Pulmonary Flashcards
lung function
conducting zone:
trachea, primary bronchus and terminal conducting bronchioles; warms air, traps foreign matter
respiratory zone:
terminal respiratory bronchioles and alveoli
alveoli:
gas exchange
diffusion capacity based on: surface area, thin diffusing area, partial pressure and concentration of gases
low V:Q ratio
V = VENTILATION
Q = PERFUSION
LOW VENTILATION WITH INCREASED OR NORMAL PERFUSION
-low ventilation impairs gas exchange –> dec arterial partial pressure of oxygen and decreased excretion of CO2 –> stim respiratory, increased ventilation to increase ratio towards 1
Physiologic Low V:Q Ratio
-found at base of lungs, due to gravity - receive BOTH greater perfusion and more ventilation (perfuse > vent)
Pathologic Low V:Q Ratio
- ASTHMA, CHRONIC BRONCHITIS, AND ACUTE PULM EDEMA
- HYPOXEMIC RESPONSE TO DEC PaO2 IS LOCAL HYPOXIC VASOCONSTRICTION –> PULM HTN
- right ventricle has to pump against higher pressures –> over time, RIGHT HEART FAILURE (COR PULMONALE)
high V:Q ratio
AREA OF DECREASED PERFUSION COMPARED TO VENTILATION
Physiologic High V:Q Ratio
- at apices of lungs
- reactivation of TB tends to occur here - due to the relatively higher O2 content of lung tissue in apices
Pathologic High V:Q Ratio
- EMPHYSEMA, PULM EMBOLISM OR FOREIGN BODY
- good ventilation but bc decreased blood flow, fails to oxygenate blood
- areas of no perfusion and normal vent = “dead space”
mechanics of breathing
- during quiet breathing, inspiration accounts for most of the work; expiration a passive process
- 90% OF NORMAL WORK OF BREATHING IS DUE TO CONTRACTION OF THE DIAPHRAGM
control of respiration
VENTILATION IS STRICTLY REGULATED PRIMARILY BY CHANGES IN PaCO2
Controlled by:
- CENTRAL CHEMORECEPTROS IN THE MEDULLA - indirectly respond to changes in serum pH via PaCO2 in CSF –> medulla stimulates phrenic nerve –> inc rate/depth of breathing
- PERIPHERAL CHEMORECEPTORS IN CAROTID BODIES AND AORTIC BODIES - respond directly to inc PaCO2 in arterial blood –> stim neurons affecting the medulla –> inc rate and depth of breathing (to lower PaCO2) - sensitive to dec arterial PaO2 but only if significant decline <60
-DKA STIMULATES RESPIRATORY CENTERS, CAUSING KUSSMAUL’S RESPIRATIONS
lung defenses
alveolar cells:
- type I: make up supporting tissue
- type II: PRODUCE SURFACTANT
mucociliary escalator:
-covers nose, bronchi and most of bronchioles
alveolar macrophages
-some evade them: encapsulated organisms, pseudomonas, mycolic acid layer of m.tuberculosis
mast cells
-initiate inflam, repair lung and immunity
pmns
-temporarily present during lung infx; seen in smokers
lung volumes
tidal volume TV - air moved in and out during quiet breathing
residual volume RV- vol of air remains after max expiration
expiratory reserve ERV - vol that can be further exhaled after normal expiration
inspiratory reserve IRV - vol that can be further inhaled after normal inspiration
vital capacity - max vol that can be exhaled after max inhalation IRV + TV + ERV
total lung capacity TLC - vol of lungs at max inspiration
functional residual capacity FRC - vol of gas in lungs at normal tidal volume end-expiration (ERV + RV)
FEV1 (forced expiratory vol in 1 sec) - vol exhaled at end of first second of forced expiration
FVC (forced vital capacity) - vol of air that can be expelled from a max inflated lung with the patient breathing as hard and fast as possible
atypical breath sounds
WHEEZING - high-pitched, whistling, continuous, usually louder during expiration, produced by narrow/obstructed airways - COPD, ASTHMA, bronchiectasis, bronchiolitis, lung ca, sleep apnea, chf, gerd, anaphylaxis, foreign body
RHONCHI - rumbling/rattling, coarse, low pitched sounds, like snoring that may clear w/ cough - INC SECRETIONS
CRACKLES/RALES - non-continuous, heard during inspiration, due to popping open of collapsed alveoli and small airways (from fluid, exudates) - pnm, atelectasis, bronchitis, bronchiectasis, pulmonary edema and fibrosis
STRIDOR - monophonic sound usually loudest over anterior neck due to narrowing of larynx or anywhere over trachea
asthma
- MC CHRONIC CHILDHOOD DZ
- RF: ATOPY
SAMTER’S TRIAD: ASTHMA, NASAL POLYPS, ASA/NSAID ALLERGY
Pathophys:
AIRWAY HYPERREACTIVITY
-extrinsic (allergic) - triggers pollen, dander, dust, mold, etc, MC CHILD/ADOLESCENTS, ASSOC W/ IgE
-intrinsic - triggers infx, pharmacologic (b-blockers, asa, nsaids, acei), occupational, exercise, emo, cold air
BRONCHOCONTSTRICTION
- airway narrowing 2ry to smooth muscle constriction, bronchial wall edema, thick mucus secretion, collagen deposition, air trapping
- OBSTRUX - dec expiratory flow, inc resistance, v/q mismatch
INFLAMMATION
-2ry to cellular infiltration (t-lymphs, neutrophils, eosinophils and cytokines), inc histamine release from mast cells
- sx:
- DYSPNEA, WHEEZING, COUGH (esp at night), chest tight, fatigue
- PROLONGED EXPIRATION W/ WHEEZING, HYPERRESONANCE, dec breath sounds, tachy/tachy, use accessory muscles
- SEVERE - unable to speak full sentences, ams, pulsus paradoxus, cyanosis, tripod, silent chest
- dx:
- PFTs GOLD STANDARD = REVERSIBLE OBSTX
- BRONCHOPROVOCATION - methacholine challenge test, bronchodilator challenge test, exercise challenge test (if PFTs are nondiagnostic)
- PEAK EXPIRATORY FLOW RATE - best and most objective way to assess asthma exacerbation severity and pt response in ED; PEFR >15% from initial attempt = response to tx, normal 400-600
- Pulse Ox - <90% indicative of respiratory distress
- ABG, CXR
- Admission Criteria: PEFR <50% of predicted, ER visit w/in 3 days of exacerbation, status asthmaticus, posttreatment failure, AMS
- Discharge Criteria: PEFR >70% of predicted, >15% since intial, subjective improvement, clear lungs w/ good air movement, adequate fu w/in 24-72 hrs, response sustained for 1 hour post-tx
management of asthma
ACUTE Exacerbations:
B2 AGONISTS SHORT-ACTING (SABA)
- 1ST LINE TX FOR ACUTE
- ALBUTEROL, TERVUTALINE, EPINEPHRINE via NEB
- bronchodilator, dec bronchospasm
ANTICHOLINERGICS (ANTIMUSCARINICS)
- IPRATROPIUM
- bronchodilator
CORTICOSTEROIDS
-anti-inflam, all but mildest should be dc’d on short course oral cortico; dec relapse
LONG-TERM Maintenance:
INHALED CORTICOSTEROIDS
- DRUG OF CHOICE FOR LONG-TERM MAINTENANCE
- BECLOMETHASONE, FLUNISOLIDE, TRIAMCINOLONE
- cytokine and inflam inhibition
LONG-ACTING B2 AGONISTS (LABA)
- SALMEROL, FORMOTEROL
- bronchodilator, prevents sx
MAST CELL MODIFIERS
- CHROMOLYN, NEDOCROMIL
- inhibits mast cell and leukotrien-mediated degranulation; inhibits acute phase response to cold air, exercise, etc
LEUKOTRIENE MODIFIERS/RECEPTOR ANTAGONISTS
- MONTELUKAST, ZAFIRLUKAST, ZILEUTON
- blocks leukotriene-mediated neutrophil migration, smooth muscle contraction
THEOPHYLLINE
- methylxanthine, a bronchodilator that improves respiratory muscle endurance
- higher dose needed for smokers
- narrow therapeutic index - arrhythmias, seizures
OMALIZUMAB
-anti-IgE antibody - used in severe, uncontrolled
asthma classification
Intermittent - SABA prn sx: 0-2x /day 0-2x/week SABA use: 0-2x /day 0-2x/week nighttime awakening: <2x/month interference w/ activity: none exacerbations req steroids: 0-1/yr
Mild Persistent - SABA prn + LOW-DOSE ICS sx: >2 days/week SABA use: >2 days/week nighttime awakening: 3-4x/month interference w/ activity: minor exacerbations req steroids: 2+/yr
Moderate Persistent - SABA prn + MED-DOSE ICS OR LOW ICS + LABA, add LTRA sx: daily SABA use: daily nighttime awakening: >1x/week interference w/ activity: some exacerbations req steroids: 2+/yr
Severe Persistent - HIGH-DOSE ICS + LABA, +/-OMALIZUMAB
sx: throughout day
SABA use: several times/day
nighttime awakening: often, usually nightly
interference w/ activity: extreme
exacerbations req steroids: 2+/yr
*step-wise –> step down if sx controlled for 3+ months
COPD
Irreversible airflow obstx due to: LOSS OF ELASTIC RECOIL, INCREASED AIRWAY RESISTANCE
- chronic bronchitis usually episodic, emphysema steady decline
- RF: SMOKING, a-1 ANTITRYPSIN DEFICIENCY (only genetic dz linked - younger pt <40y, panlobar emphysema)
EMPHYSEMA
- abnormal, permanent enlargement of terminal airspaces
- smoking –> chronic inflam –> loss of elastic recoil and inc compliance –> airway obstruction
CHRONIC BRONCHITIS
- PRODUCTIVE COUGH 3+ MONTHS X 2 CONSECUTIVE YEARS
- chronic inflam –> hypersecretino of mucus, airway narrows, inc resistance –> airway obstx
- mucus plugging and mucociliary escalator destruction makes pt more prone to infx
-sx:
EMPHYSEMA
-DYSPNEA MC
-HYPERINFLATION: hyperresonance, dec breath sounds, dec fremitus, barrel chest, pursed-lip breathing
-respiratory alkalosis, matched v/q defects, mild hypoxemia, cachectic, “PINK PUFFERS”
BRONCHITIS
- PRODUCTIVE COUGH HALLMARK
- RALES, RHONCHI, WHEEZING, signs of cor pulmonale (peripheral edema, cyanosis)
- respiratory acidosis, inc hgb/hct
- severe v/q mismatch, HYPOXEMIA, HYPERCAPNIA
- obese and cyanotic “BLUE BLOATERS”
- dx:
- PFTs/SPIROMETRY - GOLD STD
- CT/CXR
- ECG
management of COPD
BRONCHODILATORS
-COMBO w/ anticholinergics + B2 agonists better
- Anticholinergics: IPRATROPIUM, TIOTROPIUM (preferred over B2 agonists w/ copd)
- B2 Agonists: ALBUTEROL, TERBUTALINE, SALMETEROL
- Theophylline - only used in refractory cases (narrow therapeutic index, monitor levels –> arrhythmias and seizures)
CORTICOSTEROIDS
-may be added to long-acting bronchodilators
OXYGEN
-only med tx proven to dec mortality (dec pulmonary htn and cor pulmonale)
Prevent Exacerbations
- smoking cessation
- vaccinations
- pulmonary rehab
- surgery (lung reduction, transplant)
- abx if increased sputum, change in quality or cxr evidence of infx
- AZITHRO has been shown to have anti-inflam properties in lung
GOLD Criteria - COPD staging
all –> FEV1/FVC <70%
I: Mild
PFT% predicted: FEV1 80+%
Tx: Bronchodilators (short-acting), dec rf
II: Moderate
PFT% predicted: FEV1 50-79%
Tx: Bronchodilators (short-acting) + LONG-ACTING
III: Severe
PFT% predicted: FEV1 30-50%
Tx: Bronchodilators (short-acting) + long-acting + REHAB, steroids if inc exacerbations
IV: Very Severe
Cor pulmonale, respiratory failure, heart failure, FEV1 <30
Tx: Bronchodilators (short-acting) + long-acting + rehab, steroids if inc exacerbations, + O2 THERAPY
bronchiectasis
IRREVERSIBLE BROCNHIATL DILATION 2RY TO TRANSMURAL INFLAMMATION –> destruction of muscular and elastic tissues of bronchial wall, airways collapse easily -> OBSTX AND IMPAIRED CLEARANCE OF MUCUS –> LUNG INFX
Etiologies:
- Recurrent/chronic lung infx
- H.INFLUENZA MC IF NOT CYSTIC FIBROSIS
- PSEUDOMONAS MC IF CYSTIC FIBROSIS
- Hereditary - CF mc cause in US, a-1 antitrypsin deficiency
- Obstx - foreign body aspiration, tumors severe mucus
- sx:
- DAILY CHRONIC COUGH W/ THICK, MUCOPURULENT, FOUL-SMELLING SPUTUM, chest pain, often devo recurrent pneumonia
- HEMOPTYSIS (50-70%) due to erosion into bronchial arteries
- persistent crackles at base, dyspnea, wheeze, rhonchi
- dx:
- HIGH RES CT SCAN - STUDY OF CHOICE: airway dilation, lack of taperiong of bronchi, wall thickening, muco plugs
- PFTs: OBSTRUCTIVE PATTERN
- CXR
- Sputum cultures
- Bronchoscopy
- tx:
- ABX, mucus management (bronchodilators, anti-inflam, sx, embolization for bleed)
- sx in severe, complicated cases
- THICK BROWN SPUTUM –> ASPERGILLUS (ITRA + CORTICO)
- MYCOBACTERIUM AVIUM COMPLEX (MAC) –> CLARITHRO + ETHAMBUTOL
PFTs -obstructive vs restrictive
Obstructive
- INCREASED LUNG VOLUMES
- HYPERINFLATION: INC TLC
- OBSTRUCTION: DEC FEV1, DEC FVC, DEC FEV1/FVC
- inc compliance w/ emphysema
- ASTHMA, COPD, BRONCHIECTASIS, CF, COAL WORKERS PNEUMOCONIOSIS
Restrictive
- DECREASED LUNG VOLUMES
- DEC TLC, FVC
- NORMAL OR INC FEV1/FVC
- dec compliance
- SARCOID, PNEUMOCONIOSIS, IDIOPATHIC FIBROSIS, dec muscle effort: Myasthenia gravis, polio, scoliosis
cystic fibrosis
-defective CF transmembrane receptor (CFTR) –> prevents Cl transport (water mvmt out of cell) –> buildup of thick mucus in lungs, pancreas, liver, intestines –> obstx lung disease and exocrine gland dysfx
- sx:
- YOUNG, W/ BRONCHIECTASIS, PANCREATIC INSUFFICIENCY, GROWTH DELAYS AND INFERTILITY
- GI: MECONIUM ILEUS, PANCREATIC INSUFFICIENCY (dec fat absorption, steatorrhea, vit ADEK deficiency)
- Pulm: RECUR RESP INFX (esp staph and pseudo), chronic sinusitis
- Infertility 95%
- dx:
- ELEVATED SWEAT CHLORIDE TEST - PRIMARY, >60 mmol/L on 2 occasions after Pilocarpine
- CXR: BRONCHIECTASIS, HYPERINFLATION
- PFTs: OBSTRUCTIVE
- DNA definitive
- sputum cultures –> pseudomonas, h.influenzae
- tx:
- AIRWAY CLEARANCE - bronchodilators, mucolytics, abx
- PANCREATIC ENZYME REPLACE - supplement ADEK
- lung and pancreas transplant, vaccinations
sarcoidosis
NON-CASEATING GRANULOMAS, BILAT HILAR LYMPH
CLASSIC PRESENT: YOUNG PT W/ RESPIRATORY AND CONSTITUTIONAL SX, BLURRED VISION AND ERYTHEMA NODOSUM
- inc prevalence in AA, northern europe, female
- onset 20-40y
EXAGGERATED T-CELL RESPONSE to a variety of antigens or self-antigens –> CENTRAL IMMUNE ACTIVATION, PERIPHERAL IMMUNE DEACTIVATION, t-cell accumulation –> GRANULOMA FORMATION
-granulomas take up space, disrupt the normal stx/fx
- sx:
- 50% asymptomatic, most complications are w/ lungs
- Pulmonary 90% - DRY COUGH, DYSPNEA, CHEST PAIN
- Lymphadenopathy - painless, intrathoracic, HILAR NODES
- Skin 25% - ERYTHEMA NODOSUM, LUPUS PERNIO (violet, raised discoloration of nose, ear, cheek, chin), maculopapular rash, subcutaneous nodules
- Vision 20% - ANTERIOR UVEITIS, BLURRED VISION, ocular discomfort, photophobia, ciliary flush, floaters
- Cardiac - arrhythmias, cardiomyopathies
- Rheum - arthralgias, fever, malaise, wl
- Neuro - cranial nerve palsies (esp 7/facial), hypothalamic/pituitary lesions
- dx:
- TISSUE BX: NONCASEATING GRANULOMAS (= no central necrosis) - site skin, nodes, transbronchial
- CXR: BILAT HILAR LYMPHADENOPATHY, INTERSTITIAL LUNG DISEASE
- PFT: RESTRICTIVE (advanced)
- CT: hilar lymphadenopathy, ground glass, fibrosis (adv)
- Gallium scan: inc uptake in affected areas
- Bronchoalveolar lavage: r/o infx, inc CD4:CD8
- labs:
- INC ACE
- hypercalciuria/hypercalcemia (2ry to granuloma, inc vit d)
- Eosinophilia, leukopenia
- Cutaneous anergy - diminished skin reactivity to allergy
- tx:
- OBSERVE - MOST SPONTANEOUS REMISSION IN 2Y
- ORAL CORTICO - TX OF CHOICE IF NEEDED (worsening sx, deteriorating lung fx, decline - r/o tb, infx)
- Methotrexate
- Hydroxychloroquine - may be good for skin lesions
- NSAIDs for msk sx and erythema nodosum
pulmonary fibrosis (idiopathic fibrosing interstitial pneumonia)
CHRONIC PROGRESSIVE INTERSTITIAL SCARRING/FIBROSIS from persistent inflammation –> loss of pulmonary fx w/ restrictive component
-MC MEN 40-50y, smokers, survival <10y @ diagnosis
- sx:
- dyspnea or nonproductive cough (gradual onset)
- fine bibasilar inspiratory crackles, CLUBBING, +/-cyanosis
- dx:
- CXR/CT: DIFFUSE RETICULAR OPACITIES (HONEYCOMBING), GROUND GLASS OPACITIES
- BX: HONEYCOMBING
- PFT: RESTRICTIVE
- tx:
- no effective tx, smoking cessation, O2, steroids in acute exacerbation
- LUNG TRANSPLANT ONLY CURE
pneumoconioses / environmental lung diseases
CHRONIC FIBROTIC LUNG DISEASE SECONDARY TO INHALATION OF MINERAL DUST (ingested by alveolar macrophages, triggering inflam and release of chemical mediators –> parenchymal fibrosis –> restrictive lung disease and dec lung compliance
silicosis
- silica dust inhalation (mining, quarry work w/ granite/slate/quartz, pottery sandblasting)
- sx: asymptomatic +/- dyspnea on exertion, dry cough
- dx:
- CXR: muliple, small, NODULAR OPACITIES IN UPPER LOBES, +EGG SHELL CALCIFICATIONS OF HILAR/MEDIASTINAL NODES
- BX
- tx:
- no proven tx
- supportive: bronchodilators, O2, vaccinations +/-cortico
coal worker’s pneumoconiosis
-inhalation of dust from coal or carbon mines
- dx:
- CXR: SMALL, UPPER LOBE NODULES, HYPERINFLATION
- PFT: MAY BE OBSTRUCTIVE PATTERN
-tx: -supportive - bronchodilators, O2, vaccinations +/-cortico
CAPLAN SYNDROME
COAL WORKER’S PNEUMOCONIOSIS + RHEUMATOID ARTHRITIS
berylliosis
- electronics, aerospace, ceramics, tool and dye manufacturing, fluorescent light bulbs
- sx: dyspnea, cough, arthralgia, wl, fever
-dx:
-CXR: normal 50%, hilar lymphadenopathy, inc interstitial
+exposure, +beryllium lymphocyte proliferation test and noncaseating granulomas on bx
-tx: CORTICO, O2, supportive +/-methotrexate
byssinosis
“brown lung dx” or “monday fever” due to COTTON EXPOSURE in textile industry
-sx: dyspnea, wheezing, cough, chest tightness; worse at beginning of work week, improve over weekend
asbestosis
- seen 15-20 years after long-term exposure to asbestos; smoking inc risk of bronchogenic cancer
- INC RISK: BRONCHOGENIC CARCINOMA MC, MALIGNANT MESOTHELIOMA OF PLEURA
- sx: dyspnea on exertion, nonproductive cough
- dx:
- CXR: PLEURAL PLAQUES (THICKENING), INTERSTITIAL FIBROSIS (HONEYCOMBING), affects lower lobes primarily, +/- shaggy heart signs
- BX: may show linear asbestos bodies
-tx: -supportive, bronchodilators, O2, vaccinations +/-cortico
hypersensitivity pneumonitis / extrinsic allergic alveolitis
- Farmer/Cattle Worker –> moldy hay
- Ventillation –> water related contamination
- Bird Breeder –> bird feces, feathers, proteins
- Saw Mill –> sawdust from moldy redwood
- Metal worker –> contaminated metalworking fluids
- Mushroom –> moldy spores
- Grain worker –> exposure to wheat infested w/ weevils
- Chemical –> manufacture of plastics, polyurethane
PNEUMONITIS: generalized lung inflammation of the alveoli and respiratory bronchioles due to organic dusts, molds, foreign proteins and chemicals
Patho: INFLAMMATORY RX TO AN ORGANIC ANTIGEN
–> sensitization to the antigen; heavy exposure –> neutrophil activation in small airways and alveoli w/ mononuclear cell invasion
- sx:
- ACUTE: FEVERS, CHILLS, dyspnea, cough, tightness, malaise OCCURS 4-8H AFTER EXPOSURE
- SUBACUTE: GRADUAL DEVO OF DYSPNEA, PRODUCTIVE COUGH, anorexia, wl, usually no f/ch
- CHRONIC: progressive worsening of sx, slow-onset dyspnea, wl, clubbing, tachypnea
-dx:
-CXR:
Acute: diffuse micronodular interstitial pattern
Subacute/Chronic: micronodular opacities esp lower lung
-PFT’s: RESTRICTIVE
-CBC: LEUKOCYTOSIS W/ LEFT SHIFT
- tx:
- AVOID ALLERGEN, CORTICOSTEROIDS
silo filler disease
HYPERSENSITIVITY PNEUMONITIS FROM NITROGEN DIOXIDE GAS EXPOSURE RELEASED FROM PLANT MATTER
- sx:
- cough, dyspnea, fatigue, cardiopulmonary edema
- tx:
- reduce exposure (enter at top of silo), use N95 masks
mesothelioma (disease of pleura)
TUMOR ORIGINATING FROM PLEURA (80%), peritoneum, tunica vaginalis or pericardium
- 75% malignant - POOR PROGNOSIS
- 80% DUE TO CHRONIC ASBESTOS EXPOSURE
- sx:
- pleural mesothelioma - pleuritic chest pain, dyspnea, fever, night sweats, weight loss, hemoptysis
- bloody pleural effusions common
- dx:
- pleural bx via video-assisted thoracoscopy
- tx:
- local: pleurectomy (resection w/ margins)
- diffuse: resection, radiation and/or chemo
costochondirits and tietze syndrome (dz of pleura)
ACUTE INFLAM OF CHOSTOCHONDRAL, COSTOSTERNAL OR STERNOCLAVICULAR JOINTS
- sx:
- PLEURITC CHEST PAIN - intermittent, sharp, stabbing, WORSE W/ INSPIRATION, COUGHING OR CERTAIN MOVEMENTS, may radiate to shoulder
- LOCAL PAIN ON PALPATION, esp 2nd and 5th
- Costochondritis: NO PALPABLE EDEMA, palpation reproduces pain, MC
- Tietze Syndrome: LOCALIZED PALPABLE EDEMA, heat, erythema - mc effects 2nd and 3rd jx
pleural effusion
ABNORMAL ACCUMULATION OF FLUID IN PLEURAL SPACE (not dz itself, but sign of dz)
- Empyema: grossly purluent effusion (direct infx)
- Parapneumonic: noninfected 2ry to bacterial pneumonia
- Hemothorax: gross blood (trauma or malig)
- Chylothorax: inc lymph, turbid even after centrifuge
TRANSUDATE
- circulatory system fluid d/t either INC HYDROSTATIC OR DEC ONCONTIC PRESSURE
- CHF MC CAUSE (90%), NEPHROTIC SYNDROME, CIRRHOSIS, hypoalbuminemia, atelectasis
EXUDATE
- occurs when local factors INC VASCULAR PERMEABILITY (INFX, INFLAM)
- exudate is fluid that filters from circulatory system into areas of inflammation –> contains inc plasma proteins, WBCs, platelets +/- RBCs
- PULM EMBOLISMS usually exudative
- sx:
- ASYMPTOMATIC, dyspnea, pleuritic chest pain, cough
- DEC TACTILE FREMITUS, DEC BREATH SOUNDS, DULL PERCUSSION, +/- PLEURAL FRICTION RUB
- extreme cases may cause lung collapse or shift
-dx:
-CXR: PA/Lateral –> BLUNTING OF COSTOPHRENIC ANGLES + MENISCI SIGN (lateral decubitus films best)
-THORACENTESIS - TEST OF CHOICE - chem, cell count, cultures, cytology;
LIGHT’S CRITERIA EXCLUSIVE TO EXUDATES (any of 3 –> PROTEIN >0.5, LDH >0.6, LDH >2/3 UPPER LIMIT NRML)
-CT SCAN - used to confirm
- tx:
- treat underlying condition, diuretics, Na restrict
- THROACENTESIS - GOLD STANDARD (dx and tx), don’t remove more than 1.5 L per procedure
- CHEST TUBE AND DRAIN - IF EMPYEMA
- Pleurodesis - if malig or chronic (talc mc, doxy)
pneumothorax
-air in pleural space - INC POSITIVE PLEURAL PRESSURE CAUSES COLLAPSE OF THE LUNG
SPONTANEOUS
- atraumatic and idiopathic - BLEB RUPTURE
- Primary - no underlying lung disease, TALL, THIN MEN 20-40Y + FAMILY HISTORY
- Secondary - underlying lung disease (COPD, ASTHMA)
TRAUMATIC
-during CPR, thoracentesis, ventilation, subclavian line placement, car accident
TENSION
-positive air pressure pushes lungs, trachea, great vessels and heart to the contralateral side
- sx:
- CHEST PAIN, PLEURITIC, UNILATERAL NON-EXERTIONAL, sudden, DYSPNEA
- HYPERRESONANCE, DEC FREMITUS, DEC BREATH SOUNDS, unequal expansion, tachy/tachy
- TENSION = inc JVP, pulsus paradoxus, hypotn
- dx:
- CXR (expiratory view pref): DEC PERIPH LUNG MARKINGS, +/- COMPANION LINES
- tx:
- OBSERVE - IN PRIMARY SPONT IF SMALL (<15-20) at least 6h w/ repeat cxr; often resolves w/in 10d
- CHEST TUBE PLACEMENT (THORACOSTOMY) IF LARGE OR SEVERE
- NEEDLE ASPIRATION IF TENSION FOLLOWED BY CHEST TUBE PLACEMENT - placed in 2nd intercostal space at midclavicular line of affected side
pulmonary nodules
nodule < 3cm
mass > 3cm
Etiologies:
- GRANULOMATOUS INFX - TB, hysto, coccci
- TUMORS
- INFLAMMATION - RA, sarcoid, Wegener’s
- MEDIASTINAL TUMORS - THYMOMA MC
Benign:
- ROUND, SMOOTH
- SLOW GROWTH
- CALCIFICATIONS
- CAVITARY
Malignant:
- IRREGULAR, SPECULATED
- RAPID GROWTH (MAY DOUBLE 4 MO)
- CAVITARY W/ THICKENED WALLS
- dx:
- Observe - low malignant probability (<5%) if <50y and no smoking history
- Needle Aspiration or Bronchoscopy - if med risk; needle for peripheral lesions, bronch for central lesions
- Resection w/ Bx - preferred for high malig probability
bronchial carcinoid tumors
RARE NEUROENDOCRINE (ENTEROCHROMAFFIN CELL)TUMORS
- SLOW GROWTH, LOW METS, WELL-DIFFERENTIATED
- MAY SECRETE SEROTONIN, ACTH, ADH, MELANOCYTE STIMULATING HORMONE, MC <60Y
- sx:
- ASYMPTOMATIC 25-40%, focal wheezing, cough, recurrent pneumonia, hemoptysis
- SAIDH, CUSHING SYND, obstx
- CARCINOID SYNDROME: DIARRHEA (due to inc serotonin), inc bradykinin/histamine –> flushing, tachy, bronchoconstriction, hypotn, acidosis
- dx:
- BRONCHOSCOPY - PINK TO PURPLE WELL-VASCULARIZED CENTRAL TUMOR
- Tumor localization - CT and Octreotide scintography
- tx:
- SURGICAL EXCISION - DEFINITIVE
- often resistant to chemo/radiation
- OCTREOTIDE may be used to reduce symptoms (dec secretion of active hormones)
bronchogenic carcinoma
MC CAUSE OF CANCER DEATHS IN MEN AND WOMEN
- presents 50s-60s
- SMOKING MC CAUSE (includes 2nd hand), asbestosis
- METS MC TO BRAIN, BONE, LIVER, LYMPHS, ADRENAL
TYPES NON SMALL CELL CARCINOMA (85%):
ADENOCARCINOMA 35%
- MC IN SMOKERS, WOMEN AND NONSMOERS, typically PERIPHERAL, Bronchioalveolar (rare subtype w/ good prognosis)
- sx: GYNECOMASTIA
SQUAMOUS CELL 20%
-CENTRALLY LOCATED, CAVITARY LESIONS (central necrosis), HYPERCALCEMIA, PANCOAST SYNDROME
LARGE CELL (ANAPLASTIC) CARCINOMA 10% -VERY AGGRESSIVE
SMALL CELL (OAT CELL) CARCINOMA (13%)
- METS EARLY –> usually found on presentation, central, aggressive, SX NOT TX OF CHOICE
- sx: SIADH/Hyponatremia, CUSHING SYNDROME, LAMBERT-EATON SYNDROME (muscle weakness improves w/ continued use)
- SVC SYNDROME - dilated neck veins, facial plethora, prominent chest veins
- sx:
- asymptomatic, cough, hemoptysis, dyspnea, wl
- PANCOAST SYNDROME - TUMORS AT SUPERIOR SULCUS = SHOULDER PAIN, HORNER’S SYNDROME, ATROPHY OF HAND/ARM MUSCLES
- dx:
- CXR (incidental) and CT for staging
- SPUTUM CYTOLOGY for central lesions
- BRONCHOSCOPY for central lesions
- pleural fluid analysis
- NEEDLE BX for peripheral lesions
- tx:
- NON SMALL CELL - SX RESECTION TX OF CHOICE ESP IF LOCALIZED TO CHEST
- SMALL CELL - CHEMO TX OF CHOICE +/-radiation
pulmonary embolism
- thrombus in pulmonary artery or its branches
- 95% of PEs come from DVTs in lower extremities above the knee or pelvis (other from fat emboli from long bone frx and air emboli from central lines)
- sx:
- DYSPNEA AND TACHYPNEA MC
- Hx Classic Triad: DYSPNEA, PLEURITIC HEST PAIN, HEMOPTYSIS
- Post-op pt presentation: SUDDEN TACHYPNEA, COUGH, HEMOPTYSIS
- PULM EXAM USUSALLY NORMAL
- dx:
- HELICAL CT SCAN (CT-PA) BEST INITIAL TEST FOR SUSPECTED PE –> intraluminal defect
- V/Q SCAN - only rules out PE in pt w/ low suspicion
- PULM ANGIOGRAPHY GOLD STANDARD
- DOPPLER US - 70% w/ PE will be + LOWER EXTREMITY DVT
- ancillary evaluation tests:
- CXR: usually normal (normal cxr in setting of hypoxia is suspicious for PE) WESTERMARK’S SIGN (avascular markings distal to area of embolus) HAMPTON’S HUMP (wedge-shaped infiltrate rep infarction)
- ECG: SINUS TACHY AND NONSPP ST/T CHANGES MC
- ABG: INITIALLY RESPIRATORY ALKALOSIS –> respiratory acidosis may occur w/ time
- D-DIMER - high sensitive, poor specificity
PE LIKELY –> HELICAL CT SCAN –> +/- –> PULM ANGIO
PE UNLIKELY –> D DIMER –> if pos –> HELICAL CT
management of pulmonary embolism
ANTICOAGULATION:
- Low Molecular Weight Heparin
- Unfractionated Heparin –> need to monitor PTT, higher risk of HIT
- WARFARIN FOR AT LEAST 3 MONTHS
- Novel Anticoagulants (hep bridge to Dibigatran or Edoxaban)
IVC FILTER: hemodynamically STABLE PT IN WHOME ANTICOAGULATION IS C/I OR IS UNSUCCESSFUL (no long-term reduction of mortality)
THROMBOLYSIS OF CLOT: Streptokinase, Urokinase, Alteplase –> MASSIVE PE, HEMODYNAMICALLY UNSTABLE PE, resolves emboli w/in 24h
-C/I in CVA or internal bleed w/in 2 mo; relative: uncontrolled htn, sx/trauma w/in 6 weeks
THROMBECTOMY/EMOLECTOMY: unstable/massive PE if thrombolysis c/i or ineffective
HEMO STABLE –> IV UNFRACTIONED HEPARIN OR SQ LMWH + PO WARFARIN OR NOVEL @ least 3 months
HEMO STABLE W/ ANTICOAG C/I –> IVC FILTER
HEMO UNSTABLE –> THROMBOLYTIC TX
HEMO UNSTABLE W/ THROMBOLYITCS C/I –> EMBOLECTOMY
PE prophylaxis
-warranted preop in patients undergoing surgery w/ prolonged immobilization, pregnant women, h/o DVT/PE
- EARLY AMBULATION: low risk, minor procedures in patients <40y
- ELASTIC STOCKINGS / SCDS: mod risk
- LOW MOL WEIGHT HEPARIN: pt undergoing orthopedic or neurosurgery, trauma
PERC Criteria
Pulm Embolism Rule out Criteria
-if all following negative, you can effectively r/o PE if low suspicion:
Age <50y Pulse <100 bpm O2 sat >95% No prior PE No recent trauma or surgery No hemoptysis No use of exogenous estrogen No unilateral leg swelling
pulmonary hypertension
mean pulm arterial pressure >25mmHg at rest (normal <20) or >30 during exercise
-INC PULM VASC RESISTANCE –> RVH –> R-SIDED HF
I: IDIOPATHIC PULM ARTERIAL HTN (PRIMARY)
II: Pulm HTN due to left heart disease
III: Pulm HTN due to hypoxemic or chronic lung disease
IV: Pulm HTN due to chronic thromboembolic disease
PRIMARY: IDIOPATHIC
-MC MIDDLE-AGED OR YOUNG WOMEN, ave 50y
BMPR2 gene defect - rare
SECONDARY: 2ry to pulm disease (COPD MC, sleep apnea, PE)
-sx:
-DYSPNEA, chest pain, weakness, fatigue, cyanosis, edema
-ACCENTUATED S2
-SIGNS OF R-SIDED HEART FAILURE (INC JVP, PERIPH EDEMA, ASCITES)
+/- systolic ejection click, pulm regurge, right vent heave
- dx:
- CXR: enlarged pulm arteries, interstitial edema
- ECG: COR PULMONALE, RVH, RIGHT AXIS DEVIATION, right atrial enlargement, right bundle branch block
- ECHO: large right ventricle, right atrial hypertrophy
- R-SIDED HEART CATH - DEFINITIVE DX - GOLD STD: mean pulm artery pressure 25+mmHg at rest
- CBC: POLYCYTHEMIA w/ INC HCT
- tx:
- Primary: vasoreactive trial (nitric oxide, IV adenosine or ccb); IF VASOREACTIVE –> CCB 1ST LINE FOR PRIMARY
- heart-lung transplant definitive
- Type II: tx underlying disease
- Type III: O2 only tx to reduce mortality, tx underlying
- Type IV: anticoag first line; tx underlying
pneumonia - micro
MICROASPIRATION OF OROPHARYNGEAL SECRETIONS IS MC ROUTE OF INFX
STREP PNEUMO - MC CAUSE OF COM ACQUIRED
HAEMOPHILUS INF - 2nd mc cause of CAP (inc w/ underlying pulm disease, copd, bronchiectasis, cf, children <6, elderly) GNR
Mycoplasma Pneumo - mc cause of atypical (WALKING PNEUMONIA) esp <40y, inc school-aged, college, military
-PHARYNGITIS, BULLUS MYRINGITIS (ear) - lacks cell wall so doesn’t respond to beta-lactams
Staph Aureus - often seen after viral illness (flue)
Klebsiella Pneumo - severe illness in ETOHics, debilitated, chronic illness, aspirators; CAVITARY LESIONS - GNR
Anaerobes - ASPIRATION pneumonia; MC R-lower lobe
Pseudomonas - IMMUNOCOMPROMISED (hiv, neutropenic, s/p transplant, cf, bronchiectasis)
—-VIRAL—-
RSV + PARAINFLUENZA - MC CAUSE INFANTS/CHILDREN
INFLUENZA - MC ADULTS
CMV - transplant recipients and pt w/ AIDS
Varicella-Zoster - severe in adults
—-FUNGAL/PARASITES—-
Pneumocystis jirovecii - compromised host, O2 desat w/ ambulation
Histoplasma - OH + Mississippi River Valley - soil w/ bird/bat droppings
Coccidioides - found in soil of southwest US
pneumonia - mc by setting
Community-Acquired: from outside hospital setting (not at nursing home) OR pt that was ambulatory prior to admission and develops pneumonia w/in 48h of admission
- STREP PNEUMONIAE MC
- mycoplasma, chlamydiophilia, viral (esp young, healthy)
- H. influenzae, M. catarrhalis (esp w/ COPD)
- Legionella
- Klebsiella and other GRN (esp ETOHics)
- S. aureus
Hospital-Acquired: occurring >48h after admission
- GNRs: PSEUDOMONAS
- E. coli, Klebsiella, Enterobacter, Serratia, Acinetobacter
- also concern for S. aureus (esp MRSA)
Immunocompromised
- cover for same as hospital-acquired
- added coverage against PCP, fungi, nocardia, atypical mycobacterium and viruses HSV and CMV
Aspiration
-PNEUMONITIS: d/t aspiration of acidic gastric contents
-PNEUMONIA: d/t inhalation of oropharyngeal microbes
Outpatients: typical oral flora (staph, strep, anaerobes)
Inpatient or chronic ill: GNRs, staph
pneumonia symptoms
TYPICAL
- S. PNEUMO, H. influenzae, Kelbsiella, S. aureus
- CXR: LOBAR
- sx:
- sudden onset fever, productive cough w/ purulent sputum, pleuritic chest pain
- RIGORS (ESP S. PNEUMO), tachy/tachy
- SIGNS OF CONSOLIDATION: BRONCHIAL BREATH SOUNDS, DULLNESS ON PERCUSSION, INC TACTILE FREMITUS, EGOPHONY, inspiratory rales/crackles
ATYPICAL
- MYCOPLASMA, chlamydophila, legionella, viruses
- CXR: DIFFUSE, PATCHY interstitial or reticulonodular infiltrates
- sx:
- low-grade fever, dry non-productive cough
- EXTRAPULMONARY SX: myalgias, malaise, sore throat, headache, n/v/d
- PE OFTEN NORMAL +/-crackles, rhonchi, signs of consolidation usually absent
pneumonia diagnosis
CXR/CT SCAN
- cxr may lag behind clinical improvement for weeks
- pleural effusion may be present (exudative)
- abscess –> staph, klebsiella, anaerobes
- upper lobe (esp R) w/ bulging fissure, cavitations –> klebsiella
SPUTUM (gram stain/culture)
- RUSTY/BLOOD-TINGE –> STREP PNEUMO
- CURRANT JELLY –> KLEBSIELLA
- green sputum –> H. flu, pseudomonas
- foul-smelling –> anaerobes
CHLAMYDOPHILA –> hoarseness, fever –> resp sx after few days –> send IgM, IgG titers
MYCOPLASMA –> ear pain, BULLOUS MYRINGITIS, erythematous pharynx or tympanic membranes, persistent nonproductive cough –> send serum cold agglutinins
LEGIONELLA –> ASSOC W/ GI SX, INC LFTs, HYPONA –> send legionella urine antigen +/-PCR
pneumonia treatment
Hospitalize if multi-lobar, + neutropenia or pt w/ comorbidities that may complicate treatment
COM-ACQUIRED OUTPATIENT
- MACROLIDE OR DOXY 1ST LINE
- FQ if comorbid conditions/recent abx use
COM-ACQUIRED INPATIENT
- B LACTAM + MACROLIDE (OR DOXY)
- OR BROAD-SPEC FQ
COM-ACQUIRED IN ICU
- B LACTAM + MACROLIDE
- OR B LACTAM + BROAD SPEC FQ
- if B-lactam allergy: fq + aztreonam
HOSPITAL ACQUIRED
- ANTI-PSEUDOMONAL B-LACTAM + ANTI-PSEUDOMONAL AG or FQ
- add VANC or LINEZ if MRSA suspected
- add LEVO or AZITHRO if LEGIONELLA suspected
- add BACTRIM +/- CORTICO if PCP suspected
- if B-lactam allergy: fq + clinda
ASPIRATION
-clinda or metronidazole or augmentin
+supplemental O2, IV fluids, respiratory isolation (if suspect TB)
MEDS:
B-lactams: CEFTRIAXONE, cefotaxime, amp/sulb (Unasyn) or Ertapenem
Anti-Pseudomonal B-lactams: PIP/TAZO, CEFEPIME, Imipenem, Meropenem, Ceftazidime
Macrolides: Clarithromycin, Azithromycin
Respiratory FQ: LEVO, MOXI, Gemi (cipro not respiratory fq, may be used for pseudomonas or legionella)
Aminoglycosides: Amikacin, Gentamicin, Tobramycin
physical exam - lung ddx
Pneumonia:
- percussion - dullness
- fremitus - INCREASED
- breath sounds - BRONCHIAL, EGOPHONY
Pleural Effusion:
- percussion - dullness
- fremitus - decreased
- breath sounds - decreased
Pneumothorax or Obxt Lung Dz:
- percussion - HYPERRESONANCE
- fremitus - decreased
- breath sounds - decreased
pneumococcal vaccines
PCV13 - Pneumo Conjugate Vac (Prevnar)
- USED IN CHILDHOOD VACCINATION
- healthy children <24 mo given 4 doses: 2, 4, 6, 12-15 mo
- high-risk children 2+ should also receive a single dose of PPSV23 at least 8 weeks after completed PCV13 series
PPSV23 - Pneumo Polysaccharide Vaccine (Pneumovax)
- AGE 65+ - if received a dose prior to 65, should get one at 65 if 5+ years have passed
- Age 2-64 W/ CHRONIC DZ: cardiac, pulm, dm, etoh, liver dz, chronic care facility, immunocomp –> single revaccination if 5+ years elapsed since 1st dose
- SE: local pain, erythema at site, F, myalgias
tuberculosis
GRANULOMA FORMATION
high risk:
-inc risk exposure: close contacts of pt w/ active, healthcare workers
-inc risk infx: immigrants from high-prev areas, homeless
-inc risk active after infx: immunodeficient
Patho: inhale airborne droplets –> mycobacterium reaches the alveoli and ingested by macrophages, mtb may remain viable w/ing macrophage and bypass immune system
Primary TB: outcome of initial infx
-Primary Rapidly Progressive: active initial infx w/ clinical progression –> are CONTAGIOUS! common in kids (esp <4y) in endemic areas
Chronic (latent) Infx: 90% control - intial primary infx via granuloma formation (may become caseating); usually become PPD +2-4 weeks after infx, not infectious
Secondary (reactivation) TB: reactivate w/ waning immune defenses (elderly, hiv, steroids, malig) 5-10% lifetime
-MC local in apex/upper lobes /w cavitary lesions - CONTAGIOUS
-sx:
Pulmonary TB:
-chronic productive cough, chest pain, +/-hemoptysis
-night sweats, f/ch, fatigue, weight loss
-SIGNS OF CONSOLIDATION, rales, rhonchi near apices, dullness
Extra-pulmonary TB:
-can affect any organ
-VERTEBRAL (POTT’S DISEASE)
-LYMPH NODES (SCROFULA)
-tb meningitis, pericarditis, peritonitis, jts, kidney, adrenal
TB screen and diagnosis
PPD
5+ mm –> positive in HIV, IMMUNOSPPRESED, CLOSE CONTACTS OF PT W/ ACTIVE TB, CXR CONSISTENT W/ OLD/HEALED TB (calcified granuloma)
10+ mm –> positive in ALL OTHER HIGH-RISK POPULATIONS/HIGH PREVALENCE POPULATIONS
15+ mm –> positive in EVERYONE ELSE (NO KNOWN RF)
False Negative:
-ANERGY (HIV, SARCOID), FAULTY APPLICATION (sq instead of td), acute (takes 2-10w to convert), malig
False Positive:
-IMPROPER READ, CROSS-RX W/ ATYPICAL (MAC), q/in 2-10y of BCG vaccination
Booster Effect:
-infected person’s immune system “forgets” about TB until years later when testing “reminds” immune system. next ppd will be pos bc of initial infx but not bc recently converted –> confirm w/ 2-step PPD
-dx:
ACID-FAT SMEAR AND SPUTUM CULTURE
-AFB CX GOLD STD
-tb ruled out after 3 neg smears
CXR: indicated to EXCLUDE ACTIVE TB, YEARLY SCREEN IN PT W/ KNOWN +PPD OR R/O ACTIVE
- Reactivation: apical (upper lobe) fibrocavitary disease
- Primary: middle/lower lobe consolidation
- Miliary: small, MILLET-SEED nodular lesions (2-4mm)
- Pleurisy: pleural effusion caused by tb infx
- Granuloma: residual evid of healed primary tb
INTERFERON GAMMA RELEASE ASSAY
-blood test QUANT-GOLD
tb treatment
LATENT
-INH + PYRIDOXINE (vit B6) X 9 MONTHS
Alt: RIF x 4 months OR INH + Rifapentine
-If HIV: INH + PYRIDOXINE (vit B6) X 12 MONTHS
ACTIVE
- Initial 4 Drugs X 2 months: RIFAMPIN + ISONIAZID + PYRAZINAMIDE + ETHAMBUTOL (or streptomycin)
- TOTAL TX FOR 6 MONTHS (contine RIF + ISO)
- respiratory isolation - not considered infectious after 2w
- Isoniazid prophylaxis given to children <4y w/ exposure
RIFAMPIN
-THROMBOCYTOPENIA, ORANGE COLORED SECRETIONS
ISONIAZID (INH)
-HEPATITIS (esp >35y), PERIPHERAL NEUROPATHY (prevent w/ pyridoxine/B6), drug-induced lupus
PYRAZINAMIDE
-HEPATITIS AND HYPERURICEMIA (caution in gout or liver dz), PHOTOSENSITIVE DERM RASH
ETHAMBUTOL
-OPTIC NEURITIS (color perception prob, vision change), PERIPHERAL NEUROPATHY
STREPTOMYCIN
-aminoglycoside, OTOTOXIC, NEPHROTOXIC
acute bronchitis
INFLAMMATION OF TRACHEA/BRONCHI, OFTEN FOLLOWS URI
- MC CAUSED BY VIRUS: ADENOVIRUS, parainfluenza, coronavirus, coxsackie, rhinovirus, rsv
- bacteria: s. pneumo, h. influenzae, m. catarrhalis, mycop
- sx:
- HALLMARK IS COUGH +/-productive, +/1 lasts 1-3wk
- dx:
- clinical, if pneumonia suspected order cxr
- CXR normal or nonspecific
- tx:
- SYMPTOMATIC TX OF CHOICE: fluids, rest, bronchodilators, antitussives only in adults
- ABX NO STATISTICAL BENEFIT IN HEALTHY PT, +/-benefit in elderly, copd, immunocompromised or cough >7-10 days
pertussis
HIGHLY CONTAGIOUS INFX 2RY TO BORDETELLA
- sx:
- 7-10 day incubation
- CATARRHAL PHASE (uri sx, most contagious) –> PAROXYSMAL PHASE (severe coughing fits w/ inspiratory whooping sound after cough fits, post coughing emesis)
- -> CONVALESCENT PHASE (resolution of cough - may last up to 6 weeks)
- dx:
- PCR OF NASOPHARYNGEAL SWAB - GOLD STD
- LYMPHOCYTOSIS (60-80% dif), WBC up to 50K
- tx:
- SUPPORTIVE: oxygen, nebulizers, vent
- ABX used to dec contagiousness of pt (only shortens duration w/in first week) - MACROLIDES (ERYTH, azith)
- bactrim 2nd line
- complications:
- PNEUMONIA, encephalopathy, otitis media, sinusitis, seizures; inc mortality in infants due to apnea/cerebral hypoxia w/ coughing fits
bronchiolitis
INFLAM OF BRONCHIOLES
ACUTE
-MC CHILDREN 2 mo - 2 yr AFTER VIRAL INFX (ESP RSV, ADENOVIRUS) d/t neutrophil infiltration of bronchioles –> narrowing
BRONCHIOLITIS OBLITERANS (CONSTRICTIVE)
- patchy chronic inflammation and fibrosis of bronchioles –> collapse/obliterate bronchioles, granulation tissue in bronchiole lumen –> obxt lung disease
- mc seen post-lung transplant rejection, inhalation injuries, drug rx, RA
- TX: CORTICO + IMMUNOSuPRESS, lung transplant definitive
CRYPTOGENIC ORGANIZING PNEUMONIA
- persistent alveolar exudates –> inflam and fibrosis of bronchioles and alveoli; looks like pneumonia on cxr but doesnt respond to abx
- TX: CORTICO
acute bronchiolitis
LOWER RESPIRATORY TRACT INFX OF SMALL AIRWAYS –> prolif/necrosis of bronchiolar epithelium produces obst from sloughed epithelium, inc mucus plugs, submucosal edema –> PERIPERHA AIRWAY NARROWING AND VARIABLE OBSTX
- RSV MC CAUSE (50-70%)
- adeno, flu, parainfluenza, mycoplasma
- RF: INFANTS <2 MC AFFECTED, <6 mo age, exposure to cigarettes, lack of breastfeeding, premature, crowded conditions
- Complications: otitis media w/ s. pneumo mc acute cx (asthma mc later in life)
- sx:
- FEVER, URI SX 1-2 DAYS –> RESPIRATORY DISTRESS (wheezing, tachypnea, nasal flaring, cyanosis, rales)
- dx:
- CXR: hyperinflation, peribronchial cuffing
- nasal washings using monoclonal Ab testing
- PULSE OX BEST PREDICTOR OF DZ IN KIDS (<96 admit)
- tx:
- Supportive: humidified O2 mainstay, fluids, acetaminophen/ibuprofen
- Meds: +/- B-agonists, +/- nebulized epi
- Ribavirin +/- if severe lung or heart dz or immunosuppressed pt
-PALIVIZUMAB PROPHYLAXIS IN HIGH-RISK GROUPS
acute epiglottitis
HAMOPHILUS INBLUENZAE TYPE B (HIB) MC
- rare: s.pneumo, s.aureus, s.pyogenes - mc in adults
- mc children 3mo - 6y, males 2x mc
- sx:
- 3 Ds: DYSPHAGIA, DROOLING, DISTRESS
- fever, odynophagia, inspiratory stridor, dyspnea, hoarseness, muffled voice, TRIPODING
- suspect w/ rapid devo pharyngitis, muffled voice and odynophagia out of proportion
- dx:
- LARYNGOSCOPY - DEFINITIVE: cherry-red
- Lateral cervical xray: THUMB SIGN
- tx:
- maintain airway and supportive: dexamethasone, tracheal intubation in severe
- ABX: 2nd/3rd GEN CEPHALOSPORINS: CEFTRIAXONE OR CEFOTAXIME
laryngotracheitis (croup)
INFLAM MC 2ry TO ACUTE VIRAL INFX OF UPPER AIRWAY (larynx, subglottis, trachea) –> SUBLOTTIC LARYNX/TRACHEA SWELLING –> stridor, BARKING
- PARAINFLUENZA 1 MC CAUSE, adenovirus, rsv, rhinovirus, diphtheria rare
- 15% children experience croup in childhood, fall/winter
- sx:
- BARKING COUGH
- STRIDOR - inspiratory and expiratory (worse w/ crying)
- HOARSENESS d/t laryngitis
- DYSPNEA - worse at night +/-URI sx
- dx:
- clinical (r/o epiglottitis and foreign body aspiration)
- FRONTAL CERVICAL RADIOGRAPH: STEEPLE SIGN
- tx:
- Mild (no stridor at rest): cool humidified air mist, hydration, DEXAMETHASONE will give relief
- Mod (stridor w/ rest but mild retractions): DEXAMETHASONE PO/IM, +/-nebulized epi
- Severe (stridor at rest + marked retractions): DEXAMETHASONE + NEB EPI + HOSPITALIZATION
influenza
antivirals vs A + B: NEURAMINIDASE INHIBITORS
- OSELTAMIVIR (TAMIFLU)
- Zanamivir - diskhaler
- Ribavirin
antivirals vs A (widespread resistance, not used)
-Amantadine, Rimantadine
Vaccine:
C/I: EGGS, GELATIN, THIMEROSAL ALLERGIES
Trivalent
- 65+ (50+ by some sources)
- underlying med conditions: asthma, copd, sickle cell, heart, dm
- contacts of pt infected w/ flu
- residents of nursing home/long-term care
- healthcare workers, immunocompromised
- women pregnant during flu season
Intranasal (live attenuated) - not routinely used
- Ind: healthy pt 2-49y
- C/I: 50+, pregnant, immunocompromised, dm, chronic lung/heart dz, egg allergy, hx GB
foreign body aspiration
MC ON RIGHT SIDE (due to wider, more vertical and shorter right main bronchus)
- sx:
- coughing, choking, wheezing, hemoptysis
- may devo aspiration pneumonia
- gastric aspiration may cause ARDS
- dx:
- BRONCHOSCOPY - DIRECT VISUALIZATION AND REMOVAL
- CXR: regional hyperinflation
acute respiratory distress syndrome
LIFE-THREATENING ACUTE HYPOXEMIC RESPIRATORY FAILURE (can lead to organ failure bc of hypoxia)
-MC DEVO IN CRITICALLY ILL PT (SEPSIS, trauma, aspiration of gastric contents)
-inflam lung injury d/t pro-inflam cytokines –> diffuse alveolar damage –> inc permeability of alveolar-capillary barrier –> pulmonary edema, loss of surfactant and vascular endothelial damage –> dec blood O2
- sx:
- acute dyspnea and hypoxemia
- multi-organ failure if severe
-dx: 3 components: -SEVERE REFRACTORY HYPOXEMIA IS HALLMARK -bilateral pulmonary infiltrates on cxr -absence of cardiogenic pulmonary edema/chf <18mmHg
- ABG: PaO2/FIO2 ratio <200mmHg and NOT RESPONSIVE TO 100% O2 (REFRACTORY)
- CXR: DIFFUSE BILAT PULM INFILTRATES –> white-out pattern; SPARES COSTOPHRENIC ANGLES
- CARDIAC CATHETERIZATION OF PULM ARTERY (SWAN-GANZ): PCWP <18mmHg (normal 12-18)
- high pcwp in pulmonary edema (>18)
- tx:
- NONINVASIVE OR MECH VENTILATION, TX UNDERLYING CAUSE
- CPAP w/ full face mask, keep O2 >90%
- Positive End Expiratory Pressure (PEEP) - prevents airway collapse at end-expiration, increases FRC, dec shunting and expands alveoli for inc diffusion
sleep apnea
RF: OBESITY MC, mc 6th/7th decades, men
CENTRAL: reduced CNS respiratory drive leads to dec respiratory effort
OBSTRUCTIVE: physical airway obstx - compression, dec pharyngeal muscle tone, inc tonsils or deviated septum
- sx:
- snoring, unrestful sleep, nocturnal choking
- large neck circumference, crowded oropharynx, micrognathia
-dx:
-IN-LAB POLYSOMNOGRAPHY - 1ST LINE DIAGNOSTIC
15+ events/hr: obstx or mixed, hyponeas, respiratory effort arousals
-Labs: polycythemia (chronic hypoxemia)
-Epworth sleepiness scale
- tx:
- CPAP (cont positive airway pressure) - MAINSTAY
- Bx: WL, exercise, abstain alcohol, sleep position
- oral appliances
- surgical correction: tracheostomy definitive, nasal septoplasty, etc
normal breath sounds
Bronchial: loud high-pitched heard over trachea and larynx; EXPIRATION > INSPIRATION
Bronchovesicular: med-pitched sounds heard over the primary bronchus and posteriorly btw scapula; EXPIRATION = INSPIRATION
Vesicular: soft, gentle over all areas; INSPIRATION > EXP
abnormal breathing
CHEYNE-STOKES
- CYCLIC BREATHING IN RESPONSE TO HYPERCAPNIA
- smooth increases in respirations and then gradual decrease in respirations w/ period of apnea 15-60 sec
- d/t DEC BRAIN BLOOD FLOW, slow impulses to resp center
BIOT’S BREATHING
- IRREGULAR RESPIRATIONS (QUICK SHALLOW BREATHS OF EQUAL DEPTH) W/ IRREGULAR PERIODS OF APNEA
- can be seen w/ damage of MEDULLA OBLONGATA or OPIOID USE
KUSSMAUL’S RESPIRATION
-hyperpnea - DEEP, RAPID, CONTINUOUS RESPIRATIONS as a result of METABOLIC ACIDOSIS, no expiratory pause
acidosis/alkalosis
Lungs:
- CO2 REGULATION via resp rate
- ACIDOSIS STIMULATES INC RESPIRATION (BLOW OFF CO2)
- ALKALOSIS DEPRESSES RESPIRATION (RETAIN CO2)
Kidneys:
- GENERATES NEW HCO3 BY ELIM H+
- REABSORBS VIRTUALLY ALL FILTERED HCO3
metabolic acidosis
ANION GAP - too much acid or too little bicarb
“mudpiles”
METHANOL UREMIA DKA / ALCOHOLIC KA PROPYLENE GLYCOL ISONIAZIDE, INFX LACTIC ACIDOSIS ETHYLENE GLYCOL RHABDO / RENAL FAILURE SALICYLATES
NON-GAP - too much acid or too little bicarb
-lost bicarb replaced by Cl- (so no change in AG)
"hardups" HYPERALIMENTATION ACETAZOLAMIDE RENAL TUBULAR ACIDOSIS DIARRHEA URETERO-PELVIC SHUNT POST-HYPOCAPNIA SPIRONOLACTONE
metabolic alkalosis
-little acid or too much bicarb
"clever pd" CONTRACTION LICORICE ENDO (CONN'S, CUSHING) VOMITING EXCESS ALKALI REFEEDING ALKALOSIS POST-HYPERCAPNIA DIURETICS
respiratory acidosis
-anything that decreases respiration
"champp" CNS DEPRESSION (DRUGS/CVA) HEMO/PNEUMOTHORAX AIRWAY OBSTX MYOPATHY PNEUMONIA PULMONARY EDEMA
respiratory alkalosis
-anything that causes hyperventilation
"champs" CNS DISEASE HYPOXIA ANXIETY MECH VENTILATORS PROGESTERONE SALICYLATES/SEPSIS
