Joachim T. Maurer

Upper airway stimulation for obstructive sleep apnea

BACKGROUND Obstructive sleep apnea is associated with considerable health risks. Although continuous positive airway pressure (CPAP) can mitigate these risks, effectiveness can be reduced by inadequate adherence to treatment. We evaluated the clinical safety and effectiveness of upper-airway stimulation at 12 months for the treatment of moderate-to-severe obstructive sleep apnea. METHODS Using a multicenter, prospective, single-group, cohort design, we surgically implanted an upper-airway stimulation device in patients with obstructive sleep apnea who had difficulty either accepting or adhering to CPAP therapy. The primary outcome measures were the apnea-hypopnea index (AHI; the number of apnea or hypopnea events per hour, with a score of ≥15 indicating moderate-to-severe apnea) and the oxygen desaturation index (ODI; the number of times per hour of sleep that the blood oxygen level drops by ≥4 percentage points from baseline). Secondary outcome measures were the Epworth Sleepiness Scale, the Functional Outcomes of Sleep Questionnaire (FOSQ), and the percentage of sleep time with the oxygen saturation less than 90%. Consecutive participants with a response were included in a randomized, controlled therapy-withdrawal trial. RESULTS The study included 126 participants; 83% were men. The mean age was 54.5 years, and the mean body-mass index (the weight in kilograms divided by the square of the height in meters) was 28.4. The median AHI score at 12 months decreased 68%, from 29.3 events per hour to 9.0 events per hour (P<0.001); the ODI score decreased 70%, from 25.4 events per hour to 7.4 events per hour (P<0.001). Secondary outcome measures showed a reduction in the effects of sleep apnea and improved quality of life. In the randomized phase, the mean AHI score did not differ significantly from the 12-month score in the nonrandomized phase among the 23 participants in the therapy-maintenance group (8.9 and 7.2 events per hour, respectively); the AHI score was significantly higher (indicating more severe apnea) among the 23 participants in the therapy-withdrawal group (25.8 vs. 7.6 events per hour, P<0.001). The ODI results followed a similar pattern. The rate of procedure-related serious adverse events was less than 2%. CONCLUSIONS In this uncontrolled cohort study, upper-airway stimulation led to significant improvements in objective and subjective measurements of the severity of obstructive sleep apnea. (Funded by Inspire Medical Systems; STAR ClinicalTrials.gov number, NCT01161420.).

Implanted upper airway stimulation device for obstructive sleep apnea

Previous feasibility studies have shown that electrical stimulation of the hypoglossal nerve can improve obstructive sleep apnea (OSA). The current study examined the safety and preliminary effectiveness of a second generation device, the Upper Airway Stimulation (UAS) system, and identified baseline predictors for therapy success.

European position paper on drug-induced sedation endoscopy (DISE)

BackgroundAlthough drug-induced sedation endoscopy (DISE) represents the most widespread diagnostic tool for upper airway endoscopic evaluation of snoring and obstructive sleep apnea hypopnea syndrome (OSAHS), many controversies exist about how to perform the sedation, the indications for DISE, and how to report DISE findings. The present position paper reports on a consensus as proposed by a group of European experts in the field of DISE after discussion during a recent dedicated meeting.MethodsThe authors have evaluated all the available evidence reported in the literature and have compared experience among various departments in leading European centers in order to provide a standardization of the DISE procedure and an in-depth insight in the main aspects of this technique.ResultsA proposal of the DISE procedure standardization has been achieved with a general agreement concerning the terminology, indications, contraindications, required preliminary examinations, setting, technical equipment required, staffing, local anesthesia and nasal decongestion, patient positioning, basis and special diagnostic maneuvers, and the applied sedation drugs and observation windows. Otherwise, no consensus has been reached on a scoring and classification system.ConclusionsAlthough consensus has been reached on several aspects of the DISE procedure, some topics remain open to future research, such as a better analysis of the importance of positional aspects during DISE and a further comparison of the differences in degree, level and pattern of upper airway collapse observed during DISE versus during natural sleep and awake endoscopy. Finally, a universally accepted scoring and classification system is lacking.

Three-Year Outcomes of Cranial Nerve Stimulation for Obstructive Sleep Apnea The STAR Trial

Objective To describe the 36-month clinical and polysomnography (PSG) outcomes in an obstructive sleep apnea (OSA) cohort treated with hypoglossal cranial nerve upper airway stimulation (UAS). Study Design A multicenter prospective cohort study. Setting Industry-supported multicenter academic and clinical setting. Subjects Participants (n = 116) at 36 months from a cohort of 126 implanted participants. Methods Participants were enrolled in a prospective phase III trial evaluating the efficacy of UAS for moderated to severe OSA. Prospective outcomes included apnea-hypopnea index, oxygen desaturation index, other PSG measures, self-reported measures of sleepiness, sleep-related quality of life, and snoring. Results Of 126 enrolled participants, 116 (92%) completed 36-month follow-up evaluation per protocol; 98 participants additionally agreed to a voluntary 36-month PSG. Self-report daily device usage was 81%. In the PSG group, 74% met the a priori definition of success with the primary outcomes of apnea-hypopnea index, reduced from the median value of 28.2 events per hour at baseline to 8.7 and 6.2 at 12 and 36 months, respectively. Similarly, self-reported outcomes improved from baseline to 12 months and were maintained at 36 months. Soft or no snoring reported by bed partner increased from 17% at baseline to 80% at 36 months. Serious device-related adverse events were rare, with 1 elective device explantation from 12 to 36 months. Conclusion Long-term 3-year improvements in objective respiratory and subjective quality-of-life outcome measures are maintained. Adverse events are uncommon. UAS is a successful and appropriate long-term treatment for individuals with moderate to severe OSA.

Tongue-base suspension with a soft tissue-to-bone anchor for obstructive sleep apnea: preliminary clinical results of a new minimally invasive technique.

The Repose system is a new minimally invasive technique for tongue-base suspension in the treatment of sleep-disordered breathing caused by tongue-base collapse. It involves the insertion of a titanium miniscrew with attached suture into the anterior intraoral mandible and passing the suture through the tongue base. The procedure was performed in 16 patients with sleep-disordered breathing. Fourteen patients reported an improvement in daytime sleepiness, and their bed partners reported an improvement in snoring. The mean respiratory distress index before surgery was 35. Two months after surgery, the mean respiratory distress index was 17, an improvement of 51.4% (P = 0.001, 2-tailed t test). These preliminary results show the initial efficacy and safety of this new surgical procedure. (Otolaryngol Head Neck Surg 2000;122:100–3.)

Tongue base reduction with temperature-controlled radiofrequency volumetric tissue reduction for treatment of obstructive sleep apnea syndrome.

In recent years a considerable effort has been made to establish the use of different surgical techniques for the treatment of obstructive sleep apnea syndrome (OSAS). Nevertheless, treatment of hypopharyngeal obstruction due to tongue base hypertrophy remains in many ways an unsolved problem. The aim of this study was to evaluate the safety and efficacy of tongue base reduction with temperature-controlled radiofrequency volumetric tissue reduction in the treatment of OSAS. Twenty patients with OSAS and tongue base hypertrophy were treated with radiofrequency tissue ablation. An intensified treatment protocol was used, delivering 2,800 J per treatment session under local anesthesia. Two nights of polysomnography testing were performed before and after treatment. Daytime sleepiness, snoring and postoperative morbidity were assessed using questionnaires. Mean respiratory disturbance index (RDI) was reduced from 32.1 to 24.9/h after a mean of 3.4 treatment sessions. Six patients (33%) were cured after the procedure (reduction in RDI of S 50% and a postoperative RDI of <15/h) and ten (55%) showed an improvement of >20% in their RDI. Daytime sleepiness and snoring improved significantly. Peri- and postoperative morbidity was low; one severe complication occurred (tongue base abscess). We were able to achieve similar cure and responder rates to those reported in a recently published pilot study but with a reduced number of treatment sessions. We believe that this technique may improve patient acceptance and have beneficial cost implications.

Evaluation of Drug-Induced Sleep Endoscopy as a Patient Selection Tool for Implanted Upper Airway Stimulation for Obstructive Sleep Apnea

STUDY OBJECTIVES To study the possible predictive value of drug-induced sleep endoscopy (DISE) in assessing therapeutic response to implanted upper airway stimulation (UAS) for obstructive sleep apnea (OSA). METHODS During DISE, artificial sleep is induced by midazolam and/or propofol, and the pharyngeal collapse patterns are visualized using a flexible fiberoptic nasopharyngoscope. The level (palate, oropharynx, tongue base, hypopharynx/epiglottis), the direction (anteroposterior, concentric, lateral), and the degree of collapse (none, partial, or complete) were scored in a standard fashion. RESULTS We report on the correlation between DISE results and therapy response in 21 OSA patients (apnea-hypopnea index [AHI] 38.5 ± 11.8/h; body mass index [BMI] 28 ± 2 kg/m(2), age 55 ± 11 y, 20 male/1 female) who underwent DISE before implantation of a UAS system. Statistical analysis revealed a significantly better outcome with UAS in patients (n = 16) without palatal complete concentric collapse (CCC), reducing AHI from 37.6 ± 11.4/h at baseline to 11.1 ± 12.0/h with UAS (p < 0.001). No statistical difference was noted in AHI or BMI at baseline between the patients with and without palatal CCC. In addition, no predictive value was found for the other DISE collapse patterns documented. CONCLUSIONS The absence of palatal CCC during DISE may predict therapeutic success with implanted UAS therapy. DISE can be recommended as a patient selection tool for implanted UAS to treat OSA.

Multilevel Surgery for Obstructive Sleep Apnea: Short-Term Results

OBJECTIVE: To determine the efficacy of a new multilevel surgical protocol for obstructive sleep apnea (OSA). STUDY DESIGN AND SETTING: Sixty patients with moderate to severe OSA because of multilevel pharyngeal obstruction were enrolled into this prospective, controlled clinical trial after clinical examination, endoscopy, and polysomnography. Surgery included uvulaflap, tonsillectomy, hyoid suspension, and radiofrequency treatment of the tongue base (group A). A second group did not receive hyoid suspension (group B). In both groups, nasal surgery was performed if necessary. Polysomnography and Epworth Sleepines Scale (ESS) were recorded at baseline and 2 to 15 months after surgery. RESULTS: In group A, the mean apnea-hypopnea index (AHI) decreased significantly after surgery (38.9 ± 20.0 vs 20.7 ± 20.6, P < 0.0001), whereas in group B the AHI did not. All secondary variables (minimal oxygen saturation, mean oxygen saturation, arousal index), and the ESS significantly improved in group A with only changes in arousal index and ESS reaching levels of significance in group B. CONCLUSION: The presented protocol including the hyoid suspension proved to be effective in the treatment of OSA, whereas surgery without hyoid suspension was less successful.

Long-Term Results of Palatal Implants for Primary Snoring

OBJECTIVE: To determine the safety and efficacy of the Pillar Palatal Implant System over a 1-year follow-up period. STUDY DESIGN AND SETTING: In this prospective study, 40 healthy adult patients with primary snoring due to palatal flutter were treated after clinical, polysomnographic, and endoscopic examination. Under local anesthesia 3 implants were placed into the soft palate. Postoperative morbidity and functional parameters were assessed. Snoring and daytime sleepiness were assessed before and 90, 180, and 360 days after surgery. Objective data were obtained by polysomnography and SNAP-recording before and 90 days after treatment. RESULTS: All implants were placed without complications. A total of 13 implants partially extruded uneventfully in 10 patients. Functional parameters remained unchanged. After 1 year, snoring was reduced from 7.1 ± 1.9 to 4.8 ± 2.5 (Visual-Analogue-Scale, P < 0.05) and daytime sleepiness from 6.1 ± 3.2 to 4.9 ± 3.1 (Epworth-Sleepiness-Scale, P < 0.05). SNAP data and polysomnography parameters showed clinically irrelevant changes. CONCLUSION: Our data demonstrate a significant decrease in snoring and daytime sleepiness over a period of one year.

Randomized Controlled Withdrawal Study of Upper Airway Stimulation on OSA: Short- and Long-term Effect

Objective To assess the efficacy and durability of upper airway stimulation via the hypoglossal nerve on obstructive sleep apnea (OSA) severity including objective and subjective clinical outcome measures. Study Design A randomized controlled therapy withdrawal study. Setting Industry-supported multicenter academic and clinical setting. Subjects A consecutive cohort of 46 responders at 12 months from a prospective phase III trial of 126 implanted participants. Methods Participants were randomized to either therapy maintenance (“ON”) group or therapy withdrawal (“OFF”) group for a minimum of 1 week. Short-term withdrawal effect as well as durability at 18 months of primary (apnea hypopnea index and oxygen desaturation index) and secondary outcomes (arousal index, oxygen desaturation metrics, Epworth Sleepiness Scale, Functional Outcomes of Sleep Questionnaire, snoring, and blood pressure) were assessed. Results Both therapy withdrawal group and maintenance group demonstrated significant improvements in outcomes at 12 months compared to study baseline. In the randomized assessment, therapy withdrawal group returned to baseline, and therapy maintenance group demonstrated no change. At 18 months with therapy on in both groups, all objective respiratory and subjective outcome measures showed sustained improvement similar to those observed at 12 months. Conclusion Withdrawal of therapeutic upper airway stimulation results in worsening of both objective and subjective measures of sleep and breathing, which when resumed results in sustained effect at 18 months. Reduction of obstructive sleep apnea severity and improvement of quality of life were attributed directly to the effects of the electrical stimulation of the hypoglossal nerve.