Myer-Cotton Grade of Subglottic Stenosis Depends on Style of Endotracheal Tube Used.

OBJECTIVES: Determine percentage of subglottic stenosis using current endotracheal tube (ETT) cross-sectional areas as actual, compared with previously published ETT cross-sectional areas as expected, and determine if style of ETT could result in a change in percentage of stenosis or Myer-Cotton grade. STUDY TYPE: Cross-sectional study. DESIGN: Prospective analysis. METHODS: Eight styles of uncuffed pediatric ETT from four manufacturers ranging from 2.0 to 6.0 inner diameter (ID) were evaluated. ID and outer diameter (OD) measurements were obtained from each company's specification sheets. Cross-sectional area was calculated for each ETT using the formula (Area = πr2 ). The cross-sectional areas of each current ETT (actual) were compared with those of previously published ETTs (expected) based on age, and the degree of stenosis was calculated using the formula [1- (Area actual /Area expected )] × 100%. Ranges of percentage for each style of ETT were calculated. RESULTS: There was an increase in range of OD and area with increasing size of ETT ID, with the largest range in OD being 0.8 mm, and the largest range in area being 10.55 mm2 . The median interquartile range (IQR), range of percentage stenoses was 11 (5%), ranging from 0% to 21%. Seven of 28 (25%) ranges were found to span two Myer-Cotton grades. CONCLUSIONS: The Myer-Cotton grade of subglottic stenosis depends on the style of ETT used. Using updated values from currently available ETTs aims to keep this grading system valid with respect to surgical approach and outcomes following surgery. LEVEL OF EVIDENCE: NA Laryngoscope, 133:2808-2812, 2023.

Effect of a health system payment and quality improvement programme for tonsillectomy in Ontario, Canada: an interrupted time series analysis.

BACKGROUND: Tonsillectomy is among the most common and cumulatively expensive surgical procedures in children, with known variations in quality of care. However, evidence on health system interventions to improve quality of care is limited. The Quality-Based Procedures (QBP) programme in Ontario, Canada, introduced fixed episode hospital payment per tonsillectomy and disseminated a perioperative care pathway. We determined the association of this payment and quality improvement programme with tonsillectomy quality of care. METHODS: Interrupted time series analysis of children undergoing elective tonsillectomy at community and children's hospitals in Ontario in the QBP period (1 April 2014 to 31 December 2018) and the pre-QBP period (1 January 2009 to 31 January 2014) using health administrative data. We compared the age-standardised and sex-standardised rates for all-cause tonsillectomy-related revisits within 30 days, opioid prescription fills within 30 days and index tonsillectomy inpatient admission. RESULTS: 111 411 children underwent tonsillectomy: 51 967 in the QBP period and 59 444 in the pre-QBP period (annual median number of hospitals, 86 (range 77-93)). Following QBP programme implementation, revisit rates decreased for all-cause tonsillectomy-related revisits (0.48 to -0.18 revisits per 1000 tonsillectomies per month; difference -0.66 revisits per 1000 tonsillectomies per month (95% CI -0.97 to -0.34); p<0.0001). Codeine prescription fill rate continued to decrease but at a slower rate (-4.81 to -0.11 prescriptions per 1000 tonsillectomies per month; difference 4.69 (95% CI 3.60 to 5.79) prescriptions per 1000 tonsillectomies per month; p<0.0001). The index tonsillectomy inpatient admission rate decreased (1.12 to 0.23 admissions per 1000 tonsillectomies per month; difference -0.89 (95% CI -1.33 to -0.44) admissions per 1000 tonsillectomies per month; p<0.0001). CONCLUSIONS: The payment and quality improvement programme was associated with several improvements in quality of care. These findings may inform jurisdictions planning health system interventions to improve quality of care for tonsillectomy and other paediatric procedures.

Length of the Cricoid and Trachea in Children: Predicting Intubation Depth to Prevent Subglottic Stenosis.

OBJECTIVE: Define the length of the subglottis and trachea in children to predict a safe intubation depth. METHODS: Patients <18 years undergoing rigid bronchoscopy from 2013 to 2020 were included. The carina and inferior borders of the cricoid and true vocal folds were marked on a bronchoscope and distances were measured. Patient age, weight, height, and chest height were recorded. Four styles of cuffed pediatric endotracheal tubes (ETT) were measured and potential positions of each cuff and tip were calculated within each trachea using five depth of intubation scenarios. Multivariate linear regression was performed to identify predictors of subglottic and tracheal length. RESULTS: Measurements were obtained from 210 children (141 male, 69 female), mean (SD) age 3.21 (3.66) years. Patient height was the best predictor of subglottic length (R2 : 0.418): Lengthsg (mm) = 0.058 * height (cm) + 2.8, and tracheal length (R2 : 0.733): Lengtht (mm) = 0.485 * height (cm) + 21.3. None of the depth of intubation scenarios maintained a cuff-free subglottis for all ETT styles investigated. A formula for depth of intubation: Lengthdi (mm) = 0.06 * height (cm) + 8.8 found that no ETT cuffs would be in the subglottis and all tips would be above the carina. CONCLUSION: Current strategies for determining appropriate depth of intubation pose a high risk of subglottic ETT cuff placement. Placing the inferior border of the vocal cords 0.06 * height (cm) + 8.8 from the superior border of the inflated ETT cuff may prevent subglottic cuff placement and endobronchial intubation. LEVEL OF EVIDENCE: 4 Laryngoscope, 132:S1-S10, 2022.

A national study of choanal atresia in tertiary care centers in Canada - part II: clinical management.

BACKGROUND: To evaluate the clinical management of choanal atresia (CA) in tertiary centers across Canada. METHODS: Multi-centre case series involving six tertiary care pediatric hospitals across Canada. Retrospective chart review of patients born between 1980 and 2010 diagnosed with choanal atresia to a participating center. RESULTS: The health charts of 215 patients (59.6% female) with choanal atresia (CA) were reviewed. Mean age of initial surgical repair was 0.8 months for bilateral CA, and 48.6 months for unilateral CA. Approaches of surgical repair consisted of endoscopic transnasal (31.7%), non-endoscopic transnasal (42.6%), and transpalatal (25.2%). Stents were used on 70.7% of patients. Forty-nine percent of patients were brought back to the OR for a planned second look; stent removal being the most common reason (86.4%). Surgical success rate of initial surgeries was 54.1%. Surgical technique was not associated with rate of restenosis [χ2 (2) = 1.6, p = .46]. CONCLUSIONS: The present study is the first national multi-institutional study exploring the surgical outcomes of CA over a 30-year period. The surgical repair of CA presents a challenge to otolaryngologists, as the rate of surgical failure is high. The optimal surgical approach, age at surgical repair, use of stents, surgical adjuncts, and need for planned second look warrant further investigation.

A national study of choanal atresia in tertiary care centers in Canada - part I: clinical presentation.

BACKGROUND: To evaluate the clinical presentation of choanal atresia (CA) in tertiary centers across Canada. METHODS: Multi-centre case series involving six tertiary care pediatric hospitals across Canada. Retrospective chart review of patients born between 1980 and 2010 diagnosed with CA at a participating center. RESULTS: The health charts of 215 patients (59.6% female) with CA were reviewed and included in this study. The mean age of patients at time of CA presentation was 0.4 months (range 0.1 to 7.2 months) for bilateral CA and 37.8 months (range 0.1 to 164.1 months) for unilateral cases. The most common presenting symptoms for bilateral CA in decreasing order were respiratory distress (96.4%), feeding difficulties (68.2%), and rhinorrhea (65.5%), and for unilateral cases in decreasing order were rhinorrhea (92.0%), feeding difficulties (24.7%), and respiratory distress (18.0%). For the majority of patients (73.2%), the obstruction comprised mixed bony and membranous tissue, with only 10.5% presenting with a purely membranous obstruction. Familial history of CA was confirmed in only 3.3% of cases. One half of patients with CA presented with one or more associated anomalies and 30.6% had a syndrome. CONCLUSIONS: The present investigation is the first national multi-institutional study evaluating the clinical presentation of CA over three decades. The present cohort of CA patients presented with a breadth of co-morbidities with highly variable presentations, with bilateral cases being more severely affected than unilateral cases. Further investigation into hereditary linkages to CA development is warranted.

Patterns and Predictors of Metastatic Spread to the Neck in Pediatric Thyroid Carcinoma.

OBJECTIVE: Evaluate patterns and predictors of spread to the neck in pediatric metastatic differentiated thyroid carcinoma (DTC). METHODS: Patients <18 years old undergoing thyroidectomy by a single surgeon from January 2015 to December 2019 were included. Neck sublevels were removed separately according to AJCC boundaries. Clinical outcomes included nerve injury, hypocalcemia, hematoma, and residual tumor. RESULTS: Forty-eight children underwent thyroid surgery. Thirty (63%) were for malignancy, 27 (90%) of which were DTC. Nineteen (70%) patients with DTC underwent 24 neck dissections; 19 central plus lateral and 5 central alone. The female to male ratio increased from 1:1 to 3:1 with age. Two children with lateral neck involvement had sub-centimeter primaries. Patients requiring neck dissection were more likely to have 1) diffuse sclerosing or tall cell variant, 2) T3 or T4 disease, 3) genetic mutation, 4) lymphatic invasion, 5) extracapsular extension, 6) positive resection margin. Levels IIA (79%), III (89%), IV (84%), VI (100%) were most commonly involved. Levels IB (16%), IIB (16%), VB (16%) were also involved, often without involvement of adjacent levels. Permanent injuries included one unilateral recurrent laryngeal nerve, one mild marginal mandibular nerve and one mild accessory nerve. Hypocalcemia was highest following neck dissection for malignant disease. One patient was re-operated for a mediastinal node. Most patients with N1 disease received radioactive iodine. Most patients have no evidence or indeterminate disease on long-term follow-up. CONCLUSION: Children with lateral nodal spread from DTC should be considered for neck dissection including Levels IB, IIA, IIB, III, IV, VB, bilateral VI. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:E1002-E1009, 2021.

Recurrent laryngeal nerve monitoring with surface electrodes in pediatric thyroid surgery.

OBJECTIVE: To prospectively evaluate 1) use of endotracheal tube (ETT) surface electrodes for recurrent laryngeal nerve (RLN) monitoring in thyroid surgery in children, and 2) effects of thyroid surgery on the RLN in children. METHODS: Patients <18 years old undergoing thyroidectomy were included. Vocal cord mobility was assessed pre- and postoperatively. RLNs were monitored using adhesive or integrated electrodes. Recordings were made before and after dissection, and area under the curve and latency were compared using mixed models. RESULTS: Twenty-five children (44 nerves at risk), mean (standard deviation) age 13.1 (3.4) years (range 4.5-17.4 years), underwent thyroidectomy. Twelve (46%) monitors were adhesive. One nerve had unobtainable responses. Nerveäna Power Index (NPI) (Neurovision Medical Products, Ventura, CA) decreased, and latency increased pre- versus postdissection at all amplitudes (P < 0.0001), with change in slope of NPI affected by tumor size (P < 0.05). Postdissection, the NPI was lower, and the latency was longer when stimulating low in the neck versus near the cricothyroid joint at all stimulating amplitudes (P < 0.0001), with change in NPI related to tumor size (P < 0.0001). Changes were not associated with decreased vocal cord mobility, aspiration, or voice change. One patient had a temporary unilateral paresis that resolved by 7 weeks, and another had normal movement 3 weeks postoperatively and developed a paresis 2 months postoperatively. CONCLUSION: ETT surface electrodes are reliable for RLN monitoring in thyroid surgery in children. Thyroid surgery is associated with a decrease in RLN stimulability that is related to tumor size. The site of RLN stimulation matters when evaluating the nerve. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:1583-1589, 2020.

Lateral graft type 1 tympanoplasty using AlloDerm for tympanic membrane reconstruction in children.

OBJECTIVES: To describe the lateral graft type 1 tympanoplasty technique using AlloDerm for tympanic membrane reconstruction in children and to compare its surgical and audiometric outcomes with the traditional underlay type 1 tympanoplasty. METHODS: The records of 34 consecutive children undergoing type 1 tympanoplasty between 2004 and 2005 were reviewed; 18 received lateral graft tympanoplasty with AlloDerm and 16 received underlay tympanoplasty (8 AlloDerm and 8 temporalis fascia). Pre- and post-surgical audiograms, speech reception threshold, closure rate and complication rate were evaluated using one-way and repeated measures ANOVAs. RESULTS: Children who underwent lateral graft type 1 tympanoplasty pre-operatively had larger tympanic membrane perforations, worse pure tone averages, air bone gaps and speech reception thresholds as compared with children undergoing underlay type 1 tympanoplasty (P<0.001). Pure tone averages and air bone gaps improved significantly with surgery in both lateral and underlay type 1 tympanoplasty groups (P<0.05), with both groups achieving comparable postoperative audiometric outcomes (P>0.01). The lateral graft group demonstrated a higher perforation closure rate (94%) as compared with both underlay groups (88%). Complication rates were virtually non-existent. CONCLUSIONS: Despite larger perforations and worse pre-operative audiometric scores, children who underwent lateral graft type 1 tympanoplasty achieved comparable postoperative audiometric results and perforation closure rates as compared with children who underwent underlay type 1 tympanoplasty. Results suggest that lateral graft type 1 tympanoplasty using AlloDerm is effective for tympanic membrane reconstruction in children and should be used when temporalis fascia is not available or the extent of the perforation limits its use.

Auditory responses in cochlear implant users with and without GJB2 deafness.

OBJECTIVE/HYPOTHESIS: It is reasonable to suppose that the pattern of sensorineural damage along the length of the cochlea depends on the etiology of a hearing loss (HL). In GJB2-related deafness, we hypothesize that gap junction deficits are uniformly distributed and will result in similar damage along the length of the cochlea as compared with non-GJB2 subjects. We assessed this by measuring patterns of neural activity and hearing from apical versus basal cochlear implant electrode regions. STUDY DESIGN: This was a prospective, blind, controlled study. METHODS: Blood from 301 pediatric cochlear implant users was analyzed for mutations in GJB2 by direct sequencing. After exclusion of patients with monoallelic GJB2 mutations, associated syndromes, or risk factors for HL that were not congenital, 39 children with biallelic GJB2 mutations and 58 without GJB2 mutations were evaluated. Hearing was measured before implantation at frequencies ranging from 250 Hz to 8 kHz. After implantation, neural activity at the apical and basal ends of the implanted array was measured using electrically evoked compound action potentials of the auditory nerve (ECAPs) and evoked stapedius reflexes (ESRs). RESULTS: GJB2 and non-GJB2 groups were not significantly different with respect to sex, age at implantation, duration of auditory deprivation, hearing aid use, duration of aided hearing, ear implanted, implant model, or depth of insertion (P>.05). Children with GJB2-related HL had greater similarities between low- and high-frequency residual hearing and between neural activity electrically evoked at apical and basal regions of the cochlea as compared with children with non-GJB2-related HL who demonstrated larger deficits in basal regions. CONCLUSION: Results suggest more consistent spiral ganglion survival along the length of the cochlea in GJB2-related HL as compared with non-GJB2-related HL, which appears to involve a decreasing gradient of spiral ganglion survival from the apex to the base of the cochlea. Our findings support our premise that in GJB2-related HL, dysfunction of gap junctions likely occurs to a similar degree in the apical and basal regions of the cochlea. This knowledge might be used to customize implantable devices for patients with HL in the future.

Ethnicity and mutations in GJB2 (connexin 26) and GJB6 (connexin 30) in a multi-cultural Canadian paediatric Cochlear Implant Program.

OBJECTIVE: To determine the relationship between ethnicity and mutations in the GJB2 and GJB6 genes in multi-cultural patients enrolled in a Canadian paediatric Cochlear Implant Program. METHODS: Blood was analyzed from 65 paediatric cochlear implant users by direct sequencing of the coding region and intron/exon boundaries of the GBJ2 gene. Individuals heterozygous for one mutation in GJB2 or in whom mutations in GJB2 were not detected were analyzed for the common 342 kb deletion mutation D13S1830 in the GJB6 gene. Information regarding ethnicity of patients' families was obtained from patient records and/or interview. RESULTS: GJB2 mutations were found in 36.9% of paediatric cochlear implant users tested. Nine different GJB2 mutations were identified among individuals from 14 different countries of origin. Seventy-eight percent of all identified pathogenic GJB2 mutations were 35delG. Biallelic GJB2 mutations were found in 16 cochlear implant users (66.7% of GJB2 mutations). Three novel GJB2 sequence changes were identified: (1) a missense mutation T107C (L36P) in an individual of African decent; (2) a missense mutation G475T (D159Y) in an individual of Caribbean decent; (3) a regulatory region change 1-34C to T in an individual of African decent. GJB6-D13S1830 mutations were not found in any of the patients tested. Individuals of African, Caribbean and East Indian decent had different GJB2 mutations than the remainder of individuals tested. Patients of Asian, Italian, Spanish, Polish and Armenian decent were not found to carry mutations in GJB2 or the common GJB6-D13S1830 mutation. CONCLUSIONS: This study represents the largest number of biallelic GJB2 mutations isolated in a group of paediatric cochlear implant users to date. Numerous and diverse GJB2 mutations were found in this multi-cultural group of children. Even though GJB2 mutations have been widely reported in the literature, this discussion represents the first report of GJB2 mutations in a multi-ethnic population (Canadian), as compared with previous studies that investigated fairly homogeneous populations. The diversity of GJB2 mutations identified reinforces the importance of testing for changes in GJB2 by direct sequencing of the entire coding region rather than testing only for common mutations.