Definition
• High-pitched sound of turbulent airflow in upper airway indicates airway obstruction
• Inspiratory stridor usually indicates obstruction above the vocal cords
• Expiratory stridor usually indicates obstruction below the vocal cords
Differential Diagnosis
• Causes include croup, epiglottitis, and bacterial tracheitis (BT may be the most freq life-threatening upper airway infection currently) (Pediatrics 2006;118:1418)
• Consider differential diagnosis anatomically based on inspiratory or expiratory stridor
• Nose: Inspiratory stridor, snoring; in neonates consider choanal atresia
• Pharynx: Gurgling/muffled voice
• Afebrile: Macroglossia, micrognathia, tonsil/adenoid hypertrophy
• Febrile: Retropharyngeal/peritonsillar abscess
• Larynx: High-pitched inspiratory stridor, voice change, hoarseness
• Afebrile: Laryngomalacia, laryngeal web, cyst, vocal cord paralysis, laryngotracheal stenosis, intubation, foreign body, cystic hygroma, subglottic hemangioma, laryngospasm, psychogenic stridor, vocal cord paralysis
• Febrile: Croup, epiglottitis
• Trachea: Insp & exp stridor: Tracheomalacia, bact tracheitis, external compression, TEF
Croup (Laryngotracheobronchitis)
• Characterized by barking cough, +/− inspiratory stridor, +/− respiratory distress
• Peak incidence 1–2 yo, Sept to Dec, M > F. Parainfluenza virus accounts for >50%, the next most common cause is RSV (Pediatrics 1983;71:871)
• Mild: Dexamethasone 0.6 mg/kg PO/IM ↓ rpt visits, length of sx, and parental stress, and ↑ sleep (N Engl J Med 2004;351:1306). Also consider cool mist, hydration, & antipyretics
• Can use oral prednisolone 1–2 mg/kg PO; t1/2 of prednisolone 24 hr; t1/2 of Dex 32 hr
• Moderate to severe:
• Mist tent or humidified oxygen near child’s face (not supported by Cochrane review)
• Dexamethasone 0.6 mg/kg PO/IM/IV (N Engl J Med 1998;339:498; meta-analysis in BMJ 1999;319:595)
• Equivalence of PO vs. IM dosing shown in study of moderate croup. (Pediatrics 2000;106:1344)
• Racemic epi (2.25%) 0.05 mL/kg/dose in 3 mL NS (max 0.5 mL) q15 min up to 3× PRN, watch HR (Pediatrics 1992;89:302)
• Cochrane review (CD006619) supported benefit at 30 min post-nebulized epi but not at 2 hr and 6 hr post though decreased rate of hospitalization
• If epi given, need obs (effects wears off in 2 hr). Obs in ED for min 4–6 hr
• Decrease epi dose for known cardiac disease
Epiglottitis
• Usually 2/2 Hib. Incidence of Hib ↓ by >99% since intro of conj vaccine in 1998 (MMWR 2002;51:234). P/w toxic child, drooling, sitting forward, stridor
• True emergency requiring immediate intubation in controlled environment
(if possible), any manipulation of child may cause full obstruction
• Give O2 as accepted by child, allow parent to accompany child to allay anxiety
• Summon senior pediatrician, anesthesiologist, and ENT or pediatric surgeon
• If unstable, intubate emergently; bag-mask w/ high pres, may need to disable pop-off
• If stable with high suspicion (toxic, febrile, leaning forward, audible stridor, uncertain vaccination record) escort pt to OR for laryngoscopy/intubation
• If moderate/low suspicion, obtain lat neck x-ray (thumbprint sign), will agitate them
• Once airway is secure, check CBC/diff, cx of blood and epiglottis, start Abx (such as ceftriaxone) covering Hib, S. pneumo, and Grp A strep
Bacterial Tracheitis (Pediatrics 2006;118:1418; Emerg Med Clin North Am 2007;25:961)
• Commonly seen in fall/winter, 6 mo–8 yr
• Presentation: Viral prodrome followed by acute onset of toxic appearance, high fever (mean 101.8°F/38.8°C), cough, resp distress. Unlikely to drool, may be able to lie flat
• Management: To OR for endoscopy to obtain sample for GS and cultures and intubation. If intubating in ER consider smaller ETT than usual because of airway edema
• Abx to cover S. aureus, S. pneumo, M. catarrhalis, H. flu, and alpha-hemolytic strep
• CXRs usually normal or similar to croup (steeple sign), blood cx usually negative
Lemierre’s Disease (Pediatr Crit Care Med 2003;4:107; Am J Otolaryngol 2010;31:38; J Emerg Med 2010;39:436; J Clin Microbiol 2003;41:3445)
• Jugular vein suppurative thrombosis preceded by pharyngitis or dental infections; internal jugular vein thrombophlebitis leads to metastatic complications; most commonly caused by Fusobacterium necrophorum; may present with respiratory distress
• Criteria for diagnosis:
• Previous oropharyngeal infection
• Septicemia following oropharyngeal infection
• Swelling or unilateral tenderness of the neck, jaw
• Metastatic abscesses to the lung, liver, kidneys, or joints
• Fusobacterium necrophorum isolated from blood cultures or abscess aspiration
• Rapid progression
• Diagnostic procedures: Blood culture, ultrasound, CT neck with contrast
• Treatment: ABCs, antibiotics, e.g., ampicillin–sulbactam and metronidazole. Consider surgery and anticoagulation
Diagnostic Studies for Stridor in General
• Initial eval w/ CXR lat/AP neck film; ENT (direct laryngoscopy), consider fluoro if available. Determine cause: Start initial management, but etiology can define specific treatments