Physiology of When to Stimulate

In this episode of Talking Sleep, host Dr. Seema Khosla welcomes Dr. David Kent, Associate Professor and Director of Sleep Surgery in the Department of Otolaryngology-Head and Neck Surgery at Vanderbilt University Medical Center, to discuss the evolving landscape of hypoglossal nerve stimulation for obstructive sleep apnea treatment.

With the recent FDA clearance of a new hypoglossal nerve stimulator, patients now have three device options available or coming soon. Dr. Kent, whose research explores upper airway neurophysiology and novel OSA treatments, helps clinicians understand the fundamental differences between these devices and how to select the most appropriate option for individual patients. He discloses his past consulting relationship with Inspire and current consulting role with Nyxoah to provide transparent context for the discussion.

The conversation begins with the foundational premise of hypoglossal nerve stimulation and why it effectively treats obstructive sleep apnea. Dr. Kent traces Inspire's evolution since its 2013 FDA approval, explaining the current implantation process and how the technology has advanced over the past decade.

A significant focus is placed on Genio, with Dr. Kent explaining how its design resembles a cochlear implant—breaking down this comparison for pulmonologists and other non-surgical specialists. Critical distinctions emerge: Genio uses bilateral stimulation versus Inspire's unilateral approach, lacks a respiratory sensor, and employs an external rechargeable battery. Dr. Kent clarifies the practical implications of these differences, including how pulse delivery is timed without respiratory synchronization, what external battery charging means for daily use, smartphone Bluetooth connectivity, and MRI compatibility considerations.

The episode tackles important clinical questions: Is bilateral hypoglossal nerve stimulation superior to unilateral stimulation? Does complete concentric collapse (CCC) matter as a contraindication, and if conflicting data exists about CCC exclusion criteria, how should this inform patient selection? Is drug-induced sleep endoscopy (DISE) necessary for all candidates? Dr. Kent discusses how the STAR trial differed from the DREAM trial and how pandemic timing affected patient outcomes and data interpretation.

Looking toward the future, Dr. Kent provides insights into Aura6000, expected to be available in 2027, and discusses his research on ansa cervicalis stimulation as a potential complementary approach, acknowledging that hypoglossal nerve stimulation alone may not be the complete solution for all patients.

A particularly valuable discussion addresses setting realistic patient expectations. Dr. Kent shares his experience with patients who arrive with preconceived notions about Inspire based on marketing or word-of-mouth, requiring significant time to align expectations with reality. He walks through his clinical conversations comparing Inspire versus Genio, helping clinicians develop frameworks for these nuanced discussions.

Whether you're counseling patients about device-based OSA treatment options, trying to distinguish between available technologies, or preparing for the expanding landscape of hypoglossal nerve stimulation, this episode provides essential comparative insights.

Join us for this comprehensive discussion about the past, present, and future of implantable OSA therapy.