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Flashcards in First Aid: Respiratory Deck (71):

In which cases does FRC increase?

Advanced Age and Asthma Attack


Shifting the O2 dissociation curve to the right will _________ unloading of O2 in the tissue?



What increases unloading of O2 in the tissues (i.e. shifts O2 dissociation curve to the right)?

Increases in BAT ACE
BPG, Altitude, Temperature, Acid, CO2, Exercise


What are the normal concentrations of pH, PCO2, and bicarbonate in arterial blood?

pH: 7.35-7.45
PCO2: 40 mmHg
bicarbonate: 22-28 mmol/L


Where are the relative levels of ventilation and perfusion in the apex and base of the lung?

BOTH V and Q are increased at the base of the lung. But V/Q is higher at the apex.


A patient presents with increased sinus congestion and complains of tenderness in the region of his maxillary sinuses. What is his disease and what are the top 4 common causes of it?


1. Viral upper respiratory tract infection
2. S. Pneumoniae
3. H. influenzae
4. M. catarrhalis


A 50 y/o woman recently arrived from a long flight from Australia. She is currently battling breast cancer and has a history of smoking and high cholesterol. She complains of calf pain on dorsiflexion of the foot. What would you opt to treat her with in an acute and long term setting? (also describe the 3 major risk factors for her disease)

May have Deep Vein Thrombosis (Virchow's Triad: 1. Stasis, 2. Hypercoagulability -commonly factor V Leiden- 3. Endothelial damage)

Tx: Heparin for acute management, Warfarin for long term DVT management


What are the common causes of a shunt, and how can you detect its presence?

AV malformation or consolidated pneumonic lobule.

Give pure O2 to breath and notice how PAO2 will not increase as much as it should.


Patient presents with cyanosis and chocolate-colored blood. What does he have and what would you treat him with? What do you NOT want to give the patient?

Methemoglobinemia (oxidized form of Hb, w/ decreased affinity for O2 and increased affinity for cyanide)

Give Methylene blue. DO NOT give Nitrites.


How can you treat cyanide Poisoning?

Give nitrite to oxidize Hb to methemoglobin (which binds cyanide). Thiosulfate to bind this cyanide --> Thiocyanate --> Renal excretion


What is the normal level of Hb in your blood, and when would you develop cyanosis?

Normal: 15 g/dL
Cyanosis: deoxygenated Hb > 5 g/dL


A 58 year old man with a 40 pack year history presents with shortness of breath (increasing over past few years). He has some cough with little sputum and marked chest overexpansion. He is non-cyanotic with quiet breath sounds, hyperresonance on percussion, and he seems to be breathing through pursed lips. He is experiencing some weight loss as well. What would you expect to see on a gross specimen of his lungs, as well as on histological slides? What would happen to his FRC?

Pink Puffer - barrel shaped chest - emphysema - INCREASED FRC

Centracinar emphysema, multiple air space cavities lined by heavy black carbon deposits on gross specimen.

On microscopy, enlarged alveoli separated by thin septa.


Why does the chest wall expand with emphysema?

Increased elastase activity, loss of elastic fibers and increased lung compliance.

Lung isn't able to push in as readily and expands into chest wall (loses lung/chest wall tug of war).


A 32 year-old nonsmoker presents with shortness of breath and mild to very little cough (no sputum). He complains of loss of appetite, fatigue, and a brownish orange tint on his urine. He is jaundiced and shows signs of edema in legs and ankles. A liver biopsy is taken; what do you see? What genetic mutation may he have?

On biopsy you see round dark purple/pink (PAS+) globules in the hepatocytes (this is alpha-1 antitrypsin accumulation).

A1AT Deficiency - panacinar emphysema may also be present.


A 54 year old man with a 30 pack year history presents with SOB and frequent productive cough over the past 4 months. This has been occuring for some years now. He is cyanotic and you hear wheezing and rales on auscultation. You also notice some peripheral edema. What would you expect his Reid index to be on biopsy of bronchiole tissue? What would you possibly see on echocardiography?

>50%, from hyperplasia of mucus-secreting glands in bronchi

Right Ventricular Hypertrophy as a result of right heart failure. Cor pulmonale, because arterioles clamp down everywhere to shunt blood to well perfused regions. Now heart has to pump against increased pulmonary tension.


A 45 year old woman presents to the ER with shortness of breath and chest pain. She seems disoriented and confused and has signs of petechial rash. An ABG shows low oxygen levels. Her husband who is with her states that she has no major prior medical history, other than a recent liposuction that she received by a plastic surgeon from a local clinic. She was resting in bed for many days following surgery. What test should you do immediately? You see the tests results, what is she suffering from and what are other major causes for this?

CT pulmonary angiography to look for filling defects as a result of Pulmonary Embolism from a fat embolus

Causes include FAT BAT:
-Fat (following liposuction and long bone fractures)
-Air (nitrogen bubbles in ascending divers -need hyperbaric oxygen)
-Thrombus (DVT)
-Amniotic fluid (can lead to disseminated intravascular coagulation, especially post-partum)
Tumor (hypercoagulability)


What is the MOA of beta 2 agonists?

Increased adenalyl cyclase activity in the smooth muscles, increasing intracellular cAMP, decreasing muscle contraction


What three conditions are associated with Type I allergic hypersensitivity reaction of asthma?

1. Allergic Rhinitis
2. Eczema
3. Family History of Atopy


What are three non-allergenic causes of asthma?

1. Exercise
2. Viral URI
3. Aspirin intolerant asthma


A 2 year old is brought in because of difficulty breathing. The parents state that the child has had multiple bouts of a "cold" over the past year and now frequently breathes out of her mouth. Rhinoscopy reveals nasal polyps. What do you immediately want to screen the child for?

Cystic fibrosis


A 27 year old man who works on Wall Street presents to the ER with wheezing and SOB. He wasn't feeling well in the morning following a night of heavy drinking and decided to take something for his headaches. He was at a female friends house and took "something she had laying around". What drug did he take, and what would you find on physical exam?

He took aspirin triggering an asthmatic exacerbation as a result of aspirin intolerant asthma.

On PE or rhinoscopy you may find nasal polyps.


What are the key histopathological findings in someone with asthma, and how did these arise?

1. Smooth muscle hypertrophy
2. Curschmann spirals (shed epithelium forms mucous plugs)
3. Charcot-Leyden Crystals (from breakdown of eosinophils in sputum)


What are the key clinical symptoms in someone with asthma?

Wheezing, cough, tachypnea, dyspnea, hypoxemia, decreased I/E ratio, pulsus paradoxus, mucus plugging


A 63 year old smoker presents with difficulty on expiration. He is a severe cough, SOB, and produces a purulent sputum, with occasional traces of blood. Laboratory tests reveal a decreased PAO2. What does this patient have, how did it develop, and why is it so difficult to expire?


Damage to the walls of the airway (especially the cilia) as a result of chronic necrotizing infection of the bronchi. Smoking caused it in this case.

Resulting dilation of bronchi results in loss of tone and air trapping. Dilation of airways does not allow for the air to accelerate out.


What are the 5 main associations with bronchiectasis and the pathological processes that lead to this disorder?

Necrotizing Inflammation: In all cases the pathophysiology is a result of necrotizing inflammation following infections.

1. Smoking: reduced ciliary motility
2. Cystic fibrosis: big secretions and mucous plugging lead to increased infection
3. Kartagener Syndrome: Defective dynein arm of cilia (also have sinusitis, infertility and organ inversus)
4. Tumor or foreign body: airway block --> infection
5. Allergic bronchopulmonary aspergillosis: hypersensitivity reaction to aspergillus bug leading to inflammation of airway


An allergen activates the TH2 phenotype of CD4+ T cells in genetically susceptible individuals resulting in the secretion of certain factors. What are these factors and what do they in turn activate?

Pathophysio process of Asthma:

IL4 -> IgE activation
IL5 -> Eosinophils activated
IL10 -> increases TH2 and inhibits TH1 perpetuation disease


Re-exposure to an allergen that activated TH2 phenotype and led to immune response will cause what cascade of events, leading to early phase asthma exacerbation?

Early Phase: Crosslinking of MAST cells --> Histamine release --> 1) vasodilation, leaky capillaries 2) Leukotrienes C4, E4 -bronchoconstriction via sm. muscle contraction - D4 - increased vascular permeability- and overall vasoconstriction 3) increased vascular permeability


What compound perpetuates late phase bronchoconstriction in asthma?

Major Basic Protein


What effect do restrictive lung disease have on FVC, TLC, FEV1 and FEV1/FVC?

FVC, TLC, and FEV1 are decreased

FEV1/FVC > 80%


A patient presents with Dyspnea and rapid shallow breathing. The dyspnea worsens with exercise and the patient becomes cyanotic. He has an irritating non-productive cough and you notice some clubbing of the fingers. What is this person suffering from, and what stage of disease? What would happen to their PAO2 and CO2 levels and pH?

Interstitial Pulmonary Fibrosis in late stage of disease.

PAO2 and PACO2 would both decrease, pH remains normal


What drugs or medical treatments can lead to Interstitial lung disease?

Bleomycin, busulfan, amiodarone, methotrexate, Radiation Therapy


A 35 year old AA woman presents with breathlessness and dry cough. You notice erythema nodosum on the knees, uveitis, and enlarged parotic glands. What pathology would you see on a histological specimen? What key results would appear in serum samples?

Sarcoidosis (Stage 2)

Non-caseating granulomas, large histocytes, giant cells, and lymphocytes

Serum ACE would be elevated as well as Hypercalcemia


What happens to CO diffusion capacity when you have interstitial lung disease?

Major Reduction, because overall diffusion impairment


A 42 year old female veterinarian presents with dyspnea, cough, chest tightness and headache. What pathology would you notice on histological specimen?

Hypersensitivity pneumonitis (mixed type III/IV hypersensitivity reaction)

Small granulomas w/ exudate and eosinophils


What factors lead to pneumoconioses, and what pathophysiological process will lead to this?

Inhalation of 1) small particles, 2) w/ chronic exposure, 3) and fibrogenic immune response.

Macrophage mediated. MPh consumes particles and induces fibrosis all over lung to "wall off the garbage"


A 35 year old engineer presents breathlessness and dry cough. XRay demonstrates masses in the hilar lymph nodes of the lung. Biopsy reveals non-caseating granulomas. The patient had been completely fine for the past year, while she worked on a prototype for a new commercial jet. What is the cause of this pathology?

Berylliosis from beryllium inhalation.

(type of pneumoconiosis)


What are three main types of pneumoconioses, and what do these increase the risk of developing?

Coal worker's, silicosis, and asbestosis.

Increased risk of cor pulmonale, and Caplan syndrome (Rheumatoid arthritis and pneumoconioses with intrapulmonary nodules)


A 53 year old man who owns his own roof tiling business, presents with SOB and dry cough. CT shows ivory white calcified pleural plaques. What lobes of the lung are most likely affected and what would you see on pathological specimen?

Path would show Ferruginous bodies (golden brown fusiform "dumbell" rods).

Asbestos is "from the roof but affects the BASE of the lungs.


What is the most likely malignancy to develop from asbestosis? What is not as likely?

Cancer of the lung is most common.

Mesothelioma, cancer of the pleura, can also occur.


What is the only pneumoconiosis that increases the risk for TB? What pathophysiological process occurs in this disease?

Silicosis (sand blasters)

impairs phagolysosome to form in macrophages. Eggshell calcification of hilar lymph nodes.


Which pneumoconioses is most associated with Caplan Syndrome? What would their lung look like?

Coal workers lung from carbon dust.

Black shrunken lung


A patient presents with symptoms very similar to sarcoidosis, but there is no evidence of granulomas, what could this be?

Sjogren Syndrome (affects salivary and lacrimal glands)


What is the milder form of coal workers pneumoconioses that is usually reversible and benign?

Anthrocosis from sooty air exposure in urban dwellers. Carbon deposits in Macrophages


A 31 year old diabetic mother is giving birth to her first child via C-Section. He lecithin:sphingomyelin ratio in amniotic fluid is found to be

Neonatal respiratory distress syndrome (surfactant deficiency --> increased surface tension --> alveolar collapse)

Persistently low O2 tension can increase risk of patent ductus arteriosis. O2 supplement may cause retinopathy of prematurity and bronchopulmonary dysplasia

Tx: maternal steroids before birth, artificial surfactant for infant


What is the major component of surfactant? What is normal L:S ratio?

Phosphatidyl Choline (Lecithin)

L/S > 2


What can lead to hypercoagulability of blood?

Sickle Cell Disease
Polycythemia Vera
Oral Contraceptives
Recent Trauma


A 27 year old woman presents after experience shortness of breath and faintness following exercise. Her pulmonary pressure is found to be 30 mmHg at rest (Normal = 10-14, >25=HTN). What pathological and genetic abnormalities would you find? What may you see on echocardiography?

Primary Pulmonary Hypertension

Path: VASCULAR SMOOTH MUSCLE PROLIFERATION & PLEXiFORM LESIONS; arteriosclerosis, medial hypertrophy and intimal fibrosis of pulmonary arteries.

Genetic: BMPR2 inactivating mutation (familial)

Echo: RV hypertrophy


What are the main secondary causes of secondary hypertension and why?

1. COPD (destrunction of lung parenchyma)
2. Mitral stenosis (increased resistance --> increased pressure).
3. Recurrent thromboemboli (decreased cross sectional area of vascular bed)
4. Autoimmune disease (system sclerosis: inflammation, fibrosis)
5. Left to right shunt (endothelial injury from increased shear stress)
6. Sleep apnea or living at high altitude


A patient presents to the ER with severe respiratory distress and cyanosis. Echo reveals RV hypertrophy and eventually the patient expires from decompensated cor pulmonale. What was the most likely initial etiology for this case?

Pulmonary Hypertension


What are the three most important characteristics associated with pulmonary hypertension?

1. BMPR2 mutation
2. Plexiform lesions
3. Atherosclerosis of Pulmonary arteries


Describe the associated complications of lung cancer.

SPHERE of complications

Superior vena cava syndrome (distention of H/N veins)
Pancoast Tumor
Horner Syndrome (ptosis, pinpoint pupil, anyhdrosis)
Endocrine (paraneoplastic)
Recurrent laryngeal symptoms (hoarseness)
Effusions (pleural or pericardial)


A teenage boy presents with productive cough and dyspnea. He is unable to participate in the exercises at gym class and has a history of frequent infections. You also notice some clubbing of the fingers. What does he have, and what would happen to his FEV1, FEF25-75, RV and FRC? How would this effect elastic recoil?


FEV1 and FEV would decrease

RV and FRC would increase

Decreased elastic recoil


What are the 3 major risk factors for lung cancer?

1. Cigarettes (polycyclic aromatic Hydrocarbons + arsenic)
2. Radon
3. Asbestos (lung cancer>mesothelioma)


A 60 year old male with 40 pack year history presents with cough, weight loss, hemoptysis and post-obstructive pneumonia. You notice some hoarseness in his voice. What are important next steps, and what may you find on Chest XRay? What is the most likely cause of this?

Get chest X ray which may reveal solitary nodule of 2-5 cm, COIN LESION



On chest XRay of the 60 year old male patient with 40 pack year history, cough hemoptysis, and weight loss, you notice a solitary 3.4 cm hilar nodule arising from the bronchus. You also notice cavitations on radiography. What is the likely cancer type, what would you see on histology, and what serum findings may you have?


Histology: Keratin pearls (whorls) and intercellular bridges

Serum: Hypercalcemia from PTHrP production


A 37 year old woman presents with a benign lung lesion. What are the two most likely causes?

1. Granuloma: previous TB, fungal or histoplasmosis infection
2. Bronchial Hamartoma (lung tissue + cartilage)


What are the 2 main types of lung carcinoma and their Treatment protocols?

1. Small cell carcinoma (15%)
Tx = chemo "too small to see, can't do surgery"

2. Non-small cell carcinoma (85%)
Tx = Surgery


A 57 year old man with 50 pack year history presents with cough, chest pain and hemoptysis. A central mass is found and biopsied. It reveals small dark blue cells (neuroendocrine Kulchitsky cells). What is the overall prognosis, and what syndrome is associated with this?

SMALL CELL (OAT CELL) CARCINOMA - very aggressive, poor prognosis

ACTH, ADH, or Antibodies against presynaptic Calcium channels (Lambert-Eaton Myasthenic Syndrome)


What is the most common lung cancer in nonsmokers and female smokers? What are the characteristics of this cancer type?

Adenocarcinoma, peripheral, NO perineoplastic syndrome

Cancer of mucous glands. Tumor forms glandular shape w/ blue-grey mucous intracellularity

Activating mutations: k-ras, EGFR, ALK


What other medical condition is adenocarcinoma closely associated with?

Hypertrophic osteoarthropathy (clubbing)


Which two lung cancers have excellent prognosis, and where do these tumors originate from and what are some important characteristics?

Bronchioloalveolar subtype (adenocarcinoma in situ), grow along alveolar septae and give impression of alveolar wall thickening. CXR shows pneumonia like consolidation.

Bronchial Carcinoid tumor - Polyp-like mass, well differentiated nest of neuroendocrine cells, not mitotically active. Chromogranin positive.


Which lung cancer has the worst prognosis?

Large Cell Carcinoma (10%)

Poorly differentiated large cells w/ no characteristic histo signs. Smoking, central/peripheral


What is the most common type of tumor in the lung? What is their characteristic appearance on radiography?

Metastases from breast and colon carcinoma

multiple cannon-ball nodules


A patient presents with malignancy of the pleura associated with asbestosi. This results in hemorrhagic pleural effusions and pleural thickening. What does he have and what is seen on histology?


Psammoma bodies


Which form of emphysema predominately affects the apex of the lung?

Centriacinar emphysema


Which molecular mediators have a role in bronchoconstriction in asthma? What does not?

Histamine, Bradykinin, Leukotrienes, Interleukins



What are some key physical exam signs consistent with pulmonary embolism?

Pleuritic pain, hemoptysis, tachycardia, pleural friction rub


What affects do beta-adrenergic agonists have on airway resistance?



An elderly patient presents with fever, tachypnea, and a cough that produces currant jelly sputum. He has localized pain on his right side on inspiration, and you hear decreased breath sounds and dullness to percussion in this region. What would a sputum sample reveal and what would you notice on Chest XRay? What are other common causes of this disease?


Caused by Klebsiella (aspiration --> pneumonia)

Consolidation of Right lung (one or more lobes)

Most frequently from S. pneumoniae. Could also be legionella.


What are the main bugs that can cause bronchopneumonia, and how does this illness usually present?

S. pneumo, staph aureus, H. infleunzae, Klebsiella

Acute inflammatory infiltrates from bronchioles into adjacent alveoli. patchy distribution involving >1 lobe


A 28 year old AA male patient presents with nonproductive cough, low fever and sinus tenderness. A CXR reveals diffuse interstitial infiltrate w/o any major consolidation. On histological specimen you would see empty air sacs with lots of inflammatory cells in the interstitium. What is the most likely cause of this disease?

Interstitial (Atypical) pneumonia

1. Most commonly viral (flu in elderly or immunocompromised, RSV in infants, CMV in posttransplant, adenovirus).
2. Mycoplasma pneumo, most common in young adults (college or military)
3. Chlamydia 2nd most common in young adults
4. Coxiella (farmers and vets, high fever)