Etiology
Most common viral cause of bronchiolitis
RSV
Barking cough, hoarseness, inspiratory stridor
Croup (laryngotracheitis)
Disease with peripheral airway narrowing, mucus plugging the bronchioles, and alveolar air trapping
bronchiolitis
Preferred test for RSV
RSV PCR
Tx of bronchiolitis
~supportive care~
Tylenol/Ibuprofen > 6mo old, hydration, oxygen (if severe --> high flow nasal cannula)
Which age group has the highest risk for severe RSV disease
Infants < 6 months
Adults > 65
Note: leading cause of hospitalization in kids < 1 year
Paroxysmal coughing fits, high-pitched deep inspiration, post cough vomiting
Pertussis (whooping cough)
What age range is croup most common in?
6 mo - 3 years
note: uncommon after 6 years
What test is used to diagnose pertussis
Nasopharyngeal PCR + culture
Note: culture is the gold standard, CDC recommends both pcr and culture
First-line treatment for pertussis
macrolides (azithromycin, erythromycin, clarithromycin)
note: bactrim (TMP-SMX) can be an alternative if intolerant and age > 2 mo
Describe the 3 phases of pertussis
Catarrhal phase - "insidious onset," most contagious, 1-2 weeks, URI symptoms
Paroxysmal phase - bursts of rapid, consecutive coughs followed by deep, high-pitched inspiration (whoop), 2-8 weeks
Convalescent phase - slow resolution of cough, "100 day cough"
Infant < 2 years with wintertime illness, wheezing, tachypnea, crackles, and retractions
Disease where microorganism attaches to ciliated resp epithelium and releases toxins. These cause ciliary paralysis, impaired mucus clearance, inflammation, cough, and LYMPHOCYTOSIS
Pertussis
If you get neck x-rays of a patient with croup, what sign will you see and what does it mean?
Steeple sign - subglottic narrowing of trachea
First line treatment for croup
Dexamethasone and racemic epinephrine
note: Dex reduces risk of returning to ER
What is the one UPPER respiratory tract infection we learned about, and what organism causes it?
Croup (laryngotracheitis)
Parainfluenza virus type 1
Generally appears well, forced expiratory wheezing, rhonchi improving with cough, nasal congestion, chest pain with cough, headache
Bronchitis
What is the pathophysiology of popcorn lung?
Its bronchiolitis obliterans
Toxins are inhaled (like diacetyl - a compound used for flavoring in vapes) and vaporized, so they're small enough to get all the way to the bronchioles, attack the epithelial layer, causing inflammation/abnormal repair/scarring, leading to PERMANENT narrowing/obstruction
note: in adults only + develops over weeks - months
When are 3 circumstances a CXR is considered for bronchiolitis and what will it show?
Pt has severe disease, ICU admission, atypical presentation, concern for bacterial infection, febrile neonate, hospital infection control decisions
increased bilateral PERIBRANCHIAL THICKENING, hyperinflation, patchy atelectasis
note: CT scan shows "tree-in-bud pattern" = nodular infiltration
What are the antivirals for RSV, COVID-19, and Influenza
Ribavirin, Remdesivir, and Oseltamivir
What are the 4 types of patients at the highest risk for severe RSV complications?
Premature infants, chronic lung disease, congenital heart disease, and immunocompromised
6 month old with URI symptoms that progressed into respiratory distress with nasal flaring, cyanosis, poor feeding, and prolonged expiration
SEVERE bronchiolitis
What is the Westley Score used for and what score calls for admission?
What are 3 indications for a CXR in adult acute bronchitis and what is one complication that might show up on CXR?
Febrile (>100.4), HR > 100, RR > 22, O2 < 95%, rales, egophony, tactile fremitus, mental status changes, moderate dyspnea, hemoptysis, or older/immunocomp pts
BRONCHIECTASIS - bronchial tubes are permanently damaged, widened, and thickened
When should an infant receive RSV monoclonal antibody prophylaxis and whats it called?
Nirsevimab - given when maternal RSV vaccination was not given, unknown, or occurred < 14 days before delivery