In our ongoing endeavor to provide free, open access medical education, we’re thrilled to report that our newest addition to the Med School Tutors Podcast has launched! Introducing “Peds in 10,” our Pediatrics Podcast Master Class Series.
Whether you want to get a better handle on diagnosing pediatric respiratory distress while you hit the gym, drive/walk home, or study, we’ve shared two ways you can listen to the podcast and review the abbreviated transcript for easy reference below:
You can also listen to the episode in Apple’s Podcasts app.
Pediatric Respiratory Distress:
Welcome back to the Med School Tutors podcast, your resource for high yield tips and proven guidance to help reduce stress and give you tangible tools for success — from pre-med through residency and the boards. This episode is the first edition of our Pediatric Master Class series entitled “Peds in 10,” with Dr. Eli Freiman — a board-certified pediatrician and current Pediatric Emergency Medicine fellow. In these Peds in 10 episodes, we’ll go over a high-yield approach to pediatric diagnosis, all in about 10 minutes. This episode is going to discuss pediatric respiratory distress. Let’s get started.
In general acute pediatric respiratory disease can be broken up into two large categories: Non-infectious and infectious causes. Within each category it’s helpful to break it further down anatomically, thinking about supraglottic, subglottic, and parenchymal disease. Let’s look at each of these in turn.
We’ll start with the non-infectious causes of respiratory distress in pediatric patients:
The most classic non-infectious supraglottic cause of respiratory distress in children is angioedema. The most important, and don’t miss cause of angioedema is anaphylaxis. We’ll also talk about Laryngomalacia which can cause intermittent glottic obstruction. And always be on the lookout for children who might have an acute upper airway foreign body obstruction!
Anaphylaxis:
Definition: Life threatening multisystem syndrome caused by generalized mast cell activation.
Causes: Type 1 IgE hypersensitivity reaction
S/Sx: 4 system involvement: Skin/mucosa (hives/angioedema), respiratory (SOB/wheeze), GI (abd pain/V/D), and CV (syncope/hypotension/shock).
DDx: Urticarial syndromes (urticaria multiforme), asthma, syncope, Shock (including sepsis)
Diagnosis: Clinical based on the above criteria, and can be slightly different if the patient has a known allergen or known exposure.
Management/Treatment: Early intramuscular epinephrine, as time to EPI has been shown to be associated with decreased morbidity and mortality. Antihistamines can be used as an adjunct. Steroids are controversial.
Laryngomalacia:
Definition: Collapse of the supraglottic structures during inspiration
Important Epi: Most common congenital anomaly of the larynx. Presents in infancy.
Causes: Poorly developed cartilage, NM disease leading to hypotonia, redundant soft tissue
S/Sx: Inspiratory stridor, poor growth
Diagnosis: Clinical – ENT can do a laryngoscopy to confirm
Management/Treatment: Conservative if minor. If mod-severe, calorie supplementation and ENT referral for possible surgery.
When we think about non-infectious subglottic causes of respiratory distress in children, we generally think of foreign bodies or internal or external tracheal compression. The trachea can be compressed by things such as vascular rings or tumors. Since these are relatively rare causes of respiratory distress we won’t discuss them further here but let’s talk a little about foreign bodies.
Foreign Body Obstruction:
Definition: Partial or fully occluding foreign body anywhere from supraglottic space to large airways
Important Epi: 3mo – preschool age
Causes: Classically round/smooth objects – grapes, hard candies, small toy pieces, cut up hot dogs, etc.
S/Sx: Choking, resp distress, cough. If complete upper airway obstruction – stridor or silent. Lower airway – wheeze, cough, hemoptysis
Diagnosis: CXR for radiopaque or signs of air trapping on decubitus films. Sometimes needs nasopharyngoscopy or bronchoscopy.
Management/Treatment: ABCs! Don’t irritate the child as this can dislodge the object and turn a partial obstruction into a full obstruction. These patients typically require OR for removal.
Our group of non-infectious parenchymal causes of respiratory distress includes one of the most classic pediatric diagnoses: Asthma. There are a couple less-common ones here too. Never forgot acute pulmonary edema in your patients with heart disease.
Asthma:
Definition: Chronic inflammatory lower airway disease with smooth muscle hypertrophy and mucous overproduction that leads to at least partially reversible lower airway obstruction
Important Epi: Most common chronic disease of childhood. Most present before 5 y/o.
Causes: Nature vs nurture. Ongoing discussion. Many known risk factors.
S/Sx: Resp distress: Tachypnea, inc WOB, wheeze. Chronic cough, worse at night.
DDx: Infectious lower resp disease, allergic reaction/ anaphylaxis
Diagnosis: Clinical +/- spirometry
Management/Treatment: Sick: inhaled bronchodilators (SABA) and oral glucocorticoids. Not-sick: ICS. Good AAP.
Pneumothorax:
Definition: Collection of air that is located within the thoracic cage between the visceral and parietal pleura. Spontaneous means absence of trauma.
Important Epi: 16-24 years old, more common in males than females.
Causes: Primary spontaneous – no underlying disease. Secondary spontaneous means underlying disease such as CF.
S/Sx: Sudden onset of dyspnea and pleuritic chest pain, +/- hypoxemia. If tension, you can start to see CV compromise, such as severe tachycardia, hypotension and shock.
Diagnosis: Typically CXR
Management/Treatment: supplemental oxygen. Thoracostomy tube if large. VATS/pleurodesis if recurrent.
That about does it for our key non-infectious causes of acute respiratory distress. Now let’s talk about the important infectious causes of respiratory distress. Similar to before, we should discuss supraglottic, subglottic, and parenchymal causes.
Our key infectious supraglottic pathologies are retropharyngeal abscess and epiglottitis.
Retropharyngeal Abscess:
Definition: Suppurative deep neck space infection of the prevertebral soft tissue
Important Epi: Typically toddlers – preschool aged children
Causes: GAS > Staph > resp anaerobes
S/Sx: Fever, neck stiffness, pain w/ neck extension, dysphagia
DDx: Rule out other causes of resp distress and sore throat – epiglottitis, croup, tracheitis, PTA, meningitis, foreign bodies, angioedema.
Diagnosis: Plain films of the neck show widening of the prevertebral space. CT of the neck is preferred if cross-section imaging is required.
Management/Treatment: ABCs if respiratory compromise. Discuss w/ ENT about IV abx vs surgical drainage.
Epiglottitis:
Definition: Bacterial infection of the epiglottis and surrounding structures
Important Epi: Generally toddlers – school aged children, especially if under-immunized.
Causes: HIB – now reduced due to vaccination. other species of HI (Non-typable), GAS, Strep pneumo, Staph can rarely be a cause
S/Sx: Acute progressive upper airway obstruction. These patients look really sick when they present. High fever, drooling, tripoding. Maybe stridor, maybe not depending on degree of obstruction.
Diagnosis: Clinical diagnosis. CBC shows leukocytosis. Classic “thumbprint” sign on lateral radiograph of neck.
Management/Treatment: Anesthesia needs to nasotracheal intubate these patients. Avoid irritating the child at all. Abx therapy is with cephalosporins.
Just below those sit our infectious subglottic causes which present similarly and are both really important pediatric pathologies: croup and bacterial tracheitis.
Croup:
Definition: Inflammation and edema of the subglottic region (larynx/trachea/bronchi)
Important Epi: 6mo – 4y, often in the fall and winter
Causes: Viral group – parainfluenza viruses.
S/Sx: URI prodrome -> barky cough & inspiratory stridor. Worse at night.
DDx: Tracheitis, angioedema
Diagnosis: Clinical + steeple sign on plain film
Management/Treatment: Systemic corticosteroids +/- aerosolized epinephrine.
Bacterial Tracheitis:
Definition: Bacterial infection of the trachea
Important Epi: Common in children w/ anatomical abnormalities/trach in situ/recent instrumentation or congenital anomalies of the airway
Causes: S. aureus, Strep, H flu, moraxella
S/Sx: VERY SICK. Croup but sicker. High fever, stridor, significant resp distress, coughing up purulent material
Diagnosis: Clinical, trach aspirate, bronchoscopy
Management/Treatment: Broad antibiotics, respiratory support.
Next come the all-important infectious parenchymal causes of pediatric acute respiratory distress, which include two more key pediatric diagnoses: bronchiolitis and pneumonia. I’ll also make note of a thankfully-rare, but can’t-miss diagnosis in pertussis.
Bronchiolitis:
Definition: Widespread inflammation of the bronchioles with mucous plugging
Important Epi: Most common lower resp infection in children < 2. November to April. Worse in children with chronic comorbidities and preemies.
Causes: Many viruses, the most common of which is RSV.
S/Sx: URI progressive to tachypnea, retractions and “washing machine” breath sounds, hypoxemia and apnea (youngest babies)
DDx: URI, bacterial PNA
Diagnosis: Completely clinical. Labs and CXR are generally not done.
Management/Treatment: Supportive care only — including fluids, oxygen and observation as needed
Pneumonia (CAP vs aspiration):
Definition: Infection and inflammation of the parenchymal lung spaces
Important Epi: RISK factors > age factors. Smoke exposure, crowded living conditions (shelters, multiple siblings)
Causes: Viral vs bacterial. Viruses are more common a cause in pediatric populations. Flu, adeno, paraflu, HMPV, RSV. Bacterial causes are dominated by Strep Pneumo. Older groups can get walking PNA = mycoplasma and chlamydia pneumoniae.
S/Sx: Fever, tachypnea, hypoxemia.
Diagnosis: Suggested by clinical exam. Diagnosed with CBC and CXR. Infiltrate on XR. On boards there will be a lobar infiltrate in bacterial PNA, interstitial infiltrate with viral; this is not always true in clinical practice. If mycoplasma can sent serologies or PCR based on local lab availability.
Management/Treatment: Oxygen, antibiotics (if bacterial), supportive care.
Pertussis:
Definition: Respiratory infection caused by Bordetella pertussis
Important Epi: Adolescents/adults with waning immunity infect un/underimmunized children and babies. Infants younger than 6 months at risk for severe disease
S/Sx: Three Stages: Catarrhal state (1-2wk URI) -> Paroxysmal stage (1-6wk paroxysmal coughs +/- whoops [youngest patients don’t present with whoop due to lack of necessary musculature], apnea, cyanosis, vomiting) -> Convalescent (wk to months) less frequent over time
DDx: CAP, viral resp infection
Diagnosis: Lymphocytosis! PCR for B. pertussis
Management/Treatment: Hospitalization, Macrolides, isolation, contact tracing, close contacts should also be treated empirically with antibiotics to prevent disease and further spread.
That’s all for this episode! Thanks for listening to 10-minute pediatrics and we’ll see you next time!
