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NPTE practice questions

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Question 1Body System Interactions

A patient with heart failure reports worsening shortness of breath when lying flat and needs three pillows to sleep. Which mechanism best explains this orthopnea?

  1. Decreased diaphragmatic excursion as the sole contributing factor
  2. Bronchospasm triggered by recumbency
  3. Increased central blood volume raising pulmonary capillary pressure Correct answer.
  4. Reduced alveolar surface tension in the supine position

Explanation

Supine positioning redistributes blood from the dependent extremities and splanchnic bed into the thorax, raising pulmonary capillary hydrostatic pressure and favoring transudation into the interstitium. The resulting congestion reduces lung compliance and increases the work of breathing, so orthopnea is a marker of elevated left-sided filling pressures.

Question 2Body System Interactions

During the straining phase of a Valsalva maneuver, which cardiovascular response is expected?

  1. Reduced venous return with a transient fall in blood pressure Correct answer.
  2. Increased venous return with a rise in stroke volume
  3. Isolated rise in pulmonary artery pressure with unchanged cardiac output
  4. Bradycardia caused by increased carotid sinus stretch

Explanation

Straining raises intrathoracic pressure, compressing the great veins and impeding venous return, so stroke volume and cardiac output fall and blood pressure drops transiently. Baroreflex vasoconstriction and tachycardia then restore pressure; the bradycardia classically occurs after release of the strain.

Question 3Body System Interactions

Which factor most helps maintain venous return during rhythmic upright exercise?

  1. Increased intrathoracic pressure from accessory muscle use
  2. Rhythmic skeletal muscle contraction with competent venous valves Correct answer.
  3. Gravity-assisted flow through deep veins
  4. A fall in right atrial pressure from reduced preload

Explanation

Contracting muscle bellies compress the deep veins while one-way valves direct blood toward the heart, and intermittent relaxation allows the veins to refill. This muscle pump counteracts the gravitational pooling that would otherwise occur in the lower extremities during upright activity.

Question 4Body System Interactions

A patient with moderate iron-deficiency anemia exercises at a fixed submaximal workload. Which response is expected compared with a person who does not have anemia?

  1. An increased arterial oxygen content from a rightward shift of the oxyhemoglobin curve
  2. A higher heart rate to compensate for reduced arterial oxygen content Correct answer.
  3. A lower heart rate from reduced blood viscosity
  4. A lower minute ventilation at the same oxygen uptake

Explanation

Fewer functional hemoglobin molecules lower arterial oxygen content, so a given absolute workload demands a higher cardiac output and heart rate to deliver the same amount of oxygen. Ventilation also tends to rise, and a rightward curve shift lowers saturation rather than improving content.

Question 5Body System Interactions

A patient with a 20-year history of type 1 diabetes has restricted active and passive shoulder elevation in all planes. Which mechanism best explains this finding?

  1. Acute inflammatory bursitis related to hyperglycemia
  2. Nonenzymatic glycosylation of collagen with cross-linking of periarticular tissue Correct answer.
  3. Diabetic nephropathy causing fluid retention in the joint capsule
  4. Peripheral neuropathy causing muscle imbalance

Explanation

Chronic hyperglycemia drives formation of advanced glycation end-products that cross-link collagen, stiffening skin, tendons, and joint capsule. This limited joint mobility syndrome commonly presents as adhesive capsulitis with restriction in multiple planes.

Question 6Body System Interactions

Which finding most directly reflects an increased basal metabolic rate in a patient with hyperthyroidism?

  1. Resting bradycardia
  2. Diminished deep tendon reflexes
  3. Weight loss despite preserved or increased caloric intake Correct answer.
  4. Cold intolerance

Explanation

Thyroid hormone raises oxygen consumption and heat production in most tissues, so energy expenditure exceeds intake and weight falls even when appetite is increased. Bradycardia, hyporeflexia, and cold intolerance are features of hypothyroidism rather than hyperthyroidism.

Question 7Body System Interactions

Which electrolyte pattern is most characteristic of primary adrenal insufficiency?

  1. Hyponatremia with hyperkalemia Correct answer.
  2. Hypernatremia with hypokalemia
  3. Hyponatremia with hypokalemia
  4. Hypernatremia with hyperkalemia

Explanation

Loss of aldosterone reduces renal sodium reabsorption and potassium secretion, producing sodium wasting, hyponatremia, hyperkalemia, and volume depletion with hypotension. Cortisol deficiency also impairs free-water clearance, which adds to the hyponatremia.

Question 8Body System Interactions

A patient with chronic kidney disease has a pH of 7.28, bicarbonate of 16 mEq/L, and PaCO2 of 34 mm Hg. Which respiratory response is expected as compensation?

  1. Hyperventilation to increase PaCO2
  2. Hypoventilation to retain carbon dioxide
  3. No respiratory change because the disorder is metabolic
  4. Hyperventilation to lower PaCO2 Correct answer.

Explanation

Metabolic acidosis stimulates peripheral chemoreceptors and increases minute ventilation, so PaCO2 falls and pH moves back toward normal. This compensatory hyperventilation produces the Kussmaul breathing pattern.

Question 9Body System Interactions

A patient's oxygen consumption is 1000 mL/min and the arterial-venous oxygen difference is 100 mL/L. What is the cardiac output?

  1. 8 L/min
  2. 10 L/min Correct answer.
  3. 5 L/min
  4. 20 L/min

Explanation

The Fick principle states that oxygen consumption equals cardiac output multiplied by the arteriovenous oxygen difference, so cardiac output equals oxygen consumption divided by that difference. Here 1000 mL/min divided by 100 mL/L gives 10 L/min.

Question 10Body System Interactions

Which mechanism best explains exercise-induced hypoxemia in a patient with interstitial lung disease?

  1. Improved ventilation-perfusion matching during increased cardiac output
  2. Reduced alveolar-capillary surface area combined with shortened capillary transit time during exercise Correct answer.
  3. Hypoventilation caused by respiratory muscle fatigue at low workloads
  4. Right-to-left shunting through a patent foramen ovale

Explanation

Fibrotic remodeling thickens and destroys the alveolar-capillary membrane, so diffusion is already limited at rest. When exercise raises cardiac output and shortens capillary transit time, red cells may pass before full equilibration, and PaO2 falls.

Question 11Body System Interactions

A patient with a complete T4 spinal cord injury develops a pounding headache, profuse sweating above the lesion, blood pressure of 200/110 mm Hg, and a heart rate of 52 beats/min during catheterization. Which mechanism explains these findings?

  1. Loss of sympathetic tone below the lesion causing vasodilation
  2. Increased vagal tone from a primary cardiac arrhythmia
  3. Decreased afferent input from the bladder
  4. Uninhibited sympathetic outflow below the lesion with baroreceptor-mediated bradycardia Correct answer.

Explanation

Noxious input such as bladder distension enters below the lesion and triggers a reflex sympathetic discharge that supraspinal centers cannot modulate, producing severe vasoconstriction and hypertension. Carotid baroreceptors then drive vagal bradycardia; this is autonomic dysreflexia and requires prompt removal of the stimulus.

Question 12Body System Interactions

Why does myocardial ischemia often produce pain in the left shoulder and medial arm?

  1. Referred pain from the pericardium through the phrenic nerve
  2. Sympathetic vasoconstriction of the upper extremity arteries
  3. Compression of the brachial plexus by the ischemic heart
  4. Convergence of cardiac visceral afferents and somatic afferents on shared spinal segments Correct answer.

Explanation

Cardiac visceral afferents enter the spinal cord at approximately C8 through T4, the same segments that receive somatic input from the shoulder and arm. Second-order neurons cannot distinguish the source, so the brain projects the sensation onto the somatic dermatomes.

Question 13Body System Interactions

A patient with persistent vomiting has a pH of 7.50, bicarbonate of 34 mEq/L, hypokalemia, and hypochloremia. Which mechanism contributes most to the alkalosis?

  1. Accumulation of lactic acid from hypoperfusion
  2. Primary hyperaldosteronism
  3. Excessive ingestion of bicarbonate antacids
  4. Loss of gastric hydrogen and chloride with volume depletion causing renal potassium and hydrogen loss Correct answer.

Explanation

Vomiting removes hydrogen and chloride, generating bicarbonate and producing a hypochloremic contraction alkalosis. Volume depletion activates aldosterone, so the kidney reabsorbs sodium in exchange for potassium and hydrogen, sustaining the alkalosis until saline and potassium are replaced.

Question 14Body System Interactions

Which combination most directly promotes ascites in cirrhosis?

  1. Increased lymphatic return with elevated serum albumin
  2. High systemic vascular resistance with hyperalbuminemia
  3. Portal hypertension with reduced plasma oncotic pressure Correct answer.
  4. Reduced splanchnic blood flow with increased colloid osmotic pressure

Explanation

Hepatic fibrosis raises portal pressure while impaired albumin synthesis lowers plasma oncotic pressure, and these Starling forces drive fluid into the peritoneal cavity. Splanchnic vasodilation with renin-angiotensin-aldosterone activation further retains sodium and water.

Question 15Body System Interactions

Which finding best supports a venous rather than an arterial cause of a lower extremity ulcer?

  1. Ulcer near the medial malleolus with edema and hemosiderin staining Correct answer.
  2. Severe nighttime pain relieved by hanging the leg over the bed
  3. Ulcer on the tip of the toe with dependent rubor
  4. Punched-out ulcer with a pale base and absent pedal pulses

Explanation

Chronic venous hypertension produces edema, red-brown hemosiderin deposition, and ulcers typically near the medial malleolus, with palpable pulses and relief on elevation. Arterial ulcers are distal, painful at rest, and associated with absent pulses and dependent rubor.

Question 16Body System Interactions

Which immune change is most consistent with the period immediately after a prolonged high-intensity endurance event?

  1. Permanent depletion of circulating neutrophils
  2. Transient decrease in salivary immunoglobulin A with increased upper respiratory symptom risk Correct answer.
  3. Enhanced delayed hypersensitivity with reduced infection risk
  4. Persistent increase in mucosal immunoglobulin A

Explanation

Prolonged strenuous exercise transiently lowers mucosal immunoglobulin A and impairs neutrophil function while stress hormones rise, creating a window of increased infection susceptibility. Moderate exercise, by contrast, tends to enhance immune surveillance.

Question 17Body System Interactions

At 32 weeks of gestation, a patient becomes dizzy, diaphoretic, and hypotensive when lying supine. Which mechanism best explains this?

  1. Acute placental abruption causing hemorrhage
  2. Aortic compression above the diaphragm reducing left ventricular output
  3. Increased vagal tone from fetal movement
  4. Compression of the inferior vena cava by the gravid uterus reducing venous return Correct answer.

Explanation

The gravid uterus compresses the inferior vena cava in the supine position, dropping preload and cardiac output and producing hypotension with vagal symptoms. Turning to the left lateral position relieves the compression.

Question 18Body System Interactions

Which age-related vascular change most directly explains an elevated systolic pressure with a normal or low diastolic pressure?

  1. Increased stiffness of the large arteries Correct answer.
  2. Decreased left ventricular ejection fraction
  3. Reduced peripheral vascular resistance
  4. Increased blood viscosity

Explanation

Arterial stiffening raises pulse wave velocity so the reflected wave returns during systole, augmenting systolic and pulse pressure while diastolic pressure falls. This produces the isolated systolic hypertension typical of older adults.

Question 19Body System Interactions

Which pulmonary change most contributes to hypoxemia in a patient with severe obesity when supine?

  1. Increased total lung capacity with hyperinflation
  2. Increased chest wall compliance
  3. Reduced functional residual capacity with dependent airway closure Correct answer.
  4. Elevated residual volume with air trapping

Explanation

Abdominal and chest wall mass reduce functional residual capacity, and in the supine position the diaphragm is displaced cephalad, so dependent lung units fall below closing volume and shunt. The result is ventilation-perfusion mismatch and hypoxemia.

Question 20Body System Interactions

Which sequence best explains worsening edema in decompensated heart failure?

  1. Reduced cardiac output activating the renin-angiotensin-aldosterone system and ADH, causing sodium and water retention Correct answer.
  2. Increased glomerular filtration rate with reduced aldosterone
  3. Increased cardiac output leading to renal sodium excretion
  4. Reduced sympathetic outflow with decreased peripheral resistance

Explanation

When forward output falls, renal perfusion and tubular sodium delivery drop, so renin-angiotensin-aldosterone and ADH activation retain sodium and water. Rising venous pressure simultaneously increases capillary hydrostatic pressure, producing edema.

Question 21Body System Interactions

Why does a single session of aerobic exercise improve blood glucose for hours in a patient with type 2 diabetes?

  1. It decreases hepatic glucose output to zero
  2. It increases pancreatic insulin secretion for the rest of the day
  3. It reduces muscle GLUT4 expression to limit glucose entry
  4. It stimulates insulin-independent translocation of GLUT4 in contracting muscle Correct answer.

Explanation

Muscle contraction activates signaling pathways that move GLUT4 to the sarcolemma, so glucose uptake rises even without insulin, and the effect persists after exercise as insulin sensitivity improves. This is why post-exercise glucose control improves independently of insulin secretion.

Question 22Body System Interactions

Which electrocardiographic change is most expected with a serum potassium of 6.8 mEq/L?

  1. Peaked T waves progressing to a widened QRS Correct answer.
  2. Prolonged QT interval with torsades de pointes
  3. Prominent U waves with a flattened T wave
  4. Diffuse ST elevation with PR depression

Explanation

Hyperkalemia accelerates repolarization, producing tall, narrow, peaked T waves; as potassium rises further, conduction slows with PR prolongation and QRS widening. U waves and QT prolongation are features of hypokalemia.

Question 23Body System Interactions

Which finding best indicates right ventricular failure from cor pulmonale?

  1. Inspiratory stridor with a normal jugular venous pressure
  2. Elevated jugular venous pressure with peripheral edema Correct answer.
  3. Bounding pulses with warm extremities
  4. Bibasilar crackles with orthopnea

Explanation

Chronic pulmonary hypertension loads the right ventricle, so systemic venous pressure rises and appears as jugular venous distension, hepatomegaly, and dependent peripheral edema. Pulmonary crackles and orthopnea instead reflect left-sided failure.

Question 24Body System Interactions

Which mechanism best explains cardiovascular drift during prolonged exercise in the heat?

  1. A progressive increase in plasma volume
  2. Plasma volume loss and cutaneous blood flow redistribution reducing stroke volume, requiring a higher heart rate Correct answer.
  3. A decrease in core temperature with increased vagal tone
  4. Reduced sweat rate with falling skin blood flow

Explanation

Sweating and fluid shifts reduce plasma volume while skin vasodilation diverts blood to the periphery, so venous return and stroke volume fall. Heart rate rises to maintain cardiac output at a constant workload, and core temperature climbs, which is why drift is greater in heat and with dehydration.

Question 25Body System Interactions

During a sustained isometric handgrip, which mechanism most increases mean arterial pressure?

  1. Withdrawal of sympathetic outflow to the splanchnic bed
  2. Metaboreflex-driven sympathetic vasoconstriction with increased cardiac output Correct answer.
  3. Baroreceptor-mediated vasodilation in the contracting muscle
  4. Reduced left ventricular afterload from local vasodilation

Explanation

Metabolites accumulate in the contracting muscle and stimulate group III and IV afferents, raising sympathetic outflow. Vasoconstriction in nonexercising beds plus increased cardiac output elevate blood pressure, and the response is amplified if a Valsalva maneuver is added.

Question 26Body System Interactions

A patient with severe iron-deficiency anemia has a hemoglobin of 7 g/dL, a resting cardiac output of 7.4 L/min, and a systemic vascular resistance below normal. Which mechanism best explains these hemodynamic findings?

  1. Reduced arterial oxygen content lowers systemic vascular resistance and drives a compensatory rise in output. Correct answer.
  2. Depressed myocardial contractility causes ventricular dilation, which increases stroke volume and output.
  3. Increased blood viscosity from iron deficiency raises vascular resistance and forces the heart to work harder.
  4. Sodium and water retention by the kidneys expands plasma volume, and this alone accounts for the elevated output.

Explanation

When arterial oxygen content falls, tissues extract more oxygen per unit of blood, and the resulting vasodilation of peripheral and microvascular beds lowers systemic vascular resistance. The baroreflex-mediated rise in sympathetic tone and the reduction in afterload both raise cardiac output, producing a hyperdynamic, high-output state. Viscosity is reduced, not increased, in iron deficiency.

Question 27Body System Interactions

A patient with severe COPD forcefully exhales against a closed glottis while moving in bed and becomes acutely hypotensive. Which mechanism best explains the fall in blood pressure?

  1. Elevated intrathoracic pressure reduces venous return, lowering stroke volume and cardiac output. Correct answer.
  2. Increased intrathoracic pressure compresses the aorta and raises left ventricular afterload, causing reflex bradycardia.
  3. Forceful expiration triggers vagal discharge that directly depresses myocardial contractility.
  4. Expiratory effort raises pulmonary vascular resistance, shunting blood into the systemic circuit and raising pressure.

Explanation

A forced expiration against a closed glottis raises intrathoracic pressure, which is transmitted to the great veins and right atrium and impedes venous return. The drop in preload reduces right ventricular output, then left ventricular filling, and cardiac output falls faster than reflex vasoconstriction can compensate, so blood pressure drops.

Question 28Body System Interactions

A patient with a 20-year history of type 1 diabetes reports dizziness on standing. On testing, systolic pressure falls 25 mm Hg with no compensatory rise in heart rate. Which mechanism best explains this finding?

  1. Increased resting vagal tone producing vasodilation and a blunted heart rate response
  2. Damage to efferent sympathetic vasoconstrictor and cardiac accelerator fibers from diabetic neuropathy Correct answer.
  3. Impaired baroreceptor afferent signaling caused by carotid atherosclerosis
  4. Intravascular volume depletion from chronic hyperglycemia-induced osmotic diuresis

Explanation

Orthostatic hypotension without tachycardia points to an efferent limb failure rather than a volume or afferent problem, because the reflex arc cannot generate either vasoconstriction or cardioacceleration. Diabetic autonomic neuropathy damages the efferent sympathetic fibers serving both vascular tone and the sinoatrial node. Volume depletion and afferent baroreceptor lesions typically preserve the tachycardic response.

Question 29Body System Interactions

A patient with severe COPD and dynamic hyperinflation is placed supine and becomes hypotensive. Which mechanism best explains the drop in blood pressure?

  1. Air trapping increases pulmonary capillary wedge pressure, which reduces left ventricular filling.
  2. Hypoxemia from air trapping triggers systemic vasodilation and lowers mean arterial pressure.
  3. Elevated intrathoracic pressure from trapped gas reduces venous return to the right heart. Correct answer.
  4. Hyperinflation stretches the pericardium and limits right atrial filling through direct compression.

Explanation

Dynamic hyperinflation produces intrinsic positive end-expiratory pressure, and that positive alveolar pressure is transmitted to the intrathoracic veins and right atrium. The resulting fall in venous return reduces right ventricular filling, and the septum shifts and left ventricular filling is impaired, lowering cardiac output and blood pressure.

Question 30Body System Interactions

A patient has hypertension, a serum potassium of 3.1 mEq/L, and an elevated aldosterone-to-renin ratio. Which mechanism best explains these findings?

  1. Aldosterone increases renal potassium reabsorption and sodium excretion, depleting plasma volume.
  2. Aldosterone increases renal sodium reabsorption and potassium excretion, expanding plasma volume. Correct answer.
  3. Excess renin raises systemic vascular resistance directly, independent of aldosterone.
  4. Cortisol excess activates mineralocorticoid receptors once concentrations become very high.

Explanation

Aldosterone acts on the distal nephron to increase sodium reabsorption in exchange for potassium and hydrogen excretion. The retained sodium expands extracellular volume and raises blood pressure, while urinary potassium losses produce hypokalemia. A high aldosterone with suppressed renin indicates autonomous aldosterone production rather than a renin-driven process.

Question 31Body System Interactions

A patient develops confusion and a serum sodium of 122 mEq/L after a stroke, with concentrated urine and normal volume status. Which mechanism best explains the hyponatremia?

  1. Reduced aldosterone secretion causes renal sodium wasting and progressive volume depletion
  2. Renal sodium loss driven by elevated atrial natriuretic peptide released after the stroke
  3. Excess antidiuretic hormone increases free water retention, which dilutes the serum sodium Correct answer.
  4. Hypothalamic injury increases thirst, so water intake rises without any change in solute handling

Explanation

Inappropriate antidiuretic hormone secretion increases water permeability in the collecting duct, so ingested and infused water is retained without proportional sodium. The expansion of total body water relative to sodium lowers the serum sodium concentration and produces hypo-osmolality, with concentrated urine that is inappropriately high for the low serum osmolality.

Question 32Body System Interactions

A patient with a large pulmonary embolus is hypoxemic but has a normal or low arterial PaCO2. Which mechanism best accounts for this pattern?

  1. Hyperventilation reduces whole-body oxygen consumption, so arterial oxygen rises toward normal.
  2. Loss of surfactant decreases lung compliance, producing widespread alveolar collapse and shunt.
  3. Increased blood flow through well-ventilated units produces a diffusion limitation for oxygen.
  4. Occluded vessels create dead space, and overventilation of perfused units lowers PaCO2. Correct answer.

Explanation

Obstructed pulmonary arteries eliminate perfusion to ventilated alveolar units, creating dead space, while blood is diverted to remaining units and overwhelms their ventilation-perfusion matching. Chemoreceptor stimulation from hypoxemia drives hyperventilation, which clears carbon dioxide efficiently from the still-perfused units and lowers PaCO2 even though oxygen transfer remains impaired.

Question 33Body System Interactions

A patient with a blood glucose of 50 mg/dL presents with tremor, palpitations, and diaphoresis. Which mechanism best explains these symptoms?

  1. Sympathoadrenal epinephrine release causes tremor, tachycardia, and diaphoresis. Correct answer.
  2. Cortisol release produces immediate vasoconstriction and skeletal muscle tremor.
  3. Glucagon release directly stimulates sweat glands and skeletal muscle tremor.
  4. Parasympathetic activation increases gut motility and stimulates the sweat glands.

Explanation

Falling glucose is sensed centrally and triggers sympathoadrenal discharge, and epinephrine produces the classic adrenergic warning symptoms of tremor, palpitations, and diaphoresis. These symptoms appear at a higher glucose threshold than neuroglycopenic symptoms such as confusion, which occur as glucose falls further.

Question 34Body System Interactions

Which mechanism best explains the development of daytime hypertension in a patient with obstructive sleep apnea?

  1. Nocturnal hypercapnia directly stimulates the carotid bodies to lower blood pressure.
  2. Chronic hyperventilation during apneic events increases cardiac output and systemic pressure.
  3. Recurrent nocturnal hypoxemia and arousals increase sympathetic outflow and raise vascular tone. Correct answer.
  4. Reduced intrathoracic pressure during obstructive events increases pulmonary venous return and left heart output.

Explanation

Each obstructive event produces hypoxemia, hypercapnia, and an arousal, all of which increase sympathetic neural outflow and circulating catecholamines. Repeated nightly exposure sustains elevated peripheral vascular tone and blunts nocturnal blood pressure dipping, so hypertension persists into the daytime.

Question 35Body System Interactions

A patient with sepsis has a blood pressure of 88/52 mm Hg, warm extremities, and a lactate of 4 mmol/L. Which mechanism best explains the hypotension?

  1. Widespread vasodilation with maldistribution of blood flow and anaerobic metabolism Correct answer.
  2. Volume overload from acute kidney injury with an elevated central venous pressure
  3. Increased systemic vascular resistance combined with a reduced cardiac output
  4. Primary myocardial depression from acute infarction with elevated filling pressures

Explanation

Inflammatory mediators cause nitric oxide-mediated vasodilation and capillary leak, so systemic vascular resistance falls and pressure drops despite a normal or high cardiac output. Microvascular shunting impairs oxygen delivery to some beds, producing anaerobic metabolism and a rising lactate with warm, well-perfused extremities.

Question 36Body System Interactions

Twelve hours after a 40% total body surface area burn, a patient has hypotension, tachycardia, and hemoconcentration. Which mechanism best explains these findings?

  1. Increased capillary hydrostatic pressure from aggressive fluid resuscitation drives protein-poor fluid into the interstitium.
  2. Widespread capillary leak shifts plasma protein and water into the interstitium, reducing blood volume. Correct answer.
  3. A vasovagal response to pain lowers heart rate and peripheral vascular resistance.
  4. Reduced oncotic pressure from hepatic failure causes fluid to shift into the interstitial space.

Explanation

Thermal injury produces a systemic inflammatory response that increases capillary permeability well beyond the burn wound, so protein and water move into the interstitium. Loss of intravascular volume lowers preload and blood pressure, while hemoconcentration reflects the shift of plasma out of the vessels. Compensatory tachycardia maintains cardiac output.

Question 37Body System Interactions

Which mechanism best explains fasting hypoglycemia in a patient with fulminant hepatic failure?

  1. Impaired hepatic glycogenolysis and gluconeogenesis reduce glucose production Correct answer.
  2. Enhanced renal glucose excretion from acute tubular damage
  3. Increased insulin secretion from direct pancreatic injury
  4. Reduced cortisol clearance producing increased insulin sensitivity

Explanation

The liver maintains blood glucose during fasting through glycogen breakdown and, once glycogen stores are depleted, through gluconeogenesis. When hepatic function fails, both processes are impaired, so glucose production cannot match ongoing peripheral use and fasting hypoglycemia develops.

Question 38Body System Interactions

A patient with long-standing hypertension has a baseline blood pressure of 170/95 mm Hg. Which statement best describes cerebral blood flow regulation in this patient?

  1. The autoregulatory curve shifts upward, so pressures that are normal for others may cause hypoperfusion. Correct answer.
  2. Autoregulation is abolished entirely, so cerebral flow varies passively with pressure across all ranges.
  3. The curve shifts downward, protecting the brain from hypertensive injury at lower pressures.
  4. Cerebral resistance vessels remain maximally dilated, so flow is fixed regardless of pressure.

Explanation

Chronic hypertension causes hypertrophic remodeling of cerebral arterioles, resetting the autoregulatory range to higher pressures so that the lower and upper limits both rise. Because of this upward shift, a blood pressure that is normal for the general population may fall below the patient's lower limit and produce cerebral hypoperfusion and symptoms.

Question 39Body System Interactions

Which mechanism best explains the high cardiac output and low systemic vascular resistance in a patient with decompensated cirrhosis?

  1. Splanchnic vasodilation from nitric oxide lowers resistance and triggers a compensatory rise in cardiac output. Correct answer.
  2. Portal hypertension directly increases left ventricular afterload and causes secondary ventricular dilation.
  3. Reduced hepatic clearance of circulating catecholamines produces sustained systemic vasoconstriction with increased output.
  4. Increased blood viscosity from elevated erythropoietin raises venous return and cardiac output.

Explanation

Portal hypertension stimulates local production of nitric oxide and other vasodilators, so the splanchnic circulation becomes a large low-resistance bed and effective arterial volume falls. Baroreceptor-mediated activation of the renin-angiotensin-aldosterone and sympathetic systems raises heart rate and output in compensation, producing the hyperdynamic circulation of cirrhosis.

Question 40Body System Interactions

Which mechanism best explains the normocytic anemia in a patient with stage 5 chronic kidney disease?

  1. Iron malabsorption from uremic gastritis is the dominant cause
  2. Reduced erythropoietin production by damaged peritubular fibroblasts Correct answer.
  3. Splenic sequestration of red blood cells induced by progressive uremia
  4. Chronic blood loss during dialysis treatments is the sole cause

Explanation

Erythropoietin is produced mainly by peritubular interstitial fibroblasts in the renal cortex, and loss of functioning renal mass reduces its secretion. Without adequate erythropoietin signaling, erythroid progenitors in the marrow survive and differentiate poorly, producing a normocytic, normochromic anemia.

Question 41Non-Systems: Safety and Protection, Professional Responsibilities, Research

Which action is required before and after contact with every patient, regardless of the patient's diagnosis?

  1. Donning a lead apron
  2. Wearing sterile gloves
  3. Performing hand hygiene Correct answer.
  4. Applying a surgical mask

Explanation

Standard precautions are applied to all patients at all times, and hand hygiene before and after contact is the core element of that practice. Gloves supplement but never replace hand hygiene.

Question 42Non-Systems: Safety and Protection, Professional Responsibilities, Research

A confused patient with a history of falls is admitted to a rehabilitation unit. Which intervention is most appropriate for reducing fall risk?

  1. Applying a vest restraint whenever the patient is in bed
  2. Raising all four side rails whenever the patient is alone
  3. Bed in lowest position with call light in reach Correct answer.
  4. Assigning a room located far from the nurses' station

Explanation

Environmental modification, including a low bed and easily reachable call light, is a first-line fall-prevention strategy that reduces injury risk without restricting the patient. Restrictive devices are reserved for narrowly defined situations and require specific orders.

Question 43Non-Systems: Safety and Protection, Professional Responsibilities, Research

Which technique best protects a therapist's lumbar spine when lifting a heavy object from the floor?

  1. Twisting the trunk while lifting to shorten the distance
  2. Holding the load away from the body to improve leverage
  3. Bending the knees and holding the load close Correct answer.
  4. Using a fast, jerking motion to overcome inertia

Explanation

Bending the knees and keeping the load near the body shortens the moment arm and allows the stronger lower-extremity muscles to do the work. This reduces compressive and shear loads on the lumbar spine.

Question 44Non-Systems: Safety and Protection, Professional Responsibilities, Research

A fire starts in a patient care area. According to the RACE sequence, which action should be taken first?

  1. Extinguish the flames with the nearest extinguisher
  2. Activate the fire alarm pull station
  3. Move patients out of immediate danger Correct answer.
  4. Close all corridor doors to contain smoke

Explanation

RACE stands for Rescue, Alarm, Contain, Extinguish, so removing anyone in immediate danger comes before alarming, containing, or extinguishing. Life safety of occupants always precedes property protection.

Question 45Non-Systems: Safety and Protection, Professional Responsibilities, Research

A therapist finds a frayed power cord on an electrical stimulation unit before a treatment session. What is the most appropriate action?

  1. Wrap the cord in tape and continue the treatment
  2. Use the device only at the lowest intensity setting
  3. Remove the device from service and tag it Correct answer.
  4. Plug the device into an extension cord and proceed

Explanation

Damaged cords create a shock and fire hazard and must be taken out of service immediately and labeled so others do not use it. Repair must be completed by qualified personnel before the device returns to use.

Question 46Non-Systems: Safety and Protection, Professional Responsibilities, Research

Which instruction is most important to give a patient who is starting to use home oxygen therapy?

  1. Store the cylinder in a closed car trunk while traveling
  2. Keep the oxygen delivery equipment away from open flames Correct answer.
  3. Apply petroleum jelly to the nares to prevent dryness
  4. Adjust the flow rate yourself if you feel short of breath

Explanation

Oxygen supports combustion, so the equipment must be kept away from open flames, sparks, and heat sources. Patients and household members should also be advised not to smoke in the presence of the equipment.

Question 47Non-Systems: Safety and Protection, Professional Responsibilities, Research

A therapist sustains a needlestick injury from a contaminated needle while working in an inpatient setting. What should the therapist do first?

  1. Apply a tight tourniquet above the puncture site
  2. Report the exposure to the supervisor at the end of the shift
  3. Request the source patient's HIV status before taking action
  4. Wash the site with soap and water and report immediately Correct answer.

Explanation

Immediate washing of the exposed site followed by prompt reporting allows the exposure to be evaluated and post-exposure prophylaxis to be started within the window when it is effective. Delaying evaluation compromises the effectiveness of prophylaxis.

Question 48Non-Systems: Safety and Protection, Professional Responsibilities, Research

A patient's employer calls and asks whether the patient can return to work with a 50-lb lifting requirement. What is the most appropriate response?

  1. Confirm the patient's diagnosis and prognosis by phone
  2. Release only authorized work restrictions Correct answer.
  3. Provide the employer with the complete evaluation
  4. Decline to speak with the employer at any time

Explanation

Confidentiality rules permit disclosure of only the minimum information necessary, and disclosure of work restrictions requires the patient's authorization. The diagnosis and clinical details are not shared with an employer without that authorization.

Question 49Non-Systems: Safety and Protection, Professional Responsibilities, Research

Which element is essential for valid informed consent to treatment?

  1. A verbal agreement that is undocumented
  2. A signature witnessed by a patient
  3. Approval given by the patient's spouse
  4. Voluntary consent after risks are disclosed Correct answer.

Explanation

Valid consent requires that the patient receive information about the nature of the intervention, its risks, benefits, and alternatives, and then agree voluntarily. The patient must also have the capacity to make the decision.

Question 50Non-Systems: Safety and Protection, Professional Responsibilities, Research

Which task is appropriate for a physical therapist to delegate to a physical therapist assistant?

  1. Determining the patient's discharge destination
  2. Implementing interventions in the established plan of care Correct answer.
  3. Performing the initial examination and developing the plan of care
  4. Interpreting the results of a standardized balance test

Explanation

The physical therapist retains responsibility for examination, evaluation, diagnosis, prognosis, and the plan of care, while the assistant may implement selected interventions and progress them within that plan. The therapist must be available for consultation as required by jurisdiction.