Basics
Description
- High-pitched audible wheezing and vibratory harsh sounds mainly on inspiration.
- Impedance of air movement through the upper airway.
- It implies a laryngotracheal airway obstruction.
Etiology
- Congenital:
- Laryngomalacia
- Laryngeal webs/rings
- Vocal cord dysfunction:
- Congenital
- Surgical injury
- Postintubation trauma
- Thyroid malignancy
- Mediastinal mass
- Neural abnormalities (e.g., meningomyelocele, Arnold " Chiari malformation)
- Subglottic stenosis:
- Postoperative scarring
- After radiation therapy
- After prolonged endotracheal intubation
- Subglottic hemangioma
- Infection:
- Bacterial tracheitis
- Epiglottitis
- Viral croup
- Peritonsillar abscess
- Retropharyngeal abscess
- Supraglottitis
- Uvulitis (e.g., Quincke disease)
- Ludwig angina
- Diphtheria
- Tetanus
- Extrinsic compression:
- Trauma
- Hematoma
- Vascular anomalies (e.g., rings)
- Intraluminal obstruction of the trachea:
- Foreign body
- Tracheomalacia
- Cyst
- Invasive tumors
- Squamous cell
- Lymphomas
- Thyroid masses/carcinomas
- Laryngeal or tracheal papilloma
- Angioedema
Diagnosis
Signs and Symptoms
History
- Breathing difficulties
- Audible stridor (worsens with feeds, crying, and on lying supine)
- Muffled hoarseness "Hot potato " voice in adults
- Feeding difficulties in infants (amount of feeds and regurgitation with GERD)
- Apneas and cyanotic attacks
- Antenatal, perinatal, and birth events (e.g.. resuscitation at birth with intubation)
- Anxiety
- Cough
- Drooling
- Sore throat
Physical Exam
- Tachypnea
- Dyspnea
- Dysphagia
- Fever
- Respiratory distress, worse with agitation
- Nasal flaring, intercostal retractions, subcostal indrawing
- Paradoxic diaphragmatic movement (late finding)
- Audible stridor (inspiratory/biphasic stridor)
- Cyanosis
- Trismus:
- Peritonsillar abscess, retropharyngeal abscess, Ludwig angina
Essential Considerations
- Visualization of the upper airway:
- Radiographic if symptoms very mild; be careful!
- Direct visualization in OR with a surgeon prepared to perform a cricothyrotomy or tracheostomy is the safest approach.
Diagnosis Tests & Interpretation
Lab
These tests are not helpful and thus avoidable; may upset a child even more.
Imaging
Radiograph of lateral and posteroanterior neck and chest:
- Not essential
- Only done in extremely mild cases or when there is suspicion of foreign body aspiration
Diagnostic Procedures/Surgery
- Fiberoptic laryngoscopy:
- Should be performed with an intubating fiberoptic laryngoscope in a setting where a rapid surgical airway can be obtained
- Direct laryngoscopy:
- Diagnostic study of choice
- Should be performed in a setting where a rapid surgical airway can be obtained
Differential Diagnosis
- Stertor:
- Pharyngeal obstruction while wheezing
- Bronchospasm
- Malingering (patient breathing against a closed glottis)
Treatment
Pre-Hospital
- Keep child calm, with mother if possible.
- Supply blow-by oxygen.
- Maintain adequate airway.
- Use bag-valve-mask (BVM) if respiratory status deteriorates.
- Intubate if BVM ineffective.
- Provide rapid transport with ED notification.
Initial Stabilization/Therapy
- In children: Avoid agitation. Supply blow-by oxygen.
- Use 100% nonrebreathing-type face mask
- Pulse oximetry to check oxygen saturation and monitoring of vitals.
- Avoid agitating child.
- Watch for rapid deterioration of respiratory status.
Ed Treatment/Procedures
- Airway management:
- Stridor comprises a difficult airway passage:
- Be prepared to create an airway surgically before intubation.
- If time permits, perform intubation in OR with surgeon and pediatric anesthesiologist present.
- Intubate with tube 1 or 2 sizes smaller than would be normally used.
- Oral awake intubation:
- Ketamine induction
- Patient is sedated but continues to ventilate during procedure.
- Avoid blind nasotracheal intubation.
- Oral intubation is preferred initially. After oral intubation the oral tube is replaced by a nasal tube of the same size.
- Provide surgical airway if intubation fails or sudden deterioration in respiratory status occurs.
- Postintubation ceftriaxone in cases of infectious cause
- Sedation/paralysis for duration of intubated status after airway is secured.
- Extubation could be attempted when an air leak develops around the tracheal tube, which can take around 2 " 10 days.
- Controversies:
- Heliox therapy
- Racemic epinephrine therapy
- Early intubation
Medication
- Atropine: 0.02 mg/kg IV
- Ceftriaxone: 1 " 2 g IV
- Diazepam: 2 " 10 mg IV (peds: 0.2 " 0.3 mg/kg)
- Etomidate: 0.3 mg/kg IV
- Fentanyl: 3 Όg/kg IV
- Ketamine: 1 " 2 mg/kg IV or 4 " 7 mg/kg IM
- Lidocaine: 1.5 mg/kg IV
- Midazolam: 1 " 5 mg IV (0.07 " 0.3 mg/kg for induction)
- Vecuronium: 0.1 mg/kg IV
- Nebulized epinephrine: 1 mL of 1:1,000 diluted to 5 mL with normal saline
- Dexamethasone: 0.15 mg/kg oral/IV
Follow-Up
Disposition
Admission Criteria
All cases of stridor that are not completely resolved during the ED course mandate admission of patient to hospital.
Discharge Criteria
Stridor fully resolved or identified as a nonstridorous abnormal breathing sound.
Issues for Referral
Consultation with an otolaryngologist or a pediatric surgeon prior to airway visualization
Pearls and Pitfalls
- Attempting visualization of the airway without the backup needed for an emergency tracheostomy is a pitfall.
- Laryngoscopy findings determine the indications for other complementary exams such as barium swallow, polysomnography, echocardiography, CT, or magnetic resonance scans of neck and thorax.
- Patients, especially children with stridor, often have associated abnormalities involving respiratory tract which mandates not only endoscopic exam of the larynx, but also the tracheobronchial system.
Additional Reading
- Boudewyns A, Claes J, Van de Heyning P. Clinical practice: An approach to stridor in infants and children. Eur J Pediatr. 2010;169(2):135 " 141.
- Daniel M, Cheng A. Neonatal stridor. Int J Pediatr. 2012;2012:859104.
- Halpin LJ, Anderson CL, Corriette N. Stridor in children. BMJ. 2010;340:c2193.
- Mellis C. Respiratory noises: How useful are they clinically? Pediatr Clin North Am. 2009;56(1):1 " 17, ix.
- Walaschek C, Forster J, Echternach M. Vocal cord dysfunction without end? Klin Padiatr. 2010;222(2):84 " 85.
Codes
ICD9
- 748.2 Web of larynx
- 748.3 Other anomalies of larynx, trachea, and bronchus
- 786.1 Stridor
- 478.74 Stenosis of larynx
- 464.10 Acute tracheitis without mention of obstruction
- 464.11 Acute tracheitis with obstruction
- 464.1 Acute tracheitis
- 464.4 Croup
ICD10
- Q31.0 Web of larynx
- Q31.5 Congenital laryngomalacia
- R06.1 Stridor
- J38.6 Stenosis of larynx
- J04.10 Acute tracheitis without obstruction
- J04.11 Acute tracheitis with obstruction
- J04.1 Acute tracheitis
- J05.0 Acute obstructive laryngitis [croup]
SNOMED
- 70407001 Stridor (finding)
- 55490007 Congenital laryngeal stridor (disorder)
- 297159008 Laryngeal web (disorder)
- 22668006 Subglottic stenosis (disorder)
- 58596002 inspiratory stridor (finding)
- 62994001 Tracheitis (disorder)
- 71186008 Croup (disorder)