COCLIA Pediatrics:

Glottic and Subglottic Stenosis

Samuel OstrowerMarch 24, 2008

1. Review the Cotton stenosis grading system

Cotton SGS Grading Schema

• Grade I: less than 70% stenosis

• Grade II: 70% to 90%

• Grade III: More than 90%; identifiable lumen is present (no matter how narrow)

• Grade IV: Complete obstruction; no lumen

Subglottic Dimensions

• The normal subglottic lumen diameter in the full-term neonate is 4.5 to 5.5 mm

• Normal subglottic lumen in premature babies is about 3.5 mm.

• A subglottic diameter of 4 mm or less in a full-term neonate is considered to be narrowed.

• Of note, 1mm circumferential edema in subglottis decreases cross sectional area by 60%

2. Compare and contrast pediatric vs. adult laryngeal anatomy

Embryology

Embryology

Adult vs. Pediatric Larynx

• At birth, larynx is 1/3 the size of adult larynx

• Vocal process ½ total TVC length in infants and ¼ total TVC length in adult

• Subglottis narrowest part of airway in infants, glottis narrowest in adult

3. Review the histopathologic classification of congenital subglottic

stenosis

Congenital SGS

• Congenital subglottic stenosis is the third most common congenital disorder of the larynx after laryngomalacia and recurrent laryngeal nerve paralysis

• Congenital SGS classified as either membranous or cartilaginous type

Membranous SGS

• Fibrous soft-tissue thickening of the subglottic area – increased fibrous connective tissue – hyperplastic, dilated mucous glands with no

inflammatory reaction

• Usually circumferential, with the narrowest area 2 to 3 mm below the true vocal cords

Cartilaginous SGS

• More variable

• Most common type is a thickening or deformity of the cricoid cartilage causing a shelf-like plate of cartilage extending from anterior to posterior within lumen

Cartilaginous Stenosis • Cricoid cartilage deformity

– Normal shape• Small for infant's size

– Abnormal shape • Large anterior lamina

• Oval (elliptic shape)

• Large posterior lamina

• Generalized thickening

• Submucous (occult) cleft

• Other congenital cricoid stenosis

– Trapped first tracheal ring

Soft-Tissue Stenosis • Submucosal fibrosis • Submucosal gland

hyperplasia • Granulation tissue

4. List the etiologies of acquired laryngeal stenosis

Causes of Acquired Laryngeal Stenosis

• TRAUMA– External laryngeal trauma (adults more common)– Internal laryngeal trauma

• ~90% ETT related

• 0.9-8.3% incidence of laryngeal stenosis after intubation

• Chronic infection

• Chronic inflammatory dz

• Laryngeal neoplasm

5. Discuss the different types of laryngeal stenosis

Types of Laryngeal Stenosis

• Anterior

• Posterior

• Circumferential

• Complete

Posterior Glottic Stenosis

• Types I-IV

6. Discuss the endoscopic management of glottic and subglottic stenosis. What are

the contraindications to endoscopic management.

Endoscopic Dilation

• Sometimes useful early in the development of stenosis

• Not recommended for mature, firm stenosis or cartilaginous stenosis

• Bougie or balloon

• Corticosteroids (systemic, local, inhalational, topical)

• Mitomycin C

Endoscopic CO2 Laser Scar Excision

• Vaporize scar tissue with precision, producing minimal damage to healthy areas

• Useful for managing early stenosis with granulation tissue

• May be used in conjunction with dilation

• May require multiple procedures

Situations in which Endoscopic Management Less Successful

• Circumferential cicatricial scarring• Abundant scar tissue greater than 1 cm in vertical dimension• Fibrotic scar tissue in the interarytenoid area of the posterior

commissure• Severe bacterial infection of the trachea after tracheotomy• Exposure of perichondrium or cartilage during CO2 excision,

predisposing to perichondritis and chondritis• Combined laryngotracheal stenosis• Failure of previous endoscopic procedures• Significant loss of cartilaginous framework

7. When and how do you do a cricoid split? List the criteria for cricoid split.

Cricoid Split

Cricoid Split

• Described in 1980 (Cotton & Seid, Ann Otol Rhinol Laryngol) as an alternative to tracheotomy in the management of acquired SGS in premature infants

• Safe and effective (67-70% extubation rate) – If stenosis isolated & moderate grade– No other anatomic abnormalities prohibiting

decannulation– Pulmonary reserve must be adequate

8. You are consulted on a difficult to extubate neonate with subglottic stenosis. The family

refuses a tracheostomy because they have heard of the high incidence of M&M in this

population. What other options do they have

(medical and surgical)?

9. Describe the open surgical management of posterior glottic

stenosis in children.

Posterior Cricoid Graft

The Use of Posterior Cricoid Grafting in Managing Isolated Posterior Glottic

Stenosis in Children

• Retrospective review, 12yrs

• 29 patients

• Overall decannulation rate 97%

Rutter, Cotton; Arch Otolaryngol Head Neck Surg 2004;130:137-139.

10. Discuss the pros and cons of single stage laryngotracheal reconstruction.

Single Stage LTR

• Surgical correction of the stenotic airway with a short period of endotracheal intubation

• Avoids prolonged laryngotracheal stenting and trach tube dependence

Single Stage Laryngotracheal Reconstruction in Children

• Retrospective review, 11 yrs, 200 SSLTRs• 29% required reintubation, 52% of those required postop

trach, and 4% still trach dependent• Overall success 96%• Higher reintubation/trach rate for anterior + post. grafts• Children < 4yrs more reintubations• Leak pressure <20cm H2O, ↑ success• Mod. to severe tracheomalacia relative contraindication to

SSLTR

Gustafson et al. Otolaryngol Head Neck Surg 2000;123:430.

11. To stent or not to stent.

SSLTR Without Stenting• Retrospective review, 2 yrs, 21 patients• Anterior rib graft with immediate extubation• Grade II – III SGS• 90% successfully extubated immediately, 95%

successfully extubated within 48hrs• “Proper patient selection is essential…

procedure not applicable for severe stenosis or cases requiring anterior + post. grafts

Younis, Lazar. Otolaryngol Head Neck Surg 2000;122:488.

Effect of Stenting after LTR in a SGS Model

• Prospective, animal study• SGS created in 42 rabbits• All received LTR after 3 weeks• ½ received intraluminal stent• 4 stented & 4 unstented animals euthanized on POD#

6, 9, 14, 21, and 28• Increased vascularity in stented group on POD 6-14• Trend toward ↑ edema and granulation in stented

group on POD 21 & 28

Jewett, et al. Otolaryngol Head Neck Surg 1997;116:358.

12. List important factors in prevention of laryngotracheal stenosis.

Gatroesophageal Reflux: A Critical Factor in Pediatric SGS

• Retrospective review, 5yrs, 25 pts with SGS• Cotton Grades I-III• All received double pH probe study and “aggressive

preop GER Tx”• 9 pts avoided surgical tx• 16 pts underwent endoscopic repair, with one failure• “Aggressive preop management of GER led to a drop

in endoscopic repair failures from 1:5.7 to 1:25”Halstead. Otolaryngol Head Neck Surg 1999;120:683.

13. Discuss the proper assessment for decannulation in the pediatric

population.

Pediatric Decannulation• Tracheotomy tube is gradually downsized and

eventually plugged

• Continuous adult supervision and O2 sat monitoring

• Endoscopy should be performed to ensure the airway is clear

• Suprastomal granulomas should be removed

• Fenestration?

14. What is the data on Mitomycin C and prevention of restenosis?

Mitomycin

• Antineoplastic antibiotic derived from Streptomyces caespitosus

• Alkylating agent to inhibit DNA synthesis as well as to inhibit cell division and fibroblast proliferation

• Several single-arm studies (Ward 1998, Rahbar 2000) show benefit in reducing restenosis

• Several double-arm animal studies (Eliashar 1999, Correa 1999, Spector 1999) show clear benefit of topical mitomycin in reducing SGS in dogs

Topical Mitomycin Application after LTR

• Randomized, double blind, placebo-controlled trial

• One time application of Mitomycin (n=13) or placebo (n=11) at extubation/stent removal following LTR

• Degree of granulation graded by endoscopy at 2wks, 6wks, and 3mo

• No difference between Mitomycin and placeboHartnick et al. Ann Otol Laryngol 2001;110:1.

15. Identify complications related to airway management in children.

Airway Management of Children Requiring ET Intubation Prior to ICU

• Prospective, descriptive, multicentered study of children requiring ET intubation prior to ICU admission, N=250

• Only 26% pts <1y received antcholinergic prior to intubation

• 4% received paralysis without sedation• Most variances occurred in pts <1y old• Only 65% received CXR post intubation• Wrong ETT size used in 16% of patients

Easley et al. Crit Care Med 2000;28:2058-2063.

16. Discuss the proper antimicrobial coverage in laryngotracheal stents.

Microbiology of Stents in LTR

• Prospective study, 8yrs, n=21• Stents sent for cx immediately following removal• All stents had more than one pathogen• Strep viridans, Pseudomonas aeruginosa, Staph

aureus, Haemophilus influenza, Neisseria spp• 26% of stents had anaerobes• 57% of stents had Candida spp.• Consideration of broader Abx coverage is warranted

to reduce granulation

Simoni, Wiatrak. Laryngoscope 2004;114:364-367.