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liveonearth ([personal profile] liveonearth) wrote2008-11-09 07:42 pm
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CPD: Respiratory Hypersensitivity, Collagen Vascular Dz, Fungal Infx, Croup, TB, ARDS, Sleep Apnea


Hypersensitivity dz of the lungs: (Ag = antigen)
--type I: (atopic/anaphyllactic) allergic asthma w/ histamine release from mast cells after contact with Ag
--type II: (cytotoxic) eg: Goodpasture's dz with complement-Ab causing cell lysis
--type III: (immune-complex mediated) eg: SLE assoc w/ Ab-Ag complexes
--type IV: (cell mediated/delayed) eg: tuberculin skin test from release of lymphokines following Ag contact

Hypersensitivity pneumonitis = chronic or recurrent cough and SOB or hx of recurrent episodes of acute resp sx, fever, chills, dry cough, chest tightness malaise, ill, tachypnea, crackles @ lung base, ...when subacute more gradual onset, weight loss and low grade fever, possible cyanosis, when chronic insidious onset also may show digital clubbing, inspiratory squawk or chirping rales. Allergic response after inhalation of something, onset 4-6 hours after exposure, esp w/ hx of recurrent pneumo (esp reg or w/ pattern), resp sx after move, contact with birds, water damage to home or other living space, use of hot tub, sauna, swim pool (chlorine), exposure to other people w/ sx, improvement of condition during vacations or other absence. Etio: cotton, flax, bagasse, hemp, coffee, bean dust, animal dander, cheese mold, hay, maple bark, cedar oil, birds, mold saw dust, wheat flour, brewer's yeast, mites, ETC.

Collagen vascular dz = several diseases including Rheumatoid arthritis (pleural effusion, nodules, fibrosis, vasculitis), Lupus (same sx plus nodules, Sjogrens, polymyositis, dermatomyositis, scleroderma, polymyalgia rhematica, poly-arteritis), and Wegener's Granulomatosis (focal destruction and infiltration of veins and arteries, mb asx or fever, wt loss, cough, dyspnea, chest pain)

PIE = pulmonary infiltrates with eosinophilia = allergy to parasites or allergic rxn to drugs, MOLDS, FUNGI, looks a lot like pneumonia, astham, or collagen vascular change. DX: need travel history, assess for risk of fungal or parasitic infx, travel to Asia, Africa, Latin America, South America, or SE US. Most common ETIO: filaria, drug rxn, intestinal parasites (ascaris lubricoides, roundworm), rxn to candida albicans or bacillus bact, aspergillus fumigatus

Goodpasture's = pulmonary hemorrhage with severe and progressive glomerulonephritis, usu in young men, presents with severe HEMOPTYSIS with Fe deficiency, dyspnea, progressive deadly renal failure

CROUP = viral inflam of upper and lower resp tract, sx dt inflam response, begins with mild URI prodrome, coryza, nasal congestion, sore throat, cough, low fever, most in kids 6 mo-3 yr, 2:1 males, most common in autumn, SPASMODIC COUGH harsh, brassy, seal-like, repiratory stridor at night, mild expiratory wheezing, often improves with change in air temp (go outside, or go in steamy shower), may have anxiety/lethargy/agitation dt hypoxia, if severe see tachypnea, tachycardia out of proportion to fever, lethargy pallor, hypotonia. Usual peaks in 3-5 days and resolves in 4-7. Homeop sequence: aconite, spongia, hepar sulf. LABS: leukocytosis with shift to left. DX: AP x-ray of C-spine, steeple sign (constricted trachea below glottis) suggests croup. Very rarely can result in death from complete airway obstruction. DDX: Distinguish from epiglottitis (hot potato voice, high fever, emergency and dont' look!), foreign body obstructoin, rare bacterial infx incl retrapharyngeal abscess, see on lat xray, diptheria (R/o if vaccinated).

TUBERCULOSIS = chronic cough with mycobacterium (acid fast organism, Ziehl-Neelsen stain to see "red snappers"), trans via longterm exposure to resp droplets (8 hrs/day x 6 mo or 24 hrs/day x 2 mo => 50% chance of infx), internationally common, spreads thru lymph and blood to any organ but usu found in lungs, many exposed peeps never have sx, bacteria an stay inactive, increasing in prevalence esp in SE Asia, E Asia, Sub-saharan Africa. Men 2x women. Most in 25-44 years old, minorities. 3 types: human, bovine, avian. Primary infx is like a flu, reactivation is usual presentation: chronic cough, yellow-green sputum, malaise/fatigue, anorexia, fever in late afternoon regular paroxysmal, night sweats, pleuritic pain. DX: chest xray (classic caseating granulomatous lesion in posterior right upper lobe, apicooposterior segment of left upper lobe, apical segments of lower lobes), sputum sample (3-6 weeks to grow) and quantiferon B serum test. PPD Mantoux skin test not standard anymore: positive test in 80% of pts with 2ndary TB. Up to 20% of pts with active TB may be asx. PE: fever, hypoxia, lymphadenopathy, cachexia, tachycardia, abnormal lung sounds. WBC's usu normal. DDX: pneumonia, lung abscess, pulmonary mycosis, CA, non-TB mycobacterium). Tx: individual meds not effective so take 2-4 different meds up to a year, meds make pts feel bad so low compliance.

PLEURISY = infx of pleura dt bact, TB, fungus, parasites, virus, inhaled chems or toxins, collagen vasc dz, cancer, tumors of pleura (mesothelioma, sarcoma), CHF, pulmonary embolism, obstruction of lymph oft dt lung tumor, trauma (rib fx or irrit from chest tubes), drugs, abdominal prob (pancreatitis, cirrhosis of liver), lung infarction....ETC. PATIENT PRESENTS with hand over lung, shallow breathing. Usudt unresolve pneumonia. S/Sx: usu sudden onset, non-specific pain, vague or stabbing, pain increase with cough/deep breath, rapid shallow breathing, splinting, bending over, referred pain to shoulder or diaphragm, effusion may cause pain to subside but may casue dyspnea. USU ON R SIDE, IF ON LEFT: pericarditis? angina??. PE: limited motion on affected side, decreased breath sound, pleural friction rub is characteristic but may not be present at onset, also counds from crackles to harsh grating, creaking, leather sounds usu on expiration or inspiration. IMAGING: xray may be normal or may see fluid blunting of costo-phrenic angle with effusion, ultrasound can detect pleural fluid, CT scane can detect trapped pockets of pleural fluid. DX: removal of pleural fluid with aspiraiton, see fluid color, consistency, clarity, presence of infx orgs/cancer cells. Fluid is exudate or transudate. DDX: acute abdomen (N/V, pain), intercostal neuritis (no friction rub), costo-chondritis, herpes, MI, pneumothorax (r/o by xray), pericarditis.

Exudate = dt pleural inflam with increased permeability of pleural surface to protein, high in proteins, low in sugar, high in LDH enzyme, high WBC's. ETIO: parapneumonic, malignancy, pulmonary embolism, collagen-vascular, TB, asbestos, trauma, pancreatitis, postcardiac injury syndrome, esophageal perforation, radiation pleuritis, drug induced, SARCOIDOSIS.

Transudate = normal levels of the above in plasma fluid forced out of its normal space by high microvascular pressure or low oncotic pressure: ETIO: CHF, cirrhosis, atelectaiss, hypoalbuminemia, nephrotic syndrome, peritoneal dialysis, mysedema, constrictive pericarditis

Pleural EMPYEMA = pus in pleural sac, dt bact, fungi, amebas, pneumo, chest wound/surgery, lung abscess, ruptured esophagus, infx enters via blood or other circ or surgery/trauma. ORGS: Strep pneumo, H flu, Staph aureus. S/Sx: same as pneumonia, if severe may become dehydrated, cough up blood or green/brown sputum, fever as high as 105 or fall into coma.

ARDS = sudden, life-threatening lung failure from inflamed alveoli that fill with fluid and collapse, requires advanced medical care immediately, mortality rate is 35-50%, death from complications of mechanical ventilation. Survivors take 6-12 months to regain normal lung function. Any lung injury can precipitate this. RISKS: serious infx anywhere, primary bacterial or viral pneumonia, inhalants (smoking, chems), drug OD, pancreatitis, trauma, head injury, cadiopulmonary bypass surgery, aspiration of gastric contents, shock, burns, multi-tranfusions ABO, uremia, emboli of fat, air, amniotic fluid, NEAR DROWNING. S/Sx: develops in 24-48 hours after injury/illness, dyspnea, tachypnea, severe hypoxia, cyanosis, pulmonary hypertension, abnormal deposits in lungs. PE: labored breathing, tachypnea, cyanosis, moist skin, hyperventilation, increased work of breathing, lethargy followed by obtundation, tachycardia, scattered crackles, agitation. DX: chest x-ray (fluid in avleoi of both lungs), abnormal arterial blood gasses, abnormally low blood pressure in pulmonary arteries. COMPLICATIONS: multi-organ failure, irreversible pulmonary fibrosis. PROGNOSIS: mortality rate averages 60% (from same notes as conflicting stat above), non-survivors die from sepsis ormulti-organ failure, survivors may have no loss of fx or may have pulmonary fibrosis and restrictive lung dz

ATELECTASIS with 4 causes: 1) intrinsic obstruction (mucus, foreign body, tumor, aneurism, kink, bronchospasm, inflam, CF) 2) extreinsic osbstruction (enlarged or aberrant vessel or LN's, masses in chest, pneumothorax or pleural effusion esp after surgery) 3) compressed lung tissue dt chest wall, pleural or intraparenchymal masses, loculated collection of pleural fluid. 4) alveoli may incompletely expand and eventually collapse (opiates, sedatives, anesthesia, immobility, neuromuscular dz, pain from upper abdom surgery, abdom distention, chest wall pain)

THROMBO EMBOLISM = lodging of blood clot in pulmonary artery cause obstruction of blood supply to lung parenchyma => 10% go to pulmonary infarctions. Usu from clot formed in leg or pelvis. Very common in hospital pt, abdom or lower extremity surgery, trauma, hip fx, cast on leg, prolonged immobilization, also w/ malignancy, CHF, abnormal clotting, obesity, pregnancy (amniotic risk)

SARCOIDOSIS = chronic dz affecting multiple systems, noncaseating granulomas @ hilum of lung, more in young female Africans, Scandinavians, Germans, Irish & Puerto Ricans, most in ages 20-40. Lungs usu first to be affected and in 9/10 of cases. also possible: SKIN PLAQUES AND LESIONS: erythema nodosum on legs, lupus pernio ("sarcoids", violaceious lesions on face/extremities) 20-30% EYES involved, uveitis, blurry vision, redness, tearing, photophobia,karatitis sicca, cataracts, glaucoma, blindness, also affects brain, nerves, heart, liver, endocrine. Granulomas may make excess doses of vitamin D !! ->high calcium levels in blood, urine, often kidney stones, may affect CRANIAL NERVE VII cusing bell's palsy, meningitis, neuropathies, also MUSCULOSKELETAL complaints: mysotisi, polyarthritis, spondyloarthorpathy (assoc with positive HLA-B27, back pain or sacroiliac pain),bony lesions, HEAD, NECK AND UPPER RESP: dry cough, rales, tonsilitis, parotitis, epiglottiits, hoarseness, stridor, cough, nasal involvement (damage to septum and tubinates) CARDIAC: cor pulmonale most common, also complete heart block, ventricular tachycardia (most common arrhythmia) bundle branch block (BBB), ventricular aneurism,myocarditis, pericarditis, CHF. MORE: painless LN's, splenomegaly in 10%, hepatomegaly in 25%, nepholithiasis. COURSE: variable, often self resolving, may see permanent lung damage, 5% fatality. DX: biopsy during bronchoscopy of granuloma (look also for fungal infx or lymphoma), chest x-ray positive in 90%, plumonary function tests, may have low WBC's. TX: ?.

HISTOPLASMOSIS = another fungal infection that is rare in healthy people and is regional in incidence. when disseminated can be fatal. Infx is common dz is rare. 80% of people in endemic region have positive skin test: Ohio and Mississippi river valleys. Lives in soil rich with bat or bird droppings. S/Sx: appear 5-18 (usu 10) days after exposure, MILD infx: tired, fever, chills, chest pain, dry cough, CHRONIC: like TB, mostly in pts with other lung dz, progresses over years and can scare lungs, also EYES, SKIN: erythema multiforme, arthritis and erythema nodosum in 5-6%, rarely rales or wheezes, 10% asymptomatic pleural effusions, 5% pericarditis, hepatosplenomegaly occ present. CHRONIC PROGRESSIVE DISSEMINATED: see oropharyngeal ulcers on buccal mucosa, tongue, gingiva, larynx. DIAGNOSIS: culture sputum, positive skin test for outbreaks. PROGNOSIS: for acute, good, for chronic expect relapses, if untreated and subacute can progressively disseminate and result in death in 2-24 months.

locular = Having, formed of, or divided into small cavities or compartments.

obtundation = mental blunting with mild to moderate reduction in alertness and a diminished sensation of pain

PLEURAL EFFUSION = excess fluid in pleural space, 10-20ml, 1ml usu present dt balance of hydrostatic and oncotic forces in visceral and parietal pleural vessels. SXS: DYSPNEA usudt distortion of diaphragm and chest wall during respiration, also sometimes mild nonprod cough or chest pain.

PNEUMOTHORAX = free air or gas in pleural cavity btw visceral and parietal pleura, entering through perforation in chest wall and resulting in collapse of lung on affected side, 2 types: spontaneous (emphysema, interstitional lung dz, DF, asthma, abscess, TB, malig) and traumatic (chest trauma, lung biopsy, mechanical ventilation, esophageal perforation). S/SX: sudden sharp pain (90%), dyspnea (80%), occ dry hacking cough at onset referred pain to shoulder, abdomen, often no abn signs. PE: decreased vocal fremitus, decreased BS, increased tympany on percussion if a lot of ain in pleural space, tracheal deviation. Xray: see air btw lung and pleura, mdeiastinal shift. COURSE: 50% return within 2 years if not surgically repaired, idiopathic type low mortality, underlying dz 15 % mort. TALL, THIN people have higher risk.

SLEEP APNEA = periodic cessation of breathing during sleep for 10 sec or more, up to 300 times/night, EPIDEMIC and often misdiagnosed, easier DX with sleep partner who can report. EVALUATION by polysomnography, measures arterial O2, rib motion, ocular motion EGG while sleeping. ETIO: blockage of airways dt bone structure, swelling. ALSO: obesity (70% with OSA are obese), neck circumference, use of alcohol or medications, sleeping on your back, using one or more pillows, smoking. RISKS: snoring, poor sleep habits, endocrine disorders: hypothyroidism and acromegaly, aging in people over 30, males 2-3x more than female, family hx, black, Hispanic, Pacific islander, weakened muscle tone in tongue and throat, conditions and cause head and face abnormalities (Marfan's, Down syndrome), MENOPAUSE. S/SX: loud snoring and excessive daytime sleepiness, tossing and turning and night, choking, sweating, chest pain, waking unrefreshed, memory and concentration problems, irritable and tired, personality changes, mornign headaches, hypertension, GERD, leg swelling, low libido. Elevated BP does not respond to BP meds. Elevated hemoatocrit, be esp suspicious if menstruating female. Polycythemia--rashes, redness below knees, due to increased viscousity of blood. TX: CPAP machine, positive pressure O2, sleep on back, must adjust to machine but dramatically increases quality of life.