International Journal of Pediatric Otorhinolaryngology 73 (2009) 981–985

Partial cricotracheal resection for congenital subglottic stenosis in children: Theeffect of concomitant anomalies

Mercy George, Christos Ikonomidis, Yves Jaquet, Philippe Monnier *

Department of Otolaryngology, Head and Neck Surgery, University Hospital (CHUV), Lausanne, Vaud, Switzerland 1011, Switzerland

A R T I C L E I N F O

Article history:

Received 2 December 2008

Received in revised form 4 February 2009

Accepted 21 March 2009

Available online 17 May 2009

Keywords:

Cricotracheal resection

Congenital subglottic stenosis

Congenital anomalies

Syndromic anomalies

A B S T R A C T

Objective: To review the surgical outcomes of partial cricotracheal resection in children with severe

congenital subglottic stenosis and define the effect of concomitant anomalies or syndromes affecting

outcome.

Methods: Forty-one children with subglottic stenosis of congenital and mixed (acquired on congenital)

etiologies who underwent partial cricotracheal resection were identified from a prospectively collected

database. Children with congenital subglottic stenosis and concomitant anomalies/syndromes were

compared to children with congenital subglottic stenosis with no syndromes or concomitant anomalies.

Operation-specific decannulation rates and complication rates were the primary outcome measures. We

performed a two-sample test of proportion using the STATA-10 software for categorical variables to

detect differences in proportions. Significance was set at p value < 0.05.

Results: Twenty-seven (66%) of 41 children had concomitant anomalies/syndromes and 14 (34%) had

congenital subglottic stenosis without concomitant anomalies/syndromes. Four patients needed

revision surgery in the concomitant anomaly group and two patients needed revision surgery in the non

concomitant anomaly group before achieving decannulation. The operation-specific decannulation rate

in the concomitant anomaly group was 85% and 86% in the non anomaly group. When compared to

children without concomitant anomaly, children with concomitant anomalies were more likely to have

delayed decannulation following partial cricotracheal resection. However, this difference was not found

to be statistically significant. The complication and operation-specific decannulation rates after partial

cricotracheal resection were comparable to children without concomitant anomalies. Mortality rate was

11% (three of 27 patients) in the group with associated congenital anomalies or syndromes. Two patients

succumbed to the primary pathology and one patient died due to tracheostomy-tube obstruction. There

was no post-operative death in the non anomaly group.

Conclusion: Partial cricotracheal resection can be done safely and effectively in children with

concomitant anomalies/syndromes to achieve decannulation. The post-operative course may be

prolonged but the decannulation and the complication rates are comparable to those children with

congenital subglottic stenosis without concomitant anomalies.

� 2009 Elsevier Ireland Ltd. All rights reserved.

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1. Introduction

Congenital subglottic stenosis (SGS) is the third most commoncongenital laryngeal anomaly after laryngomalacia and vocal cordparalysis [1]. This is also the most common laryngeal anomalynecessitating tracheostomy in children less than 1 year of age [2].Subglottic stenosis can be classified into congenital, mixed oracquired types. In congenital stenosis, the patient will present withsymptoms of respiratory obstruction with no other contributing

* Corresponding author at: Chef de Service, Department of Otolaryngology Head

and Neck Surgery, Centre Hospitalier Universitaire Vaudois, Lausanne 1011,

Switzerland. Tel.: +41 21 3142700; fax: +41 21 3142607.

E-mail address: philippe.monnier@chuv.ch (P. Monnier).

0165-5876/$ – see front matter � 2009 Elsevier Ireland Ltd. All rights reserved.

doi:10.1016/j.ijporl.2009.03.023

factors. Mixed subglottic stenosis implies that a child born with anarrow but asymptomatic subglottic airway becomes sympto-matic after a history of endotracheal intubation (acquired oncongenital). The true incidence of congenital subglottic stenosis isdifficult to assess due to the high incidence of intubation inpatients with pre-existing narrow subglottic airway. The presenceof subglottic pathology should be looked for in a child with geneticsyndromes or other non-syndromic congenital anomalies, espe-cially when these involve the mediastinum (cardiovascular oresophageal anomalies).

The choice between laryngotracheal reconstruction (LTR) andpartial cricotracheal resection (PCTR) depends on the severity andextent of the subglottic stenosis as well as the vocal cord function.In severe established cases of congenital or acquired subglotticstenosis, partial cricotracheal resection has emerged as a better

Fig. 1. (A) Pre-operative endoscopic image of a 14-year old patient with Down syndrome showing Grade III acquired on congenital subglottic stenosis with interarytenoid

fibrosis. This patient had prior surgical intervention which included LTR, laser, and endoscopic dilatations before coming to our hospital. (B) Post-operative endoscopic image

2.5 months after PCTR with interarytenoid scar excision showing satisfactory airway.

M. George et al. / International Journal of Pediatric Otorhinolaryngology 73 (2009) 981–985982

surgical option than laryngotracheal reconstruction with noadverse effect on the post-operative growth of the pediatriclarynx. Decannulation has been achieved in a higher percentage ofpatients with a single operation for severe SGS (grade III and IV)following PCTR when compared to LTR [3–5]. In this manuscript,we compare the outcome in a cohort of patients with severecongenital SGS and associated concomitant anomalies to anothergroup of children with severe congenital SGS without concomitantanomalies who underwent PCTR. We also draw attention to thevarious syndromes associated with congenital SGS and theirinfluence on the prognosis and outcome following PCTR (Figs. 1and 2).

2. Methods

Over a 30-year period (1978–2008), there were 104 pediatriccricotracheal resections undertaken for pediatric laryngotrachealstenosis (LTS) at the University Hospital, Lausanne, Switzerland. Adatabase of all patients who have undergone PCTR has beenmaintained prospectively from 1978 to 2008.The institutionalreview board at Lausanne university hospital (CHUV) approved thereview of patients who had undergone PCTR for this study. Aretrospective chart review was carried out to identify children who

Fig. 2. (A) Pre-operative endoscopic image of an 18 months old child with acquired on

operative endoscopic image 4 years after primary PCTR and separation of fused vocal co

could be extubated 1 week after surgery.

had undergone PCTR for congenital or mixed (acquired oncongenital) subglottic stenosis. The details of the patients’ medicalhistories were extracted with special attention to the variousconcomitant anomalies/syndromes associated with the stenosis,the age of the patients, the grading of stenosis, time todecannulation and complications. The operation-specific decan-nulation rates for the groups were also calculated.

3. Results

Forty-one children who underwent PCTR for congenital ormixed stenosis formed the focus of this study. There were 27children with associated syndromes or congenital anomalies.They were compared to the 14 children with no concomitantanomalies or syndromes. The cricoid cartilage was elliptical in 30and small in seven patients. Laryngeal atresia was present in fourpatients. Thirty-four (83%) of 41 patients had severe grade IIIstenosis and seven (17%) patients had grade IV stenosis in thegroup of mixed etiology. The presence of glotto-subglotticstenosis (G-SGS) was seen in eight patients (30%) in theconcomitant anomaly group and in three (21%) in the nonanomaly group. The characteristics of the 41 patients aredescribed in Table 1.

congenital glotto-subglottic stenosis and associated Catch 22 syndrome. (B) Post-

rds, showing satisfactory airway. This patient underwent single-stage PCTR and he

Table 1Comparative profile of children with concomitant anomalies vs. children without

concomitant anomalies.

Congenital SGS and

concomitant anomalies

Congenital SGS without

concomitant anomalies

Number (total) 27 (66%) 14 (34%)

Age (range) 2 months to 14 years 3 months to 12 years

Age (�2 years) 9 5

Tracheostomy 23 (85%) 11 (79%)

G-SGS 8 (30%) 3 (21%)

Salvage surgery 8 (30%) 6 (43%)

Single-stage 18 (67%) 10 (71%)

Grade III 22 (81%) 12 (86%)

Grade IV 5 (19%) 2 (14%)

Revision open surgery 4 (15%) 2 (14%)

Operation-specific

decannulation rate

85% 86%

Follow up >2 years 12 9

Table 2Associated syndromes/anomalies.

Syndrome/anomalies No

Catch 22 2

Keutel syndrome 1

Fraser syndrome 1

Spondylo-epiphyseal dysplasia 1

Vater syndrome 1

Down syndrome 3

Aperts syndrome 1

Beals syndrome 1

Laryngomalacia, hemi-facial microsomia, mental retardation 1

Esophageal atresia 5

Tracheo-esophageal fistula 3

Bronchus suis 2

Cardiac anomalies 5

M. George et al. / International Journal of Pediatric Otorhinolaryngology 73 (2009) 981–985 983

3.1. Congenital subglottic stenosis with concomitant anomalies/

syndromes

There were 27 patients in this group with concomitantcongenital anomalies or syndromic association. They were anaverage age of 50 months (range, 2 months to 14 years, median= 34 months). The various syndromes and concomitant anomaliesincluded Catch 22 syndrome (n = 2), Keutel syndrome (n = 1),Fraser syndrome (n = 1), spondylo-epiphyseal dysplasia (n = 1),Vater syndrome (n = 1), Down syndrome (n = 3), Aperts syndrome(n = 1), Beals syndrome (n = 1), craniofacial anomaly with lar-yngomalacia and mental retardation (n = 1), esophageal atresia(n = 5), tracheo-esophageal fistula (n = 3), right tracheal bronchus(bronchus suis, n = 2) and congenital cardiac anomalies (n = 5)(Table 2).The average time of extubation/decannulation was 4.8months (range, 4 days to 34 months, median = 1 month). Thesingle-stage surgery category was 67% (18 of 27 patients) in theconcomitant anomalies group and 71% (10 of 14 patients) in thenon anomaly group. The average time of extubation in patientswho underwent single-stage surgery was 9 days (median = 7 days)and the average time in the double-stage surgery group was 14months (median = 10 months). Three patients died post-opera-

Table 3Revision open surgery in subglottic stenosis with concomitant anomalies.

Age (months/years) Cause Revision surgery

2 months PGS LTR

13 months Supraglottic stenosis Supraglottoplasty

28 months Re-stenosis PCTR

12 years PGS LTR

PGS: posterior glottic stenosis.

tively. One patient with Catch 22 syndrome died 6 weeks post-operatively due to aspiration and severe bronchospasm despite asatisfactory airway. One patient with spondylo-epiphyseal dys-plasia died due to respiratory insufficiency despite maintaining thetracheostomy cannula. Another child with laryngomalacia, mentalretardation, and hemi-facial microsomia died at home due totracheostomy-tube obstruction. Overall mortality in the conco-mitant anomalies group was 11%. All 24 remaining patients havebeen decannulated. Four patients in this series needed revisionopen surgery before achieving decannulation (15%). Two of fourpatients needed LTR for recurrent posterior glottic stenosis, onepatient needed supraglottoplasty and the last patient neededrevision PCTR for restenosis before decannulation could beachieved (Table 3). The operation-specific decannulation rate inthis group was 85% and the overall decannulation rate of thesurviving patients was 100%.

3.2. Congenital subglottic stenosis without concomitant anomalies

The 14 patients with congenital subglottic stenosis withoutconcomitant anomalies had the following characteristics. Themean age was 44 months (range, 3 months to 12 years;median = 29 months). Five children were less than 2 years ofage. Eleven of 14 patients were tracheotomized. Most underwent asingle-stage operation (n = 11). The average time of extubation/decannulation was 2.14 months (range, 5 days to 20 months). Theaverage time of extubation in the single-stage surgery group was 8days (median = 7 days). The average time of decannulation in thedouble-stage surgery group was 9 months (median = 7 months).All patients in this group could be decannulated, but two patients(14%) needed revision surgery (posterior cricoid split with costalcartilage graft in one patient for posterior glottic stenosis andrevision PCTR for restenosis in another patient) before decannula-tion. Therefore, the operation-specific decannulation rate was 86%and the overall decannulation rate 100%. There was no post-operative death in this group of congenital subglottic stenosiswithout concomitant anomalies.

3.3. Long-term follow up

All of the surviving 38 patients in this series have beendecannulated. The overall decannulation rate was 95% (39 of 41patients) and the overall operation-specific decannulation rate was85% (35 of 41 patients) in this series of 41 patients. The medianlong-term follow-up period was 5 years (range, 1–23 years). Thelaryngotracheal development was found to be normal in thechildren who reached adulthood. Normal breathing was seen in 31patients, seven patients showed some exertional dyspnoea. Voicepost-operatively was normal or near normal in 11 of 38 (29%)patients. Seventeen (45%) patients had mild dysphonia (roughvoice with difficulties being heard in loud environments) and eightpatients had weak, whispering voice. Two patients complained ofmarked dysphonia due to scarring of the vocal cords. We noticedthat the initial vocal cord pathology influenced the final post-operative voice quality in the acquired on congenital SGS group.Swallowing was normal in 36 patients and two patients hadoccasional coughing during meals due to mild aspiration.

Co-morbidity Decannulation

Laryngeal cleft, cardiac anomalies 23 months

Beals syndrome/hypoplastic mandible 32 months

Tracheal bronchus 34 months

Keutel syndrome 11 months

M. George et al. / International Journal of Pediatric Otorhinolaryngology 73 (2009) 981–985984

3.4. Statistical analysis

The group of children with concomitant anomalies wascompared to a group of children without concomitant anomalies.The pre-operative variables analyzed included age, severity ofstenosis, pre-operative tracheostomy, salvage surgery and single/double-stage surgery. Time to decannulation, complications andoperation-specific decannulation rates were the outcome mea-sures used for the two groups. Data analysis was done using STATAsoftware. Differences between study groups with respect tocategorical variables were studied using a two-sample test ofproportion. Chi square test was also used to analyze the effect ofthese variables on the outcome measures in the two groups.Significance was set at a p value less than 0.05 and the confidenceintervals were ascertained for each parameter. None of the pre-operative variables were found to have a statistically significanteffect on the outcome measures between the two groups.

4. Discussion

Congenital subglottic stenosis can present at birth or maybecome symptomatic across a variety of ages. The diagnosis ofsubglottic stenosis is made when the luminal diameter is less than4 mm at birth in a full-term infant and 3 mm in a premature infant.Congenital SGS may be soft-tissue stenosis or cartilaginous. In soft-tissue stenosis, submucosal gland hyperplasia and fibrosis areseen. In the cartilaginous type of congenital SGS, a small normallyshaped cricoid cartilage or an abnormally shaped cricoid is seen.Tucker et al. first described the elliptical cricoid cartilage, which isthe most frequently encountered abnormal shape that causescongenital subglottic stenosis [2]. In our series of 41 patients, theelliptical cricoid was seen in the majority (73%), similar todescriptions in the literature.

The diagnosis of congenital SGS is to be considered in a childwith recurrent croup under the age of 1 year [6]. The managementis based on the grading and the severity of the stenosis. Severecases of congenital subglottic stenosis may require PCTR, which istechnically demanding but is of paramount importance when weconsider the advantages of early decannulation. The reportedmortality in the literature directly related to the tracheostomy is2–3% [7,8]. Tube occlusion, accidental decannulation and thechild’s residual airway above the tracheostomy are the factorsrelated to the mortality of tracheostomy [9]. We also had one post-operative death secondary to tracheostomy-tube obstruction. Inaddition, tracheostomy in a child prevents phonation and therebydelays communicative skills. Therefore, the ‘‘wait-and-see’’approach in a child with severe subglottic stenosis is not justifiable.Age also should not be a limiting factor for a definite surgicalprocedure. The youngest patient in our series was 2 months old.Twelve (29%) of the 41 children were 1 year or less. Johnson et al.have described PCTR as a safe and efficacious method of airwayreconstruction in children with SGS who were 2 years or younger.The overall decannulation in their series of 15 children was 87%[10].

4.1. Concomitant anomalies/syndromic associations

The evaluation of a child with congenital subglottic stenosisinvolves a complete medical history and physical examination tolook for any concomitant anomalies. For instance, children withDown syndrome have a high incidence of congenital airwaystenosis [11]. Three patients in our series had Down syndrome. Thebest results with such patients can only be achieved by amultidisciplinary team effort, which becomes the cornerstonefor overall success. Shott has suggested that initial intubation in achild with Down syndrome should be performed with an

endotracheal tube at least two sizes smaller than would be usedin a normal child of the same age to avoid trauma to the airway[12]. These children, due to the hyperflexibility of the neck will beat increased risk of anastomotic dehiscence after cricotrachealresection for subglottic stenosis. Alarcon and Rutter havesuggested maintaining chin-to-chest sutures for at least 2 weeksafter PCTR to reduce the risk of dehiscence in children with Downsyndrome [13]. In our series, we did not use chin-to-chest suturespost-operatively and our patients did not develop anastomoticdehiscence. Congenital laryngeal atresia was found in four patientsin our series. Recently, the survival rate in laryngeal atresia hasimproved due to prenatal diagnosis of this condition, which allowselective tracheotomy under fetal circulation to be performed [14].

Tracheal bronchus, seen in two of four patients in this series, isan unusual congenital anomaly in which the right upper lobe hasits origin most often from the right tracheal wall above the carina.Tracheal bronchus may be associated with other bronchopulmon-ary anomalies, long segment tracheal stenosis with circular ringsor Down syndrome. Children with tracheal bronchus usuallypresent with stridor, cough, and recurrent pneumonia. Thepediatric otolaryngologist should be aware of the possibility ofsubglottic/tracheal narrowing in children with tracheal bronchus[15].

The association of subglottic stenosis and Fraser syndrome hasbeen described in literature. Fraser syndrome is a rare autosomalrecessive disorder characterized by cryptophthalmos, externalauditory meatal stenosis, choanal atresia, laryngeal atresia orstenosis. Ford et al. described four patients with Fraser syndromeassociated with subglottic stenosis [16]. The diagnosis of subglotticstenosis was made in three patients at the time of intubation forother reconstructive procedures. The child with Fraser syndromein our series was referred with severe stridor due to glotto-subglottic stenosis. PCTR and separation of fused vocal cords weredone, and the child could be extubated on the 8th post-operativeday with a good airway.

Meier et al. have described two patients with Keutel syndromeand associated tracheobronchial stenosis. This syndrome, firstdescribed by Keutel in 1971, is a rare disorder presenting withperipheral pulmonary stenosis, neural hearing loss and abnormalcartilage calcification [17,18]. Buchsteiner et al. have reportedsubglottic stenosis in two brothers with Keutel syndrome at theages of 14 and 21 years, leading to emergency tracheostomy [19].Our patient with Keutel syndrome who presented to us with atracheostomy also had a calcified and hypoplastic larynx, trachea,and bronchi. This patient needed revision surgery (LTR) forposterior glottic stenosis after 5 months of primary PCTR, butwith a good outcome. To prevent anesthetic complications,patients with Keutel syndrome should be assessed for impairmentof lung function pre-operatively.

Vater syndrome, which is characterized by vertebral, anorectal,and tracheo-esophageal defects, can have additional manifestationof subglottic stenosis as described by Corsello et al. [20]. Ourpatient with Vater syndrome had associated esophageal atresiaand tracheo-esophageal fistula. A single-stage PCTR was per-formed in this patient with a good outcome.

Early deaths have been reported in patients with Apertsyndrome secondary to both upper and lower airway compromise.Possible mechanisms are tracheal stenosis and/or tracheal rigiditywith resultant respiratory insufficiency [21]. Our patient withApert syndrome did not need prolonged ventilation and could beextubated within a week.

Two patients in our series had Catch 22 syndrome, which isassociated with a deletion within chromosome 22q11. Theimportant features of this syndrome are cardiac defects, abnormalfacial features, thymic hypoplasia, cleft palate, and hypocalcaemia.It also includes DiGeorge syndrome, conotruncal anomaly face

Table 4Time to decannulation.

Decannulation in months SGS with concomitant

anomalies (no = 27)

Isolated SGS

(no = 14)

�1 15 (56%) 11 (79%)

1–6 4 1

6–12 2 1

12–24 1 1

>24 2 0

Died 3 0

M. George et al. / International Journal of Pediatric Otorhinolaryngology 73 (2009) 981–985 985

syndrome and velocardiofacial syndrome [22]. Laryngotrachealstenosis usually presents as a web at the vocal cords extending onto the subglottis. Although it is not a common finding in thisdisease, its presence will have a significant effect on the manage-ment of these patients. One patient with Catch 22 syndrome died 6weeks post-operatively due to aspiration and severe bronchos-pasm. Visualization of the airway during spontaneous respirationis indicated in any patient with Catch 22/DiGeorge syndrome todiagnose structural abnormalities of the larynx and trachea.

The one child with Beals syndrome in our series had acongenitally small cricoid. This is an extremely rare geneticdisorder characterized by arachnodactyly, camptodactyly, kyphos-coliosis, ectopia lentis, and mitral valve prolapse [23]. Theassociation of subglottic stenosis in Beals syndrome is rarelyreported in the literature. This patient needed supraglottoplasty asa second procedure for the correction of the supraglottic stenosisafter primary PCTR with a satisfactory result. This patient alsorequired a distraction osteogenesis of the lower jaw for ahypoplastic mandible before achieving decannulation.

One patient who died post-operatively due to respiratoryinsufficiency had associated congenital spondylo-epiphysealdysplasia (SED). SED is caused by mutations in COL2A1 (type IIcollagen alpha 1 chain) on chromosome 12 [24]. Prior to anysurgical intervention in patients with SED, special attention shouldbe given to odontoid hypoplasia, short and unstable neck,decreased pulmonary functions due to thoracic cage malforma-tions and rigid spinal deformities. Our patient died 10 monthspost-operatively due to poor pulmonary reserve secondary tothoracic cage malformation.

Operation-specific decannulation, signifying no need for anextra open procedure, occurred in 35 patients in our series (85%).Posterior glottic stenosis (PGS) was the reason for revision surgeryin three of six patients who needed a second procedure to bedecannulated. White et al. have reported the need of a second openprocedure in 12 of 21 patients who underwent PCTR when vocalcord dysfunction was present pre-operatively [25].

Selection of the properly sized ETT is important in case ofintubation to avoid injury to the subglottis in children withexpected subglottic narrowing. Awareness among the medicalcommunity should help surgeons minimize unnecessary damageto the trachea by placing the tracheostomy-tube as close to thestenosis as possible in an established case of SGS. This avoidsresection of a long segment of the trachea, thereby reducingtension at the anastomotic site. We believe that a double-stageprocedure is certainly preferable in children with concomitantanomalies as most of them will have inadequate cardiopulmonaryreserve. Delayed closure of the tracheostomy, therefore, isjustifiable in these children to help pulmonary toileting and toavoid major post-operative complications. Parents should becounseled that delay in decannulation may be expected whencricotracheal resection is performed in children with associatedcongenital anomalies (Table 4).

5. Conclusion

Our experience in this cohort of children with concomitantanomalies or syndromes provides ample proof that PCTR can beperformed safely and effectively with good outcome in themajority of the patients. With detailed and comprehensive pre-operative evaluation, decannulation, and complication in thisgroup of patients are comparable to those children with isolatedstenosis. Delay in decannulation is expected in children withconcomitant anomalies due to the poor cardiopulmonary reserve.A genetic consultation and karyotyping should be included inchildren with congenital subglottic stenosis to identify associatedsyndromes.

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