Week 3 Flashcards
Learning Objectives: Describe the salient radiographic and histologic features of the varying idiopathic interstitial pneumonias. (MKS 1d, 3a). Explain the prognosis and treatment options for patients with IPF. (MKS 3a)
A 55 year old male presents with several months of a non-productive cough and dyspnea on exertion. He smokes about three or four packs of cigarettes per week and has done so for about 40 years. You order a CT scan to evaluate for potential lung cancer but instead find bronchial wall thickening, ground glass opacities, and centrilobular nodules. Which of the following is the best treatment option for this patient?
- Corticosteroids.
- Supportive.
- Nintedanib or pirfenidone.
- Complete smoking cessation.
- Lung transplantation.
Answer: D
- Corticosteroids. These could be used in NSIP, COP, and sometimes AIP.
- Supportive. For the IIPs, this is the mainstay of care only in AIP.
- Nintedanib or pirfenidone. These are antifibrotic therapies for IPF.
- Complete smoking cessation. The chronic presentation and CT findings are consistent with RBILD and DIP, for which the treatment is smoking cessation.
- Lung transplantation. This can prolong survival and improve quality of life in carefully selected patients with IPF.
177a: Pleural Disorders
Learning Objectives: List the signs and symptoms of a pneumothorax and understand the mechanisms by which pneumothoraces develop and are treated. MKS1b, 1e. Describe the clinical signs and symptoms of pleural disease and be able to recognize pleural effusions and pneumothoraces on chest radiographs and CT scans. MKS1b, 1d
In the ER, you see a previously healthy 22-year old male bicyclist who has been hit by a car. He is conscious but having chest pain when breathing. His vitals are: RR 30, BP 80/55, HR 160. On physical exam, you notice the right side of his chest is hyperresonant to percussion. You obtain a chest xray. Which of the following is the next best step?
- Call orthopedic surgery to reduce rib fractures.
- Intubation.
- Watchful waiting, as pneumothoraxes tend to be reabsorbed.
- IV blood cultures from two sites and then empiric antibiotic therapy.
- Immediate drainage of the pleural space with a needle or chest tube.
Answer: E
- Call orthopedic surgery to reduce rib fractures. Despite radiographic evidence of rib fracture (the likely cause of the pneumothorax), the more pressing issue is the circulatory collapse, which needs to be addressed first.
- Intubation. This is not an appropriate treatment for tension pneumothorax, as mechanical ventilation will not fix the pressure issues caused by the pneuomox thorax.
- Watchful waiting, as pneumothoraxes tend to be reabsorbed. While this is true of small pneumothoraxes, large ones causing cardiovascular issues are life-threatining and need immediate treatment.
- IV blood cultures from two sites and then empiric antibiotic therapy. This would be appropriate if you suspected sepsis, which is unlikely to be the cause of this patient’s poor vital signs.
- Immediate drainage of the pleural space with a needle or chest tube. This patient has a tension pneumoxthorax, as evidenced by the precipitious vital signs, hyperresonance, and free air on the CXR. Tension pneumothorax require immediate decompression to remedy the circulatory collapse.
Learning Objective: Distinguish between an exudate and transudate using Light’s criteria and know the causes of transudative effusions.MKS1b
On your interventional radiology rotation, you perform thoracentesis on several patients over the course of a day. The first result to come back from the lab shows a pleural fluid LDH to serum LDH ratio of 0.45 and a pleural fluid to serum protein ratio of 0.72. Which of the following patients does this lab result belong to?
- The 70-year old female with CHF admitted for an episode of acute decompensation.
- The 45-year old male with alcoholic liver cirrhosis awaiting a transplant.
- The 50-year old female with previously diagnosed primary breast cancer.
- The 42-year old male with acute nephrotic syndrome.
- The 53-year old female with poorly controlled hypothyroidism.
Answer: C
- The 70-year old female with CHF admitted for an episode of acute decompensation. CHF can cause transudative effusions by increasing the microvascular hydrostatic pressure.
- The 45-year old male with alcoholic liver cirrhosis awaiting a transplant. Cirrhosis can cause transudative effusions by decreasing the microvascular osmotic pressure.
- The 50-year old female with previously diagnosed primary breast cancer. Primary and metastatic neoplasms in the lung can cause exudative pleural effusions due to leaky or inflamed pleural membranes. Breast cancer is one that can commonly metastasize to the lung.
- The 42-year old male with acute nephrotic syndrome. Nephrotic syndrome can cause transudative effusions by decreasing the microvascular osmotic pressure.
- The 53-year old female with poorly controlled hypothyroidism. Hypothyroidism can cause transudative effusions.
No learning objectives were provided
You are seeing a 60-year old male with progressive dyspnea on exertion, fatigue, and a complex medical history. What is the most common cause of pulmonary hypertension?
- Pulmonary artery hypertension (WHO Type I).
- Left heart disease (WHO Type II).
- Lung disease (WHO Type III).
- Thromboembolic disease (WHO Type IV).
- Unknown (WHO Type V).
Answer: B
- Pulmonary artery hypertension (WHO Type I). US prevalence about 5,000
- Left heart disease (WHO Type II). US prevalence in the millions.
- Lung disease (WHO Type III). US prevalence more than 200,000
- Thromboembolic disease (WHO Type IV). US prevalence about 90,000
- Unknown (WHO Type V).
No learning objectives were provided
A 60-year old woman undergoes a lengthy diagnostic process after experiencing nearly two years of dyspnea on exertion and fatigue. She is ultimately diagnosed with pulmonary artery hypertension. Which of the following is the best treatment option for this patient?
- Start sildenafil.
- Start furosemide.
- Start warfarin.
- Start corticosteroids.
- Refer for thromboendarterectomy.
Answer: A
- Start sildenafil. Vasodilators are the class of drug of choice for pulmonary arterial hypertension.
- Start furosemide. This might be a treatment option for pulmonary hypertension due to left heart disease, for optimizing the management of the heart disease through diuresis.
- Start warfarin. This is a treatment option for pulmonary hypertension due to chronic pulmonary embolism.
- Start corticosteroids. If the patient had an underlying lung disease responsible for the pulmonary hypertension and corticosteroids would improve the disease, then this would be the answer.
- Refer for thromboendarterectomy. This is a treatment option for pulmonary hypertension due to chronic pulmonary embolism.
Learning Objectives: Describe the most common risk factors for PE. (MKS 1a,b,d). Describe both the acute and long-term management of PE. (MKS 1d)
A 55-year-old woman with a history of schizophrenia and metastatic breast cancer presented several days ago to the emergency department with paranoia and active hallucinations. Her agitation was so severe that she had to be restrained for several days. She was started on haloperidol. Now, you are seeing her as an inpatient, when overnight she became tachycardic and started complaining of sharp right-sided chest pain. On exam, she has bilateral lower extremity edema, but the right calf appears to be more swollen and tender than the left. While proceeding with the diagnostic workup, what step should be taken next in the care of this patient?
- Discontinue the haloperidol.
- Start a β-blocker.
- Start broad-spectrum antibiotics.
- Start intravenous heparin.
- Watchful waiting.
Answer: D
- Discontinue the haloperidol. While antipsychotics increase the risk of PE, ceasing the medication would not treat the PE.
- Start a β-blocker. This would just provide symptomatic relief of the tachycardia, and is not an appropriate step.
- Start broad-spectrum antibiotics. There is nothing in this presentation to suggest infection.
- Start intravenous heparin. This patient has a Well’s score of at least 7 (3 DVT signs and symptoms, 1.5 tachycardia, 1.5 immobilization, 1 malignancy, +/- 3 PE likely as alternative diagnosis), indicating a likely PE. In patients with a high pre-test probability of PE, anticoagulant therapy should be started immediately while awaiting the results of diagnostic testing.
- Watchful waiting. This is not appropriate in a patient with a high pre-test probability of a PE.
Learning Objectives: Describe how an assessment of pre-test probability informs subsequent diagnostic testing in suspected PE. (MKS 1a,b,d)
A 70 year old male with a history of DVT and lymphoma presents at the ER with pleuritic chest pain, shortness of breath, and blood tinged sputum. In his chart, you read that he has an ECOG score of 3 (Capable of only limited selfcare; confined to bed or chair more than 50% of waking hours). Vitals are temperature of 98.9F, heart rate of 106 bpm, and a respiratory rate of 20. On exam, you note that breath sounds absent from left lung base. An EKG reveals sinus tachycardia and right ventricular strain. The patient is started empirically on low molecular weight heparin. However, his D-dimer then comes back negative. Which of the following is most accurate?
- The negative predictive value of D-dimer for this patient is 97%.
- The negative predictive value of D-dimer for this patient is much less than 97% due to the higher pre-test probability given this patient’s Well’s score.
- The specificity of D-dimer is very high so PE is unlikely.
- The positive predictive value of D-dimer is very high so PE is unlikely.
Answer: B
- The negative predictive value of D-dimer for this patient is 97%. The NPV of a D-Dimer is only 97% in patients with a Well’s score of = 4.
- The negative predictive value of D-dimer for this patient is much less than 97% due to the higher pre-test probability given this patient’s Well’s score. This patient has a Well’s score of 9.5 (3 PE more likely than other diagnosis, 1.5 immobilization, 1.5 tachycardia, 1 hemoptysis, 1.5 previous DVT, 1 cancer). This patient probably should have received diagnostic imaging without waiting for a D-dimer, as the pre-test probability of PE is so high that even a negative D-dimer would not have reduced the post-test probability of PE.
- The specificity of D-dimer is very high so PE is unlikely. The specificity of a D-dimer is not great, as several other conditions can lead to elevated D-dimers, such as age, inflammation, trauma, pregnancy, and malignancy. However, a D-dimer is highly sensitive.
- The positive predictive value of D-dimer is very high so PE is unlikely.
Learning objective. Describe the relationship between PaCO2, serum bicarbonate and pH, MSK1a,d
A 33-year old female is visiting her primary care physician. She tells him that she is generally doing well but that she occasionally has panic attacks, characterized by a feeling of impending doom, chest pain, lightheadedness, and hyperventilation. You know from your studies that when a patient hyperventilates, the ___________ in minute ventilation can cause an acute __________ in the blood pH.
- Decrease, decrease.
- Decrease, increase.
- Increase, decrease.
- Increase, increase.
Answer: D
- Decrease, decrease. Hyperventilation can increase minute ventilation (respiratory rate x tidal volume).
- Decrease, increase. Hyperventilation can increase minute ventilation. Decreased minute ventilation increases PaCO2, which decreases the blood pH.
- Increase, decrease. Hyperventilation can increase minute ventilation, but increases in minute volume decrease PaCO2, which increases the pH of the blood.
- Increase, increase. With increased minute ventilation, the patient is removing more CO2 from the lungs, resulting in a decreased PaCO2. Less CO2 (the acid component of the bloodstream buffer system) pushes the pH up towards an alkalosis.
Learning Objectives: Describe respiratory and metabolic compensation, MSK1a,d Calculate the anion gap and explain its importance in acid base disturbances, MSK1a,d, MSK3a
A 35-year-old male with a past medical history of poorly controlled Type 1 diabetes is brought to the ER after his friends found him confused, fatigued, breathing rapidly, and complaining of abdominal pain at home. Labs reveal a serum glucose level of 500 mg/dL (abnormally high), and his urine is positive for glucose and ketones. Which of the following sets of lab values are consistent with his presentation?
- Blood pH 7.2; PaCO2 20; Na 135; Cl 118; HCO3 8.
- Blood pH 7.2; PaCO2 20; Na 135; Cl 100; HCO3 8.
- Blood pH 7.2; PaCO2 40; Na 135; Cl 118; HCO3 8.
- Blood pH 7.2; PaCO2 40; Na 135; Cl 118; HCO3 8.
Answer: B
- Blood pH 7.2; PaCO2 20; Na 135; Cl 118; HCO3 8. This set of labs is consistent with a non-anion gap metabolic acidosis with expected respiratory compensation.
- Blood pH 7.2; PaCO2 20; Na 135; Cl 100; HCO3 8. This set of labs is consistent with an elevated anion gap metabolic acidosis with expected respiratory compensation. This patient is presenting with diabetic ketoacidosis, which causes an anion gap metabolic acidosis. To compensate, he is hyperventilating, resulting in a lowered PaCO2.
- Blood pH 7.2; PaCO2 40; Na 135; Cl 118; HCO3 8. Similar to A, but additionally there is no decrease in PaCO2, as would be expected in a hyperventilating patient with DKA.
- Blood pH 7.2; PaCO2 40; Na 135; Cl 118; HCO3 8. Similar to B, but in this case, there is no decrease in PaCO2, as would be expected in a hyperventilating patient with DKA.
Learning Objective: Explain the pathophysiology of asthma. MKS1b
An 8-year-old boy comes to the physician with his mother, who wants to discuss respiratory problems that have arisen since an upper respiratory infection 4 months ago. The mother says that the patient has attacks characterized by wheezing and shortness of breath that usually resolve after an hour. On one occasion, an attack required a visit to the emergency department, and the mother remembers that the patient was prescribed an albuterol rescue inhaler in case an attack happened again. Which of the following cytokines plays a key in the pathogenesis of the underlying disease?
- Interferon-γ.
- Interleukin-2.
- Interleukin-4.
- Tumor necrosis factor−α.
- Tumor growth factor−β.
Answer: C
- Interferon-γ. This would be more common in a Th1 response.
- Interleukin-2. This would be more common in a Th1 response.
- Interleukin-4. This child likely has asthma. In the airway, mast cells release IL-4 and IL-5 which promote the formation of more mast cells and the differentiation of Th2 lymphocytes, which contribute to the chronic nature of the disease.
- Tumor necrosis factor−α
- Tumor growth factor−β
Learning objective: Describe the development of COPD MKS 1b
A 50 y/o M with a 15 pack year history of smoking complains of increased shortness of breath over the past several months. On physical exam he has an increased chest diameter, pursed lips, and is leaning forward with his elbows on his knees. Lungs are hyperresonant to percussion. PFTs show a FEV1/FVC of 0.55. Yellowing of the skin and scleral ictus is noted. Lab values demonstrate a high AST and ALT. He denies any alcohol use. Which of the following could best explain these symptoms?
- An inherited genetic disorder.
- Asthma.
- Chronic bronchitis.
- Decreased elastase activity.
Answer: A
- An inherited genetic disorder. This patient is presenting with emphysema. Patients with the ZZ phenotype of alpha-one antitrypsin deficiency are unable to release alpha-one antitrypsin from the liver (and so the potential for liver failure) resulting in low levels of alpha-one antitrypsin in the blood and lung. Because alpha-one antitrypsin is a protective anti-protease, deficiency causes an imbalance between harmful proteases and protective anti-proteases resulting in lung damage.
- Asthma. This could cause the noted obstructive defect, but not the liver failure.
- Chronic bronchitis. This could cause the noted obstructive defect, but not the liver failure.
- Decreased elastase activity. Alpha-one antitrypsin normally decreases protease (including elastase) activity in the lung. Loss of this protein leads to increased proteolytic activity and tissue damage.
Learning objective: Describe the development of COPD MKS 1b
A 60-year old male with a 80 pack year history of smoking presents with 2 years of a productive cough and progressive shortness of breath. After much diagnostic testing, including spirometry which reveals a FEV1/FVC ratio of 0.6, he is diagnosed with COPD. Regarding the key disturbances in COPD, which of the following is true?
- Airway obstruction that completely improves with pharmacologic treatment is likely to be COPD.
- Only alveoli are affected by COPD.
- Short-term treatment aims to increase airway diameter using beta2 antagonists.
- Decreased parenchymal elasticity can increase expiratory effort.
- Genetic predisposition is the strongest predictor of COPD diagnosis. In the US, smoking history is a stronger predictor
Answer: D
- Airway obstruction that completely improves with pharmacologic treatment is likely to be COPD. COPD causes expiratory airflow obstruction that is not fully reversible by medications.
- Only alveoli are affected by COPD. COPD also causes small airway remodeling and increased mucus secretion.
- Short-term treatment aims to increase airway diameter using beta2 antagonists. Beta2 agonists are used in the treatment of COPD.
- Decreased parenchymal elasticity can increase expiratory effort. Destruction of lung tissue results in decreased elastic recoil and subsequent airway collapse, increasing expiratory effort and leading to the obstructive defect seen in COPD.
- Genetic predisposition is the strongest predictor of COPD diagnosis. In the US, smoking history is a stronger predictor
