IMAGES: Drug-Induced Sleep Endoscopy: An Investigative Tool for Mechanisms of PAP Failure

Mechanistic insights from sleep endoscopy related to oronasal mask failures: a case report

A 71-year-old male with severe obstructive sleep apnea and nasal septal deviation presented to a positive airway pressure (PAP) alternatives clinic due to persistent obstructive events on both continuous PAP and bilevel PAP therapy delivered via oronasal mask. He underwent drug-induced sleep endoscopy with PAP titration to determine the mechanism of oronasal mask failure. A nasal mask was also applied and titrated for comparison. Drug-induced sleep endoscopy with PAP showed tongue base collapse which resolved at low pressure using a nasal mask. Application of an oronasal mask increased minimum therapeutic PAP level. Tightening the mask worsened tongue base collapse, which was not resolved by increasing the PAP level. Following nasal surgery, the patient was able to tolerate nasal continuous PAP at low therapeutic pressure, which resulted in both objective and self-reported improvement is his obstructive sleep apnea. This case highlights the ability of drug-induced sleep endoscopy with PAP to determine the mechanistic cause of oronasal mask failure.

CITATION

Harkins TR, Seay E, Schwartz AR, Thuler E, Dedhia RC. Mechanistic insights from sleep endoscopy related to oronasal mask failures: a case report. J Clin Sleep Med. 2024;20(9):1551-1554.

Evaluation of Therapeutic Positive Airway Pressure as a Hypoglossal Nerve Stimulation Predictor in Patients With Obstructive Sleep Apnea

Importance

Recent retrospective hypoglossal nerve stimulation (HGNS) outcomes data suggest that patients with low therapeutic positive airway pressure (PAP) levels achieve greater success than patients with high therapeutic PAP levels.

Objective

To examine the use of therapeutic nasal PAP levels at the soft palate in predicting the outcomes of HGNS for patients with obstructive sleep apnea.

Design, Setting, and Participants

This prospective cohort study used drug-induced sleep endoscopy (DISE) to evaluate the predictive capacity of therapeutic PAP levels in HGNS outcomes. In an academic sleep surgery center, 27 consecutive patients with obstructive sleep apnea who underwent DISE before implantation of an HGNS device were evaluated. The study was conducted from May 1, 2018, to June 26, 2019.

Exposures

Positive airway pressure delivered through a nasal mask during DISE.

Main Outcomes and Measures

Improvement in apnea-hypopnea index as measured from full-night preoperative and postoperative efficacy studies.

Results

Twenty-seven patients met all inclusion criteria. The mean (SD) age was 62.0 (14.4) years, 14 participants were men (51.9%), and mean body mass index was 28.1 (4.0). Responders to HGNS therapy (n = 18) had significantly lower mean (SD) palatal opening pressure compared with nonresponders (n = 9) (5.0 [2.8] vs 9.2 [3.7] cm H2O, respectively; mean difference, -4.2; 95% CI, -6.8 to -1.6 cm H2O). After adjusting for age, sex, and body mass index, the mean palatal opening pressure value for the responders remained 3.5 cm H2O lower (95% CI, -6.7 to -0.4 cm H2O) than that of nonresponders. A palatal opening pressure cutoff level less than 8 cm H2O demonstrated a positive predictive value of 82.4%; sensitivity, 77.8%; and specificity, 66.7%.

Conclusions and Relevance

In this small prospective cohort study, therapeutic nasal PAP levels during DISE differed significantly between responder and nonresponders to HGNS. Because DISE represents a mandatory, relatively standardized diagnostic tool for HGNS candidacy, the use of therapeutic nasal PAP through DISE can be broadly implemented and studied across multiple centers to possibly improve patient selection for HGNS.

The Emerging Role of Drug-Induced Sleep Endoscopy in the Management of Obstructive Sleep Apnea

Obstructive sleep apnea is a prevalent sleep disorder characterized by partial or complete obstruction of the upper airway. Continuous positive airway pressure is the first-line therapy for most patients, but adherence is often poor. Alternative treatment options such as mandibular advancement devices, positional therapy, and surgical interventions including upper airway stimulation target different levels and patterns of obstruction with varying degrees of success. Drug-induced sleep endoscopy enables the visualization of upper airway obstruction under conditions mimicking sleep. In the era of precision medicine, this additional information may facilitate better decision-making when prescribing alternative treatment modalities, with the hope of achieving better adherence and/or success rates. This review discusses the current knowledge and evidence on the role of drug-induced sleep endoscopy in the non-positive airway pressure management of obstructive sleep apnea.

Drug-Induced Sleep Endoscopy: Evaluation of a Selection Tool for Treatment Modalities for Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) is a very common disorder with important day and nighttime symptoms and long-term effects on health. Different treatment modalities such as positive airway pressure (PAP), oral appliance therapy using custom-made, titratable mandibular advancement devices (MAD), different types of surgery and positional therapy have been introduced over the years, with patient preference and adherence to therapy being key elements in improving treatment outcomes. Several patient selection tools to improve treatment outcomes have been introduced and evaluated over the years. Drug-induced sleep endoscopy (DISE) is a procedure that provides real-time upper airway evaluation of the sites of flutter and upper airway collapse. This review focuses on the indications and contraindications for DISE, methods of sedation and evaluation, add-on maneuvers, and the results on patient selection and treatment outcomes. A PICO approach was used to clarify the aims of this review. DISE has the advantage of being easily accessible in most ENT practices and being 3-dimensional, dynamic, site specific, safe and it is valuable in selecting patients for upper airway surgery and oral appliance therapy. There is a strong interest for further standardization and exploration of the predictive value of this evolving technique.