Treatment of Pediatric Airway Disorders: Beyond Tracheostomy Meredith N. Merz, M.D. Nationwide Children’s Hospital Department of Pediatric Otolaryngology April 6, 2011
Objectives 1. Identify the most common causes of stridor in the pediatric population. 2. Discuss diagnostic techniques in a child with stridor. 3. Understand the pathogenesis of acquired subglottic stenosis and the difference between congenital and acquired stenosis. 4. Discuss treatment options for the most common airway disorders in children.
Laryngeal Function Three Main Functions: 1. Acts as an airway from pharynx into trachea and lungs 2. Instrument of phonation 3. Protects the lower airways Closure of glottis during swallowing Epiglottis folds posteriorly over glottis Cough
Infant Larynx Larynx is more rostral Epiglottis apposes the soft palate Hyoid bone is impacted on thyroid cartilage Vocal cords are oriented transversely Epiglottis is short and curled in on itself Arytenoids are anteriorly oriented and involve half the length of the vocal folds
Infant Larynx Bosma JF. Anatomy of the Infant Head. Baltimore, Johns Hopkins University Press, 1986, pp 366-367.
Stridor Harsh sound caused by turbulent airflow Implies partial airway obstruction Location of lesion determines character of stridor Supraglottic Extrathoracic Intrathoracic
Physics Review… Poiseuille’s Law Q = [πd4 (P1-P2)] / 128ν Flow within a system is related to the radius of the tube to the fourth power Resistance is related to the inverse of the radius to the fourth power Bernouilli’s Law: W = PAv As velocity increases through a constant area the pressure on the wall of the lumen decreases A region of anatomic narrowing is predisposed to collapse further with increased turbulent airflow
Localizing Stridor Supraglottic obstruction With inspiration the loosely supported supraglottic structures collapse. Increased turbulence causes increased constriction Stridor is inspiratory and high pitched Extrathoracic obstruction Airway is affected equally by inspiration and expiration Stridor is biphasic, often accompanied by increased work of breathing Intrathoracic obstruction Relative positive pressures of expiratory forces narrow the airway lumen, resulting in increased constriction Stridor is expiratory and “musical”; Wheeze
Airway Evaluation- History Age at onset Onset: acute, chronic, progressive Prior respiratory problems Birth history Prior intubation GERD symptoms Wheezing episodes Feeding problems: FTT, weight gain Choking episodes Aggravating factors
Airway Evaluation- Initial Examination Inspection General appearance and position, color, retractions, level of consciousness Auscultation Mouth/Nose, Neck and Chest Repositioning Prone/Supine, lateral, jaw thrust Is there acute distress? Nasal flaring Tachypnea Cyanosis Retractions Tripod position
Flexible Nasopharyngoscopy Gold Standard for office evaluation Assess nares/ choanae Assess adenoid and lingual tonsil Assess laryngeal structures Assess TVC mobility Drawback: Poor for assessing subglottic structures
Radiologic Evaluation Plain films have limited utility PA/ Lateral Neck Airway Fluoroscopy Evaluate the dynamics of respiration Inspiratory/ Expiratory CT Scan
Rigid Laryngoscopy and Bronchoscopy Indications: To establish diagnosis or evaluate for synchronous lesions (after flexible exam) Severe or progressive stridor Cyanosis or apnea concerns Radiologic abnormalities Parental or physician anxiety Foreign body evaluation
Congenital Disorders of the Larynx Laryngomalacia 60% Congenital subglottic stenosis 16% Vocal cord paralysis 13% All Others: 7% Congenital laryngeal web Laryngocele and Saccular cyst Laryngeal/ Laryngotrachealesophogeal Cleft Vascular lesions Holinger, LD. Etiology of Stridor in the Newborn, Infant, and Child. Annals of ORL, 1980; 89: 397-400.
Laryngomalacia Most common cause of stridor in infants Presentation Staccato/ Coarse inspiratory stridor Worse with exertion, feeding, crying Noisy breathing generally begins at about 2-4 weeks of age Office Evaluation Character of stridor Positional changes Flexible nasopharyngoscopy
Laryngomalacia • Endoscopic appearance • Omega epiglottis • Foreshortenend aryepiglottic folds • Cuneiform and corniculate prolapse
Laryngomalacia Classification Type I Type II Type III Type IV Type V Kay DJ, Goldsmith AJ. Laryngomalacia: A Classification System and Surgical Treatment Strategy. Ear Nose Throat J. 2006 May;85(5):328-31, 336.
Laryngomalacia Vast majority are mild Parental reassurance & education Transient worsening, gradual improvement Weight gain issues GERD issues- Consider GERD treatment if there is evidence on endoscopy
Severe Laryngomalacia Respiratory difficulty Apnea/ Cyanosis/ ALTE Feeding difficulty Failure to thrive Uncontrolled GERD Sleep apnea CNS abnormalities
Severe LaryngomalaciaSurgical Treatment Supraglottoplasty- Aryepiglottic fold division +/- Excision of corniculate cartilages
Severe LaryngomalaciaEpiglottic Procedures Epiglottic Procedures: Epiglottoplasty- Excision of a V-shaped wedge of tissue from the epiglottis Epiglottopexy- Epiglottis is pexied to the base of tongue with stitch/ laser Whymark AD, Clement WA, Kubba H, Geddes N. Laser Epiglottopexy for Laryngomalacia. Archives of Otolaryngology Head and Neck Surgery, 2006; 132: 978-982.
Vocal Cord Paralysis Bilateral: Airway issues, Aspiration issues Expectant (can take years to resolve) Close monitoring of O2 sat, apnea, weight gain Tracheotomy Posterior laryngeal expansion Botox (for spastic paralysis) Cordotomy Arytenoidectomy Re-innervation procedures Unilateral: Voice Issues, Aspiration Issues Observation Vocal Cord Injection Thyroplasty