Endoscopic treatment of subglottic stenosis with flexible bronchoscopy via laryngeal mask airway

OBJECTIVE

To evaluate the safety and efficacy of endoscopic treatment of subglottic stenosis with flexible bronchoscopy via laryngeal mask airway (LMA) approach.

METHODS

The records of all patients who underwent endoscopic surgery for subglottic stenosis (SGS) from November 2019 to January 2023 at an academic medical center were reviewed with attention to demographics, patient comorbidities, airway stenosis characteristics, operative time details, surgical complications, and post-operative course. All patients, >18 years old, with one or more surgeries for SGS using (LMA) for intraoperative airway management were included. Surgeries with suspension microlaryngoscopy were excluded. Patients with glottic stenosis or tracheotomy were excluded.

RESULTS

Thirty-five patients underwent 52 procedures meeting inclusion criteria. Mean age was 55 years (range 31-78, SD 13.3) and 33 patients (94%) were female. Mean BMI was 30.9 (range 18.4-60.5, SD 8.8). The most common etiology of stenosis was intubation injury in 17 patients (49%), followed by idiopathic in 13 patients (37%). Cotton-Meyer grade 3 (71-99% narrowing) was seen in 25 patients (71%). Mean anesthesia and surgical operative times were 75.9 min (SD 13.5 min) and 39.7 min (SD 11.0 min), respectively. Mean SpO2 nadir was 94.5% (SD 6.3%). No patients required intraoperative change to rigid laryngoscopy, intubation, or tracheotomy. There were no post-operative complications. Mean surgery-free interval was 12.2 months (SD 6.3).

CONCLUSION

Endoscopic treatment of subglottic stenosis with flexible bronchoscopy and spontaneous ventilation via LMA approach is a safe and effective option, especially in patients with limitations for rigid laryngoscopy and elevated BMI.

LEVEL OF EVIDENCE

Level Four (case series) Laryngoscope, 134:2672-2677, 2024.

How can we identify subglottic stenosis in patients with suspected obstructive disease?

PURPOSE

Subglottic stenosis, a rare condition of the upper airway, is frequently misdiagnosed as obstructive lung disease. The aim of this study was to investigate whether subglottic stenosis could be identified and distinguished from asthma and chronic obstructive pulmonary disease (COPD) using spirometry or the dyspnea index (DI).

METHODS

The study population included 43 patients with asthma, 31 patients with COPD and 50 patients with subglottic stenosis planned to undergo endoscopic intervention. All patients completed the DI and underwent dynamic spirometry registering both inspiratory and expiratory volumes and flows, including the expiratory disproportion index (EDI), the ratio of forced expiratory volume in 1 s to peak expiratory flow. One-way analysis of variance assessed the discrepancy of the variables among the study groups, and receiver operating curve (ROC) analysis determined the measurement with the best discriminatory power providing a cutoff value, maximizing both sensitivity and specificity.

RESULTS

The only statistically significant variables differing between all three groups were the EDI and the DI. The EDI showed an excellent area under the ROC curve (0.99, p < 0.001) with a cutoff value of 0.39 (98% sensitivity, 96% specificity), followed by DI (0.87, p < 0.001) with a cutoff score of > 25 (83% sensitivity and 78% specificity).

CONCLUSION

In patients with dyspnea of unknown cause, an increase in EDI should arouse a suspicion of extrathoracic airway obstruction, advocating for further evaluation with laryngotracheoscopy.

Mapping Genetic Susceptibility to Stenosis in the Proximal Airway

OBJECTIVES

Recent translational scientific efforts in subglottic stenosis (SGS) support a disease model where epithelial alterations facilitate microbiome displacement, dysregulated immune activation, and localized fibrosis. Yet despite recent advances, the genetic basis of SGS remains poorly understood. We sought to identify candidate risk genes associated with an SGS phenotype, investigate their biological function, and identify the cell types enriched for their expression.

METHODS

The Online Mendelian Inheritance in Man (OMIM) database was queried for single gene variants associated with an SGS phenotype. The functional intersections and molecular roles of the identified genes were explored using pathway enrichment analysis (PEA) computational methods. Cellular localization of the candidate risk genes was measured via transcriptional quantification in an established single cell RNA sequencing (scRNA-seq) atlas of the proximal airway.

RESULTS

Twenty genes associated with SGS phenotype were identified. PEA resulted in 24 significantly enriched terms including "cellular response to TGF-β," "epithelial-to-mesenchymal transition," and "adherens junctions." Mapping the 20 candidate risk genes to the scRNA-seq atlas found 3 (15%) genes were enriched in epithelial cells, 3 (15%) in fibroblasts, and 3 (15%) in endothelial cells. 11 (55%) genes were expressed ubiquitously among tissue types. Interestingly, immune cells were not significantly enriched for candidate risk genes.

CONCLUSION

We identify and provide biologic context for 20 genes associated with fibrotic disease of the proximal airway and form the foundation for future detailed genetic study.

LEVEL OF EVIDENCE

N/A Laryngoscope, 133:3049-3056, 2023.

Serial In-Office Steroid Injections for Airway Stenosis: Long-Term Benefit and Cost Analysis

OBJECTIVES

To evaluate the long-term benefit of serial in-office steroid injections (SISI) in the treatment of subglottic and proximal tracheal stenosis (SG/PTS). Evaluate cost of SISI compared to endoscopic dilation (ED).

STUDY DESIGN

Retrospective study and cost analysis.

METHODS

All patients with SGS/PTS with at least two consecutive in-office steroid injections between 2013 and 2021 were evaluated. Patients with less than 2 years of follow-up data after the initial SISI series were excluded. Demographics, etiology of stenosis, total injections performed, time between steroid series, surgery-free interval (SFI) and adverse events were collected. For patients with known surgical history before SISI, pre-SISI SFI was compared. Institutional billing records and the national CMS average reimbursement were evaluated. Total charges for three treatment strategies (ED alone, ED with post-operative SISI and primary intervention with SISI) were also compared.

RESULTS

Forty-nine patients were included; 29 (59%) idiopathic, 11 (22%) traumatic and 9 (18%) rheumatologic. Mean (SD) follow-up time after the first SISI was 3.41 years (1.5), range (2.08-7.25 years). 79% (39/49) did not require additional surgery during the entire follow-up period. The SFI improved from a mean 13.5 months (SD 12.6; range 2-42 months) pre-SISI to a mean (SD) of 42 months (SD 20.2; range 10-87 months) (p < 0.0001) after SISI. Annual average charges for ED alone in our cohort was $15,383.28, compared to $7,070.04 for SISI.

CONCLUSIONS

SISI are an effective treatment for patients with SG/PTS. In-office steroid injections could offer cost savings for the patient.

LEVEL OF EVIDENCE

4 Laryngoscope, 133:2673-2679, 2023.

Tracheal microbiome and metabolome profiling in iatrogenic subglottic tracheal stenosis

BACKGROUND

To study the role of microecology and metabolism in iatrogenic tracheal injury and cicatricial stenosis, we investigated the tracheal microbiome and metabolome in patients with tracheal stenosis after endotracheal intubation.

METHODS

We collected 16 protected specimen brush (PSB) and 8 broncho-alveolar lavage (BAL) samples from 8 iatrogenic subglottic tracheal stenosis patients, including 8 PSB samples from tracheal scar sites, 8 PSB samples from scar-free sites and 8 BAL samples, by lavaging the subsegmental bronchi of the right-middle lobe. Metagenomic sequencing was performed to characterize the microbiome profiling of 16 PSB and 8 BAL samples. Untargeted metabolomics was performed in 6 PSB samples (3 from tracheal scar PSB and 3 from tracheal scar-free PSB) using high-performance liquid chromatography‒mass spectrometry (LC‒MS).

RESULTS

At the species level, the top four bacterial species were Neisseria subflava, Streptococcus oralis, Capnocytophaga gingivals, and Haemophilus aegyptius. The alpha and beta diversity among tracheal scar PSB, scar-free PSB and BAL samples were compared, and no significant differences were found. Untargeted metabolomics was performed in 6 PSB samples using LC‒MS, and only one statistically significant metabolite, carnitine, was identified. Pathway enrichment analysis of carnitine revealed significant enrichment in fatty acid oxidation.

CONCLUSION

Our study found that carnitine levels in tracheal scar tissue were significantly lower than those in scar-free tissue, which might be a new target for the prevention and treatment of iatrogenic tracheal stenosis in the future.

The diagnostic accuracy of spirometry as screening tool for adult patients with a benign subglottic stenosis

BACKGROUND

There is a considerable diagnostic delay in the diagnosis 'benign acquired subglottic stenosis in adults' (SGS, diagnosed by the reference standard, i.e. laryngo- or bronchoscopy). Patients are frequently misdiagnosed since symptoms of this rare disease may mimic symptoms of 'asthma.' The 'Expiratory Disproportion Index' (EDI) obtained by spirometry, may be a simple instrument to detect an SGS-patient. The aim of this study was to evaluate the diagnostic accuracy of the EDI in differentiating SGS patients from asthma patients.

METHODS

We calculated the EDI from spirometry results of all SGS-patients in the Leiden University Medical Center (LUMC), who had not received treatment 2 years before their spirometry examination. We compared these EDI results with the EDI results of all true asthma patients between 2011 and 2019, who underwent a bronchoscopy (exclusion of SGS by laryngo- or bronchoscopy).

RESULTS

Fifty patients with SGS and 32 true asthma patients were included. Median and IQR ranges of the EDI for SGS and asthma patients were 67.10 (54.33-79.18) and 37.94 (32.41-44.63), respectively. Area under the curve (ROC) of the accuracy of the EDI at discriminating SGS and asthma patients was 0.92 (95% CI = 0.86-0.98). The best cut-off point for the EDI was > 48 (i.e. possible upper airway obstruction), with a sensitivity of 88.0%% (95%CI = 77.2-95.0%%) and specificity of 84.4% (95%CI = 69.4-94.1%).

CONCLUSIONS

The EDI has a good diagnostic accuracy discriminating subglottic stenosis patients from asthma patients, when compared to the reference standard. This measurement from spirometry may potentially shorten the diagnostic delay of SGS patients. Further studies are needed to evaluate clinical reproducibility.

Idiopathic subglottic stenosis arises at the epithelial interface of host and pathogen

Background

Idiopathic subglottic stenosis (iSGS) is a rare fibrotic disease of the proximal airway affecting adult Caucasian women nearly exclusively. Life-threatening ventilatory obstruction occurs secondary to pernicious subglottic mucosal scar. Disease rarity and wide geographic patient distribution has previously limited substantive mechanistic investigation into iSGS pathogenesis.

Result

By harnessing pathogenic mucosa from an international iSGS patient cohort and single-cell RNA sequencing, we unbiasedly characterize the cell subsets in the proximal airway scar and detail their molecular phenotypes. Results show that the airway epithelium in iSGS patients is depleted of basal progenitor cells, and the residual epithelial cells acquire a mesenchymal phenotype. Observed displacement of bacteria beneath the lamina propria provides functional support for the molecular evidence of epithelial dysfunction. Matched tissue microbiomes support displacement of the native microbiome into the lamina propria of iSGS patients rather than disrupted bacterial community structure. However, animal models confirm that bacteria are necessary for pathologic proximal airway fibrosis and suggest an equally essential role for host adaptive immunity. Human samples from iSGS airway scar demonstrate adaptive immune activation in response to the proximal airway microbiome of both matched iSGS patients and healthy controls. Clinical outcome data from iSGS patients suggests surgical extirpation of airway scar and reconstitution with unaffected tracheal mucosa halts the progressive fibrosis.

Conclusion

Our data support an iSGS disease model where epithelial alterations facilitate microbiome displacement, dysregulated immune activation, and localized fibrosis. These results refine our understanding of iSGS and implicate shared pathogenic mechanisms with distal airway fibrotic diseases.

Balloon dilatation is superior to CO2 laser excision in the treatment of subglottic stenosis

INTRODUCTION

Endoscopic treatment of subglottic stenosis (SGS) is regarded as a safe procedure with rare complications and less morbidity than open surgery yet related with a high risk of recurrence. The abundance of techniques and adjuvant therapies complicates a comparison of the different surgical approaches. The primary aim of this study was to investigate disease recurrence after CO₂ laser excisions and balloon dilatation in patients with SGS and to identify potential confounding factors.

MATERIALS AND METHODS

In a tertiary referral center, two cohorts of previously undiagnosed patients treated for SGS were retrospectively reviewed and followed for 3 years. The CO₂ laser cohort (CLC) was recruited between 2006 and 2011, and the balloon dilatation cohort (BDC) between 2014 and 2019. Kaplan‒Meier and multivariable Cox regression analyzed time to repeated surgery and estimated hazard ratios (HRs) for different variables.

RESULTS

Nineteen patients were included in the CLC, and 31 in the BDC. The 1-year cumulative recurrence risk was 63.2% for the CLC compared with 12.9% for the BDC (HR 33.0, 95% CI 6.57-166, p < 0.001), and the 3-year recurrence risk was 73.7% for the CLC compared with 51.6% for the BDC (HR 8.02, 95% CI 2.39-26.9, p < 0.001). Recurrence was independently associated with overweight (HR 3.45, 95% CI 1.16-10.19, p = 0.025), obesity (HR 7.11, 95% CI 2.19-23.04, p = 0.001), and younger age at diagnosis (HR 8.18, 95% CI 1.43-46.82, p = 0.018).

CONCLUSION

CO₂ laser treatment is associated with an elevated risk for recurrence of SGS compared with balloon dilatation. Other risk factors include overweight, obesity, and a younger age at diagnosis.

Unanticipated Difficult Airway During Elective Surgery: A Case Report and Review of Literature

Difficult airway during anesthesia is responsible for several cases of morbidity and mortality worldwide, especially when it is unanticipated. Patients with either history of or with predictive factors of a difficult airway show better outcomes since all preventative measures will ensure patient safety. Approximately 30% of all deaths attributed to anesthesia are related to unsuccessful intubation. In this article, we discuss a patient who had a tracheostomy following an unanticipated difficult airway with undiagnosed subglottic stenosis and also reviewed the current literature on the difficult airway.

Laryngotracheal stenosis: Mechanistic review

Background

The purpose of this review article is to summarize the existing literature surrounding wound healing mechanisms in laryngotracheal stenosis.

Methods

A review of general wound healing pathophysiology, followed by a focused review of iatrogenic laryngotracheal stenosis (iLTS) and idiopathic subglottic stenosis (iSGS) as conditions of aberrant wound healing.

Results

iLTS is the scarring of the laryngotracheal complex, coming secondary to injury from prolonged intubation. iSGS is a chronic fibroinflammatory scarring and narrowing of the subglottic airway in the absence of any obvious preceding injury or trauma. They are both thought to result from a prolonged and dysregulated wound healing response that promotes the deposition of pathologic scar in the airway.

Conclusions

Understanding the mechanisms that underlie wound healing will help identify and intervene on the process early in its development and discover future therapies that target individual wound healing mechanisms limiting the incidence of this recalcitrant disease process.

Delayed Diagnosis of Idiopathic Subglottic Stenosis

OBJECTIVE

Idiopathic subglottic stenosis (iSGS) is a rare disease, causing life-threatening dyspnea secondary to scarring. Perhaps because it is rarely encountered, there is often a delay in diagnosing iSGS. The objective of this study is to characterize diagnostic delay of iSGS, factors that prolong delay, and its impact on iSGS patients.

STUDY DESIGN

Retrospective chart review.

METHODS

A retrospective chart review of 124 iSGS patients was performed. Times of symptom onset, presentation to otolaryngologist, diagnosis, imaging, pulmonary function testing (PFTs), surgeries, emergency department (ED) visits, and hospitalizations were recorded and univariate analyses were used to identify risk factors for delay.

RESULTS

The median total time to diagnosis from symptom onset was 24.5 months, with time to first presentation of 6.3 months and healthcare delay of 17.8 months. 54.8% of patients were diagnosed with asthma. Earlier presentation to otolaryngologist was associated with shorter healthcare delay and total time to diagnosis (rho = 0.75, rho = 0.99, P < .0001). Earlier CT imaging was correlated to shorter healthcare delay (rho = 0.84, P < .0001) and total time to diagnosis (rho = 0.74, P < .001), while earlier PFTs were correlated to shorter total time to diagnosis alone (rho = 0.71, P = .01). During evaluation, 10.5% (n = 17/124) of patients had ED visits and 13.7% (n = 13/124) patients were hospitalized. Before diagnosis, 7% (9/124) of patients underwent surgeries (including 3% (n = 4) undergoing tracheostomy) and 8% (n = 10) of patients required unplanned urgent endoscopic surgery that may have been avoided with earlier diagnosis.

CONCLUSION

iSGS diagnosis is frequently delayed, resulting in additional surgeries (including tracheostomy), ED visits, and hospitalizations. Further, patients' symptoms are commonly attributed to asthma. Earlier otolaryngologist evaluation, PFTs, and CT imaging may expedite iSGS diagnosis.

LEVEL OF EVIDENCE

4 Laryngoscope, 132:413-418, 2022.

The Proximal Airway Is a Reservoir for Adaptive Immunologic Memory in Idiopathic Subglottic Stenosis

OBJECTIVES/HYPOTHESIS

Characterization of the localized adaptive immune response in the airway scar of patients with idiopathic subglottic stenosis (iSGS).

STUDY DESIGN

Basic Science.

METHODS

Utilizing 36 patients with subglottic stenosis (25 idiopathic subglottic stenosis [iSGS], 10 iatrogenic post-intubation stenosis [iLTS], and one granulomatosis with polyangiitis [GPA]) we applied immunohistochemical and immunologic techniques coupled with RNA sequencing.

RESULTS

iSGS, iLTS, and GPA demonstrate a significant immune infiltrate in the subglottic scar consisting of adaptive cell subsets (T cells along with dendritic cells). Interrogation of T cell subtypes showed significantly more CD69+ CD103+ CD8+ tissue resident memory T cells (TRM ) in the iSGS airway scar than iLTS specimens (iSGS vs. iLTS; 50% vs. 28%, P = .0065). Additionally, subglottic CD8+ clones possessed T-cell receptor (TCR) sequences with known antigen specificity for viral and intracellular pathogens.

CONCLUSIONS

The human subglottis is significantly enriched for CD8+ tissue resident memory T cells in iSGS, which possess TCR sequences proven to recognize viral and intracellular pathogens. These results inform our understanding of iSGS, provide a direction for future discovery, and demonstrate immunologic function in the human proximal airway. Laryngoscope, 131:610-617, 2021.

Association of Social Determinants of Health with Time to Diagnosis and Treatment Outcomes in Idiopathic Subglottic Stenosis

OBJECTIVES

To examine whether social determinants of health (SDH) factors are associated with time to diagnosis, treatment selection, and time to recurrent surgical intervention in idiopathic subglottic stenosis (iSGS) patients.

METHODS

Adult patients with diagnosed iSGS were recruited prospectively (2015-2017) via clinical providers as part of the North American Airway Collaborative (NoAAC) and via an online iSGS support community on Facebook. Patient-specific SDH factors included highest educational attainment (self-reported), median household income (matched from home zip code via U.S. Census data), and number of close friends (self-reported) as a measure of social support. Main outcomes of interest were time to disease diagnosis (years from symptom onset), treatment selection (endoscopic dilation [ED] vs cricotracheal resection [CTR] vs endoscopic resection with adjuvant medical therapy [ERMT]), and time to recurrent surgical intervention (number of days from initial surgical procedure) as a surrogate for disease recurrence.

RESULTS

The total 810 participants were 98.5% female, 97.2% Caucasian, and had a median age of 50 years (IQR, 43-58). The cohort had a median household income of $62 307 (IQR, $50 345-$79 773), a median of 7 close friends (IQR, 4-10), and 64.7% of patients completed college or graduate school. Education, income, and number of friends were not associated with time to diagnosis via multivariable linear regression modeling. Univariable multinominal logistic regression demonstrated an association between education and income for selecting ED versus ERMT, but no associations were noted for CTR. No associations were noted for time to recurrent surgical procedure via Kaplan Meier modeling and Cox proportional hazards regression.

CONCLUSIONS

Patient education, income, and social support were not associated with time to diagnosis or time to disease recurrence. This suggests additional patient, procedure, or disease-specific factors contribute to the observed variations in iSGS surgical outcomes.

Comparative Treatment Outcomes for Patients With Idiopathic Subglottic Stenosis

Question

What are the outcomes of the 3 most common surgical approaches for idiopathic subglottic stenosis (iSGS)?

Findings

In this cohort study of 810 patients with iSGS who underwent 1 of the 3 most common surgical treatments, 23% of patients underwent a recurrent surgical procedure during the 3-year study period, but recurrence differed by modality (cricotracheal resection, 1%; endoscopic resection with adjuvant medical therapy, 12%; and endoscopic dilation, 28%). Among successfully treated patients, those who underwent cricotracheal resection reported the highest quality of life but the greatest perioperative risk and worst long-term voice outcomes.

Meaning

These results show the feasibility of integrating an engaged rare disease community with a network of surgeons to facilitate rapid and nuanced treatment comparisons; findings may help inform treatment decision-making in iSGS.

Importance

Surgical treatment comparisons in rare diseases are difficult secondary to the geographic distribution of patients. Fortunately, emerging technologies offer promise to reduce these barriers for research.

Objective

To prospectively compare the outcomes of the 3 most common surgical approaches for idiopathic subglottic stenosis (iSGS), a rare airway disease.

Design, Setting, and Participants

In this international, prospective, 3-year multicenter cohort study, 810 patients with untreated, newly diagnosed, or previously treated iSGS were enrolled after undergoing a surgical procedure (endoscopic dilation [ED], endoscopic resection with adjuvant medical therapy [ERMT], or cricotracheal resection [CTR]). Patients were recruited from clinician practices in the North American Airway Collaborative and an online iSGS community on Facebook.

Main Outcomes and Measures

The primary end point was days from initial surgical procedure to recurrent surgical procedure. Secondary end points included quality of life using the Clinical COPD (chronic obstructive pulmonary disease) Questionnaire (CCQ), Voice Handicap Index-10 (VHI-10), Eating Assessment Test-10 (EAT-10), the 12-Item Short-Form Version 2 (SF-12v2), and postoperative complications.

Results

Of 810 patients in this cohort, 798 (98.5%) were female and 787 (97.2%) were white, with a median age of 50 years (interquartile range, 43-58 years). Index surgical procedures were ED (n = 603; 74.4%), ERMT (n = 121; 14.9%), and CTR (n = 86; 10.6%). Overall, 185 patients (22.8%) had a recurrent surgical procedure during the 3-year study, but recurrence differed by modality (CTR, 1 patient [1.2%]; ERMT, 15 [12.4%]; and ED, 169 [28.0%]). Weighted, propensity score–matched, Cox proportional hazards regression models showed ED was inferior to ERMT (hazard ratio [HR], 3.16; 95% CI, 1.8-5.5). Among successfully treated patients without recurrence, those treated with CTR had the best CCQ (0.75 points) and SF-12v2 (54 points) scores and worst VHI-10 score (13 points) 360 days after enrollment as well as the greatest perioperative risk.

Conclusions and Relevance

In this cohort study of 810 patients with iSGS, endoscopic dilation, the most popular surgical approach for iSGS, was associated with a higher recurrence rate compared with other procedures. Cricotracheal resection offered the most durable results but showed the greatest perioperative risk and the worst long-term voice outcomes. Endoscopic resection with medical therapy was associated with better disease control compared with ED and had minimal association with vocal function. These results may be used to inform individual patient treatment decision-making.

Technique of laryngotracheal resection in subglottic stenosis

Cervical stenosis of the trachea caused by tracheotomy, tumor or induced by inflammatory disease can be treated by resection and anastomosis with good early and long-term results. Involvement of the ring cartilage makes the procedure technical demanding and increases the risk of morbidity. We describe our technique of laryngotracheal resection and reconstruction and compare the perioperative results with standard trachea resection. Between January 2005 and September 2018, we performed 92 standard cervical tracheal resections and 50 laryngotracheal resection including 6 procedures with widening of the ring cartilage. The resections were realized by direct anastomosis using dorsal flaps and/or interposition of rib cartilage in the posterior part of the ring cartilage. In one case intraoperative tracheotomy and intralaryngeal stenting was used. Patient records have been analyzed for perioperative data retrospectively. The main cause for stenosis or defect of the trachea and operation is preceding tracheotomy. Idiopathic stenosis, tumors and subglottic stenosis in Wegener disease are less common. Healing of the anastomosis was not disturbed in any patient. In two patients, bronchoscopic resection of granulation tissue was necessary. Tracheotomy in the course of treatment for intralaryngeal swelling or recurrent nerve palsy was necessary in 3 patients including one intraoperative tracheotomy for glottic stenting. Postoperative tracheostomy was closed in all patients within 3 months. Pulmonary complications and persistent recurrent nerve palsy occurred in 4 and 2 of the patients, respectively. Two patients died of pulmonary complications. The laryngotracheal resection is a relevant part of cervical tracheal surgery. It can be performed without significant elevated morbidity and is able to restore lung function and quality of voice.

Differing Progression to Posterior Glottic Stenosis in Autoimmune and Idiopathic Subglottic Stenosis

OBJECTIVES/HYPOTHESIS

We sought to characterize rates of progression to posterior glottic stenosis (PGS) from autoimmune or idiopathic subglottic stenosis.

STUDY DESIGN

This was a retrospective review.

METHODS

Patients from a tertiary-care laryngology practice over a 10-year period with autoimmune or idiopathic subglottic stenosis (SGS) were included. Patients with a history of prolonged intubation or other causes of iatrogenic stenosis were excluded. PGS was confirmed on videostrobolaryngoscopy recordings by a fellowship-trained laryngologist. PGS type (1-4) was also recorded. Demographic information was recorded, and if applicable, autoimmune disease type was specified. Time until PGS was recorded along with the number of interventions. Chi-squared analysis was used to compare PGS in autoimmune and idiopathic SGS.

RESULTS

A total of 77 patients were identified with autoimmune (32 patients) or idiopathic (45 patients) subglottic stenosis. Autoimmune pathologies included systemic lupus erythematosus, granulomatosis with polyangiitis (GPA), rheumatoid arthritis, relapsing polychondritis, and sarcoidosis, with GPA the most common (14/32). Patients with autoimmune SGS had a higher rate of PGS (10 of 32) compared to idiopathic subglottic stenosis (1 of 45) for an odds ratio of 20 (95% CI: 2.4-166.4, P = .006). Patients with idiopathic SGS were more likely to be female (all 45 compared to 29/32 autoimmune, P = .07) and older (mean 53 (range 29-75) compared to 46 (20-82), P = .02).

CONCLUSIONS

In this large patient cohort, autoimmune SGS patients were found to have a higher likelihood of developing PGS compared to their idiopathic counterparts, suggesting that counseling for this progression may be warranted.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:1816-1820, 2021.

Idiopathic Subglottic Stenosis during Pregnancy: A Support Group Survey

OBJECTIVES

(1) To determine how pregnancy affects idiopathic subglottic stenosis (iSGS) symptoms. (2) To determine treatments utilized (including operating room (OR) and in-office procedures) for iSGS before, during, and after pregnancy.

METHODS

A 24-question survey was distributed to an international iSGS support group to assess the patient experience among individuals who have been pregnant with diagnosis of iSGS. Descriptive statistics and chi² analyses were completed.

RESULTS

A total of 413 iSGS patients participated; 84.7% (n = 350) of patients were diagnosed prior to menopause. A total of 25.5% patients reported being pregnant when they had airway stenosis; 71.1% of those reported more severe airway symptoms during pregnancy. The proportion of patients that reported requiring ≥1 OR interventions (microlaryngoscopy and bronchoscopy, laser, balloon dilation, or steroid injection) before, during and after pregnancy was the following, respectively: 37.3%, 35.6%, 51.3%. Whereas the proportion of patients that reported requiring ≥1 in-office interventions (awake balloon dilation or steroid injection) before, during and after pregnancy was the following, respectively: 13.6%, 11.8%, 15.8%. Number of pregnancies and age of diagnosis was not related to severity of symptoms or requiring more airway interventions (P > .05).

CONCLUSIONS

This survey reveals worsening of symptoms during pregnancy, however, this did not lead to increase in operative or clinic interventions to improve airway symptoms during pregnancy. Future avenues for research include optimizing management of airway symptoms during pregnancy to limit OR-based interventions.

LEVEL OF EVIDENCE

Level IV.

Familial Aggregation in Idiopathic Subglottic Stenosis

OBJECTIVE

To evaluate inheritance patterns and define the familial clustering rate of idiopathic subglottic stenosis (iSGS).

STUDY DESIGN

Retrospective observational study.

SETTING

International multicenter collaborative of >30 tertiary care centers.

METHODS

Patients with a clinically confirmed iSGS diagnosis within the North American Airway Collaborative's iSGS¹⁰⁰⁰ cohort consented between 2014 and 2018 were eligible for enrollment. Patient demographics and disease severity were abstracted from the collaborative's iSGS longitudinal registry. Pedigrees of affected families were created.

RESULTS

A total of 810 patients with iSGS were identified. Positive family history for iSGS was reported in 44 patients in 20 families. The rate of familial clustering in iSGS is 2.5%. Mean age of disease onset is 42.6 years. Of the 44 patients with familial aggregation of iSGS, 42 were female and 2 were male; 13 were mother-daughter pairs and 2 were father-daughter pairs. There were 3 sister-sister pairs. There was 1 niece-aunt pair and 2 groups of 3 family members. One pedigree demonstrated 2 affected mother-daughter pairs, with the mothers being first-degree paternal cousins. Inheritance is non-Mendelian, and anticipation is present in 11 of 13 (84%) parent-offspring pairs. The mean age of onset between parents (48.4 years) and offspring (36.1 years) was significantly different (P = .016).

CONCLUSION

This study quantifies the rate of familial clustering of iSGS at 2.5%. Inheritance is non-Mendelian, and disease demonstrates anticipation. These data suggest that there may be a genetic contribution in iSGS.

Utility of Routine Spirometry Measures for Surveillance of Idiopathic Subglottic Stenosis

Importance

Because of the recurrent nature of idiopathic subglottic stenosis, routine follow-up is necessary for monitoring progression of stenosis. However, no easily accessible, standardized objective measure exists to monitor disease progression.

Objective

To determine whether peak expiratory flow (PEF) can be used as a reliable and easily accessible biometric indicator of disease progression relative to other validated spirometry measures in patients with idiopathic subglottic stenosis.

Design, Setting, and Participants

Prospectively collected data on PEF, expiratory disproportion index (EDI), and total peak flow (TPF) from 42 women with idiopathic subglottic stenosis without comorbid lower airway or parenchymal lung disease who were treated at a single tertiary referral center between 2014 and 2018 were analyzed. The mean follow-up period was 18.2 months (range, 2-40 months). Ten patients initially screened were not included in the analysis owing to comorbid glottic or supraglottic stenosis or nonidiopathic etiology.

Main Outcomes and Measures

Measurements of PEF, EDI, and TPF were taken at preoperative visits and at all other visits.

Results

Forty-two women (mean age, 51.5 years; 98% white [n = 41]) met the inclusion criteria. The area under the curve for PEF was 0.855 (95% CI, 0.784-0.926). The optimal cutoff value was 4.4 liters per second (264 L/min), with a sensitivity and specificity of 84.4% and 82.0%, respectively. The area under the curve for EDI was 0.853 (95% CI, 0.782-0.925). For TPF, this was 0.836 (95% CI, 0.757-0.916).

Conclusions and Relevance

This study provides evidence supporting the use of PEF as a simple, efficient, and accessible way of monitoring progression of idiopathic subglottic stenosis and predicting receipt of surgical intervention. Sensitivity and specificity of PEF were comparable to those of the more complex measures of TPF and EDI.

Serial In-Office Intralesional Steroid Injections in Airway Stenosis

Importance

Endoscopic dilation is the mainstay treatment strategy for subglottic and proximal tracheal stenosis (SGS/PTS). Its major limitation is restenosis requiring repeated surgery. Intralesional steroid injection (ISI) is a promising adjunctive treatment aimed at prolonging the effects of dilation.

Objective

To evaluate the association of serial in-office ISI after endoscopic dilation with surgery-free interval (SFI) in adults with SGS/PTS.

Design, Setting, and Participants

A retrospective study of adults with SGS/PTS who underwent at least 2 consecutive in-office ISI at the University of Southern California, Keck School of Medicine, over a 3-year period was conducted.

Exposure

Serial ISI with triamcinolone 40 mg/mL using topical anesthesia, spaced 3 to 6 weeks apart.

Main Outcomes and Measures

Surgery-free interval, number of dilations, need for open airway surgery, decannulation rate, and adverse events. Patients with previous dilations and sufficient follow-up time were included in a comparative analysis of SFI before and after ISI. The Mann-Whitney U test was applied for comparisons.

Results

Twenty-four patients met eligibility criteria. Mean (SD) age was 50.1 (15.1) years; 18 (75%) were female. Ten (42%) patients had idiopathic, 8 (33%) had traumatic, and 6 (25%) had rheumatologic-related SGS/PTS. Mean (SD) follow-up time was 32.3 (33.4) months. Patients underwent mean (SD) 4.08 (1.91) injections. Seventeen (71%) patients have not undergone further surgery after ISI. Mean (SD) SFI was 17.8 (12.8) months overall and was 15.7 (10.6) months for idiopathic, 13.8 (9.9) for traumatic, and 26.7 (16.9) for rheumatologic-related SGS/PTS. Twenty-one (88%) patients underwent dilation(s) prior to ISI. Among patients who fulfilled eligibility criteria for comparison of SFI before and after ISI, SFI improved from 10.1 months before, to 22.6 months after ISI (mean difference, 12.5 months; 95% CI, -2.1 to 27.2 months). Three of 6 patients (all with traumatic SGS/PTS) presenting with a tracheotomy were decannulated. No patients required open airway surgery after ISI. There were no adverse events associated with ISI.

Conclusions and Relevance

Serial in-office ISI are safe and well-tolerated in adults with SGS/PTS. This technique can reduce the surgical burden on these patients and may obviate the need for future airway intervention.

Predictors of recurrence after surgical treatment of idiopathic progressive subglottic stenosis

Idiopathic progressive subglottic stenosis is a rare cause of tracheal narrowing. Partial cricotracheal resection and anastomosis can cure idiopathic stenosis, even if some patients may require multiple interventions and experience voice and swallowing deterioration. We investigated risk factors for retreatment and assessed the impact of crico-tracheal resection on functional parameters. We conducted a retrospective multicentric study on 44 female patients (mean age 52.6 ± 13.1 years) affected by idiopathic stenosis and treated by crico-tracheal resection between 2002 and 2016. Functional outcomes after crico-tracheal resection were assessed by the airway-dyspnoea-voice-swallowing score (range 1-5, with “1” expressing normal and “5” completely altered function). Previous treatments, grade of stenosis, site, airway comorbidities, age and resection length were tested as predictors of postoperative complications and number of additional treatments, using bivariate and multivariate analysis. The overall decannulation rate was 97.3%. The dyspnoea score improved (mean variation 1.4 ± 1.0; p < 0.001), while voice and swallowing were negatively affected (mean variation 1.6 ± 0.9 and 0.5 ± 0.7, respectively; p < 0.001). Airway comorbidities were associated with a higher rate of complications (p < 0.05). Retreatments were more frequent in patients with postoperative complications (p < 0.05). The length of resection correlated with the number of subsequent treatments (R = 0.52; p < 0.01). At multivariate analysis, post-operative complications were predicted by comorbidities and disease stage (p < 0.05); number of retreatments was linked to the length of resection (p < 0.05) as well as with the application of mitomycin C (p < 0.001). Crico-tracheal resection for idiopathic progressive subglottic stenosis offers good functional results in terms of airway patency. These data suggest that a higher complication rate can be expected in patients affected by comorbidities. Moreover, more extensive surgical resection seems to be associated with the occurrence and number of subsequent retreatments. On the contrary, the local application of an anti-proliferative drug does not seem to be of use in preventing recurrences.

[Laryngo-Tracheal Resection as an Alternative to Permanent Tracheostomy]

INTRODUCTION

 Cervical stenosis of the trachea caused by tracheotomy, tumor or without defined reason (idiopathic) can be treated by resection and anastomosis with good early and long-term results. Involvement of the ring cartilage makes the procedure technically demanding and increases the risk of morbidity. We describe our technique of laryngotracheal resection and reconstruction and compare the perioperative results with standard tracheal resection.

PATIENTS AND METHODS

 Between January 2005 and December 2015, we performed about 800 procedures on the trachea including 76 standard cervical tracheal resections and 35 laryngotracheal resection. Resections were carried out with direct anastomosis without intraoperative tracheotomy or intralaryngeal stenting. Patient records were retrospectively analysed for perioperative data.

RESULTS

 The main cause of stenosis or defect of the trachea and operation was preceding tracheotomy. Idiopathic stenosis, tumors and subglottic stenosis in Wegener disease were less common. There were no disturbances of healing of the anastomosis in any patient. Tracheotomy in the course of treatment for intralaryngeal swelling or recurrent nerve palsy was necessary in 3 (standard) and 2 (laryngotracheal) patients. Postoperative tracheostomy was closed in all patients within 3 months. Pulmonary complications and recurrent nerve palsy occurred in 5/4 and 2/2 of the patients without significant differences between the 2 groups. One patient died in each group from pulmonary complications.

CONCLUSION

 The laryngotracheal resection is a relevant part of cervical tracheal surgery. It can be performed without significantly higher morbidity and can restore lung function and quality of voice.

Body Surface Area Is Not a Reliable Predictor of Tracheal Tube Size in Children

Objectives

The age-based Cole formula has been employed for the estimation of endotracheal tube (ETT) size due to its ease of use, but may not appropriately consider growth rates among children. Child growth is assessed by calculating the body surface area (BSA). The association between the outer diameter of an appropriate uncuffed-endotrachealtube (ETT-OD) and the BSA values of patients at 24–96 months of age was our primary outcome.

Methods

Cole formula, BSA, age, height, weight and ultrasound measurement of subglottic-transverse-diameter were evaluated for correlations with correct uncuffed ETT-OD. The Cole formula, BSA, and ultrasound measurements were analyzed for estimation rates in all patients and age subgroups. The maximum allowed error for the estimation of ETT-OD was ≤0.3 mm. Patients’ tracheas were intubated with tubes chosen by Cole formula and correct ETT-OD values were determined using leak test. ETT exchange rates were recorded.

Results

One-hundred twenty-seven patients were analyzed for the determination of estimation rates. Thirteen patients aged ≥72 months were intubated with cuffed ETT-OD of 8.4 mm and were accepted to need uncuffed ETT-OD >8.4 mm in order to be included in estimation rates, but excluded from correlations for size analysis. One-hundred fourteen patients were analyzed for correlations between correct ETT-OD (determined by the leak test) and outcome parameters. Cole formula, ultrasonography, and BSA had similar correct estimation rates. All three parameters had higher underestimation rates as age increased.

Conclusion.

The Cole formula, BSA, and ultrasonography had similar estimation rates in patients aged ≥24 to ≤96 months. BSA had a correct estimation rate of 40.2% and may not be reliable in clinical practice to predict uncuffedETT-size.

Patient Preferences in Subglottic Stenosis Treatment: A Discrete Choice Experiment

Objectives Subglottic stenosis can be addressed with several different surgical techniques, but patient preferences for these treatment modalities are poorly understood. Economic methods are increasingly being used to understand how patients make decisions. The objective of this pilot study was to assess preferences in subglottic stenosis treatment using patient-centric stated preference techniques. Study Design Discrete choice experiment (DCE). Setting Academic research facility. Subjects and Methods A computer-based DCE was administered in a monitored setting to volunteers from the general population. Signs and symptoms of subglottic stenosis were described, and participants were asked to imagine they had subglottic stenosis. Hypothetical treatments were offered, with 5 systematically varied attributes: need for external incision, length of hospital stay, postoperative voice quality, likelihood of repeat procedures, and risk of complication. A conditional logistic model was used to assess the relative attribute importance. Results In total, 162 participants were included. Attributes with the greatest impact on decision making included potential need for repeat procedures (importance 30.2%; P < .001), amount of operative risk (importance 28.1%; P < .001), and postoperative voice quality (importance 27.7%; P < .001), whereas presence of incision (importance 5.0%; P = .001) was less important, and hospital stay was not (importance 9.0%; P = .089). Based on aggregate responses for these attributes, the model demonstrated that most participants (80.4%) would prefer endoscopic surgery for subglottic stenosis as opposed to open tracheal resection (19.6%). Conclusion In this pilot population, most participants preferred voice-sparing, low-risk procedures as treatment for subglottic stenosis, consistent with an endoscopic approach, even if multiple procedures were required.

A retrograde y-stenting of the trachea for treatment of mediastinal fistula in an unusual situation

INTRODUCTION

Stents have been used for quite some time for the treatment of benign and malignant airway stenosis. Silicon stents are preferred for benign situations, whereas metallic self-expanding stents are preferred for malignant comorbidities.

PATIENT AND METHODS

In general, stents can be placed in different approach directions, although in pulmonary medicine it is logical to apply only antegrade techniques - until now. A 63-year-old patient, 168 cm height and 53 kg weight on referral, suffered chronical diseases. The patient was diagnosed with a papillary thyroid carcinoma in 1989, which was treated by resection and radiotherapy. In the following years, she developed a stenosis of the esophagus. The decision to try endobronchial stenting was made upon the plan to close that fistula with a pedicled omentum majus replacement through the diaphragmal opening of the esophagus. This surgical plastic needed an abutment and a secured continuous airway replacement above the tracheostoma level. A Freitag stent (FS), 11 cm in length (110-25-40) and an inner diameter of 13 mm, was placed successfully retrograde into the trachea and completely bridged the big fistula. Unfortunately the patient passed away due to pulmonary infections after several weeks.

DISCUSSION

In this case report, a successful but unusual case of retrograde stent placement of a modified FS is presented.

Evaluating the utility of serological testing in laryngotracheal stenosis

OBJECTIVES/HYPOTHESIS

Whereas mechanical (traumatic) causes of laryngotracheal stenosis (LTS) are identified based on history, autoimmune laryngotracheal stenosis (aLTS) and idiopathic laryngotracheal stenosis (iLTS) are often more difficult to differentiate. The objective of this study was to evaluate serologic testing in a large cohort of nonmechanical LTS patients to determine which tests, if any, lead clinicians to the etiology of the LTS.

STUDY DESIGN

Retrospective chart review.

METHODS

This study reviewed nonmechanical LTS patients seen at a tertiary medical center from 2007 to 2014. Data were obtained on patient demographics, associated preexisting autoimmune conditions, comorbidities, intubation history, and serologic testing.

RESULTS

Ninety-two records were reviewed. Twenty-three (25%) patients were found to have autoimmune disease; 69 (75%) met criteria for iLTS. A history of cigarette smoking was more significant in the aLTS group than the iLTS group (P < .001). Antineutrophil cytoplasmic antibody (ANCA) was positive only in patients with known granulomatosis with polyangiitis (GPA). All other serological testing was equivocal between the two cohorts.

CONCLUSIONS

Differentiating iLTS from aLTS has proven difficult. The lack of information about the two entities has resulted in variability in the diagnostic workup to distinguish them. This study's finding of a more significant smoking history in the aLTS group correlates with the literature, which suggests an inflammatory effect of smoking cigarettes and an association with autoimmune disease. The only significant cohort of patients in this study found to have positive serological testing correlated with a diagnosable condition responsible for LTS was GPA patients with positive ANCA.

LEVEL OF EVIDENCE

4. Laryngoscope, 127:1408-1412, 2017.