Lecture 1: Pulmonology

Question 1

derangements of breathing in pediatrics

Answer 1

• respiratory disease is the most common reason for pediatric hospitalization
• hallmark distinction of airway noise
  
  • upper airway obstruction - stridor
  • lower airway obstruction - wheeze
  • air trapping and prolonged expiratory phase can occur in either upper or lower obstruction

Question 2

nasal obstruction

Answer 2

• Newborns and young infants are obligate nasal breathers
• Significant respiratory distress can occur
• Can also lead to difficulty feeding

Question 3

oxygenation vs. ventilation

Answer 3

• ventilation and oxygenation occur independent from one another
  
  • processes compromise each function differently
  • both may be affected by severe obstruction
• Oxygenation affected first

Question 4

respiratory rate varies with age

Answer 4

• age
  
  • infant
  • 1-3 years
  • 4-6 years
  • 7-14
  • 14-18
• respiratory rate
  
  • 24-38
  • 22-30
  • 20-24
  • 16-24
  • 14-20
• always count respiratory rate over 60 seconds
• *Periodic breathing*

Question 5

respiratory exam

Answer 5

• observe over time since external stimuli may influence the exam
• do not be afraid to palpate and undress patient
• tachypnea is the most sensitive sign of pneumonia in children
• stridor is most commonly inspiratory, monophasic, noise
  
  • Can be inspiratory, expiratory or fixed depending on the cause
• wheezing is continuous sound caused by turbulent flow in narrow airways
  
  • Pitch can identify the part of airway involved
• rales (crackles) are fine, interrupted sounds that suggest pulmonary parenchymal disease
• Rhonchi are coarse, interrupted sounds that suggest large airway disease
• Egophany CAN be used in children who can follow instruction

Question 6

respiratory distress in children

Answer 6

• children mount a progressive effort with worsening compromise
• first, tachypnea
• then, further labored breathing
  
  • retractions
    
    • abdominal (“subcostal”)
    • intercostal
    • supraclavicular
  • nasal flaring
  • grunting
    
    • attempt to maintain area for gas exchange by providing extra end expiratory pressure
• positioning
  
  • upright (gravity aids diaphragmatic contraction)
  • tripodding (allows more efficient scalene and intercostal work)
  • sniffing position (opens upper airway)

Question 7

cyanosis

Answer 7

• Blue discoloration of skin due to hypoxemia
• Central cyanosis occurs first
  
  • Perioral/lips/tongue
  • Trunk
  • Extremities
• Poor prognostic factor for severity of disease
  
  • Usually prompts admission to the hospital

Question 8

plain chest film

Answer 8

• good screening test for parenchymal or pleural disease
• poor test of pulmonary function
• upright film at limit of inspiration is best
  
  • often difficult in small children, may require repeat of film
  • radiography tech often forgets to compensate for child size when determining exposure
• lateral films very useful for evaluation of retrocardiac space

Question 9

arterial blood gas

Answer 9

• useful measure of pulmonary function
• even more useful if serial measurements allow description of trends
• worrying findings include
  
  • rising pCO2 over 45 mmHg (respiratory acidosis)
  • decreasing pO2 less than 85mmHg (hypoxemia)
  • acidemia (uncompensated acidosis)
• Capillary and venous blood gases are easier to obtain, but pO2 is less helpful
• no utility of pO2 in venous blood gases

Question 10

pneumonia

Answer 10

• = Infection of alveolar spaces
• Viruses
• Bacterial pneumonia

Question 11

viral etiologies of PNA

Answer 11

• Respiratory Syncytial Virus (bronchiolitis)
• Rhinovirus (bronchiolitis)
• Human Metapneumovirus (bronchiolitis)
• Influenza Virus
• Parainfluenza Virus
• Adenovirus
• Herpes Simplex Virus
• Varicella Virus

Question 12

bacterial etiologies of PNA

Answer 12

• Neonate 0-2 months
  
  • Group B Strep
  • E. Coli
  • Chlamydia trachomatis
• Infant 2 months to 24 months
  
  • Streptococcus Pneumonae
  • Group A Streptococci, other streptococci
  • Haemophilus Influenza
  • Staphyloccocus
• Toddler/School Age
  
  • Streptococcus Pneumonae
  • Staphylococcus
  • Mycoplasma

Question 13

When to suspect PNA

Answer 13

• History- fever, cough difficulty feeding, fussiness, chest pain
• Physical Exam- TACHYPNEA, fever, rales, wheezes, decreased breath sounds
• Labs
  
  • CBC, blood culture- Leukocytosis, Pathogen capure only 10-12 percent (hospitalized patient)
  • CXR- “gold standard”
  • Rapid Antigen Testing- available for RSV, Influenza, sometimes adenovirus, parainfluenza
  • Titers- Mycoplasma, HSV

Question 14

tachypnea in PNA: definition

Answer 14

• Younger than 2 months: > 60 breaths/min
• Two to 12 months: > 50 breaths/min
• One to 5 years: > 40 breaths/min
• > 5 years: > 20 breaths/min

Question 15

viral PNA tx

Answer 15

• Supportive Care
  
  • Hydration
  • Oxygen
  • Positioning/Nutrition
• Anti-Viral Agents
  
  • Influenza- Tamiflu
  • HSV- Acyclovir for systemic disease
  • Varicella- VZIG prophylaxis for immunocompromised exposure
• Antibiotics

Question 16

Bacterial PNA tx

Answer 16

• Treatment- empiric tx
  
  • Neonate- GNR=> Cephalosporin
    
    • Staph=>Vancomycin
  • Infant- Strep Pneumo=>Ampicillin
  • Children- Strep Pneumo=>Ampicillin
    
    • Mycoplasma=>Azithromycin
    • Staph=> Clindamycin
    • Staph (bad infection) => Vancomycin

Question 17

complications of PNA

Answer 17

• Pleural effusion
• Empyema
• Treatment
  
  • Sometimes still just antibiotics
  • Can require surgical drainage and chest tubes
• Most often Strep pneumo and Staph aureus

Question 18

phase of stridor

Answer 18

• Inspiratory
  
  • Above the thoracic inlet
• Expiratory
  
  • Below the thoracic inlet
• Biphasic
  
  • Fixed lesions

Question 19

stridor ddx

Answer 19

• laryngeal papillomatosis
• laryngeal trauma
• larygomalacia
• viral croup
• epiglottitis
• bacterial tracheitis
• anaphylaxis
• vocal cord paralysis
• vocal cord dysfunction
• foreign body
• subglottic stenosis
• retropharyngeal abscess
• congenital anomalies
  
  • Pierre-Robin sequence
  • neuromuscular disease
  • Hemangioma
  • Vascular rings/slings
  • Tracheal stenosis

Question 20

croup

Answer 20

• respiratory illness (inflammation of larynx and surrounding airways) that manifests in young children with
  
  • hoarse voice
  • dry, barking cough
  • inspiratory stridor
• most commonly viral
  
  • fever and cough
• steeple sign

Question 21

viral croup

Answer 21

• typically 6 years of age and younger
• occurs any time of year
  
  • most commonly late fall and winter
• symptoms typically worse at night
• 2^nd and 3^rd nights usually the worst
• most commonly parainfluenza viruses
• also
  
  • influenza A and B
  • adenovirus
  • respiratory syncytial virus (RSV)
• diagnosis based on clinical findings
• screen all patients with stridor for immunization history, recent choking or foreign body aspiration, food allergies
• plain films only useful if atypical presentation
• pulse oximetry usually normal in viral croup unless a severe case
  
  • if main airway is compromised to the point of hypoxemia, inpatient monitoring is warranted
• visualization of epiglottis not usually indicated unless concern for epiglottitis (drooling, toxic-appearing)

Question 22

treatment of viral croup

Answer 22

• cool mist
  
  • home shower “steam”
  • car ride with windows down
  • cool water humidifiers
• systemic corticosteroids
  
  • onset of action is several hours after dose
  • no demonstrable benefit for more than two daily doses of dexamethasone
• nebulized racemic epinephrine
  
  • benefit is transient
• for severe cases
  
  • endotracheal intubation (avoided if possible)
  • helium-oxygen mixture

Question 23

cystic fibrosis

Answer 23

• defect in the cystic fibrosis transmembrane conductance regulator resulting in a deficiency in chloride ion transport, causing abnormal fluid secretion
• secretions, including mucus, are thick and tenacious
• multi-organ involvement including chronic pulmonary disease and exocrine pancreatic insufficiency
• autosomal recessive
• most prevalent in northern Europeans
  
  • Caucasians 1 in 2,500
  • African-Americans 1 in 17,000
  • Asians 1 in 90,000

Question 24

diagnosis of cystic fibrosis

Answer 24

• newborn genetic screening
• family history
• sweat chloride
  
  • functional test
  • most sensitive
• DNA testing
  
  • less sensitive
  • can only screen for known mutations

Question 25

clinical presentation of cystic fibrosis

Answer 25

• meconium ileus & chronic constipation
• prolonged jaundice (biliary obstruction)
• failure to thrive
• signs of malabsorption
  
  • Pancreatic insufficiency
  • bulky, foul smelling stools
  • greasy or oily stools
• recurrent lung disease
• Tastes “salty”
• Smell of pseudomonas aeruginosa (common pathogen)

Question 26

management of cystic fibrosis

Answer 26

• chronic recurrent and indolent pneumonias
• recurrent infections contribute to airway and lung parenchymal changes
  
  • bronchiectasis
  • asthma

Question 27

diagnosis of cystic fibrosis

Answer 27

• Newborn Screen
• Sweat Chloride testing
• DNA mutation testing
  
  • Tests for most common mutations in CFTR gene

Question 28

treatment of cystic fibrosis

Answer 28

• systemic and inhaled antibiotic therapy
• airway clearance measures, assist patient with decreasing chronic inflammation clearance and prevent chronic infection
  
  • Albuterol
  • Chest physiotherapy
  • Cough Assist
• Nutrition
  
  • pancreatic enzyme replacement

Question 29

obstructive sleep apnea

Answer 29

• spectrum of disorders where obstruction of airflow results in increased respiratory effort and frequent sleep arousal, increased respiratory effort, hypoventilation, and (sometimes) hypoxemia
• may progress on to
  
  • pulmonary hypertension
  • cor pulmonale (right heart changes and ultimately failure)
• sleeping difficulties
  
  • frequent sleep arousals
  • increased sleeptime respiratory effort
  • daytime hypersonmonlence impairing school performance
    
    • less common in children than in adults
  • snoring
    
    • common in pediatric population
    • ~15% of children have habitual snoring on history
• peak incidence age 4-8 years
• History
  
  • Screen for OSA by asking
  • “Does your child snore”
• exam
  
  • “allergic shiners”
  • allergic rhinitis
  • tonsillar and adenoidal hypertrophy
  • hyponasal speech

Question 30

diagnosis of obstructive sleep apnea

Answer 30

• Polysomnography (gold standard)
  
  • monitors oxygenation and ventilation during sleep
  • gas challenges to determine source of apnea
    
    • central vs. obstructive
• also
  
  • lateral neck film to evaluate airway
  • EKG to screen for right ventricular hypertrophy

Question 31

medical managment for temporary relief if sleep study is unremarkable

Answer 31

• medical management for temporary relief if sleep study is unremarkable
  
  • treat allergic rhinitis
  • treat tonsillitis
• surgical management
  
  • tonsillectomy and adenoidectomy
  • palatouvuloplasty (less common)

Question 32

differential diagnosis for wheezing

Answer 32

• bronchiolitis
• pneumonia
• aspiration
• laryngotracheomalacia
• vascular rings
• airway stenosis or Web
• paratracheal adenopathy
• mediastinal mass
• airway foreign body
• BPD/BOOP
• cystic fibrosis
• vocal cord paralysis
• vocal cord dysfunction
• cardiovascular disease (CHF)
• asthma

Question 33

bronchiolitis cause

Answer 33

• most common cause of acute hospital admissions for infants less than 2 years of age during the winter months
• most common cause
  
  • RSV (respiratory syncytial virus)
  • infects about ~1/3 of all children every year
  • immunity is not long-lasting
• other causes
  
  • influenza, parainfluenza, adenovirus, metapneumovirus
• pathogenesis
  
  • infection and inflammation of the lower airways
  • obstruction results from edema, mucus plugging

Question 34

presentation of bronchiolitis

Answer 34

• begins much like a typical upper respiratory infection
  
  • fever
  • rhinorrhea
  • cough
• Often progressing to lower airway disease
  
  • lower airway secretions => wheezing, rales, coarse breath sounds, worsening cough
  • tachypnea

Question 35

diagnosis of bronchiolitis

Answer 35

• RSV and influenza enzyme immunoassay
  
  • may be useful for cohorting if performed rapidly
• CXR - hyperinflation, atelectasis, multifocal (and often shifting) infiltrates
• CBC - commonly normal, may show mild lymphocytosis consistent with viral illness

Question 36

prevention of bronchiolitis

Answer 36

• Prevention (RSV infects at high rate)
  
  • hand-washing
  • RSV intravenous immune globulin
    
    • palivizumab
    • given to high-risk groups during RSV season each year

Question 37

treating bronchiolitis

Answer 37

• no curative therapy
• supportive care
  
  • oxygen
  • hydration IV fluids/frequent feedings
  • pulmonary toilet (nasal suction, airway clearance, positioning)
• Monitoring
  
  • Assess risk factors (prematurity, chronic lung disease, other underlying pulmonary disease)
  • Apnea risk

Question 38

foreign body presentation

Answer 38

• Obstruction => emergency airway management
• Upper Airway => stridor, drooling
• Lower Airway => wheezing
• Late Presentation => infection, chronic changes, abscess

Question 39

foreign body diagnosis

Answer 39

• History, Physical Exam, CXR to screen
• Gold Standard to rule in or rule out
  
  • Bronchoscopy

Question 40

atopic disease

Answer 40

• Asthma
• Atopic dermatitis (eczema)
• Allergic rhinitis (hay fever)

Question 41

asthma

Answer 41

• asthma is the most common chronic disease of childhood
• despite technologic advances, morbidity has increased
• asthma management has significantly changed over the past decade
• health disparities issues abound in asthma
  
  • African-Americans have a disproportionate amount of disease burden for asthma
  • Certain zip codes are disproportionately affected
• airway hyperresponsiveness to triggers
• disease of excess inflammation, all processes narrow lumen of airway
  
  • inflammatory cell infiltration
  • mucus plugging
  • shedding of airway epithelium
  • mast cell activation
  • bronchoconstriction
• widespread small airway constriction and obstruction impairs air movement, particularly during exhalation
• air trapping evident on exam and chest plain films
• tidal volume reduced as patient must inspire again before exhaling sufficient volume

Question 42

asthma symptoms and signs

Answer 42

• baseline symptoms may be very subtle and clinically hard to diagnose
• mild asthma exacerbation
  
  • cough
  • wheeze
  • exercise intolerance
  • chest congestion
• moderate asthma exacerbation
  
  • dyspnea
  • chest tightness
  • labored breathing
• severe asthma exacerbation
  
  • mental status changes
  • may become paradoxically unlabored when entering respiratory failure
  • cyanosis
  • pulsus paradoxus

Question 43

treatment of asthma

Answer 43

• treatment of acute exacerbation
  
  • systemic corticosteroids
    
    • mainstay of therapy
    • impairs new inflammation
    • inflammation present in airways needs time to “burn out”
  • β₂-agonist (albuterol) – briefly impairs small airway smooth muscle bronchoconstriction
  • ipratropium – inhaled atropine analog (anticholinergic) for large airway dilation
• supportive care (oxygen, hydration)

Question 44

asthma diagnosis

Answer 44

• no specific laboratory findings
• hypoxia with significant airway compromise
  
  • or with significant atelectasis
• chest plain films
  
  • lung hyperinflation
  • atelectasis related to airway plugging
  • peribronchial thickening/cuffing
• pulmonary function testing
  
  • reveal small airway disease
  • methacholine challenge
  • FEV₁ reduced, FEV_25-75 reduced
  • improvement with administration of β-agonist

Question 45

treatment of severe cases of asthma

Answer 45

• parenteral β₂-agonist (terbutaline)
• parenteral epinephrine
• parenteral magnesium
• parenteral theophylline
• mechanical ventilation generally avoided, but if necessary:
  
  • ketamine plus halothane anesthesia with helium-oxygen mixture

Question 46

chronic asthma treatment

Answer 46

• education
• medications
  
  • inhaled corticosteroids
  • long-acting β₂-agonist – associated with increased risk of death
  • leukotriene modifiers
  • mast cell stabilizers (cromolyn)
• environment modification
  
  • Hepa filters
  • smoking
  • dust mite control
  • pets
• reduction of exacerbating factors
  
  • identify triggers and find ways to avoid them
  • treatment of reflux, sinusitis, allergic rhinitis
  • stress reduction
  • influenza vaccine

Question 47

larger treatment goals of asthma

Answer 47

• anti-inflammatory agents
• individualized management plans
• reduction of risks must be ongoing
• early diagnosis and vigilant monitoring with utilization of latest treatment modalities

Question 48

albuterol administration

Answer 48

• Nebulization
• Mask/spacer