Pulmonology

What are the 2 types of pleural fluid that can accumulate in pleural effusions?

What are the 2 types of pleural fluid that can accumulate in pleural effusions?

1. transudate (protein-poor)

   1. fluid buildup d/t increased hydrostratic P OR decreased oncotic P

   2. CHF, NEPHORSIS, CIRRHOSIS

2. exudate (protein-rich)

   1. fluid buildup d/t abnml capillary permeability (BV damage) OR decreased lymphatic drainage

   2. INFX OR MALIGNANCY (CANCER)

What are the most common sxs of exudative pleural effusion?

dyspnea + hypoxemia

Which type of pleural effusion is associated w/ hemothorax?

exudative

What are some (rarer) primary causes of pleural effusion

• TB

• AI disease

• bleeding / chest trauma

• asbestos exposure

Why will whispering pectoriloquy produce a louder sound if the pt has a pleural effusion?

water is a better conductor of sound than air, so fluid-filled part of lung will make whisper sound louder

What is pleurodesis?

irritant is placed into pleural space (thoracoscopy or chest tube) → causes fibrous adhesions like velcro = no more fluid accumulates

• used for CHRONIC or SLOW TO RESOLVE pleural effusions

What is the nml amount of fluid in the pleural space?

~3-15mL (nml lymph drainage)

In thoracentesis, should the needle be inserted above or below the rib?

ABOVE - to avoid piercing the intercostal VAN (which is below the rib)

What is the utility of Light’s criteria in diagnosing pleural effusions?

can help differentiate which type of effusion (exudative vs. transudate)

What is Light’s criteria for exudative effusion?

• pleural fluid protein / serum protein ration > 0.5

• pleural fluid LDH / serum LDH > 0.6

• pleural fluid LDH = greater than 2/3 of nml upper limit

What is a parapneumonic effusion and how should you treat them?

pleural effusion that accompanies bacterial PNA

• IF SIMPLE (small): do NOT drain … instead, tx underlying PNA w/ abx

• IF COMPLICATED (large/loculated/empyema): consider thoracentesis

For which patients is indwelling pleural catheter a good tx option (pleural effusion)?

pts w/ poor prognosis … this is b/c there is a long-term risk of infx

What is an empyema?

loculated collection of pus (like an abscess)

What is interstitial/restrictive lung disease?

category of diseases that cause irreversible fibrosis 2/2 alveolar epithelial cell injury

NO IDENTIFIABLE CAUSE

What are some Ddx to asthma? (“all that wheezes is not asthma”)

• allergic rhinitis

• GERD

• COPD

• sinusitis / PND

• FBO

How can you ID a pneumothorax on XR?

areas of black space (no white streaks/vasculature)

For which conditions might you see a tracheal shift (away from the affected side) on XR?

• massive pleural effusion

• tension pneumothorax

What are “honeycomb lungs” on chest CT?

thickened cystic spaces in lung walls; indicative of SEVERE IPF (idiopathic pulmonary fibrosis)

What is Lofgren vs. Heerfordt syndrome?

both are clinical presentations of sarcoidosis (you can dx W/O A BX)

LOFGREN

• b/l hilar adenopathy

• erythema nodosum, fever, arthralgia

HEERFORDT

• ant. uveitis

• parotitis, fever, facial nerve palsy

What are the prognoses/outcomes for sarcoidosis involving lung parenchyma, skin, hilar adenopathy?

• hilar only = BEST

• skin involvement = GOOD

• lung parenchyma = WORSE

What is Virchow’s triad?

1. venous stasis

2. endothelial injury

3. hypercoagulability

CONTRIBUTING FACTORS THAT FORM A PE

What is a saddle embolus?

PE that forms at the bifurcation of main pulmonary artery → then travels distally + gets stuck in a branch of the artery

What kinds of PE thrombi are likely to cause pulmonary infarction + pleuritis?

SMALLER thrombi located DISTALLY

What effects in the body does a PE cause (what is the pathophysiologic response)?

1. infarct (10%)

   • pleuritic CP

   • hemoptysis

2. abnml gas exchange

   • V/Q mismatch = intrapulmonary shunt (ventilated but NOT perfused)

   • resp. alkalosis

   • hypoxemia (low PO2)

   • hypocapnia (low PCO2)

3. CV compromise

   1. hypotension

   2. increased pulmonary vascular resistance

   3. decreased CO

What is an intrapulmonary shunt?

an area of the lung that is VENTILATED (air goes through) but NOT PERFUSED (no gas exchange)

What is Wells Criteria?

diagnostic criteria for PE

• 0-1 pts: LOW risk

• 2-6 pts: MODERATE risk

• >6 pts: HIGH risk

If you have a patient with profound hypoxia and nml CXR, what diagnosis should you have a high suspicion for?

PE

What is the primary tool for dx of PE?

chest CTA (CT angiography)

… NOT PLAIN CHEST CT!!

What are contraindications to CTA?

• kidney problems (CKD or acute kidney injury)

• IV contrast dye allergy

  • relative contraindication; depends on severity of rx

• asthma

  • relative contraindication; needs premedication protocol

• heart failure

• pregnancy

  • do V/Q first (CTA still may be needed)

For what conditions does pneumoconiosis increase risk of?

• TB

• fungal infx

• COPD

• chronic bronchitis

• AI DZ

• CKD

• lung cancer (asbestos mesothelioma)

Define: FEV1, FVC

• FEV1 = amnt of air someone can forcefully exhale in 1 second

• FVC = amnt of air someone can forcefully exhale in 1 breath

What is the nml range of values for FEV1/FVC ratio?

0.75-0.85

What is the difference b/t obstructive and restrictive lung disease?

• restrictive - pts cannot INHALE fully

  • nml FEV1/FVC

• obstructive - pts cannot EXHALE fully

  • decreased FEV1/FVC

What are 4 examples of obstructive lung disease?

1. asthma

2. COPD

3. bronchiectasis

4. CF

What are the 2 types/categories of restrictive lung disease?

1. intrinsic (ie. INTERSTITIAL LUNG DISEASE)

2. extrinsic (ie. obesity, pleural effusion, scoliosis)

What results on spirometry will indicate asthma? (2 possible methods)

1. after baseline, 12% improvement s/p bronchodilator therapy

2. positive methacholine challange test (causes airway spasm) = FEV1 drops 20%

   • NOT FOR EVERYONE, CAN BE DANGEROUS

     • pregnant/nursing

     • recent MI/stroke

     • aneurysm

     • FEV1 <65%

What are the 2 goals of asthma tx/management?

1. optimize control

2. prevent future flares (by optimizing pharmacotherapy)

What are the 2 categories of asthma medications?

1. quick relievers — directly relax bronchiole smooth muscle; used PRN + for exercise-induced

2. long term controllers — decrease inflammation; used daily

What are 5 classes of asthma medications?

1. bronchodilators

   • beta2 agonists: SABA (albuterol) or LABA

   • muscarinic agents: SAMA (ipratropium) or LAMA

2. steroids

   • inhaled corticosteroids (fluticasone, budesonide, mometasone)

   • systemic steroids (prednisone, methylprednisone)

3. mast cell stabilizers

4. leukotriene modifiers

   • montelukast

5. methylxanthines

What are the 2 standards that exist for selecting asthma meds?

1. NAEPP - everyone gets a SABA; spirometry/peak flow will determine asthma severity

2. GINA - severity is based on sxs frequency; no spirometry; no step 1 SABA

What does well-controlled asthma look like?

• daytime sxs or reliever use: 2x/wk

• nighttime awakening (d/t sxs): 2x/mo

• peak flow + spirometry nml

• PO steroids or UC visit: 1x/yr

What does a-antitrypsin deficiency cause?

• lung related

• liver = cirrhosis

• skin = panniculitis

Define chronic bronchitis

productive cough x 3mo in 2 consecutive years

Define emphysema and clinical findings that support the dx

abnml permanent enlargement of alveoli/airspaces (associated w/ COPD)

• “blebs” / apical bullae on CXR or CT

What is the gold standard for COPD dx?

PFT

A decrease in DLCO (on PFTs) indicates what type of COPD?

emphysema

What are the GOLD levels/stages for COPD?

1. mild … FEV1 >80%

2. moderate … FEV1 50-80%

3. severe … FEV1 30-50%

4. VERY severe … FEV1 <30%

Should you use inhaled/IV/PO steroids as pharmacological monotherapy for COPD?

NO!

What are the goals of COPD tx?

1) help prevent + manage exacerbations

2) relieve sxs

3) slow progression

4) reduce morbidity + mortality

What posible pharmacological therapies are available for COPD?

• bronchodilators

• steroids

• abx

• PDE-4 inhibitor

• theophylline

What is a common cause/trigger of COPD exacerbation?

RESPIRATORY INFXS (70%) from bacteria or viruses

• S. pneumonia

• H. influenza

• M. catarrhalis

• P. aeruginosa

How should mild vs. moderate vs. severe COPD exacerbations be treated?

• mild - short bronchodilator (SABA or SAMA)

• moderate - SABA or SAMA + abx (may add PO steroid)

• severe - ER visit or hospitalization

What 3 sxs define a moderate or severe exacerbation of COPD?

1. increased dyspnea

2. increased sputum volume

3. increased sputum purulence

Is it acceptable to start a COPD pt on prophylactic abx therapy?

YES (prophylaxis for frequent exacerbations)

What is the definition/criteria for hemodynamically UNstable PE?

results in hypotension

• systolic BP <90
  OR

• systolic BP drops at least 40mmHg x 15min
  OR

• vasopressor required

Why is it important to distinguish b/t hemodynamically stable vs. unstable PE?

UNstable PE has more risks:

• more likely to die from obstructive shock

• death usually w/in first 2hrs

What is the most common source of PEs?

proximal DVT from LE

In what kind of pts are upper extremity PE’s seen?

• pts w/ cancer

• pts w/ central venous catheter

What is the greatest risk factor for PE?

immobility (ie. hospitalization, stroke, obesity, heavy smoking, spinal cord injury, total joint replacement)

Why is it important to maintain a high level of clinical suspicion for PE?

SXS VARY A LOT and many pts are ASXS (even w/ large PE)

therefore sxs are NOT specific for PE

What ABG findings are diagnostic for PE?

ABG IS NOT DIAGNOSTIC FOR PE!!!!

supportive findings:

• respiratory alkalosis

• hypoxemia (low PO2)

• hypocapnia (low PCO2)

• abnml A-a gradient

When/Why would you order D-dimer labs for possible PE pts?

order for low/moderate risk pts in order to determine if you should get IMAGING for them

• <500 ng/mL = most likely NO PE

• >500 ng/mL = maybe PE → further workup

What venous US findings are supportive for PE/DVT?

• inability to compress femoral/popliteal veins = likely DVT

• full compression b/l = likely NO DVT

What 2 CXR signs are supportive for PE?

• Westermark — central pulm a. w/ low blood flow (“cuts off”)

• Hampton’s hump — “wedge-shaped defect” opacity (= hemorrhage + infarct)

other: atelectasis, effusion, infiltrates

How does a V/Q scan work?

1. VENTILATION: pt inhales radiolabeled gas → then see how gas is distributed in lungs

2. PERFUSION: pt is injected w/ radiolabeled IV albumin → then see blood flow to lung

What types of anticoagulants can be used for PE?

• heparin — fractionated (low molecular weight) vs. unfractionated

• vit K antagonist

  • warfarin/coumadin) — use w/ IV heparin

• direct oral a/c (DOAC)

  • apixaban (eliquis) — monotherapy

  • rivaroxaban (xarelto) — monotherapy

  • dabigatran (pradaxa) — use w/ IV heparin

  • edoxaban (savaysa) — use w/ IV heparin

How do unfractionated heparins work (in the setting of PE tx)?

PREVENTION (rather than a true tx)

• binds to antithrombins (inactivate clotting factors) = SLOWS DOWN FURTHER CLOT FORMATION

How do you treat PE w/ UNfractionated heparin?

1. IV heparin

   • NOT subQ — this is only for prophylaxis

2. 3-6mo of PO warfarin

3. monitor labs (CBC, PT, APTT, INR, heparin induced thrombocytopenia)

What is the #1 complication of anticoagulant therapy?

hemorrhage/bleeding — monitor closely w/ labs, ESP IF:

• kidney DZ (adjust DOAC dose)

• foods (warfarin)

• other medications (drug-drug interactions)

What are the benefits/drawbacks of thombolytic therapy (TPA, streptokinase, urinokinase)?

• PRO: directly lyse clots = faster resolution of thrombi

• CON: greater risk of big bleeds

THEREFORE USE ONLY FOR unstable PE, hemodynamic instability, R heart strain (per echo)

What are the advantages of fractionated heparin (low molecular weight heparins AKA LMWH) over unfractionated?

• lower risk of bleeding

• lower risk of heparin induced thrombocytopenia

• dose is based on body weight (qD or BID)

• can be home-based tx

Why are DOACs preferred over VKAs (warfarin)?

• fewer drug interactions

• drug level monitoring is NOT needed

In what pts are DOACs contraindicated?

pts w/ hepatic DZ & coagulopathy

What is normal mean pulm artery pressure (mPAP) & how do you measure it?

~14mmHg

measured by R heart catheterization

What are the 5 classes of pulmonary HTN?

1. idiopathic or other cause

   • idiopathic: poor prognosis (only one)

2. 2/2 L heart failure

3. 2/2 lung DZ or hypoxia

4. chronic thomboembolic pulmonary HTN (or 2/2 other pulm a. obstructions)

5. unclear or multifactorial cause

What is the most important prognostic factor in all cases of pulmonary HTN?

RV function

Is RV a better VOLUME pump or PRESSURE pump?

VOLUME — can adapt better to changes in PRELOAD (vol) than AFTERLOAD (resistance)

What are some diagnoses that pulmonary HTN can be secondary to?

• HIV/AIDS

• anorexigenic drugs

• connective tissue disorder

• L heart failure

• hepatitis/cirrhosis

• sleep apnea

• other lung problems

What are the goals of pulmonary HTN tx?

reduce vasoconstriction + cellular proliferation

How is the size of a SPN related to risk of malignancy?

• 2-5mm … 1%

• 6-10mm … 24%

• 11-20mm … 33%

• 21-45 … 80%

What are the 2 methods available for biopsy of a SPN?

1. bronchoscopy

   • lower diagnostic yield

   • not very good for small peripheral nodules

2. TTNA (transthoracic needle aspiration)

   • higher diagnostic yield BUT HIGHER FALSE NEGATIVE

   • higher risk of complications (ie. pneumothorax)

Who should receive an annual low-dose radiation CT scan (screening for lung cancer)?

• ages 50-80 w/ 20+ pack-yr smoking hx

  • who currently smoke OR quit less than 15yrs ago

What is a LUNG-RADS classification?

LUNG imaging CT Reporting And Data System

• included w/ low-dose CT report — classifies the lung condition

What are the 4 histologic subtypes of non-small cell lung cancer (NSCLC)?

1. squamous cell carcinoma

2. adenocarcinoma

3. adenocarcinoma in situ

4. large cell carcinoma

What is a paraneoplastic syndrome?

organ dysfx caused by neoplasms (via immune system or secretory effects)

What lung cancers can cause paraneoplastic syndromes?

• small cell LC → SIADH = hyponatremia

• squamous cell LC → hypercalcemia

• small cell LC & bronchial carcinoids → ectopic ACTH secretion

• small cell LC → Eaton-Lambert Myasthenic Syndrome (mimics myasthenia gravis)

• any → clubbing, anemia, peripheral neuropathy

What kind of tumors can cause a false negative read on PET scan?

tumors w/ low metabolic activity

• carcinoid tumors

• minimally invasive

What lung cancer is the most common in smokers? (presents as intraluminal mass)

SCC

What lung cancer arises from epithelial cell near terminal bronchioles OR mucus glands — presents as peripheral nodule/mass?

adenocarcinoma

What lung cancer is spread along alveolar structures and has no invasion?

adenocarcinoma in situ

What lung cancer is a misc. group of aggressive tumors (fast doubling times)?

LCC (large cell carcinoma)

What lung cancer causes bronchi narrowing, is very aggressive, + metastasizes (usually via blood)?

SMALL CELL LUNG CANCER

What is SVC syndrome?

lung tumor blocks SVC flow = R sided face/neck swelling

• ONCOLOGIC EMERGENCY … urgent radiation therapy

What is Horner syndrome?

• ptosis, miosis, anhidrosis

• pancoast tumor

What is a pancoast tumor?

adenocarcinoma in superior lung

What is carcinoid syndrome?

• flushing

• diarrhea

• wheezing

• hypotension

What are characteristics of a person w/ latent TB infx?

• NOT contagious + no sxs

• positive TB skin/blood test

• should be treated still to prevent transition into active TB disease

What are risk factors for TB?

KNOWN OR POTENTIAL exposure to mycoplasma TB:

• born in OR recent travel to countries where TB is common

• health care workers

• workers/residents of homeless shelters, jails, nursing homes

IMMUNOCOMPROMISED

• HIV

• substance abuse

• silicosis

• cancer

How do you read a TB skin test?

>5mm is (+) for:

• HIV

• recent exposure

• organ transplants, immunocompromised

>10mm is (+) for:

• born in countries where TB is common

• substance abuse

• occupational risk

• low body weight

>15mm is (+) for: everyone else

How do you treat latent TB infx?

• isoniazid AKA INH (+ vitB6) … 300mg qD x 9mo

  • monitor for hepatotoxicity (check liver enzymes)

  • d/c if LFTs are 3xNML w/ sxs OR 5xNML

• isoniazid + rifampin … x 3mo

• rifampin … x 4mo

REFER TO PULM