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Question 1Pathophysiology and management of kidney disease

Which laboratory value is used to classify the stage of chronic kidney disease?

  1. Serum potassium level
  2. Glomerular filtration rate Correct answer.
  3. Urine specific gravity
  4. Serum albumin concentration

Explanation

CKD is staged by the estimated glomerular filtration rate, with stages 1 through 5 defined by descending GFR ranges. Albuminuria is used as a modifier within each stage but does not replace GFR for staging.

Question 2Pathophysiology and management of kidney disease

The anemia of chronic kidney disease results mainly from inadequate production of which hormone?

  1. Renin release
  2. Erythropoietin Correct answer.
  3. Calcitriol synthesis
  4. Aldosterone secretion

Explanation

Peritubular interstitial cells of the kidney produce erythropoietin, which stimulates erythroid progenitors in the marrow. Loss of functioning renal mass reduces erythropoietin output and produces a normocytic, normochromic anemia.

Question 3Pathophysiology and management of kidney disease

Which pattern of findings is characteristic of nephrotic syndrome?

  1. Sterile pyuria with flank pain
  2. Red blood cell casts in the urine
  3. Proteinuria with hypoalbuminemia Correct answer.
  4. Hypertension with oliguria

Explanation

Nephrotic syndrome reflects glomerular injury that permits loss of albumin and other proteins, producing heavy proteinuria, hypoalbuminemia, edema, and hyperlipidemia. It is generally a non-inflammatory, non-proliferative pattern of injury.

Question 4Pathophysiology and management of kidney disease

Which condition is the most common cause of chronic kidney disease in the United States?

  1. Polycystic kidney disease
  2. Glomerulonephritis
  3. Diabetes mellitus Correct answer.
  4. Hypertensive nephrosclerosis

Explanation

Diabetic nephropathy accounts for the largest share of patients reaching end-stage kidney disease in the United States, followed by hypertension. Glomerulonephritis and cystic disease are less frequent causes.

Question 5Pathophysiology and management of kidney disease

Which finding is a recognized manifestation of the uremic syndrome?

  1. Metabolic alkalosis
  2. Pericarditis Correct answer.
  3. Hypercalcemia
  4. Polyuria with dilute urine

Explanation

Retention of nitrogenous waste and inflammatory mediators in advanced kidney failure can inflame the pericardium, producing a friction rub and effusion. Uremic pericarditis is an indication to intensify or initiate dialysis.

Question 6Pathophysiology and management of kidney disease

A patient is prescribed calcium acetate as a phosphate binder. When should the medication be taken?

  1. Every 8 hours regardless of food
  2. One hour before breakfast
  3. With meals Correct answer.
  4. At bedtime

Explanation

Phosphate binders must be present in the gut lumen at the same time as dietary phosphate to form insoluble complexes. Dosing with meals or snacks maximizes binding and limits absorption of phosphate.

Question 7Pathophysiology and management of kidney disease

Which finding in a patient on peritoneal dialysis most suggests peritonitis?

  1. Reduced ultrafiltration volume
  2. Fibrin strands in clear fluid
  3. Bloody dialysate return
  4. Cloudy dialysate effluent Correct answer.

Explanation

Cloudy effluent reflects an influx of leukocytes into the peritoneal cavity and is the cardinal sign of peritonitis. It is typically accompanied by abdominal pain and fever and warrants culture and prompt antibiotic therapy.

Question 8Pathophysiology and management of kidney disease

Which renal finding is characteristic of autosomal dominant polycystic kidney disease?

  1. Progression to end-stage disease in childhood
  2. Bilateral small scarred kidneys
  3. Multiple bilateral renal cysts Correct answer.
  4. Isolated hematuria without cysts

Explanation

ADPKD produces progressive enlargement of both kidneys by numerous cysts, often with hematuria, flank pain, hypertension, and eventual kidney failure in adulthood. It is the most common inherited kidney disorder.

Question 9Pathophysiology and management of kidney disease

Which acid-base pattern is typical of early to moderate chronic kidney disease?

  1. Respiratory alkalosis with renal compensation
  2. Normal anion gap metabolic acidosis Correct answer.
  3. High anion gap respiratory alkalosis
  4. Mixed metabolic and respiratory alkalosis

Explanation

Reduced ammoniagenesis and impaired hydrogen ion excretion in moderate CKD produce a hyperchloremic, normal anion gap metabolic acidosis. As failure advances, retained unmeasured anions widen the anion gap.

Question 10Pathophysiology and management of kidney disease

A patient with CKD has a serum potassium of 6.8 mEq/L with peaked T waves. Which listed medication shifts potassium into cells most rapidly?

  1. IV insulin with dextrose Correct answer.
  2. Oral sodium polystyrene sulfonate
  3. Oral calcium carbonate
  4. IV furosemide

Explanation

Insulin drives potassium into skeletal muscle and liver cells within minutes, making it the fastest intracellular shift among the listed options. It is given with dextrose to prevent hypoglycemia.

Question 11Pathophysiology and management of kidney disease

A fractional excretion of sodium below 1% in a patient with acute kidney injury suggests which cause?

  1. Acute tubular necrosis
  2. Acute interstitial nephritis
  3. Postrenal obstruction
  4. Volume depletion Correct answer.

Explanation

In a prerenal state, intact tubules avidly reabsorb sodium and water, so the fraction of filtered sodium excreted falls below 1%. A value above 2% suggests intrinsic tubular injury such as acute tubular necrosis.

Question 12Pathophysiology and management of kidney disease

Which urinary finding is most consistent with acute tubular necrosis?

  1. Red blood cell casts
  2. White blood cell casts
  3. Broad waxy casts
  4. Muddy brown granular casts Correct answer.

Explanation

Necrotic tubular epithelial cells slough into the lumen and form the pigmented granular casts classically seen in acute tubular necrosis. Their presence supports an intrinsic rather than prerenal or postrenal cause.

Question 13Pathophysiology and management of kidney disease

Which measure best reduces the risk of contrast-induced acute kidney injury in a patient with CKD?

  1. High-dose mannitol infusion
  2. Oral NSAIDs for pain control
  3. Saline volume expansion Correct answer.
  4. Furosemide before the study

Explanation

Intravascular volume expansion with isotonic saline maintains renal perfusion and dilutes the contrast load, and it is the mainstay of prevention. Minimizing contrast volume is also important.

Question 14Pathophysiology and management of kidney disease

Which finding is the earliest clinical marker of diabetic nephropathy?

  1. Microalbuminuria Correct answer.
  2. Macroalbuminuria
  3. Elevated serum creatinine
  4. Reduced eGFR below 60

Explanation

Small amounts of albumin leak through the glomerulus before the filtration rate declines, so persistent microalbuminuria is the earliest detectable marker. Intervention at this stage can slow progression.

Question 15Pathophysiology and management of kidney disease

Which antihypertensive class is preferred for a patient with CKD and proteinuria?

  1. Loop diuretics
  2. ACE inhibitors Correct answer.
  3. Alpha blockers
  4. Thiazide diuretics

Explanation

ACE inhibitors lower intraglomerular pressure by dilating the efferent arteriole and reduce proteinuria, slowing progression of kidney disease. Serum creatinine and potassium require monitoring after initiation.

Question 16Pathophysiology and management of kidney disease

Which finding is an accepted indication for emergent dialysis?

  1. Serum creatinine 5 mg/dL
  2. Refractory pulmonary edema Correct answer.
  3. Blood urea nitrogen 60 mg/dL
  4. Oliguria for 12 hours

Explanation

Dialysis is indicated for solute or volume problems that cannot be controlled medically, such as fluid overload refractory to diuretics. Absolute numbers for creatinine or BUN alone do not mandate emergent treatment.

Question 17Pathophysiology and management of kidney disease

Which parameter is used to quantify the adequacy of a hemodialysis treatment?

  1. Kt/V urea Correct answer.
  2. Hemoglobin A1c
  3. Serum albumin
  4. Creatinine clearance

Explanation

Kt/V urea incorporates dialyzer clearance, treatment time, and urea distribution volume to express the fraction of urea removed. A minimum delivered value is targeted to ensure adequate small-solute clearance.

Question 18Pathophysiology and management of kidney disease

Which assessment finding indicates that an arteriovenous fistula is mature and functioning?

  1. Absent thrill with a palpable pulse
  2. Bleeding from prior needle sites
  3. Palpable thrill and bruit Correct answer.
  4. Cool skin over the access

Explanation

A mature fistula transmits arterial pressure into the venous limb, producing a palpable thrill and an audible bruit from turbulent flow. These findings confirm patency and adequate development of the outflow vein.

Question 19Pathophysiology and management of kidney disease

A patient develops headache, confusion, and a seizure shortly after the first hemodialysis session. Which complication is most likely?

  1. Hypernatremia
  2. Hypoglycemia
  3. Disequilibrium syndrome Correct answer.
  4. Air embolism

Explanation

Rapid removal of urea from plasma creates an osmotic gradient that draws water into brain cells, producing cerebral edema. Symptoms range from headache and nausea to confusion and seizures, and prevention relies on slower initial treatments.

Question 20Pathophysiology and management of kidney disease

Secondary hyperparathyroidism in chronic kidney disease is driven primarily by which combination of abnormalities?

  1. Hyperkalemia with acidosis
  2. High calcium and high phosphate
  3. Low PTH with high calcitriol
  4. Hypocalcemia and hyperphosphatemia Correct answer.

Explanation

Falling calcitriol production and phosphate retention lower serum ionized calcium and stimulate parathyroid hormone release. Chronic stimulation leads to parathyroid hyperplasia and renal osteodystrophy.

Question 21Pathophysiology and management of kidney disease

Which type of renal allograft rejection is caused by preformed donor-specific antibodies and occurs within minutes to hours after reperfusion?

  1. Acute antibody-mediated rejection
  2. Acute cellular rejection
  3. Hyperacute rejection Correct answer.
  4. Chronic allograft nephropathy

Explanation

Preformed antibodies bind graft endothelium and trigger immediate complement activation, thrombosis, and graft necrosis at the time of reperfusion. This is why crossmatching is performed before transplantation.

Question 22Pathophysiology and management of kidney disease

A patient on long-term hemodialysis develops carpal tunnel syndrome, bone cysts, and shoulder pain. Deposition of which protein is responsible?

  1. Amyloid A protein
  2. Beta-2 microglobulin Correct answer.
  3. Immunoglobulin light chains
  4. Transthyretin

Explanation

Beta-2 microglobulin is a middle-molecule solute that conventional low-flux dialysis clears poorly, so it accumulates and deposits as amyloid in joints, bone, and soft tissue. The resulting arthropathy is known as dialysis-related amyloidosis.

Question 23Pathophysiology and management of kidney disease

Which abnormality best explains the bleeding tendency seen in uremia?

  1. Thrombocytopenia
  2. Reduced von Willebrand factor
  3. Impaired platelet function Correct answer.
  4. Deficiency of clotting factors

Explanation

Uremic toxins alter platelet adhesion and aggregation and impair the interaction of platelets with the vessel wall, prolonging the bleeding time despite a normal platelet count. Dialysis and desmopressin improve this defect.

Question 24Pathophysiology and management of kidney disease

A patient with advanced CKD and a BUN of 120 mg/dL develops a pericardial friction rub. What is the most appropriate management?

  1. Intensify dialysis Correct answer.
  2. NSAIDs and observation
  3. Pericardiocentesis
  4. Corticosteroids

Explanation

Uremic pericarditis results from retained nitrogenous waste and resolves with adequate clearance, so initiating or intensifying dialysis is the primary treatment. Pericardiocentesis is reserved for hemodynamically significant tamponade.

Question 25Pathophysiology and management of kidney disease

Why is peritoneal dialysis often preferred for a patient who is hemodynamically unstable?

  1. Higher small-solute clearance
  2. No risk of peritonitis
  3. Gentler continuous fluid removal Correct answer.
  4. No need for peritoneal membrane function

Explanation

Peritoneal dialysis removes fluid and solute slowly and continuously, avoiding the rapid shifts that cause hypotension during intermittent hemodialysis. This makes it better tolerated in patients with cardiac instability.

Question 26Pathophysiology and management of kidney disease

Which kidney stone type is associated with infection by urease-producing bacteria such as Proteus mirabilis?

  1. Uric acid
  2. Cystine
  3. Struvite Correct answer.
  4. Calcium oxalate

Explanation

Urease splits urea into ammonia, alkalinizing the urine and favoring precipitation of magnesium ammonium phosphate (struvite) stones. Calcium oxalate stones are typically metabolic, uric acid stones form in acidic urine, and cystine stones reflect a genetic transport defect.

Question 27Pathophysiology and management of kidney disease

Which condition is the most common cause of nephrotic syndrome in children?

  1. Membranous nephropathy
  2. Minimal change disease Correct answer.
  3. IgA nephropathy
  4. Focal segmental glomerulosclerosis

Explanation

Minimal change disease accounts for most childhood nephrotic syndrome and is usually steroid-responsive. Membranous nephropathy and focal segmental glomerulosclerosis more often cause nephrotic syndrome in adults, while IgA nephropathy typically produces a nephritic picture.

Question 28Pathophysiology and management of kidney disease

Which hormone deficiency is the primary cause of normocytic anemia in chronic kidney disease?

  1. Erythropoietin Correct answer.
  2. Thyroxine
  3. Cortisol
  4. Testosterone

Explanation

Peritubular interstitial cells in the kidney sense hypoxia and produce erythropoietin; loss of renal parenchyma reduces this production. Iron deficiency and inflammation often coexist, but erythropoietin deficiency is the central driver of anemia of CKD.

Question 29Pathophysiology and management of kidney disease

Which urine finding is most suggestive of glomerulonephritis?

  1. Hyaline casts
  2. Red cell casts Correct answer.
  3. Oval fat bodies
  4. Broad waxy casts

Explanation

Red cell casts form when erythrocytes enter tubules from inflamed glomeruli and are a hallmark of nephritic syndrome. Hyaline casts are nonspecific, broad waxy casts indicate chronic stasis, and oval fat bodies reflect nephrotic-range proteinuria.

Question 30Pathophysiology and management of kidney disease

A patient with Sjögren syndrome has a non-anion-gap metabolic acidosis, a urine pH of 6.5, and nephrocalcinosis. Which type of renal tubular acidosis is most likely?

  1. Type 2 proximal renal tubular acidosis
  2. Fanconi syndrome
  3. Type 1 distal renal tubular acidosis Correct answer.
  4. Type 4 hyperkalemic renal tubular acidosis

Explanation

Distal RTA impairs hydrogen ion secretion in the collecting duct, so the urine cannot be maximally acidified despite systemic acidosis; alkaline urine favors calcium phosphate stones and nephrocalcinosis. Proximal RTA causes bicarbonate wasting, and type 4 RTA is characterized by hyperkalemia.

Question 31Pathophysiology and management of kidney disease

A patient with multiple myeloma and a markedly abnormal serum free light chain ratio develops acute kidney injury. Which mechanism best explains the injury?

  1. Acute interstitial nephritis from plasma cell infiltration
  2. Renal vein thrombosis from hypercoagulability
  3. Hypercalcemia-induced vasoconstriction alone
  4. Cast nephropathy from filtered light chains Correct answer.

Explanation

Filtered monoclonal light chains bind Tamm-Horsfall protein in distal tubules, forming obstructive casts and causing direct tubular toxicity. Hypercalcemia and volume depletion may contribute, but cast nephropathy is the characteristic renal lesion of multiple myeloma.

Question 32Pathophysiology and management of kidney disease

Which medication is first-line for scleroderma renal crisis?

  1. High-dose corticosteroids
  2. A loop diuretic alone
  3. An ACE inhibitor Correct answer.
  4. Cyclophosphamide

Explanation

Scleroderma renal crisis is driven by hyperreninemia and angiotensin II-mediated vasoconstriction; ACE inhibitors lower blood pressure and help preserve renal function. Corticosteroids may worsen the crisis, and diuretics alone do not address the renin-angiotensin axis.

Question 33Pathophysiology and management of kidney disease

A patient with membranous nephropathy and heavy proteinuria develops sudden flank pain and gross hematuria. Which complication is most likely?

  1. Renal artery dissection
  2. Ureteral stone
  3. Renal vein thrombosis Correct answer.
  4. Acute pyelonephritis

Explanation

Nephrotic syndrome causes urinary loss of antithrombin III and other anticoagulant proteins, predisposing to renal vein thrombosis, which can present with flank pain and hematuria. Stones and infection can cause similar symptoms but are less directly linked to the nephrotic state.

Question 34Pathophysiology and management of kidney disease

Which medication is most commonly associated with nephrogenic diabetes insipidus?

  1. Hydrochlorothiazide
  2. Furosemide
  3. Spironolactone
  4. Lithium Correct answer.

Explanation

Lithium enters collecting duct cells and impairs vasopressin signaling, reducing aquaporin-2 expression and causing polyuria that is resistant to antidiuretic hormone. Thiazide and loop diuretics alter sodium handling but are not classic causes of nephrogenic diabetes insipidus.

Question 35Pathophysiology and management of kidney disease

Which complement profile is typical of post-streptococcal glomerulonephritis?

  1. Normal C3 and low C4
  2. Low C3 and normal C4 Correct answer.
  3. Low C3 and low C4
  4. Normal C3 and normal C4

Explanation

Post-streptococcal glomerulonephritis activates the alternative complement pathway, lowering C3 while C4 remains normal. Classical pathway activation, as seen in lupus nephritis, typically lowers both C3 and C4.

Question 36Pathophysiology and management of kidney disease

A young adult presents with hemoptysis, hematuria, and red blood cell casts. Which antibody is most likely responsible?

  1. Anti-PLA2R antibody
  2. Anti-dsDNA antibody
  3. Anti-neutrophil cytoplasmic antibody
  4. Anti-GBM antibody Correct answer.

Explanation

Anti-GBM antibodies bind type IV collagen in glomerular and alveolar basement membranes, causing pulmonary hemorrhage and rapidly progressive glomerulonephritis. Anti-dsDNA suggests lupus, ANCA suggests pauci-immune vasculitis, and anti-PLA2R suggests membranous nephropathy.

Question 37Pathophysiology and management of kidney disease

Which primary glomerular disease is the most common cause of glomerulonephritis worldwide?

  1. Membranous nephropathy
  2. Focal segmental glomerulosclerosis
  3. Minimal change disease
  4. IgA nephropathy Correct answer.

Explanation

IgA nephropathy is the most common primary glomerulonephritis worldwide, often presenting with synpharyngitic hematuria. Membranous nephropathy and focal segmental glomerulosclerosis more often cause adult nephrotic syndrome, while minimal change disease is the leading childhood nephrotic cause.

Question 38Pathophysiology and management of kidney disease

Which antibody is most strongly associated with primary membranous nephropathy?

  1. Anti-NELL1 antibody
  2. Anti-glomerular basement membrane antibody
  3. Anti-THSD7A antibody
  4. Anti-phospholipase A2 receptor antibody Correct answer.

Explanation

Anti-phospholipase A2 receptor antibodies are found in about 70% of primary membranous nephropathy and correlate with disease activity. Anti-THSD7A and anti-NELL1 occur in smaller subsets, while anti-GBM antibodies cause Goodpasture disease.

Question 39Pathophysiology and management of kidney disease

A patient with autosomal dominant polycystic kidney disease develops sudden severe headache and neck stiffness. Which complication should be suspected?

  1. Cerebral venous sinus thrombosis
  2. Hypertensive encephalopathy
  3. Acute subdural hematoma
  4. Ruptured berry aneurysm Correct answer.

Explanation

ADPKD is associated with intracranial berry aneurysms, and rupture causes subarachnoid hemorrhage with thunderclap headache and meningismus. Subdural hematoma usually follows trauma, sinus thrombosis tends to cause focal deficits, and encephalopathy causes diffuse symptoms without meningeal signs.

Question 40Pathophysiology and management of kidney disease

A patient with bilateral atherosclerotic renal artery stenosis starts an ACE inhibitor and develops a rise in serum creatinine. Which mechanism explains this change?

  1. Acute tubular necrosis from direct drug toxicity
  2. Loss of angiotensin II-mediated efferent tone Correct answer.
  3. Interstitial nephritis from the medication
  4. Increased afferent arteriolar dilation from bradykinin

Explanation

In renal artery stenosis, glomerular filtration depends on angiotensin II constricting the efferent arteriole; ACE inhibition removes this compensation and lowers GFR. The change is hemodynamic rather than toxic or inflammatory.

Question 41Hemodialysis therapy and vascular access

A patient's arteriovenous fistula is being assessed for readiness for cannulation. Using the 'rule of 6s', the minimum acceptable access blood flow is:

  1. 400 mL/min
  2. 900 mL/min
  3. 200 mL/min
  4. 600 mL/min Correct answer.

Explanation

The rule of 6s describes a mature fistula: flow of at least 600 mL/min, diameter at least 6 mm, depth no more than 6 mm, and at least 6 weeks since creation. Accesses below the flow threshold cannot reliably support treatment blood flows of 300-400 mL/min and are prone to early failure.

Question 42Hemodialysis therapy and vascular access

Which vascular access type carries the lowest risk of bloodstream infection?

  1. Non-tunneled temporary catheter
  2. Arteriovenous fistula Correct answer.
  3. Tunneled cuffed central catheter
  4. Arteriovenous graft

Explanation

Infection risk follows a gradient: native arteriovenous fistula is lowest, followed by graft, then tunneled cuffed catheter, with non-tunneled temporary catheters highest. A fistula contains no foreign material and its high flow resists bacterial seeding.

Question 43Hemodialysis therapy and vascular access

For a tunneled hemodialysis catheter inserted through the right internal jugular vein, the tip should ideally be positioned:

  1. In the proximal right pulmonary artery
  2. In the mid portion of the superior vena cava
  3. At the junction of the brachiocephalic vein and superior vena cava
  4. At the cavoatrial junction or in the upper right atrium Correct answer.

Explanation

Guidelines recommend the catheter tip lie at the cavoatrial junction or in the upper right atrium to achieve the highest reliable blood flows and to reduce vessel wall erosion. Catheters left higher in the vena cava tend to develop fibrin sheaths and inadequate flow.

Question 44Hemodialysis therapy and vascular access

Standard bicarbonate-buffered dialysate has a sodium concentration closest to:

  1. 138 mEq/L Correct answer.
  2. 128 mEq/L
  3. 120 mEq/L
  4. 132 mEq/L

Explanation

Standard dialysate sodium is approximately 137-140 mEq/L, close to the normal serum sodium of 135-145 mEq/L, so that diffusive sodium gain or loss is minimized. Lower concentrations predispose to hypotension and cramping, and higher concentrations increase thirst and interdialytic weight gain.

Question 45Hemodialysis therapy and vascular access

The minimum single-pool Kt/V recommended for a patient receiving three-times-weekly hemodialysis is:

  1. 1.2 Correct answer.
  2. 1.6
  3. 0.8
  4. 2.0

Explanation

The recommended minimum delivered single-pool Kt/V for three-times-weekly hemodialysis is 1.2 per session, which corresponds to a urea reduction ratio of roughly 65%. Consistently lower values are associated with increased mortality and are considered inadequate dialysis.

Question 46Hemodialysis therapy and vascular access

A patient's pre-dialysis blood urea nitrogen is 80 mg/dL and the post-dialysis value is 24 mg/dL. The urea reduction ratio is:

  1. 56%
  2. 30%
  3. 80%
  4. 70% Correct answer.

Explanation

The urea reduction ratio equals (pre-dialysis BUN minus post-dialysis BUN) divided by pre-dialysis BUN, multiplied by 100. Here (80 - 24) / 80 x 100 = 70%, which exceeds the 65% minimum target for adequate dialysis.

Question 47Hemodialysis therapy and vascular access

When a post-dialysis BUN sample is drawn by the slow-flow method, blood flow is reduced to about 100 mL/min and held at that rate for approximately:

  1. 15 seconds Correct answer.
  2. 5 seconds
  3. 60 seconds
  4. 3 seconds

Explanation

After dialysis the arterial urea concentration rises as urea rebounds from tissue, so the sample must not be drawn at full flow. Reducing the pump to 50-100 mL/min for 10-20 seconds clears the line of recirculated blood before the specimen is obtained.

Question 48Hemodialysis therapy and vascular access

A patient becomes diaphoretic and nauseated with a falling blood pressure three hours into treatment. After ultrafiltration is stopped, the most appropriate next step is:

  1. Increase the dialysate temperature to 39 degrees C
  2. Increase the blood flow rate to maximum
  3. Give oral fluids and continue ultrafiltration
  4. Trendelenburg position and a saline bolus Correct answer.

Explanation

Symptomatic intradialytic hypotension is managed by stopping ultrafiltration, placing the patient supine or in Trendelenburg, and giving an isotonic saline bolus. Ultrafiltration is then resumed at a lower rate and the dry weight is reassessed.

Question 49Hemodialysis therapy and vascular access

Near the end of a session with a large fluid removal goal, a patient develops severe leg cramps. The best initial measure is:

  1. Reduce ultrafiltration rate and give saline Correct answer.
  2. Stop the session permanently
  3. Raise the dialysate sodium to 145 mEq/L
  4. Give intravenous potassium chloride 20 mEq

Explanation

Cramps usually reflect rapid or excessive fluid removal with extracellular volume contraction, so the immediate response is to slow or stop ultrafiltration and give a saline bolus. Sodium modeling, cooler dialysate and review of the dry weight help prevent recurrence.

Question 50Hemodialysis therapy and vascular access

A venous line becomes disconnected mid-treatment and the patient develops dyspnea with a falling oxygen saturation. After the pump is stopped and the line clamped, the patient should be positioned:

  1. In Trendelenburg position on the left side Correct answer.
  2. Lying prone with the head turned
  3. Supine with the head raised and legs elevated
  4. Sitting upright and leaning forward

Explanation

Air reaching the right heart can obstruct the pulmonary outflow tract. Trendelenburg position with a left lateral tilt traps air in the right ventricular apex away from the outflow tract while 100% oxygen is given and the circuit is secured.