Morning Report

08/21/2009

Ali F. Ahrabi, MD

Stridor

Harsh, high-pitched, musical sound produced by turbulent airflow through a partially obstructed airway

May be inspiratory, expiratory, or biphasic depending on its timing in the respiratory cycle

Inspiratory stridor suggests an extrathoracic lesion (eg, laryngeal, nasal, pharyngeal)

Expiratory stridor implies an intrathoracic lesion (eg, tracheal, bronchial)

History

History

Age of onset, duration, severity, and progression; precipitating events (eg, crying, feeding); positioning (eg, prone, supine, sitting); quality and nature of crying; presence of aphonia; and other associated symptoms (eg, paroxysms of cough, aspiration, difficulty feeding, drooling, sleep disordered breathing).

Perinatal history is especially important and should include direct questioning regarding maternal condylomata, endotracheal intubation use and duration, and presence of congenital anomalies

Feeding and growth history, developmental history

Physical Exam

PE

Heart and respiratory rates, cyanosis, use of accessory muscles of respiration, nasal flaring, level of consciousness, and responsiveness

Physical examination of a patient with suspected acute epiglottitis is contraindicated

Note the presence of infection in the oral cavity; crepitations or masses in the soft tissues of the face, neck, or chest; and deviation of the trachea

Use care when examining (especially palpating) the oral cavity or pharynx because sudden dislodgement of a foreign body or rupture of an abscess can cause further airway compromise

PE

Drooling from the mouth suggests poor handling of secretions, Dysphagia

Observe the character of the cough, cry, and voice The presence of fever and toxicity generally implies

serious bacterial infections Careful auscultation of the nose, oropharynx, neck, and

chest helps to discern the location of the stridor special attention to craniofacial morphology, patency of

the nares, and cutaneous hemangiomas

Differential Diagnosis

Differential – Acute onset

Laryngotracheobronchitis (croup) the most common cause of acute stridor in children 6 months to 2 years barking cough that is worst at night low-grade fever

Aspiration of foreign body 1-2 years food such as nuts, hot dogs, popcorn, and hard candy history of coughing and choking that precedes development of respiratory

symptoms Bacterial tracheitis

uncommon younger than 3 years secondary infection (most commonly due to Staphylococcus aureus) following

a viral process (commonly croup or influenza)

Differential – Acute onset

Retropharyngeal abscess complication of bacterial pharyngitis younger than 6 years abrupt onset of high fevers, difficulty swallowing, refusal to feed,

sore throat, hyperextension of the neck, and respiratory distress Peritonsillar abscess

infection in the potential space between the superior constrictor muscles and the tonsil

common in adolescents and preadolescents. patient develops severe throat pain and trouble swallowing or

speaking

Differential – Acute onset

Spasmodic croup (acute spasmodic laryngitis) most commonly in children aged 1-3 years presentation may be identical to croup

Allergic reaction (ie, anaphylaxis) hoarseness and inspiratory stridor may be accompanied by

symptoms (eg, dysphagia, nasal congestion, itching eyes, sneezing, wheezing) that indicate the involvement of other organs

Epiglottitis medical emergency most commonly in children aged 2-7 years Clinically, the patient experiences an abrupt onset of high-grade

fever, sore throat, dysphagia, and drooling

Differential - Chronic

Laryngomalacia the most common cause of inspiratory stridor in the neonatal

period and early infancy accounts for up to 75% of all cases of stridor Stridor may be exacerbated by crying or feeding Placing the patient in a prone position with the head up improves

the stridor supine position worsens the stridor usually benign and self-limiting and improves as the child

reaches age 1 year

Differential - Chronic

Subglottic stenosis inspiratory or biphasic stridor congenital subglottic stenosis occurs when an incomplete canalization

of the subglottis and cricoid rings causes a narrowing of the subglottic lumen.

acquired stenosis is most commonly caused by prolonged intubation Vocal cord dysfunction

second most common cause of stridor in infants unilateral vocal cord paralysis can be congenital or secondary to

trauma at birth or time of cardiac or intrathoracic surgery bilateral vocal cord paralysis

Pt present with aphonia and a high-pitched stridor that may progress to severe respiratory distress.

It is usually associated with CNS abnormalities, such as Arnold-Chiari malformation or increased intracranial pressure

Differential - Chronic

Laryngeal dyskinesia, exercise-induced laryngomalacia, and paradoxical vocal fold motion are other neuromuscular disorders

Laryngeal webs are caused by an incomplete recanalization of the laryngeal lumen during embryogenesis

Laryngeal cysts

Laryngeal hemangiomas (glottic or subglottic) half of them are accompanied by cutaneous hemangiomas in the

head and neck Patients usually present with inspiratory or biphasic stridor that

may worsen as the hemangioma enlarges usually regress by age 12-18 months

Differential - Chronic

Laryngeal papillomas secondary to vertical transmission of the human papilloma virus

in maternal condylomata or infected vaginal cells to the pharynx or larynx of the infant during the birth

Tracheomalacia most common cause of expiratory stridor

Tracheal stenosis secondary to extrinsic compression

Lab

ABG to evaluate oxygenation

Other labs as dictated by the clinical situation

Generally, no investigations are required for mild stridor

Imaging

Anteroposterior (AP) and lateral radiographs of the neck and chest

Barium esophagram may be performed if vascular compression, tracheoesophageal fistula, GER, or neurological dysfunction is suspected

Contrast-enhanced CT scanning can demonstrate mediastinal masses or aberrant vessels

An MRI may be helpful in delineating lesions of the upper airway and vascular anomalies

Direct laryngoscopy and bronchoscopy is the criterion standard for making a diagnosis in infants and children with stridor

Treatment

As per severity of the presentation and underlying diagnosis

Ensure airway is adequate O2 as required Comfortable positioning If airway compromised or child in severe distress or

hypoxia: Anesthesia/ENT and intensive care

Treatment

Croup (infectious or spasmodic)

Croup Severity

Inspiratory stridor None - 0 points Upon agitation - 1

point At rest - 2 points

Retractions Mild - 1 point Moderate - 2 points Severe - 3 points

Air entry Normal - 0 points Mild decrease - 1 point Marked decrease - 2 points

Cyanosis None - 0 points Upon agitation - 4 points At rest - 5 points

Level of consciousness Normal - 0 points Depressed - 5 points

Croup Treatment

The first rule of management is to keep the child as comfortable as possible

monitoring of the heart rate, respiratory rate, respiratory mechanics, and pulse oxymetry

Cool mist  Randomized studies of children with moderate-to-severe croup

revealed no difference in outcome between those who received cool mist and those who did not

The use of hot steam should be avoided because scalding has been reported

Mist tents can disperse fungus and molds if not properly cleaned and separates the child from the parent

Croup Treatment

Corticosteroids (decrease hospitalization rates by 86%) single dose of dexamethasone has been shown to be effective in

reducing the overall severity of croup if administered within the first 4-24 hours after onset of illness

The long half-life of dexamethasone (54 h)  Dexamethasone (0.15 mg/kg) is as effective as 0.3 mg/kg or 0.6

mg/kg in relieving symptoms of mild-to-moderate croup same efficacy if administered intravenously, intramuscularly, or

orally. A single oral dose of prednisolone (2 mg/kg) resulted in more

return visits than a single oral dose of dexamethasone (0.6 mg/kg)

Inhaled budesonide has also proven to be effective but is more expensive

Croup Treatment

Nebulized racemic epinephrine

is typically reserved for patients in moderate-to-severe distress works by adrenergic stimulation

constriction of the precapillary arterioles, thereby decreasing capillary hydrostatic pressure fluid resorption from the interstitium and improvement in the laryngeal mucosal edema

beta-2-adrenergic activity leads to bronchial smooth muscle relaxation and bronchodilation

Can cause rebound effect

A child who is symptomatic enough to receive epinephrine may be discharged after at least 3 hours of observation

Croup Treatment

Heliox is a metabolically inert, nontoxic gas that is combined with

oxygen.  It has low viscosity and low specific gravity, which allows for

greater laminar airflow through the respiratory tract Helium decreases the force necessary to move the gas through

the airways and decreases the mechanical work of respiratory muscles, which is clinically seen as less respiratory distress 

It has been shown to improve symptoms in very severe croup that failed to improve with racemic epinephrine