Mksap Pulmonary

(1)

MKSAP 15

MKSAP 15 Pulmonary a

Pulmonary and Critical

nd Critical

MKSAP 15 Pu

lmonary an

d Critical

Care Medicine

Questions

Answers &

Answers & Critiques

Critiques

Answers

& Critiques

CD1

(2)

Question 1

A 28-y

ear-old man is evaluated for a 6-month history of ep

isodic dyspnea, cough, a

nd wheezing.

As a child, he had asthma and allergies, but he has bee

n asymptomatic since his early

teenage

years. His recent symptoms started after an

upper respiratory tract infection, and they are often

triggered by eercise or eposure to cold a

ir. He is also awa!ened with asthma symptoms " or

6

6 nights a month. He is otherwise healthy and ta!es no medications.

nights a month. He is otherwise healthy and ta!es no medications.

#n physical eamination, vital signs are normal. $here is scattered wheezing in both lung fields.

%hest radiograph is normal. &pirometry shows an '()

**

of + of predicted with a *"

improvement after inhaled albuterol.

hich of the following is the most

appropriate therapy for this patient/

00A-Azithromycin

A-Azithromycin

00B-Inhaled albuterol as needed

B-Inhaled albuterol as needed

00C-Inhaled low-dose corticosteroids plus inhaled albuterol as needed

C-Inhaled low-dose corticosteroids plus inhaled albuterol as needed

00D-Long-acting β-agonist

D-Long-acting β-agonist

(3)

Question 1

A 28-y

ear-old man is evaluated for a 6-month history of ep

isodic dyspnea, cough, a

nd wheezing.

As a child, he had asthma and allergies, but he has bee

n asymptomatic since his early

teenage

years. His recent symptoms started after an

upper respiratory tract infection, and they are often

triggered by eercise or eposure to cold a

ir. He is also awa!ened with asthma symptoms " or

6

6 nights a month. He is otherwise healthy and ta!es no medications.

nights a month. He is otherwise healthy and ta!es no medications.

#n physical eamination, vital signs are normal. $here is scattered wheezing in both lung fields.

%hest radiograph is normal. &pirometry shows an '()

**

of + of predicted with a *"

improvement after inhaled albuterol.

hich of the following is the most

appropriate therapy for this patient/

00A-Azithromycin

A-Azithromycin

00B-Inhaled albuterol as needed

B-Inhaled albuterol as needed

00C-Inhaled low-dose corticosteroids plus inhaled albuterol as needed

C-Inhaled low-dose corticosteroids plus inhaled albuterol as needed

00D-Long-acting β-agonist

D-Long-acting β-agonist

(4)

Answer and C

Answer and Critique 1

ritique 1

Answer and C

ritique 1

(Correct Answer:

C)

(ducational #b1ective $reat persistent asthma.

Key oint

Key oint

003nhaled corticosteroids are the cornerstone of therapy for persistent asthma.3nhaled corticosteroids are the cornerstone of therapy for persistent asthma.

00 Asthma symptom

Asthma symptoms on 2 or more days a wee! 4or 2 or more nights a ms on 2 or more days a wee! 4or 2 or more nights a month5 is the defining characterisonth5 is the defining characteristic of persistent asthmtic of persistent asthma.a.

3nhaled corticosteroids are the cornerstone of therapy for persistent asthma. egular use of inhaled corticosteroids is associated

with improved pulmonary function, reduced airway hyperresponsiveness, decreased asthma eacerbations, and reduced

mortality. &ide effects of inhaled corticosteroids include oral candidiasis and dysphonia related to laryngeal muscle myopathy.

&ystemic effects may occur with use of inhaled corticosteroids and are generally related to the dose and duration of use. 3n adults,

these effects include osteopenia, s!in thinning, and increased ris! for cataracts or glaucoma. $herefore, the lowest dose

consistent with disease control should be used. $he treatment should be reevaluated every 7 to 6 months in stable patients, and

ad1ustments made to step-up or step-down therapy based on disease control and occurrence of eacerbations. 3n between visits,

patients should use a written asthma management plan, devised by their physician, to guide potential changes to their treatment.

00 Albuterol should be used as needed in all

Albuterol should be used as needed in all patients with asthma, but by itself is not adepatients with asthma, but by itself is not adeuate therapy because it does not affectuate therapy because it does not affect

the underlying airway inflammation. 9ong-acting :-agonists 4salmeterol and formoterol5 provide bronchodilation for up to *2 hours

and are effective in preventing eercise-induced asthma. $hese drugs do not have a clinically significant anti-inflammatory effect;

therefore, their use without concomitant administration of corticosteroids may mas! worsening of asthma control and lead to

increased asthma-related complications, including the possibility of increased asthma-related deaths. $herefore, long-acting

:-agonists are not appropriate as monotherapy or in place of inhaled corticosteroids. $he use of antibiotics for atypical infections

agonists are not appropriate as monotherapy or in place of inhaled corticosteroids. $he use of antibiotics for atypical infections

4<ycoplasma, %hlamydia5 in asthma is under investigation. However, antibiotic therapy is not recommended unless there is

evidence of an acute bacterial infection.

(5)

Question 2

0 A +7-year-old woman is evaluated in the em ergency department for a 2-wee! history of worsening

dyspnea and a dry cough. &he has not had fever or any recent travel. 3diopathic pulmonary fibrosis was

diagnosed 2 years ago by open l ung biopsy. &he also has a history of hypertension and

gastroesophageal reflu disease. Her medications are prednisone, diltiazem, hydrochlorothiazide, and

omeprazole.

0 #n physical eamination, she is afebrile; the blood pressure is *=2>86 mm Hg, the pulse rate is ?+>min,

the respiration rate is 28>min, and the @<3 is 2+. #ygen saturation with the patient breathing oygen, *

9>min by face mas!, is ?. $here are dry crac!les at the lung bases etending half way up the chest

bilaterally. %ardiac and abdominal eaminations are normal. ram stain of sputum is negative; culture is

pending. %$ scan of the chest is negative for pulmonary embolism but shows new areas of alveolar

infiltrates and consolidation superimposed on previous basilar, reticular, and honeycomb changes.

hich of the following is the most appropriate net test in the evaluation of this patient/

0 A-Bronchoscopy with bronchoal!eolar la!age

0 B-"ungal serologies

0 C-#ight-heart catheterization

0 D-$wallowing e!aluation

(6)

Answer and Critique 2

(Correct Answer:

A)

Educational Objective: Evaluate an acute exacerbation of idiopathic pulmonary fibrosis. Key Point:

0@ronchoalveolar lavage is the diagnostic procedure to eclude opportunistic infection in an apparent acute eacerbation of idiopathic pulmonary fibrosis.

0$he two immediate diagnostic considerations in this patient are respiratory infection and an acute eacerbation of pulmonary fibrosis. @oth diagnostic possibilities may be evaluated by bronchoalveolar lavage with studies to detect bacterial organisms, opportunistic pathogens 4for eample, Pneumocystis jirovecii 5, and viral pathogens. outine sputum evaluation for ram stain and culture is not sensitive enough to detect opportunistic infectious organisms. Biagnostic criteria for an acute eacerbation of pulmonary fibrosis include eclusion of opportunistic respiratory infections via

endotracheal aspiration or bronchoalveolar lavage as well as eclusion of pulmonary embolism, left ventricular failure, and other causes of acute lung in1ury. $he incidence of an acute eacerbation of idiopathic pulmonary fibrosis is not certain but li!ely ranges between " and =. 3n patients with pulmonary fibrosis admitted to the intensive care unit for respiratory failure, the incidence may be as high as 6 with a reported mortality rate between 8 and *. Co therapy has been shown to be beneficial.

0'ungal serologies may be helpful to diagnose opportunistic infection in this patient. However, bronchoalveolar lavage is more sensitive, and results more readily available for detecting other opportunistic pathogens that need to be ecluded in this immunosuppressed patient. ight-heart catheterization is not part of the initial evaluation of patients with a suspected acute eacerbation of idiopathic pulmonary fibrosis. Aspiration may cause acute lung in1ury and may trigger an acute eacerbation of idiopathic pulmonary fibrosis, but swallowing evaluation is unli!ely to be diagnostic in this patient with no history of aspiration.

(7)

Question 3

0 A 6"-year-old woman is evaluated in a follow-up eamination for dyspnea, chronic cough, and

mucoid sputum; she was diagnosed with chronic obstructive pulmonary disease 7 years ago.

$he patient has a =-pac!-year history of cigarette smo!ing, but uit smo!ing * year ago. &he is

otherwise healthy, and her only medication is inhaled albuterol as needed.

0 #n physical eamination, vital signs are normal. @reath sounds are decreased, but there is no

edema or 1ugular venous distention. &pirometry shows an '()

*

of 62 of predicted and an

'()

*

>')% ratio of 6". %hest radiograph shows mild hyperinflation.

hich of the following is the most appropriate therapy for this patient/

A-Add a long-acting β

%

-agonist

B-Add an inhaled corticosteroid

C-Add an oral corticosteroid

D-Add theophylline and montelu&ast

E-Continue current albuterol therapy

(8)

Answer and Critique 3

(Correct Answer:

A)

Educational Objective: Manage moderate chronic obstructive pulmonary disease. Key Point:

0 3n patients with moderate chronic obstructive pulmonary disease, therapy with a long-acting :2-agonist or a long-acting anticholinergic agent improves

uality of life and pulmonary function compared with therapy with short-acting bronchodilators alone.

0$his patient has stage 33 chronic obstructive pulmonary disease 4%#DB5 as defined by the guidelines of the lobal 3nitiative for #bstructive 9ung Bisease 4#9B5. #9B stage 33 disease is defined by a postbronchodilator '()*>')% ratio less than + and an '()* less than 8 but more than " of

predicted with or without chronic symptoms. 3n patients with #9B stage 33 disease, maintenance treatment with one or more long-acting bronchodilators such as a long-acting :2-agonist 4salmeterol or formoterol5 is r ecommended, along with as-needed albuterol. Dulmonary rehabilitation can be considered

in addition to medical treatment in symptomatic patients. &tarting or adding a long-acting anticholinergic agent would also be appropriate.

03nhaled corticosteroids, oral corticosteroids, theophylline, and montelu!ast would be inappropriate f or this patient. $heophyllineEs narrow therapeutic window and poor bronchodilator effect ma!e it a poor choice. #ral corticosteroids are not recommended routinely in %#DB because of their systemic side effects. <ontelu!ast is used as a third-line agent in asthma but has not been shown to be efficacious in %#DB. $he #9B guidelines recommend consideration of inhaled corticosteroids in patients whose lung function is less than " and who eperience recurrent eacerbations. hen inhaled corticosteroids are combined with a long-acting :2-agonist in such patients, the rate of decline in uality of life and health status is significantly reduced

and the freuency of acute eacerbations is reduced by 2"; lung function is also improved and dyspnea alleviated.

0%ontinuing current therapy with albuterol would not be appropriate because using a short-acting bronchodilator alone does not afford effective therapy for #9B stage 33 disease and reuires more freuent treatments.

0$wo recent long-term studies of more than **, patients have evaluated treatment for patients with #9B stages 33 to 3). $he $#%H study and the FD93'$ study showed that in patients with %#DB, therapy with a long-acting :2-agonist or a long-acting anticholinergic agent in addition to a short-acting

(9)

Question 4

0 A "2-year-old woman is evaluated after a screening %$ colonography detected a 7-mm nodule in the

right lower lobe of the lung. A tortuous colon prevented complete screening colonoscopy. %$ scan of

the chest showed no additional nodules and was otherwise normal. $he patient has never smo!ed; she

wor!s in the home and has not been eposed to potential carcinogens. &he has not had a chest

radiograph or other imaging procedure, ecept mammography. Her medical history includes only

hyperlipidemia, and her only medication is simvastatin. Her family history is unremar!able.

0 #n physical eamination, vital signs are normal. (amination of the s!in is normal; there is no

lymphadenopathy, and the lungs are clear.

hich of the following is the most appropriate net step in the management of this patient/

A-Chest radiograph in ' months

B-C( scan o) the chest in ' months

C-C( scan o) the chest in * months

D-C( scan o) the chest in +% months

E-,o )ollow-up

(10)

Answer and Critique 4

(Correct Answer:

E)

Educational Objective: Evaluate a low-risk patient with a very small pulmonary nodule.

Key Point:

03n a patient at low ris! for malignancy no follow-up is reuired for an incidentally noted pulmonary

nodule = mm or smaller.

0&tudies of chest %$ screening have shown that 2" to " of patients have one or more

pulmonary nodules detected on the initial %$ scan. (ven in patients at relatively high ris! for lung

cancer, the li!elihood that a small nodule is malignant is low 4G*5. 'or eample, the ris! of

malignancy is about .2 for nodules smaller than 7 mm and .? for nodules = to + mm. $he

'leischner &ociety recommendations include no follow-up for low-ris! patients with nodules = mm

or smaller and follow-up %$ at *2 months for patients with such nodules who are at ris! for lung

cancer. <ore freuent follow-up is not recommended for nodules of this size. $his small nodule is

not li!ely to be visible on chest radiograph, and, therefore, such imaging would not be helpful.

(11)

Question 5

0 A 7-year-old man is eva luated for difficulty weaning from the ventilator. $he patient was intu bated + days

ago for a severe eacerbation of asthma. Bespite receiving a high-dose inhaled :-agonist;

methylprednisolone, 6 mg>d; and aggressive sedation, he had persistent severe auto-positive

end-epiratory pressure with elevated ventilator pressures. $herefore, a continuous infusion of vecuronium, a

paralytic agent, was started and continued for 2= hours until his respiratory mechanics improved. $oday, he

underwent a ventilator weaning trial but became tachycardic and diaphoretic with a rapid shallow breathing

inde of *2.

0 #n physical eamination, the patient is alert and responsive; vital signs are normal. $here is minimal

epiratory wheezing and otherwise normal vesicular breath sounds. He has flaccid wea!ness involving all

etremities, including decreased bilateral hand grip strength. $here is no rash. outine laboratory studies

reveal normal liver enzyme tests and renal function.

hich of the following is the most li!ely cause for the patientEs difficulty weaning from the ventilator/

A-Acute in)lammatory demyelinating polyneuropathy .uillain-Barr/ syndrome0

B-Churg-$trauss syndrome

C-Intensi!e care unit1ac2uired wea&ness

D-rolonged neuromuscular bloc&ade

(12)

Answer and Critique 5

(Correct Answer:

C)

Educational Objective: Diagnose intensive care unitac!uired weakness. Key Point;

0Datients with intensive care unitacuired wea!ness have diffuse, flaccid wea!ness and often present with difficulty with ventilator weaning.

0Datients with intensive care unit 43%F5acuired wea!ness have diffuse wea!ness and decreased muscle tone. $he disorder may be first recognized in patients with uneplained difficulty weaning from the ventilator. "#$-ac!uired weakness is a term used to encompass critical-illness poly-neuropathy and critical-illness myopathy. $reatment with paralytic agents and systemic corticosteroids, as well as sepsis and immobilization, increase the ris! of developing 3%F-acuired wea!ness. $reatment is supportive, including discontinuation or reduction of corticosteroids, aggressive management of eisting disorders, and physical rehabilitation.

0 Acute inflammatory demyelinating polyneuropathy 4uillain-@arrI syndrome5 can also cause diffuse wea!ness, but in contrast to this patient, wea!ness is the presenting symptom. 'urthermore, wea!ness associated with acute inflammatory demyelinating polyneuropathy typically develops gradually over a longer time course 4* to 2 wee!s5 and typically is preceded by an inf ection. 0Drolonged neuromuscular bloc!ade is a condition in which the effect of paralytic agents, such as vecuronium, can persist f or days after discontinuing the medication. However, this is rarely encountered and is caused by altered drug metabolism due to liver and>or renal dysfunction, neither of which this patient has.

0%hurg-&trauss syndrome is associated with asthm a and, in the vasculitic stage, can cause wea!ness. However, the syndrome most often manifests as mononeuritis multiple rather than generalized wea!ness. 'urthermore, this patient does not have other manifestations of vasculitis such as rash or renal dysfunction.

(13)

Question 6

0 A "=-year-old man is evaluated in the emergency department f or a *-hour history of c hest pain with mild dyspnea.

$he patient had been hospitalized * wee! ago for a colectomy for colon cancer. His medical history also includes

hypertension and nephrotic syndrome secondary to membranous glomerulonephritis, and his medications are

furosemide, ramipril, and pravastatin.

0 #n physical eamination the temperature is 7+." J% 4 J'5, the pulse rate is 2>min, the respiration rate is

2=>min, the blood pressure is **>6 mm Hg, and the @<3 is 7. #ygen saturation is 8? with the patient

breathing ambient air and ?+ on oygen, = 9>min. %ardiac eamination shows tachycardia and an &

=

. @reath

sounds are normal. %hest radiograph is negative for infiltrates, widened mediastinum, and pneumothora. &erum

creatinine concentration is 2.* mg>d9 4*8".6 Kmol>95. (mpiric unfractionated heparin therapy is begun.

hich of the following is the best test to confirm the diagnosis in this patient/

A-Assay )or plasma D-dimer

B-C( angiography

C-Lower e3tremity ultrasonography

D-4easurement o) antithrombin III

E-5entilation6per)usion scan

(14)

Answer and Critique 6

(Correct Answer:

E)

Educational Objective: #onfirm the clinical diagnosis of acute pulmonary embolism.

Key Point:

0(ither ventilation>perfusion scanning or contrast-enhanced %$ scanning 4if not contraindicated5 performed with a

specific protocol to detect pulmonary embolism is an appropriate noninvasive test to diagnose acute pulmonary

embolism.

0$his patient is at high ris! for pulmonary embolism because of his recent hospitalization, cancer, and nephrotic

syndrome. A positive ventilation>perfusion scan would confirm the diagnosis of pulmonary embolism in this patient with

a high pretest probability for the condition, especially in the absence of parenchymal lung defects on chest radiograph.

0$he probability of pulmonary embolism was very high based on this presentation that included chest pain, dyspnea,

recent hospitalization and surgery, active cancer, and a protein-losing nephropathy. A negative B-dimer test would not

be sufficient evidence to rule out a pulmonary embolism under these circumstances, and a high B -dimer level would

add little to the diagnostic wor!-up. Becreased antithrombin 333 levels may result from nephrotic syndrome, and levels

are lowered during acute thrombosis, especially during treatment with heparin. $herefore, measuring antithrombin 333

would add little to the accuracy of the diagnosis of pulmonary embolism or have any implication for immediate

management decisions. 9ower etremity ultrasonography can disclose asymptomatic deep venous thrombosis in a

small percentage of patients presenting with symptoms of pulmonary embolism. However, the yield is relatively low

and ventilation>perfusion scanning would have a much higher degree of accuracy. %$ angiography is an acceptable

modality to diagnose acute pulmonary embolism but reuires a significant amount of contrast infusion 4as much as a

pulmonary angiogram5 which would be contraindicated in a patient with an elevated serum creatinine level.

(15)

Question 7

A An *8-year-old man is evaluated in the emergency department after his mother found him unconscious in his bed at home. &he reported that her son had gone to a party two nights ago, but she was not sure when he returned home. hen she chec!ed on him, he was unarousable. He has no significant medical history and ta!es no medications.

3n the emergency department, he is afebrile, bl ood pressure is **>+ mm Hg, the pulse rate is ">min, and respiration rate is 6>min; he is intubated for airway protection. Laboratory studies78emoglobin +%9% g6dL +%% g6L0 0Leu&ocyte count ':;;6<L '9: = +;>_6L0 0latelet count ++;?;;;6<L ++; = +;>_6L0 0Creatinin e '9% mg6dL %@%9> <mol6L0 0Aspartate aminotrans)erase @; 6L 0Alanine aminotrans)erase :* 6L 0Creatine &inase +@?:;; 6L 0I,# +9%

0 Al!aline phosphatase, bilirubin, and albumin are normal. Frine dipstic! is =L positive for occult blood. @lood alcohol level is .8 g>d9 4*+= mmol>95. $oicology testing is positive for opiates and cocaine. @ladder catheterization reveals only 7 m9 of brown urine.

hich of the f ollowing is the most li!ely cause of the patientEs renal failure/ 0A-8emolytic anemia

0B-8emolytic-uremic syndrome 0C-8epatorenal syndrome 0D-#habdomyolysis 0E-$epsis

(16)

Answer and Critique 7

(Correct Answer:

D)

Educational Objective: Diagnose rhabdomyolysis secondary to narcotic overdose. Key Point:

0Contraumatic causes of rhabdomyolysis include drug use, metabolic disorders, and infections.

0$his patient most li!ely has rhabdomyolysis, which is caused by s!eletal muscle damage that leads to release of intracellular components into the circulation, such as creatine !inase and lactate dehydrogenase, the heme pigment myoglobin, purines, and potassium and phosphate. $he syndrome was first identified in patients with traumatic crush in1uries, but t here are nontraumatic causes, such as alcohol 4due to hypophosphatemia5, drug use, metabolic disorders, and infections. $he classic triad of findings includes muscle pain, wea!ness, and dar! urine. $he diagnosis is based on c linical findings and a history of predisposing factors 4such as prolonged immobilization or drug toicity5 and confirmed by the presence of myoglobinuria, an increased serum creatine !inase level, and, in some c ases, hyper!alemia. $he disorder usually resolves within days to wee!s. $reatment consists of

aggressive fluid resuscitation; fluids should be ad1usted to maintain the hourly urine output at least 7 m9 until the urine is negative for myoglobin. Acute !idney in1ury resulting from acute tubular necrosis occurs in approimately one third of patients. Bialysis is sometimes necessary.

0 Although fulminant hepatic failure may result in coma, dar! urine, and renal failure, other tests of synthetic liver function in this patient are normal. $here are no clinical features to suggest sepsis. $he patient has mild anemia, but the proportionate reduction in the leu!ocyte and platelet counts suggests alcohol-induced bone marrow suppression. Hemolytic anemia would not eplain the patientEs elevated creatine !inase level and usually does not cause renal failure. Hemolytic uremic syndrome is not c onsistent with the clinical findings of polysubstance overdose or the laboratory finding of the elevated serum creatine !inase level.

(17)

Question 8

A +-year-old man is evaluated in the emergency department for a 2-day history of dyspnea with eertion, orthopnea, and paroysmal nocturnal dyspnea. He has ischemic heart disease with left ventricular dysfunction and had c oronary artery bypass graft surgery 6 wee!s ago. His medications include aspirin, nitroglycerin, metoprolol, lisinopril, and furosemide.#n physical eamination, the patient is sitting upright and breathing with difficulty; the temperature is 7+ J% 4?8.6 J'5, the blood pressure is *">8" mm Hg, the pulse rate is *">min and regular, and the respiration rate is 28>min. #ygen saturation is 8? on ambient air. $here are fine crac!les at the lung bases bilaterally, and breath sounds are diminished at the right b ase. $here is a regular tachycardia and an &7 at the ape. $here is no 1ugular venous distention or peripheral edema. Hemoglobin is *2."

g>d9 4*2" g>95, and the leu!ocyte count is *,">K9 4*." M *?_{>95. %hest radiograph shows cardiomegaly and small bilateral pleural effusions, greater on the right than the}

left. $horacentesis is performed, and pleural fluid analysis shows

0Cucleated cell count=">K9 with 7 neutrophils, + lymphocytes, * macrophages, *" mesothelial cells, and 2 eosinophils. 0Dleural fluid to serum total protein ratio ."=

09actate dehydrogenase 49BH5 *2" F>9

0Dleural fluid to upper limits of normal serum 9BH ratio ."2 0lucose 8 mg>d9 4=.== mmol>95

0$otal protein 7.+ g>d9 47+ g>95 0Dh +.="

0 Albumin *." g>d9 4*" g>95 0%holesterol 7" mg>d9 4.? mmol>95

0$he serumpleural fluid albumin gradient is *.+. hich of the following is the most li!ely diagnosis/ 0A- 8eart )ailure

0B- arapneumonic e))usion 0C- ost1cardiac inury syndrome 0D- ulmonary embolism

(18)

Answer and Critique 8

(Correct Answer:

A)

Educational Objective: %ecogni&e the effect of diuretic therapy on the pleural fluid analysis in patients with heart failure. Key Point:

0Biuretic therapy for heart failure c an result in either a protein- or l actate dehydrogenasediscordant eudative pleural effusion and, rarely, a concordant eudate.

0$he patientEs pleural fluid analysis shows a protein discordant eudate 4an eudate by protein criterion only5 with a pleural fluid to serum total protein ratio of ."= and a pleural fluid l actate dehydrogenase 49BH5 to upper limits of normal serum 9BH ratio of ."2. Dleural fluid findings may have eudative characteristics in patients with heart failure who are receiving diuretics. A serumpleural fluid albumin gradient greater than *.2 suggests a transudate in cases where the pleural fluid to serum total protein ratio or pleural fluid to serum 9BH ratio and pleural fluid 9BH to upper limits of normal serum 9BH ratio suggest an eudate, but the clinical findings suggest a transudate. $he increased pleural fluid to serum total protein ratio is the result of a diuretic effect, with more efficient clearance of pleural liuid than pleural protein.

0Datients with postcardiac in1ury syndrome typically present 7 wee!s 4range 7 days to * year5 after coronary artery bypass graft surgery; they usually have pleuritic chest pain and typically dyspnea, pleural or pericardial friction rub, fever, left lower lobe infiltrates, leu!ocytosis, and an increased erythrocyte sedimentation rate. $his patientEs findings are not compatible with postcardiac in1ury syndrome. $he absence of chest pain would be highly unli!ely with a pulmonary embolisminduced pleural effusion. Co

consolidation was detected on chest radiograph, ma!ing pneumonia unli!ely. 'urthermore, a parapneumonic effusion is typically a concordant eudate 4both protein and 9BH in the eudate range5 with a neutrophil predominance, and a low pleural fluid 9BH is typically not associated with an acute parapneumonic effusion.

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Question 9

A 2-year-old woman is ev aluated in the emergency department for an acute episode of wheezing and dyspnea

without cough or sputum production. &he has had previous freuent evaluations in emergency departments and

urgent care centers for similar episodes. 3n between these episodes, findings on physical eamination and

pulmonary function testing, including methacholine challenge, have been normal. &he is otherwise healthy and

ta!es no medications.

#n physical eamination, the patient has inspiratory and epiratory wheezing and is in moderate discomfort. $he

temperature is 7+.* J% 4?8.8 J'5, pulse rate is *>min, and the respiration rate is 2=>min; oygen saturation on

ambient air is ?6. After receiving albuterol and intravenous corticosteroids, she continues to wheeze and is in

moderate respiratory distress. #ygen saturation on ambient air remains at ?6. %hest radiograph shows

decreased lung volumes.

hich of the following is the most appropriate management for this patient/

0A-Chest C( scan

0B-Intra!enous aminophylline

0C-Intra!enous azithromycin

0D-Intra!enous terbutaline

0E-Laryngoscopy

(20)

Answer and Critique 9

(Correct Answer:

E)

Educational Objective: Evaluate vocal cord dysfunction. Key Point:

09aryngoscopy during an eacerbation of vocal cord dysfunction shows adduction of the vocal cords during inspiration.

0$his patient li!ely has vocal cord dysfunction 4)%B5. Datients with )%B can have throat or nec! discomfort, wheezing, stridor, and aniety. $he disorder can be difficult to differentiate from asthma; however, affected patients do not respond to the usual asthma therapy. Biagnosing )%B is made more difficult by the fact that many of these patients also have asthma. $he chest radiograph in this patient showed decreased lung volumes, which is in contrast to hyperinflation that would be epected in acute asthma. #ygen saturation is typically normal in patients with )%B.

09aryngoscopy, especially when done while the patient is symptomatic, can reveal characteristic adduction of the vocal cords during inspiration. Another test that helps ma!e the diagnosis is flow volume loops, in which the inspiratory and epiratory flow rates are recorded while a patient is as!ed to ta!e a deep breath and then to ehale. 3n patients with )%B, the inspiratory limb of the flow volume loop is NflattenedO owing to narrowing of the etrathoracic airway 4at the level of the vocal cords5 during inspiration. ecognition of )%B is essential to prevent lengthy courses of corticosteroids and to initiate therapies targeted at )%B, which include speech therapy, relaation techniues, and treating such underlying causes as aniety, postnasal drip, and

gastroesophageal reflu disease.

03ntravenous aminophylline is not recommended for treating either acute asthma or )%B. $herapy with intravenous terbutaline or other :-agonists for asthma eacerbations is associated with an unacceptably high rate of side effects. Azithromycin is a

reasonable choice for acute bronchitis, but there is little evidence that this patient has acute bronchitis, which would manifest with cough, sputum production, and fever. $he chest %$ scan can be used to eclude parenchymal lung disease or evaluate the possibility of a pulmonary embolism; however, these disorders are unli!ely in this patient with previous normal pulmonary eaminations and radiographs and ecellent oygenation, and chest %$ scan is unli!ely to yield useful information.

(21)

Question 10

0 A +2-year-old woman is evaluated for fatigue and decreased eercise capacity. $he patient has severe

chronic obstructive pulmonary disease, which was first diagnosed * years ago, and was hospitalized for

her second eacerbation * month ago. &he is a former smo!er, having stopped smo!ing " years ago. &he

has no other significant medical problems, and her medications are albuterol as needed, an inhaled

corticosteroid, a long-acting bronchodilator, and oygen, 2 9>min by nasal cannula.

0 #n physical eamination, vital signs are normal. @reath sounds are decreased, and there is *L bilateral

pitting edema. &pirometry done * month ago showed an '()

*

of 28 of predicted, and blood gases

measured at that time 4on supplemental oygen5 showed pH +.=*, D%#

2

=7 mm Hg, and D#

2

6= mm Hg;

B9%o is 7 of predicted. $here is no nocturnal oygen desaturation. %hest radiograph at this time shows

hyperinflation. %$ scan of the chest shows homogeneous distribution of emphysema.

hich of the following would be the most appropriate management for this patient/

0 A-ung transplantation

0 B-Lung !olume reduction surgery

0 C-,octurnal assisted !entilation

0 D-ulmonary rehabilitation

(22)

Answer and Critique 10

(Correct

Answer: D)

Educational Objective: Prescribe pulmonary rehabilitation for a patient with severe chronic obstructive pulmonary

disease.

Key Point:

0Dulmonary rehabilitation in patients with advanced lung disease can increase eercise capacity, decrease dyspnea,

improve uality of life, and decrease health care utilization.

0$his patient who is on maimum medical treatment for chronic obstructive pulmonary disease 4%#DB5 and is still

symptomatic would benefit from pulmonary rehabilitation. %omprehensive pulmonary rehabilitation includes patient

education, eercise training, psychosocial support, and nutritional intervention as well as the evaluation for oygen

supplementation. eferral should be considered for any patient with chronic respiratory disease who remains

symptomatic or has decreased functional status despite otherwise optimal medical therapy.

0Dulmonary rehabilitation increases eercise capacity, reduces dyspnea, improves uality of life, and decreases health

care utilization. eimbursement for pulmonary rehabilitation treatment remains an impediment to its widespread use.

0$he effect of lung volume reduction surgery is larger in patients with predominantly nonhomogeneous upper-lobe

disease and limited eercise performance after rehabilitation. $he ideal candidate should have an '()

*

between 2

and 7" of predicted, the B9%# no lower than 2 of predicted, hyperinflation, and limited comorbidities. $here is no

indication for nocturnal assisted ventilation because she does not have daytime hypercapnia and worsening oygen

desaturation during sleep. 9ung transplantation should be considered in patients hospitalized with %#DB eacerbation

complicated by hypercapnia 4D%#

2

greater than " mm Hg5 and patients with '()

*

not eceeding 2 of predicted and

either homogeneous disease on high-resolution %$ scan or B9%# less than 2 of predicted who are at high ris! of

death after lung volume reduction surgery. 9ung transplantation is, therefore, not an option for this patient.

(23)

Question 11

0 A +*-year-old woman is evaluated for a 7-wee! history of mild pain in the shoulders and thighs and wea!ness

when rising from a seated position and getting out of bed. &he also has a new rash on her hands. (ight m onths

ago she was evaluated for dyspnea and new interstitial infiltrates that resulted in a lung biopsy and a diagnosis

of idiopathic nonspecific interstitial pneumonia. &he was treated with prednisone, 6 m g>d, for * month; the dose

was then tapered to * mg>d. Her symptoms had been stable on that dose until her new complaints.

0 #n physical eamination, there are swelling and discoloration of the eyelids and an erythematous scaly rash

over the etensor surfaces of interphalangeal 1oints of both hands. $here is symmetric wea!ness of the proimal

hip fleors and shoulder girdle muscles; hand s trength is normal. 9aboratory studies show antinuclear antibodies

positive at a titer of 28 4previously negative5, serum creatine !inase *2+ F>9, and erythrocyte

sedimentation rate 6 mm>h; serum electrolytes and complete blood count are normal. %hest radiograph shows

bilateral reticular and alveolar abnormalities in the lower- and mid-lung zones.

hich of the following is the most appropriate management for this patient/

0 A-Electromyography and muscle biopsy

0 B-#epeat lung biopsy

0 C-$&in biopsy

(24)

Answer and Critique 11

(Correct

Answer: A)

Educational Objective: Diagnose and manage dermatomyositis presenting as interstitial lung disease. Key Point:

0Fp to 7 of patients with dermatomyositis and polymyositis present with single-organ involvement of the lungs indistinguishable from idiopathic interstitial lung disease.

0$his patientEs symmetric proimal muscle wea!ness and pain with an erythematous, scaly rash over the interphalangeal 1oints 4ottron sign5, coupled with a positive antinuclea r antibody titer and elevated creatine !ina se level, suggest

dermatomyositis. (lectromyography and muscle biopsy will establish the diagnosis of inflammatory myopathy. 3nflammatory myopathy must be distinguished from corticosteroid-induced myopathy because treatment of dermatomyositis reuires increased corticosteroids, whereas corticosteroid-induced myopathy is treated with withdrawal of prednisone. %orticosteroid-induced myopathy is not associated with elevated antinuclear antibodies, creatine !inase, or erythrocyte sedimentation rate. Fp to 7 of patients with dermatomyositis and polymyositis present without muscle, s!in, or 1oint involvement and have single-organ involvement of the lungs indistinguishable from idiopathic interstitial lung disease. 3nterstitial lung disease associated with inflammatory myopathy often occurs in the contet of antisynthetase antibodies 4for eample, anti-Po-*5 and the antisynthetase syndrome 4acute onset, constitutional symptoms, aynaud phenomenon, NmechanicEs hands,O arthritis, and interstitial lung disease5.

0epeat lung biopsy is unli!ely to yield new diagnostic information in this patient with stable chest radiograph and no new respiratory symptoms. A s!in biopsy is li!ely to reveal non specific findings that will not h elp diagnose the muscle symptoms.

(25)

Question 12

A +=-year-old man is evaluated for a "-year history of gradually progressive dyspnea and dry cough without wheezing or hemoptysis. 'or the past 2 years he has had pain and occasional swelling in both !nees. He has not had fever or lost weight. He smo!ed one pac! of cigarettes a day from the age of *8 to 6 years. He wor!ed as an insulator for = years.

Dhysical eamination shows no digital clubbing or cyanosis. Auscultation of the lungs reveals bilateral end-inspiratory crac!les. Dulmonary function testing shows

0$otal lung capacity 6+ of predicted 0esidual volume +2 of predicted 0')% 6" of predicted

0'()* +" of predicted

0'()*>')% ratio 8?

0B9%# "2 of predicted 0His chest radiograph is shown

hich of the following is the most li!ely diagnosis/ 0A-Asbestosis

0B-Idiopathic pulmonary )ibrosis 0C-#heumatoid interstitial lung disease 0D-ulmonary sarcoidosis

(26)

Answer and Critique 12

(Correct

Answer: A)

Educational Objective: Diagnose asbestosis. Key Point

0Dleural plaues are focal, often partially calcified, fibrous tissue collections on the parietal pleura and are a mar!er of asbestos eposure. 0$he diagnosis of asbestosis is based on a convincing history of asbestos eposure with an appropriately long latent period 4* to *" years5 and definite evidence of interstitial fibrosis without other li!ely causes. $his patient wor!ed as an insulator when asbestos eposure was still widespread and is at ris! for asbestos-related lung disease. $he most specific finding on chest radiograph is bilateral partially calcified pleural plaues. Dleural plaues are focal, often partially calcified, fibrous tissue collections on the parietal pleura and are considered a mar!er of asbestos eposure. 0heumatoid lung disease has many manifestations, including an interstitial lung disease, which is most common in patients with severe rheumatoid arthritis. $his patientEs occasional swelling in both !nees is not compatible with the diagnosis of rheumatoid arthritis.

0&arcoidosis occurs most commonly in young and middle-aged adults, with a pea! incidence in the third decade. <ore than ? of patients with sarcoidosis have lung involvement. $he chest radiograph may show hilar lymphadenopathy alone, hilar lymphadenopathy and reticular opacities predominantly in the upper lung zone, or reticular opacities without hilar lymphadenopathy. Dulmonary function tests may reveal a restrictive pattern and reduction in B9%#, or may be normal. $he patientEs age, predominantly lower lobe involvement, occupational history, and pleural plaues argue against pulmonary sarcoidosis.

03diopathic pulmonary fibrosis presents with slowly progressive dyspnea and a chronic, nonproductive cough. $he chest radiograph is almost always abnormal at the time of presentation, with decreased lung volumes and basal reticular opacities. Almost all patients have a physiologic restrictive process 4decreased forced vital capacity, total lung capacity, functional residual capacity5 as well as impaired gas echange with a decreased B9%#. However, asbestosis is a much more li!ely diagnosis in a patient with a positive eposure history and radiographic evidence of pleural plaues.

(27)

Question 13

0 A +"-year-old woman with a history of chronic obstructive pulmonary disease is evaluated

in the intensive care unit for delirium. &he had a median sternotomy and repair of an aortic

dissection and was etubated uneventfully on postoperative day =. $wo days later she

developed fluctuations in her mental status and inattention. hile still in the intensive care

unit, she became agitated, pulling at her lines, attempting to climb out of bed, and as!ing to

leave the hospital. Her arterial blood gas values are normal. $he patient has no history of

alcohol abuse. $he use of freuent orientation cues, calm reassurance, and presence of

family members has done little to reduce the patientEs agitated behavior.

hich of the following is the most appropriate therapy for this patientEs delirium/

0 A-Diphenhydramine

0 B-8aloperidol

0 C-Lorazepam

(28)

Answer and Critique 13

(Correct

Answer: B)

Educational Objective: 'reat delirium in the intensive care unit. Key Point

0Co drug is F.&. 'ood and Brug Administrationapproved for the treatment of delirium, but clinical practice guidelines recommend antipsychotic agents, such as haloperidol.

0hen supportive care is insufficient for prevention or treatment of delirium, symptom control with medication is occasionally necessary to prevent harm or to allow evaluation and treatment in the intensive care unit. $he appropriate treatment for this patient is haloperidol. $he recommended therapy for delirium is antipsychotic agents, although no drugs are F.&. 'ood and Brug Administrationapproved for this indication. #ngoing randomized, placebo-controlled trials are investigating different management strategies for intensive care unit delirium. A recent systematic evidence review found that the eisting limited data indicate no superiority for second-generation antipsychotics compared with haloperidol for delirium. Haloperidol does not cause respiratory suppression, which is one reason that it is often used in patients with hypoventilatory respiratory failure who reuire sedation. All antipsychotic agents, and especially NtypicalO agents such as haloperidol, pose a ris! of torsades de pointes and etrapyramidal side effects as well as the neuroleptic malignant syndrome.

0Biphenhydramine and other antihistamines are a ma1or ris! factor for delirium, especially in older patients. 9orazepam is actually deliriogenic, and its use in a delirious patient should be carefully re-evaluated, other than perhaps in patients eperiencing benzodiazepine withdrawal or delirium tremens. $here is no evidence that propofol has any role in treating delirium.

(29)

Question 14

A A 6-year-old woman is evaluated 7 wee!s after starting continuous positive airway pressure 4%DAD5

therapy for obstructive sleep apnea. $he patient was initially evaluated for ecessive sleepiness, and

obstructive sleep apnea was diagnosed based on results of polysomnography. 3t was determined that %DAD

at a pressure of *= cm H

2

# normalized respiration and oygen saturation during sleep. &he was prescribed

%DAD at this pressure along with heated humidification administered via a nasal mas!. &he has been using

%DAD, but she is still often sleepy during the day. &he has a history of hypertension and osteoarthritis, and

her medications are hydrochlorothiazide and ibuprofen. &he does not smo!e or drin! alcohol.

#n physical eamination, she is afebrile; the blood pressure is *=">8" mm Hg, and the @<3 is 76.". &he

has a slightly receding 1aw; otherwise, physical features are unremar!able.

hich of the following is the most appropriate net step in the management of this patient/

0A-rder a multiple sleep latency test

0B-rescribe hormone replacement therapy

0C-rescribe moda)inil

(30)

Answer and Critique 14

(Correct

Answer: D)

Educational Objective: Manage obstructive sleep apnea. Key Point

0(cessive sleepiness that persists despite positive airway pressure therapy may be due to poor adherence with treatment. 0#bstructive sleep apnea is associated with significant, even life-threatening complications, and %DAD is effective therapy. %DAD therapy reduces the number of apneas and hypopneas and improves sleep architecture, hypertension, and uality of life. (cessive sleepiness that per sists despite %DAD therapy may be due to poo r adherence with treatment, insufficient sleep duration, presence of coeisting sleep disorders, surreptitious use of sedating medications, or mood disorders. Adherence to %DAD therapy is often suboptimal, and many patients remain symptomatic and report either not being able to tolerate the device or using it intermittently. )erifying proper use and adherence is important before %DAD therapy is discontinued or additional studies are ordered or therapy prescribed. <any %DAD devices have data cards or meters that monitor use, and they can be evaluated to determine whether %DAD use is suboptimal.

0 A multiple sleep latency test can be performed if daytime sleepiness persists in a patient who is consistently able to use %DAD set at an optimal pressure; in this patient it will ob1ectively confirm her complaints of sleepiness but will not aid in identifying its cause. &timulant and wa!e-promoting agents, such as caffeine or modafinil, may be used as ad1unct therapy to improve residual daytime sleepiness in patients receiving optimal %DAD therapy, but should not be used as a substitute for proper %DAD use. &imilarly, hormone replacement therapy is not indicated as sole therapy for postmenopausal women with obstructive sleep apnea.

(31)

Question 15

A 28-year-old man is evaluated for a ?-month history of daily cough productive of yellow sputum and

intermittent low-grade fever. He has had three episodes of pneumonia during that time; the symptoms

improve with antibiotic therapy but return when therapy is disc ontinued. $he patient does not have a history

of aspiration, asthma, or sinusitis, and he ta!es no medications. He has never smo!ed.

#n physical eamination, the temperature is 7+.= J% 4??.7 J'5, the pulse rate is 88>min, the respiration rate

is *8>min, the blood pressure is **6>"8 mm Hg, and the @<3 is 2=. @reath sounds are reduced in the ri ght

base; the lungs are otherwise clear. 9aboratory tests are normal. $wo chest radiographs 7 months apart

have shown an infiltrate in the ri ght lower lobe. %ontrast-enhanced %$ scan of the chest shows right lower

lobe bronchiectasis and partial volume loss of this lobe; endobronchial obstruction is suggested. $here is no

lymphadenopathy.

hich of the following is the most li!ely diagnosis/

0A-Adenocarcinoma

0B-Carcinoid tumor

0C-$mall cell carcinoma

0D-$2uamous cell carcinoma

(32)

Answer and Critique 15

(Correct

Answer: B)

Educational Objective:%ecogni&e a typical presentation of a carcinoid tumor. Key Point

0%arcinoid tumors are neuroendocrine tumors with an indolent growth pattern that often present w ith endobronchial obstruction.

0 A carcinoid tumor is the most li!ely tumor in a young person who has never smo!ed and who has evidence of endobronchial obstruction. @ronchial carcinoid is a slow growing tumor that originally was classified as an adenoma but has been reclassified as a malignant neoplasm because of its ability to metastasize. <ost bronchial carcinoid tumors are located in proimal airways and cause symptoms by either obstructing an airway or bleeding. %ommon presenting symptoms include cough or wheeze, hemoptysis, and recurrent pneumonia in the same pulmonary lobe. $he carcinoid syndrome is caused by systemic release of vasoactive substances such as serotonin, and the most typical features include cutaneous flushing and diarrhea. @ronchial carcinoids are not commonly associated with the carc inoid syndrome because of their relatively small amount of serotonin production.

0 Although adenocarcinoma is the most common cancer cell type in a never-smo!er, it rarely causes endobronchial obstruction. &mall cell and suamous cell cancers freuently cause bronchial obstruction but rarely, if ever, occur in a young, never-smo!er. 'urthermore, the development of bronchiectasis denotes a chronic process of airway obstruction and infection. 3t occurs most commonly in association with foreign body aspiration, endobronchial obstruction by an indolent tumor such as carcinoid tumor, or secondary to etraluminal compression. %arcinomas, including those causing endobronchial obstruction, tend to grow very uic!ly, resulting in patient treatment 4or death5 before t hey can cause focal bronchiectasis. $reatment of carcinoid tumor is surgical resection when possible, and, for typical carcinoids, "-year survival is about ?.

(33)

Question 16

A 28-year-old man is A 7-year-old medical resident is evaluated for cough, right-sided chest pain, and fever of 2* daysE duration. He has no significant medical history or family history, and he ta!es no medications.

0Hemoglobin is *= g>d9 4*= g>95, and the leu!ocyte count is 8 >K9 48 M *?_{>95. %hest radiograph shows a right pleural effusion occupying}

approimately " of the hemithora without other abnormalities. $horacentesis yields turbid, yellow fluid, and analysis shows 0(rythrocyte count ">K9

0Cucleated cell count 7">K9 47." M *?_{>95 with 2 neutrophils, 6 lymphocytes, * macrophages, = mesothelial cells, and 6}

eosinophils

0$otal protein =.2 g>d9 4=2 g>95 09actate dehydrogenase 2= F>9 0Dh +.7"

0lucose 68 mg>d9 47.8 mmol>95

0&erum total protein is +. g>d9 4+ g>95 and serum lactate dehydrogenase is * F>9. ram stain shows no organisms and culture is pending.

hich of the following is the most appropriate net step in management/ 0A-Chest C( scan

0B-"le3ible bronchoscopy 0C-leural biopsy

(34)

Answer and Critique 16

(Correct

Answer: C)

Educational Objective: Evaluate a tuberculous pleural effusion. Key Point

0 A patient with tuberculous pleural effusion typically presents with a lymphocyte-predominant eudative effusion; however, within the first * to 2 wee!s, neutrophils can predominate as the cellular response evolves from neutrophils to lymphocytes.

0$he patient li!ely has a tuberculous pleural effusion based on the subacute 47-wee!5 duration of symptoms and the characteristics of the pleural effusion. @ecause of the patientEs age and the presentation with an isolated pleural effusion, primary tuberculosis is most li!ely. A tuberculous effusion is typically eudative by both protein 4pleural fluid to serum protein ratio greater than ."5 and lactate dehydrogenase 49BH5 criteria 4pleural fluid to serum 9BH ratio greater than .6 and pleural fluid to serum upper limits of normal 9BH ratio greater than .6+5. $he cellular response in the pleural fluid is classically lymphocytic 4greater than 8 mature lymphocytes5. However, it can be neutrophilic within the first 2 wee!s, after which it typically evolves into the classic lymphocyte-predominant eudate. hereas pleural fluid cultures for Mycobacterium are positive in less than one third of cases, the combination of pleural biopsy for histologic evaluation and culture is typically positive in more than two thirds of cases.

0$he 7-wee! history of symptoms is too long for a typical bacterial pneumonia, no definite infiltrate was present on the chest radiograph, and the cellular response in the pleural fluid was primarily lymphocytic rather than neutrophilic. $herefore, a bacterial pneumonia with a parapneumonic effusion is unli!ely, and an empiric course of azithromycin would not be appropriate. %hest %$ scan might be helpful to assess whether there is an underlying parenchymal infiltrate that was not visible on plain chest radiograph, but it would not help in determining the underlying cause of the pleural effusion. 'leible bronchoscopy, with collection of samples for histology and culture, is useful for diagnosing pulmonary tuberculosis in the setting of pulmonary parenchymal disease. However, the yield from culture of bronchopulmonary secretions 4obtained either as sputum or bronchoscopic samples5 is low, especially in the absence of pulmonary parenchymal abnormalities on chest radiograph.

(35)

Question 17

A 28-year-old man is eva luated in the emergency department for a 2-day history of worsening dyspnea a nd

wheezing in con1unction with an up per respiratory tract infection. $he patient has a history of asthma, and his

medications are inhaled mometasone and albuterol. 3n the emergency department, the patient is anious and is

using accessory muscles to breathe; he cannot spea! in full sentences. $he oygen saturation is ? while he

is breathing ambient air. @reath sounds are reduced bilaterally, with faint diffuse epiratory wheezes. He is given

albuterol by nebulizer, and use of accessory muscles is reduced. @edside spirometry shows an '()

*

of 7" of

predicted; he is given two more treatments of nebulized albuterol.

After treatmen t, the patient is alert with slight use of a ccessory muscles; he can spea! in sho rt full sentences.

)ital signs are stable; oygen saturation is ?8 with the patient receiving oygen, 2 9>min. @reath sounds are

louder than on initial eamination, and wheezing is more intense. &pirometry shows an '()

*

of " of

predicted.

hich of the following is the most appropriate net step in the management of this patient/

0A-Admit the patient to a regular medicine ward

0B-Discharge the patient on his baseline asthma treatment regimen

0C-Intubate and admit the patient to the intensi!e care unit

(36)

Answer and Critique 17

(Correct

Answer: A)

Educational Objective: Manage a patient with an exacer bation of asthma.

Key Point

0$he response to inhaled bronchodilators is more predictive of the clinical course in a patient with asthma than initial

physical eamination and findings.

0$his patient presented with signs of a severe asthma eacerbation. Becreased breath sounds, accessory muscle use,

sternocleidomastoid or suprasternal retractions, inability to spea! in full sentences, and paradoical pulse greater than

*" mm Hg are associated with severe airflow obstruction, although the absence of these findings does not necessarily

eclude the presence of a high-ris! eacerbation. However, the initial physical eamination and findings are less

predictive of the clinical course in a patient with asthma than the response to bronchodilators. $his patient has

responded well to bronchodilators, with improved ability to spea! and reduced accessory muscle use. heezing may

become more prominent in the early stages of recovery owing to improved airflow through narrowed airways. According

to the newest Cational Asthma (ducation and Drevention DrogramEs guidelines, admission to the intensive care unit is

recommended for symptomatic patients with even mild carbon dioide retention 4D%#

2

greater than =2 mm Hg5 or

severely decreased lung function despite aggressive bronchodilator treatment 4persistent '()

*

or pea! epiratory flow

less than = of predicted5. $his patient does not meet the criteria for admission to the intensive care unit or intubation

and mechanical ventilation at this time. $he best disposition for this patient would be admission to the hospital ward; his

'()

*

has not improved enough to warrant discharge.

(37)

Question 18

A 6"-year-old man is admitted to the intensive care unit for gram-negative sepsis. $he patientEs

medical history is significant only for hyperthyroidism for which he ta!es methimazole. #n day 2 in

the intensive care unit, he undergoes rapid seuence intubation with propofol and succinylcholine

for worsening hypoemic respiratory failure resulting from the acute respiratory distress syndrome.

$he patient receives intermittent lorazepam and fentanyl boluses intravenously for sedation.

&everal hours later, the patient becomes febrile 4temperature = J% Q*= J'R5, hypertensive, and

tachycardic. #n eamination, he is diaphoretic and has muscular rigidity. Arterial blood gas analysis

shows a metabolic and respiratory acidosis, and laboratory results are significant for an elevated

serum creatine !inase level.

hich of the following is the most li!ely cause of the patientEs clinical deterioration/

0A-4alignant hyperthermia

0B-,euroleptic malignant syndrome

0C-$erotonin syndrome

(38)

Answer and Critique 18

(Correct

Answer: A)

Educational Objective:Diagnose malignant hyperthermia. Key Point

0<alignant hyperthermia is an inherited s!eletal muscle disorder characterized by a hypermetabolic state precipitated by eposure to volatile inhalational anesthetics and the depolarizing muscle relaants.

0$his patient most li!ely has malignant hyperthermia, which is an inherited s!eletal muscle disorder characterized by a hypermetabolic state precipitated by eposure to volatile inhalational anesthetics 4halothane, isoflurane, enflurane, desflurane, sevoflurane5 and the depolarizing muscle relaants succinylcholine and decamethonium. 3t usually occurs on eposure to the drug but can occur several hours after t he initial eposure and can develop in patients who were previously eposed to the drug without effect. 3ncreased intracellular calcium leads to sustained muscle contractions, with s!eletal muscle rigidity and masseter muscle spasm, tachycardia, hypercarbia, hypertension, hyperthermia, tachypnea, and cardiac arrhythmias. habdomyolysis and acute renal failure c an develop. <alignant

hyperthermia should be suspected in patients with a family history of problems during anesthesia.

0$he neuroleptic malignant syndrome is a life-threatening disorder caused by an idiosyncratic reaction to neuroleptic tranuilizers 4dopamine B2-receptor

antagonists5 and some antipsychotic drugs. $he most common offending neuroleptic agents are haloperidol and fluphenazine. $he syndrome occurs with all drugs that cause central dopamine receptor bloc!ade, usually soon after starting a new drug or with dose escalation. 3t has been reported in patients with Dar!inson disease who abruptly discontinue levodopa or anticholinergic therapy. <ost patients with the syndrome develop muscle rigidity, hyperthermia, cognitive changes, autonomic instability, diaphoresis, sialorrhea, seizures, arrhythmias, and rhabdomyolysis within 2 wee!s after initiating the drug. @ecause this patient did not receive a neuroleptic agent, neuroleptic malignant syndrome is unli!ely. 3n critical care patients receiving both neuroleptic tranuilizers and depolarizing muscle relaants, malignant hyperthermia can be differentiated from neuroleptic malignant syndrome by the presence of a mied 4metabolic and respiratory5 acidosis in the former condition.

09i!e the neuroleptic malignant syndrome, the serotonin syndrome presents with high fever, muscle rigidity, and cognitive changes. 'indings uniue to the serotonin syndrome are shivering, hyperrefleia, myoclonus, and ataia. $he serotonin syndrome is caused by the use of selective serotonin reupta!e inhibitors, a category of drug that this patient has not been eposed to.

0$hyroid storm is a potential cause of hyperthermia in hospitalized patients, but thyroid storm does not cause muscle rigidity or elevations of the creatine !inase level.

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