Mechanisms of Pharyngeal Collapse in Sleep Apnea, Study A

NCT ID: NCT01728974

Last Updated: 2019-07-11

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 26 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2012-12-08
• Study Completion Date: 2018-12-26

Brief Summary

In obstructive sleep apnea, the upper airway recurrently closes during sleep. The mechanisms that lead to airway closure are not completely understood. While the airway of some people narrows and airflow decreases during inspiration due to increasing inspiratory effort, others maintain constant airflow throughout inspiration. Airway neuromuscular reflexes may protect against airway narrowing that occurs due to increasing inspiratory effort. To test this hypothesis, the investigators will initially measure airway neuromuscular reflex and inspiratory flow and then attenuate neuromuscular reflex through topical pharyngeal anesthesia to observe the effects on inspiratory flow.

Detailed Description

The mechanisms that lead to airway closure are not completely understood. While the airway of some people narrows and airflow decreases during inspiration due to increasing inspiratory effort, others maintain constant airflow throughout inspiration (negative effort dependence, NED). The investigators hypothesize that upper airway neuromuscular reflexes may protect against narrowing that occurs due to increasing inspiratory effort. Topical oropharyngeal anesthesia has been shown to reduce neuromuscular reflexes. Thus, the investigators also hypothesize that patients with stable inspiratory flow will develop NED once the reflexes have been impaired with topical anesthetic. The investigators plan to:

1. measure upper airway muscle EMG to assess how it corresponds to the presence or absence of NED. This aim will allow us to test the hypothesis that robust upper airway muscle reflexes can protect against NED.

2. reduce upper airway muscle activity and reflexes by topical oropharyngeal anesthesia. This will allow us to test the hypothesis that attenuated upper airway muscle activity induced by topical anesthesia can induce NED.

Conditions

Obstructive Sleep Apnea; Pathophysiology

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: OTHER
• Blinding Strategy: NONE

Study Groups

Pharyngeal topical anesthesia

Pharyngeal topical anesthesia will be performed using 4% lidocaine spray

Group Type: EXPERIMENTAL

Pharyngeal topical anesthesia

Intervention Type: OTHER

Pharyngeal topical anesthesia will be performed using 4% lidocaine spray

Interventions

Pharyngeal topical anesthesia

Pharyngeal topical anesthesia will be performed using 4% lidocaine spray

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Normal subjects or patients with OSA

Exclusion Criteria

• Any unstable cardiac condition (other than well controlled hypertension) or pulmonary problems.
• Any medication known to influence breathing, sleep/arousal or muscle physiology
• Concurrent sleep disorders (insomnia, narcolepsy, central sleep apnea or parasomnia)
• Claustrophobia
• Inability to sleep supine
• Allergy to lidocaine or oxymetazoline HCl
• For women: Pregnancy

• Minimum Eligible Age: 21 Years
• Maximum Eligible Age: 65 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

National Heart, Lung, and Blood Institute (NHLBI)

NIH

Sponsor Role: collaborator

Brigham and Women's Hospital

OTHER

Sponsor Role: lead

Responsible Party

David Andrew Wellman

Andrew Wellman

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

David A Wellman

Role: PRINCIPAL_INVESTIGATOR

Brigham and Women's Hospital

Locations

Brigham and Women's Hospital

Boston, Massachusetts, United States

Countries

United States

Other Identifiers

1R01HL102321-01A1

Identifier Type: NIH

Identifier Source: secondary_id

View Link

2012P000957A

Identifier Type: -

Identifier Source: org_study_id