asthma and other respiratory disorders

croup

epiglottitis

bacterial tracheitis

laryngomalacia

vocal cord paralysis

foreign body aspiration

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Type of Noise	Suggests Obstruction
Inspiratory stridor	Supraglottic or glottic (upper airway)
Biphasic stridor	Fixed lesion at the glottis or subglottis
Expiratory stridor/wheeze	Intrathoracic trachea or bronchi (lower airway)

Sound	Think	Location	Examples
Inspiratory stridor	Upper airway obstruction	Larynx/trachea	Croup, epiglottitis, foreign body
Expiratory wheezing	Lower airway obstruction	Bronchi/bronchioles	Asthma, bronchiolitis (RSV)
Biphasic stridor	Fixed/central airway obstruction	Subglottis/trachea	Vascular ring, subglottic stenosis

differential diagnosis for stridor

- Asthma

-Bronchiolitis (RSV)

- Viral-induced wheeze

- Allergic reaction/anaphylaxis

- Foreign body aspiration

- Tracheomalacia

differential diagnosis for wheezing

Choanal stenosis/atresia

-congenital problem in the neonatal period, relatively rare

-obstruction off nasal passages----> Cyanosis that WORSENS with feeding and IMPROVES with crying

• Inability to easily pass a small catheter through the nostrils should raise the suspicion of choanal atresia.

• The diagnosis is confirmed by CT scan and by inspecting the area directly with a flexible nasopharyngoscope.

• An oral airway may be useful in the short term, but the definitive treatment is surgery

how do you diagnose choanal atresia?

Croup (laryngotracheobronchitis)

Parainfluenza virus (most common),

6mo’s-3yrs

Inspiratory stridor

Barking or brassy harsh cough

Hoarseness,

worst at night, Low grade fever

CROUP: (laryngotracheobronchitis)

steeple sign due to subglottic narrowing on CXR

diagnostic finding of ?

• Mild: dexamethasone PO.

• Moderate-severe: nebulized racemic epinephrine + dexamethasone.

• Oxygen if hypoxic.

treatment of croup

HiB »

GAS, staph a.

—

note: 2–7 yr (less common after Hib vaccine)

most common agents of epiglottitis

epiglottitis

Prefer sitting head held forward, mouth open, jaw thrust forward (sniffing position)

Muffled voice, sore throat, fever, drooling/secretions, dyspnea or stridor

epiglottis:

thickened and bulging epiglottis (thumb print sign)

CXR finding of?

Secure airway first (ET tube),

then IV ceftriaxone or cefotaxime ± vancomycin

• can be extubated 48-72 hours

management of epiglottitis

Laryngomalacia

_{Floppy/immature supraglottic structures collapse during inspiration}

_{dx: Flexible laryngoscopy}

Infant presents within the first few weeks of life with:

• inspiratory stridor

• WORSE with feeding, crying, or lying SUPINE

• and improves when PRONE/upright.

resolve on own usually by 20 months (12-24mo’s)

severe cases → supraglottoplasty

management of laryngomalacia

bacterial tracheitis

-staph aureus

preschool/school age children

Superinfection of the trachea that may follow viral croup and most commonly caused by S. aureus

High fever, toxic appearance, stridor, thick purulent secretions, poor response to racemic epinephrine

Irregular tracheal narrowing, subglottic edema in imagining

Toxic appearing

Spasmodic croup usually at night

inspiratory stridor

thick purulent secretions

signs and symptoms of bacterial tracheitis

subglottic stenosis

Narrowing of the space below the glottis and above the first tracheal ring;

involves narrowing of the cricoid, the only complete cartilage ring in the airway

often occurs after long periods of intubation and ventilation for respiratory problems

cause of acquired subglottic stenosis

Recurring croup

Respiratory distress

Noisy breathing

Inability to breathe without tracheostomy

signs and symptoms of subglottic stenosis

damage to recurrent laryngeal nerve (CN X) or the vagus nerve itself.

Category	Associated Conditions	Board Pearls
Birth trauma	Difficult vaginal delivery, forceps delivery, shoulder dystocia	Most common cause of unilateral VCP in neonates.
Congenital CNS abnormalities	Arnold-Chiari II malformation, hydrocephalus, meningomyelocele	⭐ Chiari II is the most tested congenital association, especially with bilateral VCP.
Cardiac surgery	PDA ligation, aortic arch repair, congenital heart surgery	Injury to the left recurrent laryngeal nerve is common because it loops under the aortic arch.
Neck/thoracic surgery	Thyroid surgery, tracheoesophageal fistula repair, ECMO cannulation	Surgical nerve injury is a common acquired cause.
Neurologic disorders	Brainstem tumors, cerebral palsy, hypoxic-ischemic injury, cranial neuropathies	Consider when VCP occurs with other neurologic deficits.
Trauma	Intubation trauma, neck trauma	May cause temporary or permanent paralysis.
Mass lesions	Mediastinal tumors, vascular rings, enlarged lymph nodes	Compression of the recurrent laryngeal nerve.
Idiopathic	No identifiable cause	Accounts for a significant proportion of pediatric cases.

conditions associated with vocal cord paralysis

low dose ICS

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Medication	Typical Low Daily Dose*	Notes
Fluticasone propionate (Flovent HFA)	88 mcg/day (44 mcg, 1 puff BID) to 176 mcg/day	Very commonly used in children
Budesonide (Pulmicort Flexhaler)	180–360 mcg/day	Dry powder inhaler (older children)
Budesonide nebulizer (Pulmicort Respules)	0.5 mg/day	Preferred ICS for infants and young children who need nebulizer therapy
Beclomethasone (QVAR RediHaler)	80–160 mcg/day	Breath-actuated inhaler
Mometasone (Asmanex)	110 mcg once daily (age-dependent)	Once-daily option in many patients
Ciclesonide (Alvesco)	80 mcg/day	Lower oropharyngeal deposition due to prodrug activation

Step	Treatment
Step 1 (Intermittent)	Albuterol (SABA) as needed
Step 2 (Mild persistent)	⭐ Low-dose ICS daily + albuterol PRN
Step 3	Low-dose ICS/LABA or medium-dose ICS
Step 4	Medium-dose ICS/LABA
Step 5–6	High-dose ICS/LABA ± biologic therapy ± oral corticosteroids (specialist management)

treatment of step 2 persistent asthma

Low dose ICS + LABA

or

medium dose ICS

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Regimen	Examples	When Used	Board Pearl
Low-dose ICS + LABA	Fluticasone/salmeterol (Advair), Budesonide/formoterol (Symbicort), Mometasone/formoterol (Dulera)	Preferred Step 3 option for many children ≥5–6 years and adolescents	⭐ Preferred over simply increasing the ICS dose in many current guidelines.
Medium-dose ICS	Increase fluticasone, budesonide, beclomethasone, etc., to the medium-dose range	Alternative if LABA cannot be used or in younger children	Common alternative, especially in younger children.

Age	Preferred Step 3
0–4 years	⭐ Increase to medium-dose ICS (LABAs are generally not first-line in this age group)
5–11 years	Low-dose ICS + LABA or medium-dose ICS
≥12 years	⭐ Low-dose ICS + LABA is generally preferred; SMART therapy may be appropriate for some patients using an ICS-formoterol inhaler

Medication	ICS	LABA
Advair	Fluticasone	Salmeterol
Symbicort	Budesonide	Formoterol
Dulera	Mometasone	Formoterol
Breo Ellipta	Fluticasone furoate	Vilanterol (typically for older adolescents/adults, not commonly used in younger children)

treatment of step 3 persistent asthma

medium dose ICS + LABA

treatment of step 4 persistent asthma

high dose ICS + LABA

treatment of stepp 5 persistent asthma

high dose IC + LABA + oral corticosteroid

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Therapy	Examples	Purpose
High-dose ICS	High-dose fluticasone, budesonide, beclomethasone	Maximize anti-inflammatory effect
LABA	Salmeterol or formoterol (always combined with an ICS)	Long-acting bronchodilation
Oral corticosteroid	Prednisone or prednisolone	Reserved for severe, refractory asthma after specialist evaluation
Biologic therapy	Omalizumab, Mepolizumab, Benralizumab, Dupilumab (depending on age and asthma phenotype)	Preferred add-on for many eligible patients to reduce exacerbations and minimize steroid exposure

Step	Treatment
Step 1	Albuterol as needed
Step 2	Low-dose ICS
Step 3	Low-dose ICS + LABA or medium-dose ICS
Step 4	Medium-dose ICS + LABA
Step 5	High-dose ICS + LABA ± biologic (specialist referral)
Step 6	High-dose ICS + LABA + consider maintenance oral corticosteroids if still uncontrolled

treatment of step 6 persistent asthma

intermittent asthma

Symptoms less than 2 times/week and <2 nighttime symptoms/month

Tx with SABA

mild persistent asthma

Symptoms: >2x/wk but <1x/d

Night Sxs: >2x/mo

FEV: >80% prediction

Tx: *Low-dose ICS* > Cromolyn, leukotriene (S/E: ↑ mucous production)

moderate persistent asthma

FEV1/PEF 60-80%, daily symptoms. SABA, daily moderate dose ICS, or low dose ICS and LABA

severe persistent asthma

FEV1/PEF <60%, symptoms most of day. SABA, high dose ICS, LABA, oral steroid daily

-nightly wakenings

Ongoing self-management, detecting early decline before symptoms

indication to measure peak expiratory flow

peak expiratory flow meter

Device measuring maximum airflow during exhalation.

spirometry

-gold standard for diagnosis of asthma and assessing severity

normal ~0.75-0.80 in adults,

≥0.85 in children

what is a normal FEV1/FVC ratio

↑ FEV₁ ≥ 12% and ≥ 200 mL = significant reversibility

post bronchodilator response FEV1 value supporting asthma diagnosis

FVC

total air exhaled after full inspiration

Asthma episode not controlled in 30-60 min with standard treatment

Hypoxemia, hypercarbia, secondary respiratory failure

define status astmaticus

O2

SABA

anticholinergic

systemic corticosteroidsd

management of status asthmaticus

	Tracheomalacia
Classic presentation	Infant with noisy breathing + barking/brassy cough
Breath sound	Expiratory stridor/wheeze
Worse with	Crying, coughing, feeding, respiratory infections
Why expiration?	Intrathoracic pressure rises → weak trachea collapses
Associated with	Tracheoesophageal fistula/esophageal atresia, vascular compression, prolonged intubation
Diagnosis	Dynamic bronchoscopy = gold standard
Treatment	Most cases → observation/supportive care
Severe disease	CPAP may splint airway open; occasionally surgery
Prognosis	Congenital cases often improve as cartilage strengthens

congenital Floppy tracheal cartilage → airway collapse during expiration

newborn screening (IRT)

• IRT = Immunoreactive Trypsinogen

Sweat chloride test (>60 mmol/L),

CFTR genetic testing,

diagnostic approach to cystic fibrosis

👶 Meconium ileus

🫁 Recurrent infections → bronchiectasis → respiratory failure
🥞 Pancreatic insufficiency → steatorrhea + ↓ A,D,E,K
🍬 CF-related diabetes
🟢 Biliary cirrhosis
👃 Nasal polyps/chronic sinusitis
♂ Absent vas deferens → infertility
🧂 Salt loss → hypochloremic metabolic alkalosis

sequelae of cystic fibrosis

Expiratory stridor, barking cough, worse with crying/URI, recurrent respiratory infections

signs and symptoms of tracheomalacia

Mild: observation (improves by 18-24 mo);

Severe: CPAP, surgical aortopexy/tracheal stenting

management of tracheomalacia

bronchopulmonary dysplasia

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_Prevention:

_{• Antenatal steroids • Surfactant therapy • Gentle ventilation strategies}

 

 _Treatment:

_{• Oxygen supplementation • Diuretics (furosemide) if pulmonary edema • Nutrition optimization • Bronchodilators if reactive airway symptoms}

Chronic lung disease in preterm infants (<32 wks) with prolonged oxygen/mechanical ventilation → alveolar simplification & fibrosis

Oxygen dependence >28 day

 Chest X-ray: hazy opacities, hyperinflation

clinical dx

tracheoesophageal fistula

associated with VACTERL

Failed separation of trachea & esophagus (most often esophageal atresia + distal TEF)

tracheoesophageal fistula

Polyhydramnios prenatally;

newborn with choking, coughing, cyanosis, drooling during feeds; inability to pass NG tube

AR defect in dynein arms → impaired ciliary motility → defective mucociliary clearance

etiologgy of primary ciliary dyskinesia

Neonatal respiratory distress, chronic sinusitis/otitis, recurrent pneumonia, situs inversus (Kartagener: PCD + situs inversus + chronic sinusitis), infertility

signs of primary ciliary dyskinesia

Primary Ciliary Dyskinesia

-Inherited abnormality of ultrastructure of the cilia

-Caused by dynein arm defect

-Pt's present w/ recurrent infections, bronchiectasis, Kartagener syndrome

Dx: Electron microscopy of respiratory cilia

Tx: Preventative abx, surveillance cultures, sinus surgeries

pectus excavatum

Posterior depression of sternum & costal cartilages

pectus carinatum

Anterior protrusion of sternum & costal cartilages

-often asymptomatic

Retropharyngeal abscess

Deep neck-space infection;

tx with Abx and surgical drainage

Fever + drooling + dysphagia  + neck stiffness/limited ROM + muffled voice

caused by: Staph, Strep, anaerobes; typically <5 yr

contrast CT neck → retropharyngeal fluid collection/rim enhancement.

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_{note: Lateral neck X-ray → widened prevertebral space}

1st line imaging for suspected Retropharyngeal abscess

peritonsillar abscess

_{Infection between tonsillar capsule and pharyngeal muscles;}

 _{usually after tonsillitis; GAS + anaerobes}

_{tx with abx and surgical drainage}

_{*can spread to retro structures}

severe unilateral throat pain

+ hot-potato voice

+ TRISMUS

+ drooling

+uvula dev’s AWAY

foriegn body aspiration

 Sudden choking/coughing.

Upper airway → stridor.

Bronchial → unilateral wheeze/dec’d breath sounds

RIGHT BRONCHIAL MAINSTEM

most common location of foriegn body aspiration

CXR first ± inspiratory/expiratory or decubitus views

→ unilateral air trapping/hyperinflation or atelectasis.

first imaging for foriegn body aspiration

rigid bronchoscopy = diagnosis + treatment

gold standard for foriegn body aspiration

decreases due to hypervent.

ABG PaCO2 in an acute asthma attack

PaCO2 will be normal in fatigue

and will be increased in resp failure

how do you know if asthma is getting worst even though patient doesnt seem to be stuggling (silent chest)

Vascular ring

= congenital aortic arch anomaly that surrounds/compresses the trachea and/or esophagus.

dx w/ CT // tx: surgical correction

biphasic stridor that worsens with feeding or crying

improves with neck extension

worst in prone

Feature	B. PERTUSSIS (WHOOPING COUGH)
Organism	Gram-negative coccobacillus, aerobic
Transmission	Respiratory droplets
Major virulence factor	Pertussis toxin → ↑ cAMP
Mechanism	ADP-ribosylates Gi → inhibits Gi → ↑ adenylate cyclase → ↑ cAMP
Classic CBC	⭐ Lymphocytosis
Classic symptom	Paroxysmal coughing → inspiratory “whoop” → post-tussive vomiting
Infants	May have apnea/cyanosis instead of classic whoop
Diagnosis	Nasopharyngeal PCR
Treatment	Macrolide (usually azithromycin)
Prevention	DTaP/Tdap
Close contacts	Macrolide prophylaxis, regardless of vaccination status

Child with weeks of severe coughing fits + inspiratory whoop + vomiting after coughing + lymphocytosis =

Bordetella pertussis

Catarrhal → Paroxysmal → Convalescent

• Catarrhal: runny nose, low fever, mild cough → MOST contagious

• Paroxysmal: coughing fits + whoop + post-tussive vomiting

• Convalescent: cough gradually improves but may persist for weeks

Macrolides (azithromycin)

B. pertussis

infant with severe cooughing fits followed by vomitting and spells of apnea is tx with?:

• Group B Strep (Streptococcus agalactiae)

• E. coli

What are the most common causes of community-acquired pneumonia in neonates?

virus

What is the most common cause of community-acquired pneumonia in infants <1 year?

• Viruses

  • Most common cause of pneumonia overall in this age group

  • Respiratory syncytial virus, influenza A and B, human metapneumovirus, adenoviruses, parainfluenza viruses, enterovirus, coronaviruses

• Bacteria

  • Streptococcus pneumoniae: most common cause of typical bacterial pneumonia in all patients beyond the first few weeks after birth

  • Staphylococcus aureus: may occur as a secondary infection following influenza* pneumonia

  • Streptococcus pyogenes: may occur as a secondary infection following varicella infection

  • Atypical pathogens: Mycoplasma pneumoniae, Chlamydia pneumoniae

What is the most common cause of pneumonia overall in children 1–4 years?

• Bacteria

  • S. pneumoniae: most common cause of typical bacterial pneumonia in this age group

  • M. pneumoniae: most common cause of bacterial pneumonia overall in this age group

  • C. pneumoniae

What are the common causes of community-acquired pneumonia in children ≥ 5 years of age?

pneumo

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note:

Typical bacterial:
🔥 Higher fever + focal crackles + lobar consolidation

Viral/atypical:
🌬 More diffuse findings + bilateral/interstitial infiltrates

Most important physical sign in kids: Tachypnea is a particularly useful clue for pneumonia.

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Finding	What you'll see
Symptoms	⭐ Fever + cough + tachypnea
Breathing	Tachypnea, dyspnea, retractions, nasal flaring
Infant clues	Poor feeding, irritability, lethargy; may have grunting
Auscultation	⭐ Crackles (rales), decreased breath sounds; possible bronchial breath sounds
Percussion	Dullness over consolidated lung
Oxygen	May have hypoxemia/cyanosis if severe
CXR – bacterial	⭐ Focal/lobar consolidation ± air bronchograms
CXR – viral/atypical	Diffuse/interstitial infiltrates, often bilateral

Fever + cough + tachypnea + crackles → think

early onset neonate pneumo (48 hours to 6 days of age)

Transmission

• Intrauterine aspiration of amniotic fluid

• Transplacental transmission

• Aspiration of infected amniotic fluid during or after birth

Risk Factors

• Prematurity and low birth weight (typically <2500 g [5 lb 8 oz])

• Intraamniotic infection

• Premature or prolonged rupture of membranes

• Maternal Group B Streptococcus colonization

• Maternal intrapartum fever

Most Common Bacterial Pathogens

• Group B Streptococcus

• Escherichia coli

Initial Empiric Therapy: Ampicillin + gentamicin

broad gram + and - coverage

early onset neonate pneumo (48 hours to 6 days of age)

is treated with?

late onsent neonate pneumo (>7 days of age)

Transmission

• Maternal vertical transmission in the community

• OR horizontal transmission if still hospitalized (ie, ventilator-associated)

Risk Factors

• Prematurity and low birth weight (typically <2500 g [5 lb 8 oz])

• Invasive mechanical ventilation

• Anatomic anomalies (eg, choanal atresia, tracheoesophageal fistula)

• Prolonged hospitalization

• Underlying severe pulmonary disease

Most Common Bacterial Pathogens

• Group B Streptococcus

• Escherichia coli

• Staphylococcus aureus

• Klebsiella pneumoniae

• Coagulase-negative staphylococci

Initial Empiric Therapy

• Ampicillin OR vancomycin

PLUS

• Aminoglycoside (typically gentamicin) OR

• Extended-spectrum cephalosporin

late onsent neonate pneumo (>7 days of age)

is treated with?

typical pneumo strep pneumo

RX

• Amoxicillin**

• Levaquin/levofloxacin OR Clindamycin (if penicillin allergy)

• Linezolid (if high rates of resistance)

• Augmentin/amoxicillin-clavulanate (if aged 6 months to 5 years, use others if ≥ 5 years)

5yo male: high fever, productive cough with green sputum, crackles, and egophony (EEE —> AAA = +lung console.)

• Child looks relatively well → “walking pneumonia”

Mycoplasma, which usually causes a drier, more gradual “walking pneumonia” presentation.

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> 5-year-old, remember:
S. pneumoniae = most common typical bacterial pneumonia
Mycoplasma = most common bacterial pneumonia overall in older children/school-age kids

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rx:

For atypical pneumonia due to Mycoplasma pneumoniae in a child:

• ⭐ Azithromycin = first-line (macrolide 50S) // Alternative: clarithromycin

• Doxycycline can be used in older children when appropriate.

mycoplasma has NO cell wall so pencillins WONT work !!

10-year-old comes in with:

• Gradual onset over several days

• Low-grade fever

• Dry, nonproductive cough

• Headache, malaise, sore throat

• Lung exam may have diffuse crackles

• CXR → diffuse/interstitial infiltrates rather than focal lobar consolidation

staph a » pseudomonas

Pneumo in a ped with CF is likely?

Mycoplasma Species Pneumonia

Epidemiology

• Respiratory droplet transmission

• Close quarters (military, college dormitories, day care)

• Summer and early fall

Clinical Features

• Insidious onset of headache, malaise, low-grade fever, persistent nonproductive cough

• Macular/vesicular rash

• ± upper respiratory tract symptoms, pharyngitis

Diagnostics

• Hemolytic anemia, normal leukocyte count

• High titers of serum IgM

• Patchy or diffuse interstitial infiltrates on chest x-ray

Treatment

• First-line: macrolides (eg, azithromycin)

• Alternatives: tetracyclines (eg, doxycycline) or fluoroquinolones (eg, levofloxacin)

Bronchiolitis

Pathophysiology

• Viruses infect the terminal bronchiolar epithelial cells, causing direct damage and inflammation in the small bronchi and bronchioles

• Edema, excessive mucus, and sloughed epithelial cells lead to obstruction of small airways and atelectasis

Causes

• Respiratory syncytial virus (most common)

• Parainfluenza virus, Influenza virus, Adenovirus, Coronavirus

Clinical Manifestations

• Generally presents with fever (usually ≤ 38.3°C [100.9°F]), cough, and respiratory distress (eg, increased respiratory rate, retractions, expire. wheezing, crackles)

• Often preceded by a 1–3 day history of upper respiratory tract symptoms (eg, nasal congestion and/or discharge)