During Drug-induced Sleep Endoscopy Research Articles

Expiratory Velopharyngeal Obstruction: Sleep Endoscopy-Guided Treatment Strategies to Prevent Oral Breathing During Sleep.

Obstructive sleep apnea (OSA) is a prevalent disorder, with oral breathing influencing its severity. Expiratory velopharyngeal obstruction (EVO), observed during drug-induced sleep endoscopy (DISE), may contribute to oral breathing in OSA patients. EVO results in obstruction between the pharynx and nasal cavity during expiration. This study aims to identify factors associated with positive EVO during DISE. Case series. Tertiary Medical Center. Seventy-two OSA patients underwent clinical evaluation, polysomnography, and DISE, utilizing interventions like intraoral negative airway pressure (iNAP), mouth closure, and oral appliances (OAs) in supine positions with head rotation. The findings, classified under velopharynx, oropharynx, tongue base, epiglottis, included the presence of EVO. The results demonstrated that interventions including mouth closure and iNAP were associated with increased observation of EVO (43.1% and 34.7%) compared to OA (20.1%). However, head rotation was associated with decreased presence of EVO during DISE compare to supine (26% vs35.8%). Noticeably, per 1 year increase of age was associated with an increased odds of EVO (odds ratio: 1.03, 95% confidence interval: 1.01-1.06). However, no other baseline characteristics were significantly associated the odds of EVO. Our study reveals the effectiveness of head rotation and OA in reducing EVO and improving mouth breathing in OSA patients, offering valuable insights for future treatment strategies.

The influence of different application patterns of propofol on the sedation courses during drug-induced sleep endoscopy.

The course of sedation during drug-induced sleep endoscopy (DISE) depends on the application pattern of the sedative drug. The depth of sedation should imitate light and deep sleep as well. Moreover, there should be as many breathing cycles as possible available for observation during light and deep sedation. The aim of the study was to evaluate different rates of propofol application with respect to the achieved depth and length of the course of sedation. Sixty-three consecutive patients with obstructive sleep apnea and/or snoring undergoing DISE were randomly sedated by propofol perfusion at seven different application patterns: 14, 16, 18, 19, 20, 22 mg/kg/h (0.233, 0.267, 0.3, 0.317, 0.333, 0.367 mg/kg/min) per perfusor and individual bolus application 10 mg each. Sedation depth was monitored by BiSpectral Index™ (BIS). The influence of baseline parameters and the courses of sedation were analyzed. The application rate was the only factor that influenced the depth of sedation. Basic parameters (gender, age, body mass index, apnea-hypopnea index) had no influence on the depth of sedation. The sedation depth was dependent on the rate of propofol application. Regimes at 14 and 16 mg/kg/h as well as bolus application did not reach BIS levels below 50 representing deep sleep. Propofol doses of more than 20 mg/kg/h led to rapid decreases of sedation levels below deep sleep niveau. Propofol rates between 18 and 20 mg/kg/h enable BIS levels below 50 representing deep sleep and providing enough breathing cycles for observation. Lower application rates of propofol provide slower courses of sedation and shallower depths of sedation. A rate of 14 mg/kg/h might be appropriate to reach a sedation plateau at light sleep. A rate of 18 mg/kg/h leads to a sedation, corresponding to deep sleep. The combination of both rates might be a suitable pattern for performing sedation-controlled DISE. 2: Randomized trial.

The Repeatability of Pharyngeal Opening Pressure Under Drug-Induced Sleep Endoscopy.

Pharyngeal opening pressure (PhOP) is a measure of upper airway collapsibility that can be obtained during drug-induced sleep endoscopy (DISE) using a continuous positive airway pressure (CPAP) titration. However, the stability of PhOP over the course of sedation during DISE remains unclear. This study aims to compare repeat measures of PhOP over the course of DISE. Single arm prospective study. Single tertiary care institution. Patients had 2 CPAP titrations while undergoing DISE. Collected data included patient demographics, PhOP, patient sedation index (PSI), and duration of and between CPAP titrations. t Tests, test-retest coefficient analysis, and repeated measures correlation were performed. Twenty-five patients completed the study between 2022 and 2023 with 22 patients having sedation depth (PSI) recording. Most were male (76%), obese (average body mass index: 30.24 kg/m2), with severe obstructive sleep apnea (average apnea-hypopnea index: 39.8 events/hr). Test-retest analysis showed good-excellent correlation between PhOP values (intraclass correlation coefficient = 0.892, P < .0001, n = 25). Average time between CPAP titrations was 15 minutes to 6 seconds. Over that time, PhOP increased by an average of 0.72 cmH2O (P = .06, n = 25) and PSI decreased by 9.5 units (P = .01, n = 22). Repeated measures correlation showed a weak negative correlation between PhOP and PSI (r = -.45, P = .03, n = 22). The results showed repeatability of PhOP values over the course of DISE. When adjusted for sedation depth (PSI), deeper sedation was weakly associated with greater PHOP. However, the magnitude of this change was small and we conclude that PhOP remains relatively stable over the course of DISE (Effects of Lung Volume on Upper Airway Patency During DISE [DISE-Pulm], NCT05350332, clinicaltrials.gov).

Association Between Soft Tissue Measures From Computed Tomography and Upper Airway Collapsibility on Drug-Induced Sleep Endoscopy.

Positive airway pressure (PAP) titration during drug-induced sleep endoscopy (DISE) provides objective measures of upper airway collapsibility. While skeletal measurements relate to collapsibility measures on DISE, the influence of soft tissue dimensions on upper airway collapsibility is not known. We analyzed the relationship of measures of upper airway soft tissue volumes, specifically soft palate, pharyngeal lateral walls, and tongue, with metrics of collapsibility. Cross-sectional analysis from a prospective cohort. Academic medical center. Patients seeking PAP alternative therapies for obstructive sleep apnea (OSA) underwent standardized supine computed tomography (CT) acquisition and DISE protocols. The CT analysis primarily focused on soft tissue volumes and, secondarily, on airway and skeletal volumetric measures. DISE with PAP administration (DISE-PAP) enabled the determination of the pressure at which inspiratory airflow first commenced (pharyngeal critical pressure, PcritA) and the pressure at which inspiratory flow limitation was abolished (pharyngeal opening pressure, PhOP). Both unadjusted and adjusted correlation analyses were performed to understand the relationship between upper airway anatomy and either PcritA or PhOP. One hundred thirty-nine subjects completed both CT and DISE-PAP. On average, patients were male (70.5%), white (84.2%), middle-aged (56.6 ± 13.5 years), and overweight (29.6 ± 4.7 kg/m2), with moderate-severe apnea-hypopnea index (29.7 ± 21.3 events/h). Adjusted for age, sex, body mass index, and skeletal volumes, soft palate, and lateral pharyngeal wall volumes were not associated with PhOP or PcritA, but a larger tongue was associated with more positive PhOP (⍴ = 0.20, P = .02), and more positive PcritA (⍴ = 0.16, P = .07). Exploratory analyses revealed smaller minimum cross-sectional retropalatal area and intramandibular volume were also associated with increased collapsibility measures. After controlling for clinical factors and skeletal volume, greater tongue volume was associated with more severe collapsibility during DISE. These results, in concert with previous work, suggest that greater tongue volume in a smaller skeletal dimensions contribute to the severity of airway collapsibility, a key driver of OSA pathogenesis.

Polysomnographic airflow shapes and site of collapse during drug-induced sleep endoscopy.

Differences in the pharyngeal site-of-collapse influences efficacy of non-CPAP therapies for obstructive sleep apnoea (OSA). Notably, complete concentric collapse at the palate (CCCp) during drug-induced sleep endoscopy (DISE) is associated with reduced efficacy of hypoglossal nerve stimulation, but CCCp is currently not recognisable using polysomnography. Here we develop a means to estimate DISE-based site-of-collapse using overnight polysomnography. 182 OSA patients provided DISE and polysomnography data. Six polysomnographic flow-shape characteristics (mean during hypopnoeas) were identified as candidate predictors of CCCp (primary outcome variable, N=44/182), including inspiratory skewness and inspiratory scoopiness. Multivariable logistic regression combined the six characteristics to predict clear presence (N=22) versus absence (N=128) of CCCp (partial collapse and concurrent tongue-base collapse excluded). Odds ratios for actual CCCp between predicted subgroups were quantified after cross-validation. Secondary analyses examined complete lateral wall, tongue-base, or epiglottis collapse. External validation was performed on a separate dataset (Ntotal=466). CCCp was characterised by greater scoopiness (β=1.5±0.6 per 2SD, multivariable estimate±se) and skewness (β=11.4±2.4) compared to non-CCCp. Odds ratio [95%CI] for CCCp in predicted positive versus negative subgroups was 5.0[1.9-13.1]. The same characteristics provided significant cross-validated prediction of lateral wall (OR=6.3[2.4-16.5]), tongue-base (3.2[1.4-7.3]), and epiglottis (4.4[1.5-12.4]) collapse. CCCp and lateral wall collapse shared similar characteristics (skewed, scoopy), diametrically opposed to tongue-base and epiglottis collapse characteristics. External validation confirmed model prediction. The current study provides a means to recognise patients with likely CCCp or other DISE-based site-of-collapse categories using routine polysomnography. Since site-of-collapse influences therapeutic responses, polysomnographic airflow shape analysis could facilitate precision site-specific OSA interventions.

The Prevalence of Sentinel Central Events (SCent) During Drug-Induced Sleep Endoscopy.

With the recent addition of airflow and respiratory effort channels, our group has observed central and mixed apnea events during drug-induced sleep endoscopy (DISE). We measured the frequency and timing of sentinel central and/or mixed events (SCents), as well as assessed for differences in velum, oropharynx, tongue, and epiglottis (VOTE) classification compared to obstructive events. Prospective single-cohort study. Tertiary Care Academic Medical Center. Patients underwent DISE between June 2020 and November 2022. Nasal airflow, thoracoabdominal effort belt signals, and videoendoscopy were simultaneously captured. Demographics, sleep study, and DISE data were compared among patients with and without SCents using Student's T tests or χ2 tests. On average, the cohort (n = 103) was middle-aged (53.5 ± 12.1 years), overweight (body mass index of 29.7 ± 5.3 kg/m2), and had severe obstructive sleep apnea (apnea-hypopnea index of 30.7 ± 18.7 events/h). Forty-seven patients (46%) were found to have at least 1 SCent. Among those with SCent, 45 (95.7%) transitioned to obstructive pathology after an average of 7.91 ± 2.74minutes, with at least 95% of patients expected to do so within 12.57minutes. Twenty-nine out of 47 patients (61.2% [95% confidence interval: 46.4.9%, 75.5%]) with SCent had meaningful differences between central/mixed and obstructive VOTE scores. Central events were present in almost half of our cohort. At least 95% of patients were expected to transition to obstructive events within 12 to 13minutes of propofol initiation. In addition, over half of patients demonstrate significantly different VOTE scores between central and obstructive events. These factors should raise awareness of central events and scoring passive apneas during DISE and consider delaying VOTE scoring.

The impact of nasal use of azelastine and mometasone furoate on drug-induced sleep endoscopy.

Endoscopic evaluation becomes difficult when excessive secretion/hypersalivation occurs in the upper airway. Intranasal corticosteroids and antihistamines reduce symptoms of rhinorrhea and nasal congestion. For this reason, in our study, we aimed to examine the effects of mometasone furoate and azelastine on both the amount of secretion and upper airway obstruction in terms of possible benefits during drug-induced sleep endoscopy (DISE). A total of 92 patients participated in the study [69 (75%) were males and 23 (25%) were females]. Three groups in Group 1 used intranasal mometasone furoate for 30 days, Group 2 used intranasal azelastine for 30 days, and Group 3 did not use any nasal spray for 30 days. Then, DISE was performed on all patients on the 30th day. Upper airway obstructions detected in DISE were interpreted according to the VOTE classification. Furthermore, the amount of secretion and patients' tolerance levels observed during DISE were also assessed. Multilevel obstruction was detected in 94.5% of all patients participating in the study. Tolerance was poor in 18 (19.5%) of the patients participating in the study. Better DISE tolerance was determined in the female gender. DISE tolerance was also better in underweight and normal-weight patients (BMI < 25). This study first investigated nasal mometasone furoate and azelastine on DISE. This study showed that prior use of nasal mometasone furoate or azelastine before DISE did not affect the amount of secretion, tolerance level, severity, and configuration of obstruction.

Simethicone use in drug-induced sleep endoscopy improves visibility.

To assess the effect of simethicone, a defoaming agent, on improving visibility during drug-induced sleep endoscopy (DISE) in obstructive sleep apnea (OSA). The study was a retrospective case-series study on patients with OSA who failed positive airway pressure (PAP) treatment. Patient parameters were recorded including age, BMI, neck and abdominal circumference, and apnea-hypopnea index (AHI). Comparisons were made between DISE procedures performed with and without the administration of simethicone. Visibility during DISE was independently graded by two surgeons, and inter-rater reliability was assessed. Simethicone significantly improved DISE visibility (p = 0.03). "Best visibility" was achieved in 55% of cases with simethicone compared to 27% without simethicone (p = 0.02). Sub-analysis showed that only simethicone administration had a significant effect on visibility (p = 0.02). Inter-rater reliability between the grading surgeons was strong (Cohen-Kappa score 0.7, p < 0.001). The findings suggest that simethicone enhances DISE visibility for OSA surgical planning. Further research should explore optimizing simethicone administration timing and the potential clinical implications for surgical outcomes and patient care.

Quantitative Measurement of Pharyngeal Dimensions During Drug-induced Sleep Endoscopy for Oral Appliance Outcome.

To quantitatively investigate the effect of mandibular advancement devices (MADs) on pharyngeal airway dimensions in a transverse plane as measured during drug-induced sleep endoscopy (DISE). Data from 56 patients, treated with MAD at 75% maximal protrusion and with baseline Apnea-Hypopnea Index ≥10 events/h, were analyzed. For each patient, three snapshots were selected from DISE video footage at baseline, with MAD presence, and during chin lift, resulting in 498 images (168/168/162, baseline/MAD/chin lift). Cross-sectional areas, anteroposterior (AP) and laterolateral (LL) dimensions on both retroglossal and retro-epiglottic levels were measured. To define the effect of MAD and chin lift on pharyngeal dimensions, linear mixed-effect models were built. Associations between MAD treatment response and pharyngeal expansion (MAD/chin lift) were determined. Significant differences were found between retroglossal cross-sectional areas, AP, and LL dimensions at baseline and with MAD presence. At a retro-epiglottic level, only LL dimensions differed significantly with MAD presence compared to baseline, with significant relation of LL expansion ratio to treatment response (p = 0.0176). After adjusting the response definition for the sleeping position, greater retroglossal expansion ratios were seen in responders (1.32 ± 0.48) compared to non-responders (1.11 ± 0.32) (p = 0.0441). No significant association was found between response and pharyngeal expansion by chin lift. Our observations highlight the additional value of quantitative pharyngeal airway measurements during DISE with MAD presence in evaluating MAD treatment outcome. These findings demonstrate an increase in retroglossal airway dimensions during DISE, with MAD presence, and more pronounced increase in retroglossal expansion ratios in MAD treatment responders compared to non-responders after sleeping position correction. 3 Laryngoscope, 133:3619-3627, 2023.

Proposal of a Full Digital Workflow for a Bite Fork to Assess Mandibular Advancement during Drug-Induced Sleep Endoscopy (DISE) for Obstructive Sleep Apnea

(1) Background. Drug-induced sleep endoscopy (DISE) is currently regarded as the gold standard diagnostic procedure to assess the site(s) of upper airway collapse in subjects affected by Obstructive Sleep Apnea Syndrome (OSAS). During DISE, a jaw thrust maneuver is performed to advance the mandible and to predict the effectiveness of outcomes of treatment with mandibular advancement devices (MADs). However, the maneuver is not predictable and could be influenced by specific patients’ anatomical/functional conditions. The aim of this work is to propose a full-digital workflow for customizing an individual mandibular advancement fork, usable by otorhinolaryngologists during DISE. (2) Materials. Two patients with a diagnosis of mild-to-moderate OSAS (AHI ≥ 5 to ≤30/h of sleep) underwent orthodontic examination to verify the usability of the MAD. Intra-oral scans and registration were performed, including bite registration with 65% of mandibular advancement. The latter measurement was used as a reference to design a 3D-printed fork for DISE, as well as for the future MAD. Both patients underwent DISE in the operating room in the presence of an anesthesiologist, otolaryngologist, orthodontic specialist and neurophysiopathology technician. (3) Results. In the intraoperative polysomnography recording, during sleep, the presence of obstructive apnea was confirmed based on respiratory parameters (PNG1, PNG2, PNG3) with associated desaturation and increased muscle activities on PNG4 (mylohyoid muscle), EMG1 (right masseter muscle) and EMG2 (left masseter muscle). With the advancement fork in place, the immediate improvement effect on all respiratory parameters with normal saturation values and the complete suppression of masseter muscles were observed. Accordingly, both patients were considered potential good-responders to the MAD treatment. (4) Conclusions. The preliminary data shown are encouraging and would suggest that the fork represents a stable reference for the otorhinolaryngologist to evaluate the airway patency within the physiological range of movement. The efficiency of the work-flow from data registration to the DISE procedure and laboratory process represent two significant advantages that justify the integration of a digital system in the management of patients affected by OSAS.

0427 Airway Pressures Define Collapsibility of Specific Pharyngeal Sites of Obstruction during Drug-induced Sleep Endoscopy

Abstract Introduction Obstructive sleep apnea (OSA) is characterized by repetitive episodes of pharyngeal obstruction at one or more collapse sites. Multilevel collapse is a negative predictive factor for PAP-alternative surgical treatments. Pharyngeal manometry during drug-induced sleep endoscopy (DISE) permits an objective evaluation of anatomical obstruction sites and mechanisms, and may play a role in patient selection for PAP alternative therapies. We hypothesized that patients with multilevel collapse would have primary velopharyngeal collapse and secondary, downstream sites. Methods This prospective cohort of twenty consecutive patients with diagnosed OSA underwent DISE with nasal airflow monitoring and pharyngeal manometry. Two pressure catheters were placed at the (1) distal margin of the soft palate (Pus) and (2) retroepiglottic space (Pds). We sought to delineate site(s) of collapse by evaluating dissociations in airflow and air pressure during inspiratory flow limitation and/or complete obstruction. The primary site of collapse was defined by the initial segment at which inspiratory airflow and pressure dissociated (the critical pressure, Pcrit). Secondary site(s) were defined as the pressure at which the Pus and/or Pds signals subsequently dissociated (beyond the initial point of maximal flow). Results Twenty-one patients were evaluated of which signal quality and catheter placement in twenty were sufficient for analysis. Participants were elderly (58.3±14.3yrs, mean±SD), overweight (BMI 28.7±2. kg/m2), and had moderate-severe OSA (AHI 28.2±14.2 events/hour). Six patients had a single site of collapse, of which one was naso-palatal (Pcrit -2.6cmH2O) and five were infra-palatal (mean Pcrit -1.3cmH2O). In the patients with multilevel collapse (N=14), all had primary naso-palatal collapse (mean Pcrit 0.17±2.0cmH2O) and secondary infra-palatal sites of collapse (mean Pcrit -11.7±5.8cmH2O). Pcrit differed between the primary and secondary site by 11.9±6.5cmH2O (p&amp;lt; 0.01). Conclusion These findings suggest that single-site pharyngeal collapse is usually infra-palatal. In contrast, multilevel collapse is primarily due to velopharyngeal collapse with varying degrees of instability in downstream pharyngeal segments. When secondary infra-palatal sites readily collapse with minimal additional respiratory effort, laxity of the tongue and/or lateral walls may be strongly implicated in the pathogenesis of pharyngeal obstruction. Future studies can utilize pharyngomanometry to further target specific pharyngeal structures for OSA therapy. Support (if any) National Institutes of Health 1R01HL144859 (PIs: Schwartz, Dedhia)

Efficacy of high-flow nasal oxygen during drug-induced sleep endoscopy in patients with obstructive sleep apnea.

High-flow nasal oxygenation (HFNO) can provide a low level of continuous positive airway pressure and alveolar recruitment. We aimed to compare the efficacy of pre-oxygenation with HFNO and low-flow nasal oxygenation (LFNO) during drug-induced sleep endoscopy (DISE). In the LFNO group, preoxygenation was performed for 10 min at 3 L·min-1. In the HFNO group, preoxygenation was performed for 10 min at 30 L·min-1 at a fraction of inspired oxygen of 100% using the Optiflow device. From the start of sedative administration to the end of DISE, vital signs were monitored continuously. The primary outcome was the lowest oxygen saturation (SpO2) during DISE. Of 24 patients enrolled, 12 were randomly assigned to the LFNO and 12 to the HFNO groups. Theprevalence of hypoxia events was 75% in the LFNO group and 58% in the HFNO group. The difference in lowest oxygen saturation between the two groups was not significant between the two groups (P=0.665). The lowest SpO2 during all procedures was comparable between the two groups (86.8 ± 6.5% in the LFNO group and 87.2 ± 8.0% in the HFNO group; P=0.912). The findings suggest thatHFNO may not be superior to LFNO as a preoxygenation tool to prevent hypoxia during DISE.

Sleep Endoscopy with Positive Airway Pressure: A Method for Better Compliance and Individualized Treatment of Patients with Obstructive Sleep Apnea.

In this study, we aimed to observe the effects of positive airway pressure (PAP) on individual levels of obstruction during drug-induced sleep endoscopy (DISE) of the upper airways (UA), to evaluate at which pressures the obstruction disappeared or worsened, and to identify cases in which PAP was ineffective. This prospective study was conducted from June 2018 to June 2022. PAP testing was performed during DISE in patients with moderate and severe OSA. The pressure was gradually increased over the range from 6.0 to 18.0 hPa. Our findings were evaluated using the VOTE classification. The examination was performed in 56 patients, with a median apnea-hypopnea index (AHI) of 26.4. Complete obstruction of the soft palate was observed in 51/56 patients (91%), oropharyngeal obstruction in 15/56 patients (27%), tongue base obstruction in 23/56 patients (41%), and epiglottic collapse in 16/56 patients (29%). PAP was most effective in cases of complete oropharyngeal obstruction, and least effective in cases of epiglottic collapse, where it was ineffective in 11/16 patients. DISE with PAP is a simple diagnostic method that can be helpful for identifying anatomic and dynamic reasons for PAP intolerance. The main indication is ineffective PAP treatment.

Palatal Coupling Maneuvers Do Not Predict Hypoglossal Nerve Stimulator Treatment Efficacy.

Maneuvers during drug-induced sleep endoscopy (DISE), for patients with obstructive sleep apnea (OSA), have been used as predictors for success with oral appliances. Hypoglossal nerve stimulation (HGNS) promotes opening at the velum through palatoglossus coupling. In this study, we evaluate maneuvers during DISE as predictors for HGNS treatment efficacy. We evaluated patients undergoing HGNS between November, 2014 and February, 2021. We assessed maneuvers including jaw thrust and chin lift during preoperative DISE. The impact of tongue base and palatal opening during these maneuvers were rated from 1 to 4 (1: no improvement, 2: mild improvement, 3: moderate improvement, 4: significant improvement). Patients were grouped by a score of 1-2 (weak response) or 3-4 (strong response). Apnea hypopnea index (AHI) change was calculated from the difference between preoperative and postoperative sleep study. One hundred and seventy one patients were included. With jaw thrust, there was no significant difference in AHI change between patients with weak or strong response at the palate (n=68 vs. 94, 9.5 vs. 13.6, p=0.21) or tongue base (n=24 vs. 138, 16.6 vs. 11.3, p=0.24). On chin lift, there was no significant difference at the palate (n=82 vs. 18, 13.9 vs. 11.4, p=0.63) or tongue base (n=92 vs. 72, 10.8 vs. 14.6, p=0.24). On multiple linear regression analysis, lower body mass index, higher preoperative AHI, and higher preoperative oxygen nadir were associated with a larger AHI change. Palatal coupling maneuvers during DISE are not predictive of AHI change with HGNS. Findings using these maneuvers should not preclude HGNS candidacy. 3 Laryngoscope, 133:431-436, 2023.

An interim oral appliance as a screening tool during drug-induced sleep endoscopy to predict treatment success with a mandibular advancement device for obstructive sleep apnea.

PurposePrevious studies have shown a wide range of efficacy (29 to 71%) of a mandibular advancement device (MAD) in the treatment of obstructive sleep apnea (OSA). Currently, the ability to preselect suitable patients for MAD therapy based on individual characteristics related to upper airway collapsibility is limited. We investigated if the use of non-custom interim MAD during drug-induced sleep endoscopy (DISE) could be a valuable screening tool to predict MAD treatment outcome.MethodsIn a single-center prospective study including a consecutive series of patients with OSA, we compared DISE outcomes with a MAD in situ with polysomnography results after 3 months of using the same MAD that was used during DISE.ResultsOf 41 patients who completed the study, the median apnea–hypopnea index (AHI) was 16.0 events/h [IQR 7.4–23.4]. Respiratory outcomes on polysomnography, including apnea index (AI), total AHI, AHI in supine position, and oxygen desaturation index, all significantly improved after 3 months of MAD treatment. With complete improvement of the upper airway obstruction with the MAD in situ during DISE in supine position, patients were 6.3 times more likely to be a responder to MAD treatment compared to patients with a persisting complete obstruction, although not statistically significant (OR 6.3; 95%CI 0.9–42.7; p = 0.060).ConclusionThe potential predictive value with regard to MAD therapy outcomes of the use of an interim MAD during DISE would be an important finding, since the prediction of MAD therapy outcome is of great clinical and scientific interest. A study with a larger cohort should be performed to further investigate our findings.

Multimodal phenotypic labelling using drug-induced sleep endoscopy, awake nasendoscopy and computational fluid dynamics for the prediction of mandibular advancement device treatment outcome: a prospective study.

Mandibular advancement device (MAD) treatment outcome for obstructive sleep apnea (OSA) is variable and patient dependent. A global, clinically applicable predictive model is lacking. Our aim was to combine characteristics obtained during drug-induced sleep endoscopy (DISE), awake nasendoscopy, and computed tomography scan-based computational fluid dynamic (CFD) measurements in one multifactorial model, to explain MAD treatment outcome. A total of 100 patients with OSA were prospectively recruited and treated with a MAD at fixed 75% protrusion. In all, 72 underwent CFD analysis, DISE, and awake nasendoscopy at baseline in a blinded fashion and completed a 3-month follow-up polysomnography with a MAD. Treatment response was defined as a reduction in the apnea-hypopnea index (AHI) of ≥50% and deterioration as an increase of ≥10% during MAD treatment. To cope with missing data, multiple imputation with predictive mean matching was used. Multivariate logistic regression, adjusting for body mass index and baseline AHI, was used to combine all potential predictor variables. The strongest impact concerning odds ratios (ORs) was present for complete concentric palatal collapse (CCCp) during DISE on deterioration (OR 28.88, 95% confidence interval [CI] 1.18-704.35; p=0.0391), followed by a C-shape versus an oval shape of the soft palate during wakefulness (OR 8.54, 95% CI 1.09-67.23; p=0.0416) and tongue base collapse during DISE on response (OR 3.29, 95% CI 1.02-10.64; p=0.0464). Both logistic regression models exhibited excellent and fair predictive accuracy. Our findings suggest DISE to be the most robust examination associated with MAD treatment outcome, with tongue base collapse as a predictor for successful MAD treatment and CCCp as an adverse DISE phenotype.

0744 A Comparison of Visual and Physiologic Assessments of Upper Airway Collapse during Drug-Induced Sleep Endoscopy (DISE)

Abstract Introduction The VOTE score, critical closing pressure (Pcrit), and therapeutic CPAP levels are assessments that quantify upper airway collapse by either subjective visual scoring or objective pressure-flow analysis. We hypothesized that there would be an association between collapse severity and physiologic metrics (VOTE versus Pcrit and PAP levels, respectively) acquired during drug-induced sleep endoscopy (DISE). Methods This prospective cohort study evaluated 100 consecutive patients with obstructive sleep apnea (OSA) who underwent DISE with application of nasal positive airway pressure between June 3rd, 2020 and June 11th, 2021. Patients were assigned a VOTE score of 0, 1, or 2 indicating no collapse, partial collapse, or complete collapse at the velum, oropharynx, tongue base, and epiglottis, respectively. We assessed two metrics of pharyngeal collapsibility with progressive increases in nasal pressure: (1) the pressure at which inspiratory airflow commences (critical pressure, Pcrit), and (2) the pressure at which inspiratory flow limitation is abolished (pharyngeal opening pressure, PhOP). Our analysis examined the association between the composite VOTE score [0-8 units] and collapsibility metrics. Results Ninety-one patients met inclusion criteria for VOTE scoring; of these, 87 were included for PhOP analysis and 79 for Pcrit analysis. The cohort was 76% male, mean (SD) age was 54.7 (14.1) years, body-mass index was 29.7 (4.9), and AHI was 30.3 (20.9). Composite VOTE score was positively associated with Pcrit (β = 0.88 ± 0.38 cm H2O per unit, standardized estimate = 0.26, p=0.023). We found no significant association between the composite VOTE score and PhOP (β = 0.57 ± 0.40 cm H2O per unit, standardized estimate = 0.15, p=0.162). Conclusion Our findings suggest that visual and physiological assessments of upper airway collapsibility provide both overlapping and complementary information in characterizing upper airway mechanics. Measures of pharyngeal collapsibility during DISE can be used to model the ultimate impact of therapeutic maneuvers on OSA. Future studies investigating the utility of each assessment both in isolation and in combination for predicting OSA therapy outcomes are indicated. Support (If Any) National Institutes of Health: 1R01HL144859

A Protocol for Propofol-Infusion Drug-Induced Sleep Endoscopy.

The objective of this study was to outline a protocol utilizing propofol infusion without an initial bolus during drug-induced sleep endoscopy (DISE). We define normative values for final propofol infusion rate (Pfinal ) during DISE and sedation depth values at Pfinal . Retrospective chart review. Tertiary academic hospital. A review of patients with obstructive sleep apnea who underwent DISE between 2016 and 2020 was performed. The following patient data were recorded: demographics; DISE procedure details, including Pfinal , time to Pfinal , frequency and cadence of infusion rate changes, depth of sedation as measured by Bispectral Index and SedLine values, and hemodynamics; and polysomnography details including apnea-hypopnea index severity and minimum oxygen saturation. A mixed linear model adjusted for age and body mass index was performed for the analysis of effects on Pfinal . Pearson correlation coefficients determined the strength of association between depth of sedation measured and pattern of collapse on DISE and Pfinal . There were 246 patients who met inclusion criteria. Pfinal resembled a normal distribution (mean ± SD, 156.44 ± 26.69 mcg/kg/min; median, 150 mcg/kg/min). Analysis demonstrated that Pfinal was influenced by male sex, current smoker status, time to Pfinal , and number of propofol dose changes (P < .05). Depth of sedation categories measured differently between Bispectral Index and SedLine (55-65 vs 45-55, P < .001). The pattern including severity of collapse on DISE was not associated with Pfinal (P > .05). No patients required intra- or postoperative respiratory support beyond oxygen via nasal canula. We describe a propofol slow-infusion DISE protocol that demonstrates safe and reproducible outcomes.

Is there an association between EMG activity and temporomandibular disorders during orthotic mandibular advancement in sleep apnea patients undergoing DISE?

ABSTRACT Objective To detect whether myotatic reflex activation of masticatory muscles during drug-induced sleep endoscopy (DISE) can be an indirect marker for temporomandibular disorder (TMD) in patients suffering from obstructive sleep apnea (OSA). Methods OSA patients were prospectively recruited and underwent a complete TMD examination prior to undergoing DISE with the addition of electrodes applied over masticatory muscles. A positive activation of myotatic reflex was considered in case of an increase in muscle tone of at least 50%. Results Of the 41 patients included, 48.8% presented activation of myotatic reflex. Of these patients, 45% presented a TMD diagnosis, 40% presented pain at masticatory muscles palpation, and 15% did not report pain during clinical examination. Conclusion An increase in EMG activity during mandibular advancement is not associated with TMD presence, but it can be an indirect marker of pain in the orofacial area in OSA patients.

Myofunctional assessment for obstructive sleep apnea and the association with patterns of upper airway collapse: a preliminary study.

ObjectivesTo organize an assessment instrument with questionnaires and myofunctional orofacial/oropharyngeal assessment for OSA patients and correlate it with the upper airway obstructive site detected during drug-induced sleep endoscopy (DISE).Material and Methods29 OSA patients aged 22-65 years with an indication to undergo DISE to evaluate an alternative treatment to PAP and signed the consent form. Patients over 65 years old with maxillofacial deficiency and BMI>30 were excluded. The subjects answered the Pittsburgh, Berlin (snore), and Epworth questionnaires. The myofunctional orofacial/oropharyngeal assessment comprised soft palate, palatine pillars, and uvula (structure and mobility), tonsils (size), mandible (bony bases), hard palate (depth and width), tongue (posture, volume, width, and height), floor of mouth (mylohyoid), tongue suction and sustaining (mobility), “lowering of the back of the tongue” (stimulus), which were scored by three speech-language pathologists with expertise. DISE was scored according to VOTE classification. The statistical analysis (t-test) compared groups without and with obstruction in VOTE with questionnaires and myofunctional orofacial/oropharyngeal assessment.ResultsThe following were significantly different: snoring frequency (p=0.03) with VOTE/velopharynx; intensity (p=0.02) and frequency of snoring (p=0.03) with VOTE/lateral wall of oropharynx; suction the tongue and sustain (p=0.02) with VOTE/velopharynx; hard palate depth (p=0.02) and width (p=0.05) with obstruction VOTE/epiglottis; tonsils volume (p=0.05) with VOTE/epiglottis; tongue posture (p=0.00) with obstruction VOTE/epiglottis; floor of the mouth (p=0.02) with VOTE/epiglottis.ConclusionHigher snoring frequency and intensity was observed in patients with obstruction at the velopharynx and oropharyngeal lateral wall. Obstruction at the velopharynx was associated with poor tongue ability to suck the tongue against the hard palate. Obstruction at the epiglottis had structural and functional associations, including the oropharyngeal lateral wall, affected by the palatine tonsils size, depth and width of the hard palate, tongue position, and flaccidity of the floor of mouth. Considering that this is a preliminary study, the data should be carefully verified and not generalized.