acidosis vs alkalosis respiratory rate Correct Answer acidosis
stimulates respiration to blow off excess CO2, alkalosis
depresses respiration to retain CO2
active TB dx
3 tests Correct Answer acid-fast smear and sputum culture x3
days: TB r/o after 3 (-) smears. AFB cultures gold standard.
early AM gastric secimens if unable to give sputum
CXR: indicated to exclude active TB (new + PPD), used as
yearly screening in pts w/ known + PPD or r/o active TB. may
be normal or show variety of patterns:
-reactivation: apical (upper lobe) fibrocavitary disease
-primary TB: middle/lower lobe consolidation
-miliary TB: CXR shows small *millet-seed* like nodular
lesions (2-4mm)
-TB pleurisy: pleural effusion caused by TB infection
-granuloma: residual evidence of healed primary TB. *gohns
complex* -- calcified primary focus + lymph node. *rankes
complex* -- healed fibrocalcific gohn complex seen on CXR
interferon gamma release assay: blood test w/ improved
specificity, no reader bias, no booster phenomenon and not
affected by prior BCG vaccination. ex: *quantiferon-TB gold
assay*
active TB treatment Correct Answer 4 drug tx x2mo, total tx
duration 6mo (or 3mo after - sputum culture). if culture shows
,sensitivity to INH and RIF, stop ETH or STM. PZA usually
discontinues after 2mo regardless of specificity
RIPE: rifampin, isoniazid, pyrazinamide,
ethambutol/streptomycin
not infectious 2wks after initiation of therapy
INH prophylaxis given to children <4y/o w/ exposure to
contacts w/ active disease
acute bronchiolitis dx Correct Answer CXR: hyperinflation,
peribronchial cuffing, nasal washings using monoclonal Ab test
pulse ox best predictor of disease in children <96% will be
admitted
acute bronchiolitis pathophysiology
pathophys, pathogens, RFs, complications Correct Answer
lower respiratory tract infection of the small airways -->
proliferation/necrosis of the bronchiolar epithelium produces
obstruction from the sloughed epithelium, increased mucus
plugging, and submucosal edema leading to peripheral airway
narrowing and variable obstruction
respiratory syncytial virus (RSV) MC cause (part of
paramyxovirus family). other: adenovirus, influenza,
mycoplasma, pneumonia, chlamydia trachomatis
,RFs: infants <2y/o MC affected, <6mo, exposure to cigarettes,
lack of breastfeeding, premature (<37wks gestation) and
crowded conditions. MC in the fall and spring
complication: otitis media w/ s. pneumo MC acute sx (asthma
later in life)
acute bronchiolitis prevention Correct Answer palivizumab
prophylaxis may be used in high risk groups, hand washing
(transmitted by direct contact w/ secretions and self-inoculation
by contaminated hands)
acute bronchiolitis sx Correct Answer fever, URI sx 1-2 days
--> respiratory distress (wheezing, tachypnea, nasal flaring,
cyanosis, retractions, rales)
acute bronchiolitis tx Correct Answer supportive: humidified
O2 mainstay, delivered by mask, tent, or hood. IV fluids,
acetaminophen/ibuprofen for fever; mechanical ventilation for
severe
limited tx: beta agonists, nebulizer racemic epi if albuterol not
effective, corticosteroids (not indicated unless history of
underlying reactive airway disease)
ribavirin administered if severe lung disease or heart disease in
immunocompromised pts
acute bronchitis dx Correct Answer clinical, CXR usually
normal or nonspecific
, acute bronchitis pathophysiology Correct Answer
inflammation of the trachea/bronchi (conducting airways), often
follows URI
MC caused by viruses: adenovirus, parainfluenza, influenza,
coronavirus, coxsackie, rhinovirus, respiratory syncytial virus
bacterial: s. pneumo, h. flu, m. catarrhalis, mycoplasma
acute bronchitis sx Correct Answer hallamark is *cough* (+
productive, last 1-3wks). sx similar to pneumonia
acute bronchitis tx Correct Answer symptomatic tx of choice:
fluids, rest, bronchodilators, antitussives only in adults
abx have no benefit in healthy pts, may benefit elderly, COPD,
immunocompromised or pts not responsive to conservative tx,
cough >7-10 days
acute epiglottis (supraglottitis) dx
2 tests Correct Answer laryngoscopy definitive dx: direct
visualization but may provoke spasm. *cherry red epiglottis* w/
swelling
lateral cervical radiograph: *thumbprint sign*. swollen, enlarged
epiglottis
dont attempt to visualize epiglottis w/ tongue depressor in
children