of oxygen delivery to consumption is 2:1

Description : Which of the following statement(s) is/are true concerning the autoregulation necessary to maintain oxygen consumption and oxygen delivery? a. A change in oxygen consumption is followed by a proportionate ... increase in cardiac output d. The normal ratio of oxygen delivery to consumption is 2:1

Last Answer : Answer: a The relationships between oxygen consumption and oxygen delivery represent one of the most interesting regulation systems in homeostasis. First of all, if one of the three components ... in oxygen consumption. The normal ratio of oxygen delivery to consumption is approximately 5:1

A 67-year-old male presents with an intraabdominal abscess secondary to perforated sigmoid diverticulitis. The following statement(s) is/are true concerning his intraabdominal abscess. a. Culture will likely reveal a solitary organism b. Both aerobic and anaerobic islets are encountered in 50% of specimens c. The most common aerobic islet will be likely E. coli and other gram-negative enteric bacilli d. The most common anaerobic islet will be a Bacteroides species

Description : A 67-year-old male presents with an intraabdominal abscess secondary to perforated sigmoid diverticulitis. The following statement(s) is/are true concerning his intraabdominal abscess. a. Culture will ... gram-negative enteric bacilli d. The most common anaerobic islet will be a Bacteroides species

Last Answer : Answer: b, c, d Typically an intraabdominal infection results in perforation of a hollow viscus and the ensuing contamination of a normally sterile peritoneal cavity. The normal ... Bacteroides species (especially B. fragilis, Clostridium), and anaerobic cocci are most consistently isolated

A 68-year-old male who underwent a repair of an abdominal aortic aneurysm 5 days ago, develops tachycardia, tachypnea, hypotension with cool, pale, mottled cyanotic extremities. He is agitated and complains of shortness of breath. Which of the following statement(s) is/ are correct concerning his diagnosis and management? a. Myocardial ischemia secondary to preexisting coronary artery disease is most likely the underlying cause of this problem b. Invasive hemodynamic monitoring with a Swan-Gantz catheter will demonstrate a low cardiac output, a high systemic vascular resistance, and elevated cardiac filling pressures c. The use of morphine sulphate and nitrates should be part of the initial management d. The primary pharmacologic treatment involves the use of moderate doses of inotropic ag

Description : A 68-year-old male who underwent a repair of an abdominal aortic aneurysm 5 days ago, develops tachycardia, tachypnea, hypotension with cool, pale, mottled cyanotic extremities. He ... use of moderate doses of inotropic agents e. Afterload reduction with nitroprusside is absolutely contraindicated

Last Answer : Answer: a, b, d Intrinsic cardiogenic shock results from failure of the heart as an effective pump. Coronary artery disease is the most common cause of myocardial ... hemodynamic monitoring. Infusion of afterload-reducing agents can be administered in conjunction with inotropic support

Laboratory monitoring of coagulation and anticoagulation includes testing of platelet function. Which of the following statements is/are true concerning tests of platelet function? a. A platelet count of 50,000/µL or more usually ensures hemostasis b. Bleeding time assays assessibility of platelets to perform hemostatic plugs and is determined from a sample of blood drawn in an EDTA coated test tube c. Aspirin therapy can be associated with a bleeding time in the range of 8–15 minutes d. Tests of platelet aggregation should be part of the standard preoperative evaluation of patients using aspirin

Description : Laboratory monitoring of coagulation and anticoagulation includes testing of platelet function. Which of the following statements is/are true concerning tests of platelet function? a. A ... platelet aggregation should be part of the standard preoperative evaluation of patients using aspirin

Last Answer : Answer: a, c Tests of platelet function include peripheral platelet counts, bleeding times, and platelet aggregation. Usually, a platelet count of 50,000/mL or more ensures adequate hemostasis ... is not available in most laboratories, probably because of the observer-dependent nature of the test

Which of the following statement(s) is/are true concerning septic shock? a. The clinical picture of gram negative septic shock is specifically different than shock associated with other infectious agents b. The circulatory derangements of septic shock precede the development of metabolic abnormalities c. Splanchnic vascular resistance falls in similar fashion to overall systemic vascular resistance d. Despite normal mechanisms of intrinsic expansion of the circulating blood volume, exogenous volume resuscitation is necessary

Description : Which of the following statement(s) is/are true concerning septic shock? a. The clinical picture of gram negative septic shock is specifically different than shock associated with ... mechanisms of intrinsic expansion of the circulating blood volume, exogenous volume resuscitation is necessary

Last Answer : Answer: d The clinical findings in sepsis and septic shock represent the host response to infection. Gram-positive and gram-negative bacteria, viruses, fungi, rickettsiae, and ... intravascular volume, exogenous volume resuscitation must be provided to restore venous return and ventricular filling

Which of the following statement(s) is/are true concerning the relationship between cardiac function and effective blood volume? a. A pulmonary capillary wedge pressure of 5–10 rules out fluid overload as a cause of pulmonary edema b. A shift to the right in the Frank-Starling curve is associated with compromised cardiac function c. Dilutional anemia may contribute to tachycardia even though blood volume and filling pressures are normal d. The sole purpose of a pulmonary artery catheter is to measure pulmonary artery pressure and cardiac output

Description : Which of the following statement(s) is/are true concerning the relationship between cardiac function and effective blood volume? a. A pulmonary capillary wedge pressure of 5-10 rules out ... sole purpose of a pulmonary artery catheter is to measure pulmonary artery pressure and cardiac output

Last Answer : Answer: b, c Although physical findings are often adequate to establish a diagnosis and institute management of cardiac failure, direct measurement of filling pressures of the right heart ( ... blood volume is normal, filling pressures are normal, and total body extracellular fluid is excessive

Which of the following statement(s) is/are true concerning the treatment of MOFS? a. Prevention and therapy of MOFS requires control of the infectious or inflammatory source b. Restoration of normal clinical parameters such as blood pressure, pulse rate, and urine output ensures optimal resuscitation in most patients c. Branch chain amino acids play and important role in the nutritional support of the patient d. Because of the nature of gut injury, total parenteral nutrition is preferred for most patients with MOFS

Description : Which of the following statement(s) is/are true concerning the treatment of MOFS? a. Prevention and therapy of MOFS requires control of the infectious or inflammatory source b. Restoration of normal ... of the nature of gut injury, total parenteral nutrition is preferred for most patients with MOFS

Last Answer : Answer: a, c The therapy of MOFS is directed towards interrupting the involving pathophysiologic process and providing an optimal physiologic environment for healing and recovery. ... Enteral absorption and processing of nutrients appears superior to TPN and lessens overall complications

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

Description : 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 ... transmission in blood transfusions is significantly less than the risk of hepatitis transmission

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

Which of the following statements concerning perioperative nutrition is true concerning the above-described patient? a. Since the patient’s weight had been stable with no preoperative nutritional deficit, 5% dextrose intravenous solutions are adequate for the initial postoperative source of nutrition b. Preoperative immunologic status should be determined including total peripheral lymphocyte count and delayed hypersensitivity reaction to determine skin-test response to common antigens c. Routine postoperative fluid administration with intravenous 5% glucose solutions can provide the calories to meet basal energy requirements d. A jejunal feeding catheter should be placed at the time of surgery for postoperative enteral feeding

Description : Which of the following statements concerning perioperative nutrition is true concerning the above-described patient? a. Since the patient's weight had been stable with no preoperative nutritional deficit ... feeding catheter should be placed at the time of surgery for postoperative enteral feeding

Last Answer : Answer: a Most patients undergoing elective operations are adequately nourished. Unless the patient has suffered significant preoperative malnutrition, characterized by weight loss greater than ... gastrointestinal surgery, this technique would not appear indicated in the patient described above

Which of the following statements(s) is/are true concerning human energy requirement? a. In normal subjects, less than 5% of basal energy requirement is spent on cardiac output and the work of breathing b. Mechanical ventilation can decrease the energy expenditure for normal respiration c. For a 70 kg male, average resting energy consumption is almost 1500 kcal/day d. Similar increases in energy expenditures are associated with elective surgery and trauma or thermal injury

Description : Which of the following statements(s) is/are true concerning human energy requirement? a. In normal subjects, less than 5% of basal energy requirement is spent on cardiac output and the ... d. Similar increases in energy expenditures are associated with elective surgery and trauma or thermal injury

Last Answer : Answer: a, c Basal energy requirements are measured with the subject at rest when no external work is being done; the energy is used mainly for transport and synthetic work within cells. A ... average-sized adult who sustains a major burn rarely may require more than 3500 kcal/day for maintenance

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

Description : 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 ... immunization with antibodies to neutrophil adhesive complex lessen the ischemic/reperfusion microvascular injury

Last Answer : Answer: a, b, c, d During the ischemia and hypoperfusion phase, degradation of ATP stores essential to maintain cell integrity and significant loss of diffusible ... either the neutrophil adhesive complex or the endothelial selectins dramatically lessens ischemia/reperfusion microvascular injury

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

Description : 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 ... d. The extent of increase in oxygen consumption relates to the severity of the infection

Last Answer : Answer: a, c, d Oxygen consumption is usually elevated in the infected patient. The extent of this increase is related to the severity of the infection, with peak elevations reaching 50% ... suggest that the metabolic rate increases 10% to 13% for each elevation of 1°C in central temperature

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

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

Rank the following laboratory tests and procedures in terms of their relative value to a 65-year-old woman who is to undergo elective resection of a sigmoid cancer. A. Carcinoembryonic antigen (CEA). B. Blood urea nitrogen (BUN). C. Electrocardiogram (ECG). D. Hemoglobin concentration (Hgb). E. Serum creatinine (Cr). F. Arterial blood oxygen tension (PaO 2) on room air. G. Serum sodium concentration (Na+).

Description : Rank the following laboratory tests and procedures in terms of their relative value to a 65-year-old woman who is to undergo elective resection of a sigmoid cancer. A. Carcinoembryonic antigen (CEA). B. ... Arterial blood oxygen tension (PaO 2) on room air. G. Serum sodium concentration (Na+).

Last Answer : Answer: CDFEBAG DISCUSSION: The most important test by far is the electrocardiogram, with its capacity to indicate signs of occult heart disease. The second most important evaluation is the hemoglobin ... for resection of the colon is always normal and would be of least value among these tests

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

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

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

Description : 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 ... unwounded skin d. The proteoglycans are responsible for the ground substance of the extracellular matrix

Last Answer : 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 ... in strength for six months or more, eventually reaching 70% of the strength of unwounded skin

Concerning the mixture of arterial with venous blood what is the difference between the human fetal circulation and the adult circulation?

Description : Concerning the mixture of arterial with venous blood what is the difference between the human fetal circulation and the adult circulation?

Last Answer : In the human fetal circulation there are two communications between arterial and venous blood characterizing an incomplete circulation. One of them is the oval foramen, an opening between the right and the left ... close a few days after birth and so they are not present in the adult heart.

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 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

Description : 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 ... observed e. A new recombinant preparation of factor VIII offers the advantage of being virus-free

Last Answer : 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 ... infection in the hemophilia population. A new recombinant preparation of factor VIII offers the advantage of being virus-free

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 therapy

Description : 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. ... d. Heparin-associated thrombocytopenia may be seen within hours of initiation of heparin therapy

Last Answer : 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 ... as coating on pulmonary artery catheters or low rate infusion into arterial catheters may cause this syndrome

Which of the following statement(s) is/are true concerning metabolic derangements in sepsis and the systemic inflammatory response syndrome which may follow progressive shock? a. Alterations in glucose metabolism lead to the development of efficient substrate utilization b. A progressive rise in serum triglyceride levels result from less efficient clearance and increased hepatic lipogenesis c. A net negative nitrogen balance occurs due to the oxidative metabolism of proteins to meet energy needs d. The serum aromatic amino acids fall rapidly as they are actively used in oxidative metabolism

Description : Which of the following statement(s) is/are true concerning metabolic derangements in sepsis and the systemic inflammatory response syndrome which may follow progressive shock? a. Alterations in glucose ... The serum aromatic amino acids fall rapidly as they are actively used in oxidative metabolism

Last Answer : Answer: b, c A broad spectrum of metabolic abnormalities become apparent in sepsis and the systemic inflammatory response syndrome following shock. Disruption of the normal cycles of carbohydrate, ... acetyl coenzyme A. This results in reduced serum level of leucine, isoleucine and valine

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

Description : 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 ... Cytokine release may stimulate the release of other cytokines leading to an important cascade of events

Last Answer : Answer: a, d Cytokines, which are produced at the site of injury by endothelial cells and by diverse immune cells throughout the body, also occupy a pivotal position in the stress response ... act as hormones and spill over into the systemic circulation and become detectable in the bloodstream

Which of the following statement(s) is/are true concerning the treatment of pulmonary interstitial edema? a. Diuresis and blood transfusion is a valuable step b. Salt-poor albumin leaks through the capillaries and worsens the condition c. Mannitol is contraindicated as a diuretic in this clinical situation d. Isoproterenol is a poor choice as an ionotropic agent

Description : Which of the following statement(s) is/are true concerning the treatment of pulmonary interstitial edema? a. Diuresis and blood transfusion is a valuable step b. Salt-poor albumin leaks through the ... a diuretic in this clinical situation d. Isoproterenol is a poor choice as an ionotropic agent

Last Answer : Answer: a Treatment of pulmonary edema has two important goals, the first is to improve oxygenation if it is impaired, and the second is to minimize fibrosis and bacterial infection, which often ... leaks out , the short term effects of expanding blood volume and decrease in edema will appear

Which of the following statement(s) is/are true concerning the physiology of the microvascular system? a. Filtration of capillary fluid into the interstitial and the subsequent reabsorption is influenced by Starling’s law of ultrafiltration b. The most important variable controlling blood to a capillary bed is the length of the vessel c. Most of the resistance to systemic blood flow occurs at the arteriolar level d. Adrenergic vasoconstriction can arrest blood flow to an entire capillary bed

Description : Which of the following statement(s) is/are true concerning the physiology of the microvascular system? a. Filtration of capillary fluid into the interstitial and the subsequent reabsorption is ... the arteriolar level d. Adrenergic vasoconstriction can arrest blood flow to an entire capillary bed

Last Answer : Answer: a, c, d Exchange of material between the vascular space and the cell of various tissues via the interstitial space is essential for organ viability and occurs at the ... contractions are potent enough that blood flow to entire capillary beds can be arrested by adrenergic vasoconstriction