Acute Laryngeal Injury in Patients Undergoing Airway Screening at a Long-Term Acute Care Hospital.

BACKGROUND/OBJECTIVES: Acute laryngeal injury (ALgI) is an identified complication of prolonged intubation. Its evolution into mature stenosis and factors affecting decannulation are unclear. This retrospective review aims to characterize the incidence and characteristics of ALgI development and decannulation. METHODS: Retrospective study of post-intubated patients with a tracheostomy seen for screening evaluation at a single long-term acute care hospital (LTACH) from 2019 to 2022. RESULTS: Patients were followed for an average of 115 days after extubation. Forty-nine of 119 adult patients had ALgI. Those with ALgI were more likely female (61% vs. 35.7%, p = 0.006) with higher body mass index (BMI; 32.9 vs. 28.1, p = 0.03) and lower height (166 vs. 171.1 cm, p = 0.01). Decannulation rates in patients with ALgI were 69.4% compared to 84.3% in patients without ALgI (p = 0.053). Patients with ALgI were scoped more quickly post-extubation (28.8 vs. 36.6 days, p = 0.04), but time to decannulation did not differ (66.6 vs. 81.2 days, p = 0.74). Lower CCI (4.03 vs 6.93) and lack of tobacco use (41.2% vs 73.3%) were associated with successful decannulation (p = 0.038, p = 0.0008). Patients with ALgI treated conservatively (observation or medical management) were decannulated up to 71 days post-extubation. Further decannulations only occurred with surgical intervention. CONCLUSIONS: Female gender, higher BMI, and shorter height are associated with ALgI among patients undergoing a LTACH screening evaluation. CCI and tobacco have a negative association with decannulation success. Among the ALgI cohort, no patient treated conservatively was decannulated after 71 days. LEVEL OF EVIDENCE: 4 Laryngoscope, 2024.

The Effect of Laser-Resistant Endotracheal Tube Design on Airflow Dynamics: A Benchtop and Clinical Study.

OBJECTIVE: Compare ventilation pressures of 2 endotracheal tube designs used in laser airway surgery in clinical practice and with a benchtop model to elucidate differences and understand the design elements that impact airflow dynamics. METHODS: Ventilatory and aerodynamic characteristics of the laser resistant stainless-steel endotracheal tube (LRSS-ET) design and the laser resistant aluminum-wrapped silicone endotracheal tube (LRAS-ET) design were compared. Ventilatory parameters were collected for 32 patients undergoing laser-assisted airway surgery through retrospective chart review. An in vitro benchtop simulation measured average resistance and centerline turbulence intensity of both designs at various diameters and physiological frequencies. RESULTS: Baseline patient characteristics did not differ between the 2 groups. Clinically, the median LRAS-ET peak inspiratory pressure (PIP; 21.00 cm H2O) was significantly decreased compared to LRSS-ET PIP (34.67 cm H2O). In benchtop simulation, the average PIP of the LRAS-ET was significantly lower at all sizes and frequencies. The LRSS-ET consistently demonstrated an increased resistance, although no patterns were observed in turbulence intensity data between both designs. CONCLUSION: The benchtop model demonstrated increased resistance in the LRSS-ET compared to the LRAS-ET at all comparable sizes. This finding is supported by retrospective ventilatory pressures during laser airway surgery, which show significantly increased PIPs when comparing identically sized inner diameters. Given the equivocal turbulence intensity data, these differences in resistance and pressures are likely caused by wall roughness and intraluminal presence of tubing, not inlet or outlet geometries. The decreased PIPs of the LRAS-ET should assist in following lung protective ventilator management strategies and reduce risk of pulmonary injury and hemodynamic instability to the patient.

Comparative Treatment Outcomes for Idiopathic Subglottic Stenosis: 5-Year Update.

The North American Airway Collaborative (NoAAC) previously published a 3-year multi-institutional prospective cohort study showing variation in treatment effectiveness between 3 primary surgical techniques for idiopathic subglottic stenosis (iSGS). In this report, we update these findings to include 5 years of data evaluating treatment effectiveness. Patients in the NoAAC cohort were re-enrolled for 2 additional years and followed using the prespecified published protocol. Consistent with prior data, prospective observation of 487 iSGS patients for 5 years showed treatment effectiveness differed by modality. Cricotracheal resection maintained the lowest rate of recurrent operation (5%), followed by endoscopic resection with adjuvant medical therapy (30%) and endoscopic dilation (50%). These data support the initial observations and continue to provide value to providers and patients navigating longitudinal decision-making. Level of evidence: 2-prospective cohort study.

Clinical Characteristics of the Cervical Inlet Patch: A Case Series.

Objective: The goal of this study was to characterize the symptoms and outcomes of patients with a symptomatic cervical inlet patch (CIP). Study Design: Retrospective case series. Setting: Tertiary care laryngology clinic in Charlottesville, Virginia. Methods: A retrospective chart review of the patient's demographics, comorbidities, prior workup, interventions, and response to treatment was performed. All patients received flexible nasolaryngoscopy and barium swallow study. The analysis was descriptive. Results: Eight patients (6 female) were followed for the management of symptoms related to CIP. The mean age at presentation to our clinic was 64.9 (standard deviation = 15.7). Five out of 8 patients presented with a chief complaint of dysphagia, and the remaining 3 with chronic coughs. Five out of 8 patients demonstrated findings of laryngopharyngeal reflux (LPR) including vocal fold edema, mucosal erythema, or postcricoid edema. Swallow study demonstrated hiatal hernia in 3 of 8 patients, and cricopharyngeal (CP) dysfunction (CP hypertrophy, CP bar, and Zenker's diverticulum) in 3 of 8 patients. One patient presented with a history of Barrett's esophagus. Treatment included increased acid suppression therapy and management of coexisting esophageal pathologies. Ablative procedures were performed in 5 out of 8 cases, with 2 patients requiring repeat procedures. All patients experience subjective symptom improvement. Conclusion: CIP tends to present in complex patients with multifactorial dysphagia, with the most common symptoms being dysphagia and cough. Clinical features of CIP overlap with other more common pathologies encountered by otolaryngologists including LPR and CP dysfunction, and future prospective studies in larger populations should seek to clarify these associations.

A Simple and Reproducible In Vivo Rabbit Phonation Model for Glottic Insufficiency.

OBJECTIVE: The objective of this study is to describe an in vivo rabbit phonation model for glottic insufficiency that is simple and reproducible by means of unilateral transcricothyroid laryngeal muscle stimulation and high-speed video recordings of evoked phonation. STUDY DESIGN: Nonrandomized controlled animal trial. SETTING: Academic medical center. METHODS: A single operation including evoked phonation with bilateral and unilateral transcricothyroid laryngeal muscle stimulation conditions was modeled using 6 New Zealand white rabbits. The effect of stimulation method on glottic cycle, pitch, and loudness was compared. Endoscopic recordings using 5000 frames-per-second image capture technology and audiologic recordings were obtained for all phonation conditions. Primary outcome measures included means of maximum glottal area (MGA)/length pixel ratio, right and left amplitude/length pixel ratios, calculated cycle frequency, auditory recorded frequency, and maximum auditory intensity. Measurements were obtained via pixel counts using ImageJ. RESULTS: Mean MGA/length was significantly greater with unilateral, 20.30, vs bilateral, 9.62, stimulation (P = .043). Mean frequency of 479.92 Hz vs 683.46 Hz (P = .027) and mean maximum intensity of 76.3 dB vs 83.5 dB (P = .013) were significantly increased from unilateral to bilateral stimulation. There was no significant difference in mean right amplitude/length between unilateral and bilateral. CONCLUSION: The described model demonstrates a simple and reproducible means of producing glottic insufficiency due to unilateral vocal fold bowing and represents a pathway for better understanding the biomechanics and pathophysiology of glottic insufficiency due to superior laryngeal nerve injury and vocal fold immobility and offers the potential to compare treatment modalities through in vivo study.

Flexible Versus Rigid Laryngoscopy: A Prospective, Blinded Comparison of Image Quality.

OBJECTIVE: To compare flexible distal-chip laryngoscopy (FDL) and rigid telescopic laryngoscopy (RTL) in image quality and diagnostic ability. STUDY DESIGN: Prospective cohort study; blinded comparison. METHODS: Eighteen normal adult subjects were recruited to undergo both FDL and RTL and normalized videos were recorded. Three blinded laryngologists compared the videos for color fidelity, illumination, resolution, and vascularity, and indicated superiority with FDL, RTL, or no difference. Raters also reported if an abnormality was seen and in which video it was better visualized. Videos for two subjects were repeated to assess intra-rater reliability, making 20 video comparisons across 3 raters for a total of 60 ratings. Differences in responses were analyzed via Mann-Whitney U and Pearson Χ2. Inter-rater reliability was assessed via Fleiss' kappa, and intra-rater reliability was assessed via percent agreement. RESULTS: RTL was rated superior in all categories of image quality (47 vs 5 vs 8, P < 0.01; 47 vs 7 vs 6, P < 0.01; 51 vs 5 vs 4, P<0.01; 44 vs 9 vs 7, P < 0.01, respectively). An abnormality was seen 33 times with both modalities and 6 times with RTL only. When seen with both modalities, visualization was superior in RTL compared with FDL (29 vs 4, P <0.01). CONCLUSIONS: There was significant superiority of RTL in all categories of image quality, with slight inter-rater agreement for color fidelity, resolution, and vascularity. RTL was also significantly better for visualization of abnormalities. These findings suggest superior image quality in RTL compared with FDL, but further research is required to determine if this difference is clinically significant.

Practice Patterns and Barriers in Botulinum Toxin Injection for the Treatment of Voice Disorders.

Laryngeal botulinum toxin injection is an important treatment modality for spasmodic dysphonia and other laryngeal disorders. We sought to compare usage patterns of laryngeal botulinum toxin injections for voice disorders and to identify and quantify inefficiencies and barriers in providing this treatment. A 26 item survey was written and approved for distribution by the American Academy of Otolaryngology-Head and Neck Surgery and the National Spasmodic Dysphonia Association. It was distributed to Otolaryngologists who perform laryngeal botulinum toxin injections via the e-mail lists of the National Spasmodic Dysphonia Association provider database, American Academy of Otolaryngology-Head and Neck Surgery Voice Committee and the American Laryngological Association Neurolaryngology Study Group. There were 81 survey participants who collectively reported performing >1700 laryngeal botulinum toxin injections for voice disorders monthly (Mean = 21.5 pts/month). Regarding botulinum toxin A (BtxA) vial use, 54% of participants reported using multiple doses per vial for different patients during a single clinic day, while 14% reported using pharmacy predrawn single use aliquots. A combination of usage practices was reported by 7% of participants. Using an individual vial per patient and discarding the unused remainder was reported by 26% of participants with an associated annual cost in wasted BtxA of $84,300 per physician. There is wide variation in injection practices regarding management of BtxA vials and adherence to an individual vial per patient policy is associated with significant waste of health care resources. Alternative approaches to BtxA vial use could positively impact health care resource utilization.

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.

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.

Development of a microporous annealed particle hydrogel for long-term vocal fold augmentation.

OBJECTIVES/HYPOTHESIS: The purpose of this study was to develop and provide evidence of a novel permanent injectable biomaterial for vocal fold augmentation with the potential to treat glottic incompetence by evaluating its performance in two animal models. STUDY DESIGN: Animal model. METHODS: Microporous annealed particle (MAP) hydrogel was fabricated using a water-in-oil emulsion method and synthetically tuned to match the stiffness modulus of native vocalis muscle. Thirty-two New Zealand White rabbits were administered unilateral injections of MAP (n = 16), saline (n = 8), and the clinical standard hyaluronic acid (Restylane-L) (n = 8), and evaluated at day 0, and 6-week, 4-month, and 6-month endpoints. Induced vocal fold vibration was recorded with a high-speed camera prior to euthanization, with glottic closure and mucosal wave characteristics assessed both quantitatively and qualitatively by an experienced voice clinician. Histologic analysis was performed to assess scaffold permanence, immunogenicity, and vascularization within the scaffold. RESULTS: Histologic analysis confirmed the MAP gel treatment group maintained its volume without migration for 6 months postimplantation. Immune staining showed minimal to nonexistent immunogenicity over the course of the implant lifetime. Extensive tissue integration and vascularization was observed histologically within the MAP gel group by immunofluorescence staining. Mucosal wave was not impaired by any of the injected materials, including the MAP gel augmentation. CONCLUSIONS: MAP gel is a nonresorbable biostimulatory injectable implant that provides superior tissue integration, stiffness matching, and permanence compared to current injectable implants, with retained biomechanical function, suggesting its potential as a new therapeutic for glottic incompetence. LEVEL OF EVIDENCE: NA Laryngoscope, 130:2432-2441, 2020.

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.

Disease homogeneity and treatment heterogeneity in idiopathic subglottic stenosis.

OBJECTIVES/HYPOTHESIS: Idiopathic subglottic stenosis (iSGS) is a rare and potentially life-threatening disease marked by recurrent and progressive airway obstruction frequently requiring repeated surgery to stabilize the airway. Unknown etiology and low disease prevalence have limited the ability to characterize the natural history of iSGS and resulted in variability in surgical management. It is uncertain how this variation relates to clinical outcomes. STUDY DESIGN: Medical record abstraction. METHODS: Utilizing an international, multi-institutional collaborative, we collected retrospective data on patient characteristics, treatment, and clinical outcomes. We investigated variation between and within open and endoscopic treatment approaches and assessed therapeutic outcomes; specifically, disease recurrence and need for tracheostomy at last follow-up. RESULTS: Strikingly, 479 iSGS patients across 10 participating centers were nearly exclusively female (98%, 95% confidence interval [CI], 96.1-99.6), Caucasian (95%, 95% CI, 92.2-98.8), and otherwise healthy (mean age-adjusted Charlson Comorbidity Index 1.5; 95% CI, 1.44-1.69). The patients presented at a mean age of 50 years (95% CI, 48.8-51.1). A total of 80.2% were managed endoscopically, whereas 19.8% underwent open reconstruction. Endoscopic surgery had a significantly higher rate of disease recurrence than the open approach (chi(2) = 4.09, P = 0.043). Tracheostomy was avoided in 97% of patients irrespective of surgical approach (95% CI, 94.5-99.8). Interestingly, there were outliers in rates of disease recurrence between centers using similar treatment approaches. CONCLUSION: Idiopathic subglottic stenosis patients are surprisingly homogeneous. The heterogeneity of treatment approaches and the observed outliers in disease recurrence rates between centers raises the potential for improved clinical outcomes through a detailed understanding of the processes of care. LEVEL OF EVIDENCE: 4. Laryngoscope, 126:1390-1396, 2016.

Tubeless tracheotomy for survival airway surgery in the leporine model.

OBJECTIVES/HYPOTHESIS: The ideal animal experimental tracheostomy technique is one that is 1) safe and easy to perform, 2) requires no tracheostomy tube, and 3) requires minimal cleaning or suctioning to maintain patency. The leporine model for airway injury has been well established and offers an inexpensive and practical animal model for experimental evaluation. However, previous research has demonstrated a high mortality rate with survival airway surgery in rabbits. This study demonstrates the feasibility of airway management in the leporine model using a simple maturing suture tracheostomy that avoids a tracheostomy tube. STUDY DESIGN: Tracheostomy was performed in six New Zealand white rabbits in the setting of survival surgery over a 2-week study period. METHODS: A vertical tracheal incision was made from the second to the sixth tracheal ring. The anterior portion of the tracheal rings was removed and the skin surrounding the stoma was sutured down to the tracheal wall. The lateral tracheal wall was then suspended to the soft tissue in the lateral neck. RESULTS: All six rabbits survived the study period with minimal care and maintained stoma patency until sacrifice. Granulation tissue and edema were noted during the first week and largely resolved by the second week. An average of 5-mm-diameter stoma was measured 14 days after surgery without intraluminal stenosis or laryngeal edema. CONCLUSIONS: This method meets the defined criteria for the ideal experimental tracheostomy, demonstrating potential benefit in a laryngotracheal stenosis model and a rabbit model of evoked phonation.