Pulm/Peds Flashcards
Normal pH, PaCO2, and PaO2
7.4, 40, 100
Allen test
Check for upper extremity arterial perfusion by occluding both radial and ulnar aa
Metabolic acidosis causes
Increased anion gap: Lactic acidosis, Ketoacidosis, Drug poisoning (Aspirin, Ethylene glycol, Methanol) = MULEPAKS
Normal anion gap: HARDUP = Diarrhea, Renal tubular acidosis, Interstitial nephritis
Metabolic alkalosis causes
Cl- responsive: Contraction alkalosis, Diuretic use, Corticosteroids, Gastric suctioning or Vomiting
Cl- resistant: Hyperaldosterone state, Hyperventilation
Respiratory acidosis PaCO2 and pH
Low pH and High PaCO2
Respiratory alkalosis PaCO2 and pH
High pH and Low PaCO2
How can alveolar-arterial gradient show signs of lung problems
Alveolar-arterial oxygen gradient is ELEVATED when gas diffusion is impaired
A-a = Alveolar O2 (i.e. atmospheric O2) - arterial O2
Expected normal = Patient age/4 + 4A-a = 0.21(760 atm P - 47 tracheal water vapor P) - PaCO2/(0.8 respiratory quotient) - PaO2
Things limiting O2-Hb dissociation
Alkalosis
Hypothermia
Low PCO2
Low 2,3-DPG
Normal PaO2:FiO2
Dissolved to inhaled O2 ratio
On room air = 100/0.21 = ~475
Increasing FiO2 won’t fully correct hypoxia from a shunt, i.e. If a patient is on an oxygen canula, this should be much lower
Meaning of decreased and increased V/Q ratio
Decreased V/Q = better perfusion than ventilation = shunt (Emphysema, fibrosis, edema)
Increased V/Q = worse perfusion than ventilation = dead space (PE, trachea)
Most air and blood in lungs goes where?
Bases of lungs
Pulmonary function tests (PFTs)
Spirometry
Lung Volumes
Diffusing capacity
So why are PFTs useful?
Explain Dyspnea (Asthma vs VCD)
Hypoxemia etiology (COPD vs Vascular disease)
Follow disease over time (FVC test)
Pre-op testing
FEV1 definition, use
Forced expiratory volume in first second, used for FEV1/FVC ratio
Most reproducible flow rate measurement over time
Can give bronchodilator and repeat 15m later in asthma diagnostics
If FEV1/FVC less than 70% = OBSTRUCTION
Obstructive pulmonary diseases
Air can’t get out
Asthma, emphysema, chronic bronchitis
Restrictive pulmonary diseases
Air can’t get in (restrictive = reduced volume)
Pulmonary fibrosis, Hypersensitivity pneumonitis, Sarcoidosis, Silicosis, Neuromuscular (e.g. ALS)
Variable extrathoracic obstruction (laryngeal cancer) pulmonary cycle
Flattening of flow rate on inspiration
Variable intrathoracic obstruction (lung cancer) pulmonary cycle
Flattening of flow rate on expiration
Fixed obstruction (intra- or extrathoracic) pulmonary cycle
Flattening of flow rate on both inspiration and expiration
Tests for lung functional volume
Nitrogen washout and He dilution
COPD pattern of FVC vs TLC
Low FVC and High TLC
Diffusing capacity test, what affects it
DLCO: breathe in CO, see how much diffused in
DLCO = Kco * Va (Equilibrium CO coefficient * alveolar volume)
Membrane thickness, Lung volume, Air trapping, Carboxyhemoglobin
Stridor
Inspiratory sound from turbulent flow below or in the larynx
Extrathoracic obstruction, better with expiration
Stertor
Sound from turbulent flow above larynx (snoring)
Ronchi and crackles
Same sound
Alveoli popping open on inspiration due to fluid consolidation
Fine crackles = acute, pneumonia, edema
Velcro crackles = fibrosis
Rales and wheezes
Same sound
Musical expiratory sound from airway constriction
Intrathoracic obstruction
Improved by inspiration
Rub
Pleural sound on either inspiration or expiration
Due to fluid or fibrosis in pleura
To differentiate from cardiac rub, ask patient to change position or hold breath
Variable extrathoracic obstruction shows what on respiratory flow cycle?
Flat flow rate on inspiration
Variable intrathoracic obstruction shows what on respiratory flow cycle?
Flat flow rate on expiration
Bronchiolitis usually due to … ?
Treatment?
RSV
Supportive O2 and IV fluids
Croup pathophys, sound, causes
Laryngotracheitis
Seal-bark cough, hoarseness, stridor
Parainfluenza, RSV
What tests should be ordered for pediatric pneumonia outpatients?
Pulse ox, Flu testing, Mycoplasma IgM
Consider CXR in some circumstances
Blood cultures if patient deteriorates or doesn’t improve
COPD definition, diseases
Preventable and treatable disease with persistent airflow limitation and inflammation of airways
Umbrella term for progressive lung diseases like:
Emphysema - ‘pink puffer,’ thin, dyspnea
Chronic bronchitis - ‘blue bloater’ w/ elevated Hb
Irreversible asthma
Severe bronchiectesis
Pathophys of COPD
Small airway disease - inflammation, fibrosis, plugs = up resistance
Parenchymal destruction - alveolar walls destroyed
Most common COPD causes
Tobacco - question diagnosis w/o smoking in history
Occupational exposure
Also a1-antitrypsin deficiency
COPD symptoms
Shortness of breath
Chronic cough
Sputum
COPD diagnosis
Use spirometry tests - for detecting obstructive lung disease (COPD and asthma)
If FEV1/FVC is low, then obstructive disease
How low FEV1 is by itself determines severity
Restrictive disorder spirometry results
When to perform?
Low FVC, TLC, FEV1
But normal or high FEV1/FVC
Only perform outpatient when patient is stable
COPD comorbidities
CV disease Osteoporosis Respiratory infxn Anxiety, depression DM Lung cancer Bronchiectasis
Additional COPD tests besides spirometry
CXR - for excluding other diagnoses
Lung volumes, diffusing capacity - for determining severity
Oximetry, ABG - need for supplemental O2
a1-antitrypsin deficiency screening - Perform if under 45y or when strong FH of COPD
Exercise testing
COPD therapy - general, pharmacological, surgical
Smoking cessation and supplemental O2 (24h/d) most helpful
Exercise
Flu, pneumococcal vaccines
b2-agonists (1st for asthma)
Anti-cholinergics (1st for COPD)
Steroids
Lung volume reduction surgery
Lung transplantation
Reasons for COPD exacerbation
Infxn - give abx at first signs to prevent pneumonia Pulmonary edema PE Pneumothorax Arrhythmia Exposure Non-compliance
Varenicline mechanism, use
(Chantix)
Nicotine partial receptor agonist
Eases craving, withdrawal
Greatest smoking cessation success
Stop smoking methods
Nicotine replacement therapy (Patch, gum, lozenge, inhaler, nasal spray)
Buproprion
Varenicline
Buproprion mechanism
NE, dopamine reuptake inhibitor for nicotine cessation
Common newborn skin findings
Most infants are well, resolve quickly with these:
Gelatinous skin, esp. if pre-term
Seborrhea (“Cradle cap”)
Transient neonatal pustular melanosis
Sucking blister/Mongolian spot = hyperpigmentation may result
Acropustulosis of infancy
Milia - keratin cysts that resolve
Cutis marmorata
Erythema toxicum
Neonatal acne
Port-Wine-Stain = may have underlying neuro issues
Common newborn head findings
Cephalohematoma - subperiosteal, may calcify
Caput secundum - superficial edema
Intracranial hemorrhages - ultrasound through fontanelles
Common newborn eye findings
Congenital glaucoma = up IOP, abnormal angle between cornea and iris
Nasolacrimal duct obstruction/stenosis = pus near eye
“Leukocoria” = retinoblastoma, congenital cataract
Common newborn ENT findings
Low-set ears (top 1/3 should be level w/ eye) = genetic disorders
Choanal atresia if non-patent nares
Cleft lip or palate - may have bifid uvula
Epstein’s pearls = benign cysts on palate
Common newborn chest findings
Clavicles - broken from delivery
Chest asymmetry, or pectus abnormalities
RR 30-60, may be periodic from under-developed respiratory centers
Distress = Tachypnea, nasal flaring, acc mm use, grunting, cyanosis, GROUND GLASS appearance on CXR (pre-terms w/ low surfactant)
Common newborn abdominal findings
Palpable liver normal
Hydronephrosis most common abdominal mass
Umbilical hernia - diastasis recti - usually resolve before 1y
Common newborn extremity findings
Check for hip dysplasia:
Barlow = downward pressure on hips
Ortoloni = abduct hips
Checking for clicks, lumps
Common newborn GU findings
Ambiguous genitalia - check renal system by ultrasound
Hypospadias
Common newborn back findings
Hair tuft or sacral dimple = may indicate occult spina bifida
Common newborn neuro findings
Moro reflex = extend extremities when fall simulated
Plantar and palmar grasp
Rooting response = turn cheek towards stimulus
Suck reflex
Stepping response
Will have (+) Babinski and some clonus initially
Asymmetric tonic neck reflex = “Archer pose”
Trisomy 21 (Down’s) newborn findings
Upslanted palpebral fissures
Flat nasal bridge
Protruding tongue
Low-set ears
Brushfield spots on iris (bright, around border)
Simian crease (1 transverse crease on hand)
Large sandal gap between toes 1-2
Thick nuccal fold
Hypotonia (check by raising kid by arms, head won’t follow)
Trisomy 13 (Patau) findings and survival
6m survival
Cleft lip, clenched hand, overlapping fingers, polydactyl, clubfoot, heart defects
Trisomy 18 (Edwards) findings and survival
Survival to school age
Prominent occiput, low-set ears, clenched hand, rocker bottom feet, severe heart defects
Breastfeeding guidelines
Exclusively breastfeed for 6m, then add solid foods
Few CIs: HIV, HTLV-1, TB, alcohol/drugs, active VZV or HSV in mother; Galactosemia in infant
Birth weight should be regained by 10d
Stool progression
Meconium initially
Greenish w/ some residual meconium for first wk
Yellow curdish stool w/ regular breastfeeding
Newborn jaundice causes, complications
Related to breakdown of fetal RBCs - should clear in a few days
Neuro dysfunction induced when over 25-30mg/dL - more common w/ liver diseases:
Acute bilirubin encephalopathy and Kernicterus (permanent sequellae)
Emergent if jaundiced in first 24h
Things to check w/ ‘Well Child’ checks
Height, weight, head circumference, BMI
Signs of child abuse
Magical injuries
History doesn’t explain injury or time course
Treatment delay
DDx for milestone losses
Inborn metabolism error
Brain tumor
Neurodegenerative disorder
Craniosynostosis
Premature fissure closure = abnormal pathologic skull shape
Developmental milestones
3m = Raise head and chest when on stomach, Social smile 6m = Sit unassisted 7m = Respond to name, no 9m = Pincer grasp 12m = Walking on toes
“Fifth disease”
Erythema infectiosum from human parvovirus B19
Varicella incubation, progression, appearance
14d incubation
New vesicles for 4d
“Dew drop on a rose”
Rubeola common name, incubation, prodrome symptoms, sign, complications
Measles
10-14d incubation
Prodrome of 3Cs = Cough, Coryza, Conjunctivitis
Koplik’s spots on buccal mucosa 2d before rash over face spreading to trunk and extremities
Complications: Respiratory infections, encephalitis
Rubella common name, time course, symptoms, sign, complications
German measles
3d course
Pinpoint rash starts on face, progresses over trunk, extremities
Forchheimer spots = palatal petechiae
Complications: Acute encephalitis, thyroiditis
Most dangerous as congenital syndrome (Purpuric rash, hearing loss, mental retardation, CV and ocular defects)
Erythema infectiosum cause, incubation, progression, complications
Due to parvovirus B19
Incubation 7-14d
Slapped cheeks -> Fishnet erythema -> Rash recurrence after resolution
Non-blanching rash
Complications: Arthropathy, birth defects, aplastic crisis in those w/ hemolytic disorders or IC’d patients
Roseola infantum cause, incubation, course
HHV-6,7
Incubation 5-15d
High fever for 3-4d, but child feels fine -> Macular rash appears as fever disappears
Hand-Foot-Mouth disease
Coxsackie virus A16 or Enterovirus A71
Incubation 3-6d
Sore lesions (chancre-like) in mouth and on tongue, some on hands and feet
Lasts 7-10d
Coxsackie (A esp, sometimes B) viruses cause what?
Herpangina:
Young children
Prodrome: Sore throat, fever
Painful ulcer lesions on tonsils/uvula/palate
Classic childhood exanthems and causes?
I = Measles (Rubeola) II = Scarlet Fever (GABHS) III = Rubella (German measles, togavirus) IV = Filatow-Dukes disease (Obsolete) V = Erythema Infectiosum (Parvovirus B19) VI = Roseola Infantum (HHV-6,7)
Asthma risk factors
Genetics, Male, Hyperresponsive airway, Atopy
Allergen and irritant exposure (dust, smoke), Respiratory infxns
Asthma pathology
Airway inflammation and Bronchial smooth muscle hyperreactivity
Cholinergic system role in asthma
ACh binds M3 receptors on airway smooth muscle -> Bronchoconstriction
M2 autoreceptors on presynaptic cholinergic neurons limit ACh release when ACh binds
Atopy usually manifests w/ what responses?
Allergic rhinitis, Asthma, Hay fever, Eczema
Rescue treatment for asthma when no other is available?
Activate SNS somehow to cause Epi release, e.g. get in a car wreck
“But this is hard to titrate”
Asthma symptoms
Coughing, Wheezing, Shortness of breath, Chest tightness
Asthma signs
Wheezing, Thoracic hyperexpansion, Nasal secretions/polyps, Atopy signs
Asthma spirometry
Obstructive defect reversible w/ a bronchodilator
FEV1/FVC ratio low, then normal w/ bronchodilator
Asthma treatments (3 classes) Avoid doing what?
Long-term control = Inhaled corticosteroids to limit inflammation (Acute oral dose may help contain additional symptoms)
b2-agonists:
Generally short-acting for rescue = Albuterol/Levalbuterol
Some are long-acting for most of 1d = Salmeterol/Fometerol, used w/ steroids
DON’T USE LONG-ACTING b2-AGONISTS ALONE -> develop tolerance, limits effectiveness of rescue inhaler. Use w/ inhaled corticosteroids
Leukotriene receptor antagonists (Montelukast, Zafirlukast) limit inflammation and secretions. Good for allergies too.
Status asthmaticus, signs, treatments
Asthma attack unresponsive to b2-agonists = Need urgent evaluation
Silent chest = No air movement = Bad news
Treat w/ upright position, O2, Albuterol x3, IM steroid injection, Ipratroprium nebulizer (anti-ACh), Subcu Epi, IV Terbutaline (b-agonist
May need to intubate for mechanical ventilation, induce w/ KETAMINE (bronchodilatory properties)
Causes of wheezing
Asthma Pulmonary edema Allergy Pneumonia Foreign body aspiration
Gold standard for diagnosing pneumonia
CXR
But may be negative - still suspect pneumonia if convincing H&P
Pneumonia causes
Immunodeficiency (i.e. HIV)
TB
Community-acquired pneumonia, Ventilator-AP, Hospital-AP, HealthCare-AP
Pneumonia: CURB-65
Confusion, Uremic, Respiratory rate over 30, BP below 90/60, Age over 65
If at least 2 of these -> Patient should stay in hospital
Consider ICU admission if at least 3 and bad vitals
Considerations for pneumonia treatment
Antibiotics should always cover Strep pnumonia if cause is not specifically identified
Should also consider covering CA-MRSA
Usually need to empirically treat within 4h
Best marker for determining sepsis treatment
Procalcitonin (PCT) - Guides both when to start and stop antibiotics for inpatients w/ sepsis due to pneumonia
0.5mcg/L is the level recommended for starting (over) and stopping (under)
Pneumonia associations
Bronchiogenic carcinoma patients may initially present w/ pneumonia
When to followup w/ pneumonia patients
CXR 4-6w later for all patients over 40 and those who do or have smoked
Complications of overdiagnosis and overtreatment of pneumonia
What to do instead?
Unnecessary C. diff colitis
Make sure to use appropriate antibiotics strongly and early, then de-escalate when possible
Pneumonia treatments
If no disease in last 3m: Macrolide/Doxy
If some complicating disease, infxn, or factor: Respiratory quinolone OR b-lactam + Macrolide/Doxy
If inpatient: Respiratory quinolone OR Ceftriaxone + Azithro/Doxy
If ICU: Ceftriaxone (Aztreonam if allergic) + IV Azithro/Respiratory quinolone - NEVER MONOTHERAPY IN ICU
Pneumonia prevention
Smoking cessation
Influenza vaccine - live for 2-49y, inactive for IC’d and healthcare workers
Pneumococcal vaccine - 13- and 23-valent for elderly and IC’d
Common signs, associations w/ different types of lung cancer
Smoking
Chronic non-productive cough w/ occasional hemoptysis
Mass (over 3cm)/nodule on imaging
Wheezing, Stridor, Dyspnea, Hoarseness
Neurologic
Nail clubbing
SVC syndrome from R lung mass - Upper edema
Metabolic - Cushing’s syndrome in small cell or bronchial carcinoid
SIADH in small cell
Hypercalcemia, hyperinsulinemia w/ squamous cell type
Gynecomastia w/ large cell carcinoma
Small cell carcinoma appearance, sites, treatment
Lympocyte-like carcinoma = round, oval nuclei
Combined cell type often (small cell plus adeno-, squamous, or large cell types)
Most are proximal lesions
Often already metastasized once detected
Neurosecretory granules
Chemo and radiation
Surgery not possible
Lung cancer causes
Smoking - nicotine not carcinogenic, but lots of carcinogens in smoke - Number, duration, age of initiation, depth of inhalation, tar/nicotine levels in cigarettes
Similar alterations caused from smoking other drugs
Atmospheric pollutants:
Nickel, Chromium, Arsenic compounds
Benzpyrene, Chloromethyl ether (esp. small cell)
Radioactive material, e.g. Radon (small cell)
Asbestos
Mustard gas
Iron/silica exposure
Genetic: Loss of short arms of chr3 or chr11
Common types of lung cancer
Non-small cell: Squamous cell carcinoma (20%) Adenocarcinoma (38%), including: Bronchoalveolar carcinoma (3-4%) - presents as pneumonia that doesn't resolve Large-cell carcinoma (5%)
Small-cell (13%) Carcinoid tumor (1-4%)
Why does cancer kill patients?
Cancer cells invade and compromise vital structures
OR Cancer makes patient hypercoagulable -> Throw thromboemboli -> Death from large PE
Adenocarcinoma origin, causes, metastasis
Probably arises from mucin-secreting cells in peripheral bronchi
Caused by exogenous carcinogens, interstitial fibrosis, scleroderma
Often metastasizes to liver, adrenal (include in chest CTs), bone, brain
Squamous cell carcinoma origin, appearance
Usually from large bronchi mucosa = proximal, hilar lesions
Mucosal lining most susceptible
Hyperplasia of mucin-secreting columnar epithelial cells -> Replacement w/ metaplastic stratified squamous epithelium
Large cell carcinoma cell appearance, site and appearance, treatment
Undifferentiated
Usually limited to periphery, similar to adenocarcinoma
Usually large, peripheral, can be treated surgically
Carcinoid tumor name, site, markers, symptoms, imaging, treatment
Bronchial adenoma
Submucosal gland lesions in bronchial wall
Rapid growth and invasion of surrounding structures - highly vascular
Neuroendocrine markers, dense core granules
Symptoms of hemoptysis, pulmonary infections, dyspnea
CXR shows pneumonia, hilar mass, or a rare peripheral nodule
DO NOT BIOPSY due to hemorrhage risk, just remove it
Hamartoma appearance, cells, treatment
Benign tumor of disorganized normal lung elements
No capsule, but lesion is round and sharply defined
Biopsy to eliminate malignant cancers from DDx
“Shells out”
Usually remove if peripheral
TNM lung cancer staging, important demarcations
What is surgically resectable?
Define wrt local extent of the Tumor, regional lymph Nodes, and distant Metastasis
T2 - Larger than 3cm, but at least 2cm from carina
T3 - Larger than 7cm, within 2cm of carina
N2 - Ipsilateral mediastinal and/or subcarinal LN involvement
M1 - Distant metastasis present (Always Stage IV)
Stage IIIA and earlier often surgically resectable (T3, N2, M0)
Pancoast syndrome cause, symptoms
Neoplasm in lung apex
Shoulder, arm pain, weakness
Hoarseness
Horner’s syndrome (Miosis, Ptosis, Anhydrosis)
Skin manifestations of lung cancer, association
Acanthosis nigricans - brownish hyperpigmentation
Common w/ bronchial adenocarcinoma
Vascular manifestations of lung cancer
Thrombophlebitis, Recurrent or migratory arthritis, PE, Non-bacterial endocarditis
Lung cancer diagnostic tests
Cytology of sputum for centrally located tumors
CXR, CT
PET
Bronchoscopic biopsy
Lung cancer treatments
Radiation therapy Radiofrequency ablation Surgery for Stages I and II (Adjuvant chemo/rad w/ S2) Chemotherapy/Radiation for S3 Chemo or targeted therapy for S4
Mesothelioma cause, presentation, gross appearance
Asbestos exposure
Dyspnea, chest pain
Neoplastic growth surrounds and encases lung, invades neighboring pleura, pericardium
TB growth rate, affect on treatment, antibiotics, contagiousness
One division per 20h = hard to kill since most antibiotics target more rapidly dividing organisms, cultures take 3-6w
Streptomycin = first treatment, targets ribosomes
Isoniazid = targets cell wall, ups host NO
Close contact and active disease usually needed for transmission, antibiotics make hosts noninfectious
TB risk factors
Host: Substance abuse, malnutrition, cancer, DM, gastric bypass surgery, HIV, steroid use, TNF inhibitors
Environmental: Household contacts, born in an endemic area, low socioeconomic class = crowded community w/ poor sanitation
When people present w/ TB
Infants, adolescents, elderly, HIV
TB infection signs
Initial: Fever lasting weeks Pleuritic chest pain, substernal pain from enlarged LNs CXR signs occasionally POSITIVE PPD
Reactivation and disseminated disease occurs rarely in those who aren’t IC’d:
Fever, night sweats, weight loss, fatigue
Sepsis, meningitis, pericarditis, skeletal disease, UTI
Cough, dyspnea, hemoptysis, pneumothorax
May have pulmonary crackles, clubbing
TB labs
Often normal early
High CRP
CXR w/ bilateral upper lobe infiltrates, cavities, but may be normal
CT more sensitive
PPD test
Inject TB protein subcutaneously
If positive -> Large diameter of indurated skin at site
False positives w/ previous vaccination, other mycobacterial infection
False negatives w/ advanced HIV, IC’d, or active infxn (no CD4 response yet)
Active TB diagnostic test
Acid-fast stain or fluorescent stain
Latent TB treatment
Prevent reactivation and spread, especially in those who might expose many others
Isoniazid for 9m, add vitamin B6 for preventing neuropathy, scan liver enzymes for hepatitis signs
Alt: Rifampin 4m, but not as effective
Active TB treatment
All get 4Rx combo until cultures and sensitivities are determined: Isoniazid, Rifampin, Pyrazinamide, Ethambutol for 2m, tailor therapy after 2m
Once sputum smears are negative, treat another 4m with Isoniazid and Rifampin
Fluoroquinolones may also be used
TB vaccine
BCG vaccine - based on attenuated M. bovis
Common, but old and needs updating
Interstitial lung disease causes, affected tissues
How to identify?
Most often idiopathic - lots of tissues may be affected
Exposures - chicken coops, silica, smoking
Disease of interstitium: fibrous septae (most commonly affected tissue = interstitial pulmonary fibrosis), alveolar walls, lymphatics, capillaries
H&P: Exposure history, Velcro rales, dry cough
Use CT scans
Pulmonary fibrosis association, findings, pathophysiology, presentation timing
Associated w/ smoking
Bibasilar inspiratory crackles, Clubbing, Dyspnea, Cough, Restrictive pathology (Low Total Lung Capacity)
Symptoms start about 6m before clinical presentation
Monitoring ILD progression monitoring, treatment
Pulmonary function tests
6min stress tests
O2 requirement
No response to steroids, smoking cessation
Periods of rapid clinical deterioration will occur
Clinical trials: Pirfenidone, Nintedanib
Causes of granulomatous lung diseases
Infections (TB) Sarcoidosis Hypersensitivity pneumoitis Wegener's granulomatous Reaction to tumors, foreign bodies
Key features of granulomas
Discrete
Avascular
Epithelioid histiocytes
Necrotic:
Caseous = TB
Abscess-like granuloma = Fungi
Degeneration/Fibrosis = Wegener’s, necrotising sarcoid, Churg Strauss, Rheumatoid nodule
Non-necrotic:
W/o interstitial inflammation: Sarcoid
W/ interstitial inflammation: Hypersensitivity pneumonitis
Radiologic appearance of sarcoidosis
I: Bihilar lymphadenopathy
II: Pulmonary infiltrate w/ BHL
III: PI w/o BHL
IV: Honeycombing
Sarcoid treatments
I: None
II-IV: Steroids usually
Histiocytosis X mechanism, histo, pathology, findings, treatment
Mononuclear phagocyte system disorder = accumulation X bodies in cytoplasm Small cysts Mixed obstructive/restrictive pathology Quit smoking
Eosinophilic granuloma history
Mononuclear phagocyte system disorder = accumulation
20-40yo smoker
Non-productive cough, dyspnea, pleurisy
Wegener’s granulomatosis triad, test and physical findings, CT, treatment, course
Necrotising granulomas in URT, LRT later + Glomerulonephritis + Generalized necrotising vasculitis c-ANCA positive Cavitated pulmonary nodules in any zone Saddle nose High-dose corticosteroids Frequent relapses
Hypersensitivity pneumonitis cause, prognosis
Due to exposure = Remove exposure
Poor prognosis w/ chronic exposure
Lymphangioleiomyomatosis demographic, symptoms, associations, CT
Pre-menopausal women
Dyspnea, pneumothorax, cough, pleurisy, hemoptysis
Associated w/ renal angiomyolipomas and tuberous sclerosis
Multiple thin-walled cysts w/ even lung distribution
How to evaluate ILD
Extensive history of age, gender, comorbidities, smoking, occupation, hobbies, pets, FH, duration of symptoms
Physical exam, labs, imaging, PFT
What two diseases don’t happen in smokers?
Sarcoidosis
Ulcerative colitis
PE findings w/ ILDs
Inspiratory crackles
Cardiac murmur, edema
Clubbing
Rash, arthritis, skin changes
Use of bronchoscopy in ILDs
Rule out infxn - Don’t give immunosuppressants if the patient has one!
Causes of interstitial shadowing on CXR
Lung parenchymal disease
Cardiogenic pulmonary edema (Cardiac hypertrophy, or if MI)
Compare to old scans to make sure
When to refer IPF patients for lung transplant
IPF patients = progressive, irreversible disease -> Refer early (worst survival while waiting)
COPD patients = Not as progressive, must maximize therapy and limit risk factors before referral
CF = early for bilateral replacement
Age limits = must be younger than 65yo
Typical volume of pleural fluid
5-25mL
Physiological causes of pleural effusion (3)
Increased drainage of fluid into pleural space
Increased production of fluid by cells in the pleural space
Decreased lymph drainage of fluid from the pleural space
Diseases causing pleural effusion, mechanism
CHF = Up pulm capillary pressure = Transudate Pneumonia = Up pulm capillary permeability = Exudate Atelectasis = Up intrapleural pressure Hypoalbuminemia = Down oncotic pressure = Transudate Malignancy = Down pleural membrane permeability or Lymph blockage = Exudate
Pleural effusion physical findings
Dyspnea, pleurisy, cough
Dullness to percussion, decreased tactile fremitus, asymmetric chest expansion, decreased breath sounds, egophony
Tests for pleural effusion, what to watch for?
CXR, US, CT, pleurocentesis
Does shadow move w/ changes in position (upright vs. supine vs. decubitus)
How to differentiate between total atelectasis and massive pleural effusion?
Are heart/mediastinum shifted away from (effusion) or towards (atelectasis) pathology?
Thoracentesis indications, complications
Pleural effusion w/ unknown etiology
Therapeutic for symptomatic relief
Air-fluid level in pleural space
Concern for empyema, parapneumonic effusion, hemothorax, malignancy
Determine if transudate/exudate
Pneumothorax, re-expansion of pulmonary edema, malignant seeding
DON’T PERFORM if elevated INR to avoid bleeding
Where to perform thoracentesis
Upper border of lower rib
Diseases w/ Low glucose and low pH in pleural fluid
RA, malignancy, empyema, esophageal rupture, TB
Causes of chylothorax vs pseudochylothorax
Appearance?
Chylo = Trauma, malignancy (acute, normal pleural surface, normal cholesterol)
Pseudo = Chronic effusion, usually TB or RA (fibrous pleura, high cholesterol)
Both are milky in appearance
Chest tube indications
Empyema, hemothorax, parapneumonic effusion, malignant effusion
Transudate vs. Exudate classification
Transudate if ALL THREE of these are true:
Pleural fluid protein : serum protein ratio 0.5 at most
Pleural fluid LDH : serum LDH ratio 0.6 at most
Pleural fluid LDH below 2/3 of serum LDH or 200 at most
RDS CXR appearance
Diffuse ground glass appearance through whole lung fields
Cause of RDS
Surfactant deficiency, usually in preterm babies -> Poor compliance, atelectasis, increased breathing work, hypoxia
RDS risks
Fetal hyper insulinism/IDM impedes production
Males, whites worse
Multiple gestation
When does surfactant start appearing?
When Type II alveolar cells are present at 20w
No viable lung tissue before this time
Surfactant makeup, manufacture
90% lipid, 8% protein
Phosphatidylcholine - hydrophilic head, two hydrophobic tails, saturated and unsaturated
SP-A,B,C,D
Made in T2 alveolar cells SER, stored in lamellar bodies, exocytosed, converted to tubular myelin
Much is recycled
Surfactant proteins
B - most important, for surface tension reduction
A - for regulating secretion
D - for viral defense
C
Compounds inhibiting surfactant production
Meconium
Amniotic fluid
Blood-related compounds
Laplace’s Law
P = 2T/r
Greater radii = Less pressure needed to keep distended
Why was RDS called hyaline membrane disease?
Alveoli overdistend -> Epithelial damage -> Proteins leak into airspace, further impairing surfactant function = Thick hyaline membrane lining alveoli on histology
RDS clinical diagnosis
Premature infant w/ central cyanosis due to R->L shunt (PDA) and pulmonary edema, tachypnea, labored breathing, fine rales on auscultation
RDS treatment
Intratracheal surfactant admin
Assisted ventilation
RDS prognosis
Related to gestational age and birth weight
May develop bronchospastic disease due to ventilation trauma
Chronic lung disease may develop
Cystic fibrosis genetics, pathophys, survival, evolutionary benefit
Autosomal recessive mutation to CFTR on chromosome 7 - over 1900 mutations identified, dF508 phenylalanine deletion most common
Cystic Fibrosis Transmembrane conductance Regulator = cAMP-activated Cl- channel; mutations cause defects of CFTR limiting Cl- flow in EXOCRINE epithelial cells -> Dry thick secretions obstructing ducts due to stasis, pH imbalance -> Inflammation w/ impaired PMNs -> Infection, especially w/ Pseudomonas
Median survival ~41y now
Provides protection against cholera toxin as carrier
CF pathophys of sweat glands, sinuses, salivary glands, lungs, pancreas, GI, liver, GU
Poor salt reabsorption -> Elevated NaCl in sweat
Hypertrophy of exocrine cells -> Chronic pansinusitis and POLYPS
Plugging and dilation of gland ducts
Sequential obstruction: Mucus plugging -> Infection -> Bronchiolitis -> Bronchitis -> > Bronchiectasis -> Cor pulmonale, hemoptysis, pneumothorax -> Respiratory failure
Atrophic pancreas from no Cl- movement to activate cells -> w/ steatorrhea and malnutrition OR pancreatitis
Increased mucus secretion, fat-laden feces -> Obstruction: Meconium ileus (pathognomonic), intussusception
Cholelithiasis or atrophic gallbladder, eventual cirrhosis
Viscous cervical mucus -> Endocervicitis, amenorrhea
Epididymis obstruction, immotile sperm
CF findings
Poor growth, delayed maturation, decreased muscle mass, fat-soluble vitamin deficiencies
Polyps, inflamed mucus membranes, rhinorrhea
Increased chest diameter, wheezes, crackles, hyperresonance
Fatty stools
CF diagnostic tests
Newborn screen for immunoreactive trypsin (IRT)
SWEAT TEST for high Cl- content on at least 2 occasions
pHTN symptoms, definition, associations
Shortness of breath
Pressure over 25mmHg at rest
Associated with scleroderma, congenital sys->pulm shunts, portal hypertension, HIV; L-sided CHF; COPD, interstitial lung disease; PE
Genetic pHTN causes
Bone morphogenetic protein receptor tII (BMPR2) and activin receptor-like kinase 1 (ALK1) mutations
pHTN findings
Increased P2, Murmur, Edema
pHTN tests
V/Q scanning, CXR
