The nasal basal cell population shifts toward a diseased phenotype with impaired barrier formation capacity in allergic rhinitis.

BACKGROUND: The integrity of the airway epithelium is guarded by the airway basal cells that serve as progenitor cells and restore wounds in case of injury. Basal cells are a heterogenous population, and specific changes in their behavior are associated with chronic barrier disruption-mechanisms that have not been studied in detail in allergic rhinitis (AR). OBJECTIVE: We aimed to study basal cell subtypes in AR and healthy controls. METHODS: Single-cell RNA sequencing (scRNA-Seq) of the nasal epithelium was performed on nonallergic and house dust mite-allergic AR patients to reveal basal cell diversity and to identify allergy-related alterations. Flow cytometry, immunofluorescence staining, and in vitro experiments using primary basal cells were performed to confirm phenotypic findings at the protein level and functionally. RESULTS: The scRNA-Seq, flow cytometry, and immunofluorescence staining revealed that basal cells are abundantly and heterogeneously present in the nasal epithelium, suggesting specialized subtypes. The total basal cell fraction within the epithelium in AR is increased compared to controls. scRNA-Seq demonstrated that potentially beneficial basal cells are missing in AR epithelium, while an activated population of allergy-associated basal cells is more dominantly present. Furthermore, our in vitro proliferation, wound healing assay and air-liquid interface cultures show that AR-associated basal cells have altered progenitor capacity compared to nonallergic basal cells. CONCLUSIONS: The nasal basal cell population is abundant and diverse, and it shifts toward a diseased state in AR. The absence of potentially protective subtypes and the rise of a proinflammatory population suggest that basal cells are important players in maintaining epithelial barrier defects in AR.

A novel TASK channel antagonist nasal spray reduces sleep apnea severity in physiological responders: a randomized, blinded, trial.

Preclinical and human physiological studies indicate that topical, selective TASK 1/3 K+ channel antagonism increases upper airway dilator muscle activity and reduces pharyngeal collapsibility during anesthesia and nasal breathing during sleep. The primary aim of this study was to determine the effects of BAY2586116 nasal spray on obstructive sleep apnea (OSA) severity and whether individual responses vary according to differences in physiological responses and route of breathing. Ten people (5 females) with OSA [apnea-hypopnea index (AHI) = 47 ± 26 events/h (means ± SD)] who completed previous sleep physiology studies with BAY2586116 were invited to return for three polysomnography studies to quantify OSA severity. In random order, participants received either placebo nasal spray (saline), BAY2586116 nasal spray (160 µg), or BAY2586116 nasal spray (160 µg) restricted to nasal breathing (chinstrap or mouth tape). Physiological responders were defined a priori as those who had improved upper airway collapsibility (critical closing pressure ≥2 cmH2O) with BAY2586116 nasal spray (NCT04236440). There was no systematic change in apnea-hypopnea index (AHI3) from placebo versus BAY2586116 with either unrestricted or nasal-only breathing versus placebo (47 ± 26 vs. 43 ± 27 vs. 53 ± 33 events/h, P = 0.15). However, BAY2586116 (unrestricted breathing) reduced OSA severity in physiological responders compared with placebo (e.g., AHI3 = 28 ± 11 vs. 36 ± 12 events/h, P = 0.03 and ODI3 = 18 ± 10 vs. 28 ± 12 events/h, P = 0.02). Morning blood pressure was also lower in physiological responders after BAY2586116 versus placebo (e.g., systolic blood pressure = 137 ± 24 vs. 147 ± 21 mmHg, P < 0.01). In conclusion, BAY2586116 reduces OSA severity during sleep in people who demonstrate physiological improvement in upper airway collapsibility. These findings highlight the therapeutic potential of this novel pharmacotherapy target in selected individuals.NEW & NOTEWORTHY Preclinical findings in pigs and humans indicate that blocking potassium channels in the upper airway with topical nasal application increases pharyngeal dilator muscle activity and reduces upper airway collapsibility. In this study, BAY2586116 nasal spray (potassium channel blocker) reduced sleep apnea severity in those who had physiological improvement in upper airway collapsibility. BAY2586116 lowered the next morning's blood pressure. These findings highlight the potential for this novel therapeutic approach to improve sleep apnea in certain people.

Changes in the nasopharyngeal and oropharyngeal microbiota in pediatric obstructive sleep apnea before and after surgery: a prospective study.

OBJECTIVE: To explore the changes and potential mechanisms of microbiome in different parts of the upper airway in the development of pediatric OSA and observe the impact of surgical intervention on oral microbiome for pediatric OSA. METHODS: Before adeno-tonsillectomy, we collected throat swab samples from different parts of the oropharynx and nasopharynx of 30 OSA patients and 10 non-OSA patients and collected throat swab samples from the oropharynx of the above patients one month after the adeno-tonsillectomy. The 16 S rRNA V3-V4 region was sequenced to identify the microbial communities. The correlation analysis was conducted based on clinical characteristics. RESULTS: There was a significant difference of alpha diversity in different parts of the upper airway of pediatric OSA, but this difference was not found in children with non-OSA. Beta diversity was significantly different between non-OSA and pediatric OSA. At the genus level, the composition of flora in different parts is different between non-OSA and pediatric OSA. The correlation analysis revealed that the relative abundance of Neisseria was significantly correlated with obstructive apnea hypopnea index. Furthermore, the functional prediction revealed that pathways related to cell proliferation and material metabolism were significantly different between non-OSA and pediatric OSA. Besides, the adeno-tonsillectomy has minimal impact on oral microbiota composition in short term. CONCLUSION: The changes in upper airway microbiome are highly associated with pediatric OSA. The relative abundance of some bacteria was significantly different between OSA and non-OSA. These bacteria have the potential to become new diagnostic and early warning biomarkers.

NRP1 antagonism as a novel therapeutic target in nasal polyps of patients with chronic rhinosinusitis.

BACKGROUND: Neuropilin-1 (NRP1) is expressed on the surface epithelium of respiratory tract and immune cells, demonstrating its possible function in regulating the immune response in airway disease. However, its role in patient with chronic rhinosinusitis (CRS) remains unknown. This study aimed to elucidate the role of NRP1 in CRS with nasal polyps (CRSwNP). METHODS: Sinonasal biopsy specimens were immunohistochemically stained to investigate NRP1 expression. Double immunofluorescence, immunoblotting, and real-time polymerase chain reaction were performed to evaluate NRP1 in primary human nasal epithelial cells (hNECs). An NRP1 inhibitor was administered to a murine nasal polyp (NP) model. RESULTS: NRP1 was highly expressed in the epithelium in patients with CRSwNP compared to nasal tissue from controls and CRS without NP patients. NRP1 and vascular endothelial growth factor were upregulated in hNECs under hypoxia. Treatment with NRP1 inhibitor (EG00229) reduced the secretion of interleukin (IL)-1ß, IL-6, IL-8, and IL-33 cytokines, as well as inducible nitric oxide synthase, cyclooxygenase-2, and prostaglandin E2 in hNECs. We found that NRP1 was highly expressed in the airway epithelium in the murine NP model. The group treated with the NRP1 inhibitor had significantly fewer nasal polypoid lesions and reduced accumulations of immune cells. CONCLUSIONS: These findings reveal that NRP1 is upregulated in CRS and NP epithelium, and the inhibition of NRP1 may lead to a reduction in NP growth and immune cell infiltration. Our results suggest that NRP1 inhibition could be a novel possibility for treating nasal polyposis.

Causal Effects of Asthma on Upper Airway Diseases and Allergic Diseases: A Two-Sample Mendelian Randomization.

INTRODUCTION: Asthma is associated with upper airway diseases and allergic diseases; however, the causal effects need to be investigated further. Thus, we performed this two-sample Mendelian randomization (MR) analysis to explore and measure the causal effects of asthma on allergic rhinitis (AR), vasomotor rhinitis (VMR), allergic conjunctivitis (AC), atopic dermatitis (AD), and allergic urticaria (AU). METHODS: The data for asthma, AR, VMR, AC, AD, and AU were obtained from large-scale genome-wide association studies summarized recently. We defined single-nucleotide polymorphisms satisfying the MR assumptions as instrumental variables. Inverse-variance weighted (IVW) approach under random-effects was applied as the dominant method for causal estimation. The weighted median approach, MR-Egger regression analysis, MR pleiotropy residual sum and outlier test, and leave-one-out sensitivity analysis were performed as sensitivity analysis. Horizontal pleiotropy was measured using MR-Egger regression analysis. Significant causal effects were attempted for replication and meta-analysis. RESULTS: We revealed that asthma had causal effects on AR (IVW, odds ratio [OR] = 1.93; 95% confidence interval [CI], 1.74-2.14; p < 0.001), VMR (IVW, OR = 1.40; 95% CI, 1.15-1.71; p < 0.001), AC (IVW, OR = 1.65; 95% CI, 1.49-1.82; p < 0.001), and AD (IVW, OR = 2.13; 95% CI, 1.82-2.49; p < 0.001). No causal effect of asthma on AU was observed. Sensitivity analysis further assured the robustness of these results. The evaluation of the replication stage and meta-analysis further confirmed the causal effect of asthma on AR (IVW OR = 1.81, 95% CI 1.62-2.02, p < 0.001), AC (IVW OR = 1.44, 95% CI 1.11-1.87, p < 0.001), and AD (IVW OR = 1.85, 95% CI 1.42-2.41, p < 0.001). CONCLUSIONS: We revealed and quantified the causal effects of asthma on AR, VMR, AC, and AD. These findings can provide powerful causal evidence of asthma on upper airway diseases and allergic diseases, suggesting that the treatment of asthma should be a preventive and therapeutic strategy for AR, VMR, AC, and AD.

Continuous positive airway pressure and adherence in patients with different endotypes of obstructive sleep apnea.

Determining the endotypes of obstructive sleep apnea (OSA) has potential implications for precision interventions. Here we assessed whether continuous positive airway pressure (CPAP) treatment outcomes differ across endotypic subgroups. We conducted a retrospective analysis of data obtained from 225 patients with moderate-to-severe OSA from a single sleep centre. Polysomnographic and CPAP titration study data were collected between May 2020 and January 2022. One-month CPAP treatment adherence was followed. Obstructive sleep apnea endotypes, namely arousal threshold, collapsibility, loop gain, and upper airway gain were estimated from polysomnography and dichotomised as high versus low. We examined associations between endotypic subgroups and (1) optimal CPAP titration pressure, (2) CPAP-related improvements in sleep architecture (proportions of slow-wave and rapid eye movement (REM) sleep), and (3) CPAP adherence. We observed that patients with high collapsibility required a higher CPAP pressure than those with low collapsibility (∆ = 0.4 cmH2 O, 95% confidence interval [CI] = 0.3-1.7). A larger increase in slow-wave sleep and in REM sleep proportions after CPAP treatment were observed in patients with a high arousal threshold, high collapsibility, high loop gain, or high upper airway gain than in those with low levels of endotypes. High loop gain and high collapsibility were independently associated with longer CPAP use hours per night (∆ = 0.6 h, 95% CI = 0.2-1.5 and ∆ = 0.3 h, 95% CI = 0.03-1.5, respectively). In conclusion, different endotypic subgroups of OSA exhibit a difference in outcomes of CPAP treatment. Knowledge of endotypes may help clinicians to understand which patients are expected to benefit most from CPAP therapy prior to its administration.

OSA type-III and neurocognitive function.

Obstructive sleep apnea (OSA) due to a hypertrophy of the adenoids and/or the tonsils in otherwise healthy children is associated with neurocognitive dysfunction and behavioural disorders with various degrees of hyperactivity, aggressiveness, sometimes evolving to a label of attention-deficit hyperactivity disorder. Children with anatomical and/or functional abnormalities of the upper airways represent a very specific population which is at high risk of OSA (also called complex OSA or OSA type III). Surprisingly, the neurocognitive consequences of OSA have been poorly studied in these children, despite the fact that OSA is more common and more severe than in their healthy counterparts. This may be explained by that fact that screening for OSA and sleep-disordered breathing is not systematically performed, the performance of sleep studies and neurocognitive tests may be challenging, and the respective role of the underlining disease, OSA, but also poor sleep quality, is complex. However, the few studies that have been performed in these children, and mainly children with Down syndrome, tend to show that OSA, but even more disruption of sleep architecture and poor sleep quality, aggravate the neurocognitive impairment and abnormal behaviour in these patients, underlining the need for a systematic and early in life assessment of sleep and neurocognitive function and behaviour in children with OSA type III.

Effect of left paratracheal pressure on left carotid blood flow.

INTRODUCTION: Gautier et al. demonstrated that a compression in the left paratracheal region (left paratracheal pressure, LPP) can be used to seal the oesophagus. However, at this level, the left common carotid artery is very close to the carotid that could be affected during the manipulation. This study aimed to assess the hemodynamic effects of LPP on the carotid blood flow. METHODS: We prospectively included 47 healthy adult volunteers. We excluded pregnant women and people with anomalies of the carotid arteries. The common and internal carotid arteries were preliminarily studied with ultrasounds to exclude atheromatous plaques or vascular malformation. A planimetry of the common and internal carotid arteries was performed. Doppler echography served to measure the peak systolic (PSV) and end-diastolic velocities (EDV) in the common and internal carotid arteries. All measurements were repeated while applying LPP. RESULTS: Forty-seven participants were enrolled (32 women; mean [SD] age: 42 [13] years). The mean PSV difference [95% CI] in the left common carotid artery before and after LPP at the group level was -15.30 [-31.09 to 0.48] cm s-1 (p = .14). The mean surface difference [95% CI] in the left common carotid artery before and after LPP was 24.52 [6.11-42.92] mm2 (p = .11). Similarly, the same surface at the level of the left internal carotid artery changed by -18.89 [-51.59 to 13.80] mm2 after LPP (p = .58). CONCLUSIONS: Our results suggest that LPP does not have a significant effect on carotid blood flow in individuals without a carotid pathology. However, the safety of the manoeuvre should be evaluated in patients at risk of carotid anomalies.

Effects of avoidance versus use of neuromuscular blocking agents for facilitation of tracheal intubation in children and infants: a protocol for a systematic review, meta-analysis and trial sequential analysis.

BACKGROUND: The European Society of Anesthesiology and Intensive Care recommends the use of neuromuscular blocking agents (NMBA) in adults, to facilitate tracheal intubation and reduce its associated complications. Children who undergo tracheal intubation may suffer some of the same complications, however, no consensus exists regarding the use of NMBA for tracheal intubation in the pediatric population. We will explore the existing evidence assessing the effects of avoidance versus the use of NMBA for the facilitation of tracheal intubation in children and infants. METHODS: This protocol follows the preferred reporting items for systematic reviews and meta-analyses protocols recommendations. We will include all randomized controlled clinical trials assessing the effects of avoidance versus the use of NMBA for facilitation of tracheal intubation (oral or nasal) using direct laryngoscopy or video laryngoscopy in pediatric participants (<18 years). Our primary outcome is incidence of difficult tracheal intubation. Secondary outcomes include incidence of serious adverse events, failed intubation, events of upper airway discomfort or injury, and difficult laryngoscopy. We will conduct a thorough database search to identify relevant trials, including CENTRAL, MEDLINE, EMBASE, BIOSIS, Web of Science, CINAHL, and trial registries. Two review authors will independently handle the screening of literature and data extraction. Each trial will be evaluated for major sources of bias with the "classic risk of bias tool" used in the Cochrane Collaboration tool from 2011. We will use Review manager (RevMan) or R with the meta package to perform the meta-analysis. We will perform a trial sequential analysis on the meta-analysis of our primary outcome, providing an estimate of statistical reliability. Two review authors will independently assess the quality of the body of evidence using the grading of recommendations assessment, development, and evaluation (GRADE) approach. We will use GRADEpro software to conduct the GRADE assessments and to create "Summary of the findings" tables.

Relationship between airflow limitation in response to upper airway negative pressure during wakefulness and obstructive sleep apnea severity.

PURPOSE: The objective was to determine if alteration in airflow induced by negative pressure (NP) applied to participants' upper airways during wakefulness, is related to obstructive sleep apnea (OSA) severity as determined by the apnea-hypopnea index (AHI). METHODS: Adults 18 years of age or greater were recruited. All participants underwent overnight polysomnography to assess their apnea-hypopnea index (AHI). While awake, participants were twice exposed, orally, to -3 cm H2O of NP for five full breaths. The ratio of the breathing volumes of the last two breaths during NP exposure to the last two breaths prior to NP exposure was deemed the NP ratio (NPR). RESULTS: Eighteen participants were enrolled. A strong relationship between the AHI and the exponentially transformed NPR (ExpNPR) for all participants was observed (R2 = 0.55, p < 0.001). A multivariable model using the independent variable ExpNPR, age, body mass index and sex accounted for 81% of variability in AHI (p = 0.0006). A leave-one-subject-out cross-validation analysis revealed that predicted AHI using the multivariable model, and actual AHI from participants' polysomnograms, were strongly related (R2 = 0.72, p < 0.001). CONCLUSION: We conclude that ExpNPR, was strongly related to the AHI, independently of demographic factors known to be related to the AHI.

Upper airway morphology in adults with positional obstructive sleep apnea.

PURPOSE: To compare the anatomical balance and shape of the upper airway in the supine position between adults with positional obstructive sleep apnea (POSA) and adults with non-positional OSA (NPOSA). METHODS: Adults diagnosed with OSA (apnea-hypopnea index (AHI) > 10 events/h) were assessed for eligibility. POSA was defined as the supine AHI more than twice the AHI in non-supine positions; otherwise, patients were classified as NPOSA. Cone beam computed tomography (CBCT) imaging was performed for every participant while awake in the supine position. The anatomical balance was calculated as the ratio of the tongue size to the maxillomandibular enclosure size. The upper airway shape was calculated as the ratio of the anteroposterior dimension to the lateral dimension at the location of the minimal cross-sectional area of the upper airway (CSAmin-shape). RESULTS: Of 47 participants (28 males, median age [interquartile range] 56 [46 to 63] years, median AHI 27.8 [15.0 to 33.8]), 34 participants were classified as having POSA (72%). The POSA group tended to have a higher proportion of males and a lower AHI than the NPOSA group (P = 0.07 and 0.07, respectively). After controlling for both sex and AHI, the anatomical balance and CSAmin-shape were not significantly different between both groups (P = 0.18 and 0.73, respectively). CONCLUSION: Adults with POSA and adults with NPOSA have similar anatomical balance and shape of their upper airway in the supine position. TRIAL REGISTRATION: This study was registered with the Australian New Zealand Clinical Trials Registry (ANZCTR Trial ACTRN12611000409976).

Patient-reported experience with hypoglossal nerve stimulation in the treatment of obstructive sleep apnea.

BACKGROUND: Breathing-synchronized hypoglossal nerve stimulation (HNS) is routinely used as an alternative treatment for patients with obstructive sleep apnea (OSA). Significant and clinically relevant improvements in disease severity and OSA symptoms such as daytime sleepiness as well as overall quality of life have been reported in randomized-controlled trials and large real-world cohort studies. However, so far, few data exist on patient-reported experience with the treatment. METHODS: A structured survey with 22 questions was constructed using five-level Likert scales (1 = no agreement, 5 = complete agreement) to evaluate patient experience with HNS and perception of the treatment in the domains "Overall experience with therapy," "Experience with treatment process," and "Side-effects from treatment." Additional data were collected on current symptom status, measured with Epworth sleepiness scale (ESS) questionnaire, and OSA disease history. Multiple linear regression analysis was conducted to test associations of medical variables and response behavior. Correlations between variables and domains, as well as individual items, were assessed using Spearman rank test. RESULTS: A total of 75 patients from Germany who were treated with breathing-synchronized HNS were enrolled (mean age 57.3 years, 78% male), and 71 questionnaires with complete data were included for analysis. Two-thirds of participants (67%) had a history of OSA history for 5 years or longer. Of all patients, 76% had normalized OSA symptoms at time of the study (ESS: 6.4 ± 5.0) and 98% reported using stimulation therapy every night. Regression analysis revealed an association of current symptoms measured with ESS and response behavior. Hence, patients with normalized daytime sleepiness reported significantly more positive experience across all domains assessed, compared to patients with residual daytime sleepiness. Overall, only 2% of participants reported side effects that made them reduce or discontinue stimulation therapy. The rate of reported side effects was associated with current symptom control under therapy. CONCLUSIONS: Overall patient-reported experience with breathing-synchronized HNS therapy was positive and high satisfaction with the treatment process was observed. Side effects occurred, but rarely affected subjective use of the therapy or satisfaction. Subjective experience and perception are influenced by residual daytime sleepiness with stimulation therapy.

A systematic review on 4D images of the upper airway in patients with OSA.

AIM-BACKGROUND: In the treatment of obstructive sleep apnoea (OSA), oral appliances are now being recognized as a valuable alternative to continuous positive airway pressure (CPAP). Various static imaging techniques of the upper airways allow for assessment of bone and soft tissue structures. However, static images do not capture dynamic airway characteristics. The aim of this paper was to review 4D imaging techniques in patients with OSA. METHODS: PubMed/MEDLINE, Web of Science and Embase were systematically searched for studies published before June 2022. The review was compliant with the PRISMA guidelines. The quality of each eligible study was critically evaluated by all four authors independently. Four unique articles with qualitative analyses were retrieved. All included studies had a clear objective/aim, an appropriate endpoint and sufficiently described eligibility criteria. RESULTS: With dynamic imaging (4D) evaluation of the upper airway, the incidence of upper airway collapsibility due to use of a mandibular advancement device (MAD) was reduced, extraluminal tissue pressure was decreased and the space in the upper airway was increased, notably in the retropalatal and retroglossal areas of the airway. These findings suggest that MADs may be effective for OSA regardless of whether or not the obstruction site is in the velopharynx or oropharynx. However, further investigation of dynamic changes in the upper airway is required to explain the efficacy of OSA treatment and the underlying mechanisms.

Management of sleep-disordered breathing in patients with syndromic hemifacial macrosomia.

PURPOSE: Patients with syndromic hemifacial microsomia (SHFM) are at risk of obstructive sleep apnea (OSA). The aim of the study was to describe the prevalence of OSA and its management, especially in patients with Goldenhar syndrome (GS). METHODS: The respiratory polygraphies and clinical management of 15 patients, aged 2 to 23 years, evaluated at a national reference center, were analyzed. RESULTS: Four (27%) patients had no OSA, 4 (27%) had mild OSA, and 7 (46%), of whom 5 were ≤ 2 years old, had severe OSA. None of the patients had central apneas. Only one patient had alveolar hypoventilation, and another one had nocturnal hypoxemia. Two patients had severe OSA despite prior adenoidectomy or mandibular distraction osteogenesis. Median duration of follow-up was 3.5 years (range 0.5-9 years). None of the patients without OSA or with mild OSA at baseline respiratory polygraphy developed OSA during the follow up. Among the 7 patients with severe OSA, 3 required continuous positive airway pressure or noninvasive ventilation, and one patient required a tracheostomy. CONCLUSION: In conclusion, patients with SHFM are at high risk of severe OSA at any age, underlining the importance of systematic sleep studies to diagnose and evaluate the severity of OSA. Individualized treatment should be privileged, based on a careful examination of the entire upper airway, taking in account potential associated risk factors. All patients with SHFM should be managed by a pediatric expert multidisciplinary medical/surgical team until the end of post pubertal growth.

Determinants of difficult laryngoscopy based on upper airway indicators: a prospective observational study.

BACKGROUND: The main cause of anesthesia-related deaths is the failure to manage difficult airways. Difficult laryngoscopic exposure is a major cause of unsuccessful management of difficult airways. Inadequate preoperative airway assessment hinders the clinical management of difficult airways cases, emphasizing the critical need for accurate identification of difficult airways. Currently, no definitive and reliable indicators are available to predict a difficult airway. Our study aims to predict laryngoscope exposure risk factors by combining ultrasonically measured upper airway anatomic parameters with physical examination indicators. METHODS: Patients aged 18 to 75 years, classified as American Standards Association (ASA) I-III, and scheduled for elective general anesthesia with endotracheal intubation were included. All patients received the upper airway and ultrasonographic measurements. After anesthesia induction, laryngoscope exposure was analyzed using the Cormack-Lehane grading system, with Grades III and IV as indicative of difficult laryngoscopy. Univariate and multivariate logistic regression analyses were performed to identify reliable indicators for predicting difficult laryngoscopy. Receiver Operating Characteristic (ROC) curve analysis was utilized to assess the predictive performance of each indicator. RESULTS: A total of 1120 patients finished the study, with 710 cases found in Grade I laryngoscopic exposure group, 360 cases in Grade II group, and 50 cases in Grade III group. There was no case observed in Grade IV group, thereby resulting in an incidence of difficult laryngoscopy of 4.46%. Univariate logistic regression analysis revealed that several parameters including age, Body Mass Index (BMI), neck circumference, neck mobility, snoring intensity, as well as ultrasound measurements of the pre-epiglottic space and thyromental distance were identified as significant risk factors for difficult laryngoscopy (P < 0.05). Among these, BMI, and neck circumference exhibited notable predictive value, with Area Under The Curve (AUC) values of 0.746 (95%CI 0.649-0.842) and 0.732 (95%CI 0.638-0.827), respectively. Neck mobility was also identified as an independent risk factor for predicting difficult laryngoscopy (P = 0.009) in multivariate logistic regression analysis, with an AUC of 0.672 (0.562-0.782) in the ROC curve. CONCLUSIONS: Our findings revealed a direct correlation between difficult laryngoscopy and age, BMI, neck circumference, neck mobility, snoring intensity, as well as ultrasound measurements of the pre-epiglottic space and thyromental distance. Furthermore, neck mobility was identified as an independent predictive factor. TRIAL REGISTRATION: The trial was registered prior to patient enrollment at clinicaltrials.gov (register no. ChiCTR2100053826, Date of registration: November 30, 2021).

Upper airway stimulation device failure: A 7-year single center experience.

OBJECTIVE: To identify and report a single center experience with upper airway stimulator device-related failures. STUDY DESIGN: Retrospective case series. SETTING: Single tertiary academic center. METHODS: Retrospective data on 352 patients who underwent UAS surgery with an Inspire device from 2016 to 2023 was collected, including demographics, comorbidities, and nature of device failure requiring revision surgery. RESULTS: Out of the 348 patients included in our analysis, 16 (4.6 %) required revision due to device failure, with an average interval of 772 days (∼2 years) between initial implant and revision. Most failures were attributed to respiratory sensing lead damage (n = 11, 68.8 %), resulting in high system impedance and subsequent device malfunction. Lead fracture causes varied, including idiopathic occurrences and potential trauma. Lead migration was noted in one case (6.3 %), where the hypoglossal electrode detached from the nerve. Two patients (12.3 %) required implantable pulse generator (IPG) replacement, one after experiencing trauma and the other due to unclear source of malfunction. One patient (6.3 %) required complete system replacement following high lead impedance and absent tongue motion. The last patient required replacement of both the IPG and respiratory lead after experiencing high lead impedance (6.3 %). CONCLUSION: Respiratory sensing lead fracture emerged as the leading cause of device failure in this cohort, underscoring the need to address this under-reported issue, potentially linked to the time lapse after device implantation.

Comparative analysis of pain outcomes in hypoglossal nerve stimulation: Avoiding the digastric tendon.

OBJECTIVE: Upper airway stimulation effectively treats patients with obstructive sleep apnea, especially among those with low long-term compliance with continuous positive airway pressure. Traditional methods to implant the hypoglossal nerve stimulator involve retraction of the digastric tendon to identify the nerve and improve exposure for stimulator implantation. Transient submental pain and discomfort are known side effects of the procedure. Placement without retraction provides an alternative approach to minimize postoperative pain. This study compares post-operative pain outcomes of patients in whom the digastric tendon was and was not retracted. METHODS: Retrospective chart review of patients who received the hypoglossal nerve stimulation implant at a single institution between 2017 and 2021. A combination of descriptive and qualitative data, including age, gender, comorbidities, and postoperative symptoms are analyzed to characterize patient outcomes resulting from this intraoperative technique. The categorical and continuous variables were analyzed using chi-squared tests and independent t-tests, respectively. RESULTS: Patients report overall satisfaction after implantation and titration. A total of 108 patients underwent HGNS implantation between September 2017 and January 2021 using the aforementioned techniques. 1.69 % of patients experienced postoperative submental pain as compared to 18.37 % prior to the change in technique (p < 0.01). CONCLUSION: Avoidance of digastric tendon retraction in the implantation of the stimulating lead is a safe and effective technique that reduces postoperative pain and discomfort. Our institution has demonstrated an alternative technique for hypoglossal stimulator implantation which improves perioperative outcomes. LAY SUMMARY: Upper airway stimulation is an effective treatment for obstructive sleep apnea. During surgery, the digastric tendon is often moved to identify the nerve and improve access. This study shows that avoiding digastric tendon movement safely reduces postoperative pain and discomfort. LEVEL OF EVIDENCE: III.

Treatment of a floppy epiglottis with upper airway stimulation therapy.

PURPOSE: To evaluate the efficacy of upper airway stimulation therapy in patients with a floppy epiglottis who have experienced continuous positive airway pressure failure or intolerance. METHODS: A retrospective single-center cohort study was conducted. Patients who received an Inspire Upper Airway Stimulation system and had a 1-year follow-up were included. Baseline and one-year in-laboratory polysomnography examinations were performed. Patient characteristics, Epworth Sleepiness Scale scores and upper airway stimulation device settings were collected. RESULTS: A total of 75 patients were included, of whom 10 had a floppy epiglottis. Patients with a floppy epiglottis had a significant therapeutic response to upper airway stimulation therapy, similar to patients without a floppy epiglottis. According to the Sher's success criteria, 90% of patients with a floppy epiglottis and 68% of patients without a floppy epiglottis were responders to therapy (p = 0.149). In the floppy epiglottis group, the apnea-hypopnea index decreased from 35.1 ± 5.5 events/hour to 11.2 ± 11.3 events/hour (95% CI (15.0, 32.9), p < 0.001), similarly in the non-floppy epiglottis group, the decline was from 36.4 ± 8.3 events/hour to 14.4 ± 9.5 events/hour (95% CI (18.6, 25.2), p < 0.001, between groups p = 0.659). Comparable reductions were observed for the other respiratory parameters. CONCLUSION: Treatment of patients with obstructive sleep apnea and a floppy epiglottis can be challenging. Continuous positive airway pressure may aggravate the epiglottis collapse. Upper airway stimulation therapy can be considered an effective alternative treatment option for patients with a floppy epiglottis who have encountered either continuous positive airway pressure failure or intolerance.

Risk of cancer in patients with sleep apnea: comparison of surgery versus CPAP in a long-term follow-up study.

PURPOSE: This study aimed to obtain a comprehensive view of the risk of developing cancer in patients with obstructive sleep apnea (OSA) and to compare this risk between patients receiving continuous positive airway pressure (CPAP) therapy versus upper airway surgery (UAS). METHODS: We used both local data and a global-scale federated data research network, TriNetX, to access electronic medical records, including those of patients diagnosed with OSA from health-care organizations (HCOs) worldwide. We used propensity score matching and the score-matched analyses of data for 5 years of follow-up, RESULTS: We found that patients who had undergone UAS had a similar risk of developing cancer than those who used CPAP [hazard ratio of 0.767 (95% CI 0.559-1.053; P = 0.100)]. CONCLUSION: Analysis of the large data sets collected from HCOs in Europe and globally lead us to conclude that in patients with OSA, neither CPAP nor UAS were associated with the development of cancer better than in non-treated patients.

Clinical effects of twin-block combined with maxillary expansion on the upper airway in adolescents with Class II malocclusion.

BACKGROUND: Class II malocclusion, particularly class II division 1, poses a significant orthodontic challenge with implications for both aesthetics and health. This study aimed to explore the impact of twin-block (TB) combined with maxillary expansion treatment (TB-ME) on upper airway dimensions and inflammatory profiles in adolescents with skeletal Class II Division 1 malocclusion in adolescent. METHODS: Ninety-two eligible patients were randomly assigned to two groups: TB-ME treatment and traditional McLaughlin Bennett Trevisi (MBT) straight-wire orthodontic treatment (Control). Cephalometric lateral X-ray scans were conducted before and after treatment to assess skeletal changes, including SNA, ANB, and SNB angles, which are essential to assess the anteroposterior relationships of the maxilla and mandible to the cranial base. We also measured the upper airway volumes and areas. Concentrations of inflammatory factors including intercellular adhesion molecule 1 (ICAM-1), matrix metallopeptidase 2 (MMP2), and interleukin 8 (IL-8) of gingival crevicular fluid analysis (GCF) were detected by enzyme-linked immunosorbent assay. RESULTS: TB-ME treatment induced significant improvement in cephalometric parameters, including a decrease in SNA and ANB angles and an increase in SNB angle. Upper airway volumes and areas increased significantly in both groups, with TB-ME showing greater improvements. GCF analysis revealed a reduction in ICAM-1, MMP2, and IL-8 concentrations in the TB-ME group compared to the Control group. CONCLUSIONS: TB-ME treatment demonstrates multifaceted improvements in skeletal malocclusion, upper airway dimensions, and inflammatory profiles in adolescents with class II division 1 malocclusion, showing the promise of TB-ME in addressing the complexities associated with class II malocclusion.