45. B. For normovolemic, asymptomatic hyponatremic patients, free water restriction is
generally the treatment of choice. There is no role for hypertonic saline in these
patients. The volume of restriction should be based on the patient’s renal diluting
capacity. If patient is unable to adhere to fluid restrictions, consider use of a loop
diuretic (e.g., furosemide) to increase free water excretion in the kidneys.
Demeclocycline is a tetracycline antibiotic that has a secondary effect of reducing
the responsiveness of the collecting tubule cells to antidiuretic hormone, thus
46. C. As with many diuretics, furosemide can cause dehydration and electrolyte
imbalance, including loss of potassium, calcium, sodium, and magnesium. Excessive
use of furosemide will most likely lead to a metabolic alkalosis due to
hypochloremia and hypokalemia.
47. A. With epidural anesthesia, consider avoiding the use of loss of resistance to air
for identifying the epidural space, as air will provide an interface and cause
dissipation of shock wave energy resulting in local tissue injury. Animal experiments
have shown epidural tissue damage following injection of air followed by exposure
48. D. Water immersion produces significant changes in the cardiovascular and
respiratory systems. Cardiovascular changes include an increase in central blood
volume, with an increase in central venous and pulmonary artery pressures, which are
directly correlated with the depth of immersion. The sitting position, together with
either general or epidural anesthesia, would tend to cause peripheral pooling and
decreased venous return. Respiratory changes with immersion up to the clavicles are
significant: functional residual capacity and vital capacity are reduced by 20% to
30%; pulmonary blood flow has been shown to increase; and tight abdominal straps
and the hydrostatic pressure of water on the thorax impart a characteristic of shallow,
49. C. Shock wave–induced cardiac arrhythmias occur in up to 10% to 14% of patients
undergoing lithotripsy despite the fact that shock waves are purposefully
synchronized with the patient’s ECG and are delivered in the refractory period of the
50. C. An advantage of providing a general anesthetic for ESWL is that ventilatory
parameters can be controlled using high frequency and low volumes to decrease
stone movement with respiration.
51. A. Contraindications for lithotripsy include the following: pregnancy, a large aortic
aneurysm, certain bleeding conditions, and certain skeletal deformities that prevent
accurate focus of shock waves. Patients with abdominally placed cardiac
pacemakers should notify their doctor. Rate-responsive pacemakers that are
implanted in the abdomen may be damaged during lithotripsy. Orthopedic prostheses,
including hip prostheses and even Harrington rods, are generally not a problem as
long as they can be kept out of the blast path.
52. A. Creatinine clearance test evaluates how efficiently the kidneys clear creatinine
from the blood. Creatinine, a waste product of muscle energy metabolism, is
produced at a constant rate that is proportional to the muscle mass of the individual.
Because the body does not recycle it, all of the creatinine filtered by the kidneys in a
given amount of time is excreted in the urine, making creatinine clearance a very
specific measurement of kidney function.
53. B. Succinylcholine, atracurium, and cis-atracurium have theoretical advantages
because their elimination occurs via plasma cholinesterases and Hofmann
degradation, respectively, mostly independent of renal or hepatic function. Fentanyl
and methadone are also considered relatively safe in renal failure as they have no
active metabolites. Methadone has limited plasma accumulation in renal failure as it
is primarily eliminated in the feces. In terms of reversal agents, renal excretion
accounts for approximately 50% of the clearance of neostigmine and approximately
75% of elimination of edrophonium and pyridostigmine. Renal failure allows some
protection against residual neuromuscular blockade because renal elimination half
times of anticholinesterase drugs is prolonged.
54. A. Acute tubular necrosis is classified as a “renal” (e.g., not prerenal or postrenal)
cause of acute kidney injury. Diagnosis is made by a fractional excretion of sodium
>3%, greater than expected urine sodium concentration with low osmolality and
presence of muddy casts on urinalysis. A sensitive indicator of tubular function is
sodium handling because the ability of an injured tubule to reabsorb sodium is
impaired, whereas an intact tubule can maintain this resorptive capacity. If the patient
has tubular damage for any reason, the urinary sodium will be greater than expected.
Keep in mind that the use of diuretics, however, can complicate the interpretation of
these results. Low urine flow, concentrated urine, or an acidic environment can
contribute to the formation of hyaline casts, pointing to hypovolemia and prerenal
Table 14-3 Differentiation between Prerenal and Intrinsic Renal Failure.
PARAMETER PRERENAL FAILURE ACUTETUBULAR NECROSIS
Urine osmolality (mOsm/kg) >500 <350
Urine specific gravity >1,020 <1,010
Urine:plasma urea ratio >10:1 <7:1
55. B. Urinalysis reveals a prerenal state. Treatment focuses on correcting the cause of
the prerenal acute renal failure, most often with a fluid challenge. Depending on the
cause, the condition often reverses itself within a couple of days after normal blood
flow to the kidneys has been restored. But if it is not reversed or treated successfully
and quickly, prerenal acute renal failure can cause tissue death in the kidneys and
lead to intrinsic (intrarenal) acute renal failure.
56. A. Hyperchloremic acidosis is a well-recognized entity as a consequence of large
volume administration of some intravenous fluids. Normal saline (0.9% sodium
chloride solution) and colloids suspended in normal saline are often infused because
they are easily available, and are isotonic with plasma. When a patient is given
normal saline (a hyperchloremic solution), chloride levels can significantly increase.
It is the chloride anion that is the ultimate cause of the acidosis. Consider this
equation: sodium chloride combines with water: NaCl + H2O → HCl + NaOH. The
strong acid (HCl) and the strong base (NaOH) should cancel each other out, with no
effect on pH. However, because the normal concentrations of Na
serum are 140 and 100, respectively, adding normal saline (154 mEq Na and 154
mEq Cl) causes the chloride to increase proportionately more than the sodium. This
increase in chloride tips the acid–base balance toward HCl, thereby causing a
57. D. Chronic pain is common in chronic kidney disease and most will rate their pain
as moderate to severe. The absorption, metabolism, and renal clearance of opioids
are complex in renal failure. However, with the appropriate selection and titration of
opioids, patients with renal failure can achieve analgesia with minimal risk of
adverse effects. Meperidine is not recommended in renal failure due to accumulation
of normeperidine, which may cause seizures. Morphine is not recommended for
chronic use in renal insufficiency due to the rapid accumulation of its active
nondialyzable metabolite (morphine-6-glucuronide). Codeine has been reported to
cause profound renal toxicity, which can be delayed and may occur after trivial
doses. Dextropropoxyphene is associated with central nervous system and cardiac
toxicity and is not recommended for use in patients with renal failure. On the other
hand, fentanyl is considered relatively safe in renal failure, as it has no active
A. Is characterized by a relative lack of insulin plus resistance to endogenous
C. Affects 95% of patients with diabetes
D. Can be controlled with diet, weight loss, and oral hypoglycemic agents
2. Preoperative assessment of patients with diabetes mellitus should include
A. An assessment of functional status
B. 24-Hour creatinine clearance
D. Cancellation of the surgical case if HbA1c >10%
3. Preferred anesthetic agent in a patient with hyperthyroidism includes
4. Multiple endocrine neoplasia (MEN) I syndrome includes
A. Pheochromocytoma, medullary thyroid carcinoma, parathyroid hyperplasia
B. Pancreas tumors, medullary thyroid carcinoma, pituitary adenoma
C. Pheochromocytoma, medullary thyroid carcinoma, mucosal neuromas
D. Pancreas tumors, pituitary adenoma, parathyroid hyperplasia
5. Laboratory findings in primary hypothyroidism are
A. Low TSH, elevated T3, elevated T4
D. Elevated TSH, low T3, low T4
6. Obese patients may experience rapid oxygen desaturation during induction of
A. A decrease in lung compliance
B. A reduction in functional residual capacity (FRC)
C. A history of obstructive sleep apnea
7. A 39-year-old woman with a history of headaches, hypertension, palpitations, and
nephrolithiasis is undergoing a parathyroidectomy for parathyroid adenoma. During
induction, she develops severe hypertension and tachycardia. The most likely
-receptor antagonist and a nonselective β-adrenergic receptor
C. Irreversible, nonselective α-adrenergic receptor antagonist
9. A 40-year-old woman with a history of Graves disease is in the recovery room after
undergoing a CT scan under general anesthesia. While in the recovery room, her
blood pressure drops to 80/55 mm Hg, her heart rate increases to 140 bpm, and she
becomes agitated and complains of difficulty breathing and feeling hot. The most
likely diagnosis for these signs is
10. Treatment of thyroid storm includes
11. During a postoperative check on a 53-year-old patient who underwent a total
thyroidectomy earlier in the day, you notice that he is stridorous and is complaining
of muscle cramps. The best treatment for these symptoms is
A. Administration of calcium gluconate
C. Reintubation for airway protection
D. Administration of sodium bicarbonate
12. Patients with obstructive sleep apnea (OSA)
A. Are at increased risk of left-heart failure
B. Have the same perioperative complication rate as patients without OSA
C. May have an increased likelihood of difficult intubation
D. Rarely require continuous positive airway pressure (CPAP) after bariatric
13. A 39-year-old patient with a BMI of 45 kg/m2
is scheduled for a Roux-en-Y gastric
bypass. She has a history of hypertension. Your perioperative concerns include
A. Preparation for a rapid sequence induction, since she is at increased risk for
aspiration of gastric contents
B. Placing her in the reverse Trendelenburg position to reduce atelectasis in
dependent areas of the lung and move the chest and breast tissue caudally to
allow easier access to the mouth for endotracheal intubation
C. Need to dose water-soluble drugs (e.g., neuromuscular-blocking agents) to
D. More frequent administration of lipid-soluble drugs will be needed
14. During the preoperative evaluation of a critically ill patient with ischemic bowel
scheduled for a second look laparotomy and possible abdominal closure, you notice
multiple electrolyte abnormalities including hypophosphatemia, hypokalemia, and
hypomagnesemia. A possible cause for these electrolyte abnormalities is
15. Complications of cricoid pressure include
B. Displacement of thoracic spine
C. Worsening of view of airway in patients with difficult airway
D. Need for less pressure in parturients
16. You are evaluating a 55-year-old patient with type 2 diabetes mellitus for a total
knee replacement. His diabetes is controlled on a regimen of Glucophage
(metformin), NPH insulin twice a day, and insulin sliding scale. Perioperative
instructions for glucose management should include
A. Give half of the NPH dose if morning blood glucose level is at least 150 mg/dL
B. Give regular insulin dose according to morning blood glucose level
C. Holding metformin for 48 hours preoperatively to avoid risk of fatal lactic
D. Starting insulin infusion with target glucose range of 81 to 108 mg/dL
A. Grow rapidly, and patients are often symptomatic with carcinoid syndrome
B. Synthesize epinephrine and norepinephrine
C. Can cause left-sided heart failure due to mitral and aortic valve damage
D. Can cause right-sided heart failure due to tricuspid and pulmonary valve
18. You are taking care of a 67-year-old patient undergoing a parathyroidectomy. The
patient is hypercalcemic with a serum calcium of 20 mg/dL. Anesthetic
considerations should include all of the following, except
A. Hypoventilation to decrease ionized calcium level
B. Careful titration of neuromuscular-blocking agents
C. Hydration with normal saline and diuresis with furosemide
D. Care with laryngoscopy because of risk of vertebral compression
19. Clinical manifestations of mineralocorticoid excess include
20. Normal daily cortisol production (mg/day) in adults is
21. A 75-year-old patient with coronary artery disease, hypertension, and chronic
obstructive pulmonary disease (COPD) is undergoing a left colectomy for cancer.
He had a COPD exacerbation 4 months ago and was on steroids for a week at the
A. Should be given at a dose greater than 10 times the normal daily cortisol
B. Should not exceed 100 to 150 mg of cortisol equivalent per day
C. Is not necessary in this patient
D. Should include 100 mg of cortisol, tapered over 5 to 7 days
22. Physiologic effects of chronically elevated corticosteroid levels (Cushing syndrome)
include all of the following, except
23. You are taking care of a 45-year-old patient undergoing a left adrenalectomy for a
pheochromocytoma. Intraoperative management includes
A. Use of ketamine as an induction agent to counteract the effects preoperative of
B. Long-acting antihypertensive agents should be available to treat hypertension
C. Judicious fluid replacement as these patients are usually volume-overloaded
D. Magnesium sulfate infusion to treat hypertension
24. A 75-year-old, 110-kg patient is scheduled for a radical prostatectomy. He has a
history of hypertension and type 2 diabetes mellitus. His preoperative ECG is
significant for Q waves in leads II, III, and aVF, though the patient denies having a
previous myocardial infarction. His medications include insulin, Glucophage
(metformin), a β-blocker, and an angiotensin-receptor blocker. Upon induction, his
blood pressure drops from 150/80 to 65/40. The most likely cause of hypotension is
A. Use of angiotensin-receptor blocker
B. Diabetic autonomic neuropathy
25. Patients with type 1 diabetes mellitus may be difficult to intubate because of
A. Increased supraglottic soft tissue due to chronic hyperglycemia
B. An association between type 1 diabetes and an anterior larynx
D. An increased incidence of obesity in patients with type 1 diabetes
prevent hyperglycemic ketoacidosis and other complications. Most patients carrying
the diagnoses of diabetes (95%) have type 2 diabetes, which is characterized by a
relative lack of insulin plus resistance to endogenous insulin. Type 2 diabetes can be
controlled with diet and weight loss, and oral agents, though these patients may also
2. A. Complications of diabetes result largely from microangiopathy and
macroangiopathy. Diabetes is a well-recognized risk factor for coronary artery
disease (CAD). Cardiac autonomic neuropathy may mask angina pectoris and
obscure the presence of CAD. Hence, a careful assessment of functional status and
any symptoms such as increasing dyspnea on exertion and fatigue may be indicative
of significant CAD. While diabetes is a leading cause of renal failure, there is no
evidence that a preoperative evaluation with a 24-hour creatinine clearance is
helpful. While the risk of complications of diabetes increases with increasing HbA1c
levels, and there is evidence that higher HbA1c
levels are associated with adverse
outcomes following a variety of surgical procedures, there is insufficient evidence to
recommend an upper limit of HbA1c prior to elective surgery. The risks associated
with poor glycemic control should be balanced against the necessity for surgery.
3. C. In patients with hyperthyroidism, the goal of anesthesia is to avoid an increase
in heart rate or sympathetic activation. Ketamine, desflurane, and meperidine cause
sympathetic stimulation and tachycardia. Conversely, anesthetics and techniques that
reduce or blunt sympathetic activity are preferred. Sevoflurane for anesthesia, and
fentanyl and its congeners for analgesia would be favored. Regional anesthesia, when
practical, might also be efficacious in avoiding sympathetic activation.
4. D. MEN I syndrome includes the triad of tumors of the pancreas, pituitary, and
parathyroid glands and is inherited as an autosomal-dominant trait. Medullary thyroid
carcinomas are a component of the MEN II endocrine syndromes, of which there are
6. B. Obesity is associated with obstructive sleep apnea, decreased pulmonary
compliance, and lung volumes suggestive of restrictive lung disease. Total
pulmonary compliance decreases due to a decrease in both chest-wall compliance
and lung compliance. Chest-wall compliance decreases because of excessive adipose
tissue over the thorax, while lung compliance decreases because of the increased
abdominal mass, which pushes the diaphragm cephalad causing an increase in
pulmonary blood volume. The FRC of the lung is the volume of air present in the
lungs at the end of passive expiration and reflects a balance between the elastic
recoil of the lungs and the pleural pressure. With obesity, there is a shift in this
balance due to adipose tissue in the chest wall and abdomen, resulting in a decreased
FRC. The FRC is the reservoir of oxygen during the apneic state associated with the
induction of general anesthesia. Thus, the reduction of FRC associated with obesity
results in greater oxygen desaturation during the induction of general anesthesia.
7. D. While inadequate anesthesia and thyroid storm may result in intraoperative
hypertension and tachycardia, the most likely diagnosis is pheochromocytoma.
Pheochromocytoma is a catecholamine-secreting tumor and is part of the multiple
endocrine neoplasia (MEN) type II syndrome, which consists of pheochromocytoma,
medullary thyroid carcinoma, and parathyroid adenoma. Symptoms associated with
pheochromocytoma include paroxysmal headache, hypertension, diaphoresis, and
8. C. Phenoxybenzamine is an irreversible, nonselective α-adrenergic receptor
antagonist used preoperatively for adrenergic blockade in patients with
pheochromocytomas. It blocks both the postsynaptic α1 and presynaptic α2
in the nervous system, thereby reducing sympathetic activity. Clinical signs of the
optimal dose of phenoxybenzamine are a stuffy nose and slight dizziness due to
postural hypotension. Doxazosin is a reversible, selective α1
is an alternative to phenoxybenzamine for treatment of pheochromocytoma. In
patients with pheochromocytoma, α-blockade is always started prior to β-blockade.
Starting β-blockade first will lead to unopposed α stimulation causing further
increase in the blood pressure.
9. A. Thyroid storm is characterized by fever, tachycardia, altered mental status,
and hypertension, presenting most often in the postanesthesia care unit or in the
immediate postoperative period (24 hours). Hypertension may be followed by
congestive heart failure that is associated with hypotension and shock. Thyroid storm
is a state of severe hypermetabolism induced by excessive release of thyroid
hormones. It can be precipitated by surgery, stress, infection, and drugs including
chemotherapeutic agents, anticholinergic, and adrenergic drugs such as
pseudoephedrine, amiodarone, and iodinated contrast media. Unlike malignant
hyperthermia, it is not associated with muscle rigidity, an elevated creatinine kinase,
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