Use of High-resolution Manometry to Detect Upper Airway Obstruction During Sleep
Obstructive sleep apnea (OSA) is a major public health issue in both children and adults,
present in 1-5% of children and 10-30% of adults. It is characterized by repeated episodes of
airway obstruction during sleep, leading to brain arousal, sympathetic activation, oxygen
desaturation, sleep fragmentation, and non-restorative sleep. Patients report daytime
tiredness, insomnia, and morning headaches. Children with OSA experience daytime somnolence,
difficulties at school, behavioral problems, enuresis, and reduced quality of life. If left
untreated, OSA can lead to numerous complications including hypertension, cardiovascular
disease, stroke, and insulin resistance. Sleep partners are also affected, with patients
viewing their disorder as a burden and sleeping in separate rooms. Further, disease
prevalence is increasing as obesity increases.
Continuous positive airway pressure (CPAP) is the current gold standard treatment for OSA. If
used effectively and consistently, it can improve patient symptoms. However, adherence is
generally poor, with patients experiencing physical discomfort, chest discomfort, and dry
mouth. For those patients that cannot tolerate CPAP, surgical intervention is an option. In
children, this typically starts with adenotonsillectomy. However, 20-75% of children will
have persistent symptoms after adenotonsillectomy. In adults, anatomic factors including
tonsil hypertrophy and redundant pharyngeal tissue can contribute to upper airway obstruction
and may also necessitate higher pressures for effective CPAP treatment. Even if surgical
intervention does not cure the OSA, it may make CPAP more tolerable and improve CPAP
adherence.
Sleep-related airway obstruction is a complex phenomenon potentially involving multiple
anatomic levels. For patients with persistent symptoms despite initial therapy or intolerance
to CPAP, further evaluation of the upper airway is clinically valuable. Polysomnography (PSG)
is the gold standard for diagnosing OSA, but it does not provide information on the
location(s) of upper airway obstruction. Knowledge of the precise sites of obstruction is
critical to planning effective sleep surgery. Currently, this is accomplished with
drug-induced sleep endoscopy (DISE). DISE was originally proposed in 1991 and involves
administering anesthetic to a patient to simulate a sleep state, and then visualizing the
upper airway using transnasal flexible endoscopy. Sites of obstruction at key locations
including the adenoids, soft palate, lateral oropharynx, tongue base, and epiglottis can be
identified.
Though DISE offers valuable clinical information, it has notable limitations. First, it
cannot evaluate the entire upper airway simultaneously, as any obstruction occurring
superiorly precludes visualization of any obstruction occurring more inferiorly. Second,
interpretation of DISE is subjective and there is no universally accepted system for
analysis. Rating systems are qualitative, using grades such as complete, partial, or no
obstruction as opposed to quantitative measurements.
The optimal sleep assessment would be quantitative, reliable, and provide information on the
entire upper airway simultaneously. A potential alternative to DISE which could meet these
criteria is sleep manometry. Measurement of upper airway pressures captures the effects of
obstruction along the entire upper airway, from the nasopharynx to larynx. Prior studies have
attempted to employ manometry, but have been limited primarily by inadequate equipment and
suboptimal methods of data analysis. Woodson et al. used a solid-state manometer with
diameter of 2.3 mm and 5 sensors to detect palatal obstruction and tongue base obstruction in
patients with OSA. They also used the same approach to detect persistent tongue base
obstruction following uvulopalatopharyngoplasty. While these studies help demonstrate that
manometry can be a useful adjunct to OSA assessment, they are severely limited both by the
type of manometer used as well as the lack of a clear, detailed description of the method of
data analysis.
High-resolution manometry (HRM) uses pressure censors spaced 1 cm apart to allow for pressure
measurement along the entire upper airway. The investigators have previously applied HRM to
assessment of swallow physiology. Sophisticated methods of automated data analysis have been
developed that have been shown to be reliable for both expert and novice users . Further,
pattern recognition techniques have been applied to identify dysphagia and specific
swallowing abnormalities. Application of this technology and modification of existing data
analysis platforms will allow for a quantitative, reliable, and comprehensive assessment of
upper airway obstruction during sleep in both children and adults, with potential for
development of algorithms to predict effects of targeted surgical therapy at all levels of
the upper airway.
Timothy Mcculloch
All
5 Years to 90 Years old
NA
NCT04139499
Acute obstructive laryngitis [croup] and epiglottitis, Obstructive Sleep Apnea
Stroke Prevention in the Wisconsin Native American Population
This project will develop a "Stroke Awareness Team" including training of Oneida Health
Service Coaches working in partnership with the UW team for a population-based health
awareness program. This team will develop a series of Oneida Nation Healthy Living and Stroke
Awareness Events (from now on health events) to provide education as to the severity of the
problem as well as our standard therapies for lifestyle change and risk factor avoidance.
This will include education of the healthy members of the tribe including the children to
identify signs of stroke and TIA in their elders as well as to develop healthy lifestyles at
the earliest of ages to influence the elders to modify their risks.
Robert Dempsey, MD
All
55 Years to 80 Years old
N/A
NCT04382963
Cerebral infarction, Brain & Neurological, Prevention & Screening, Stroke, Atherosclerosis
Breathe 2 Project 3: Comprehensive Chronic Care
This study will evaluate Comprehensive Chronic Care (CCC), a healthcare treatment approach
designed to increase smoking treatment engagement and abstinence among primary care patients
who smoke. This research will compare CCC with Standard of Care (SC) on the following
outcomes: abstinence at 18 months (primary outcome), treatment reach, and cost-effectiveness.
Participation in the study will last 18 months.
Michael Fiore
All
18 Years and over
N/A
NCT05382221
Smoking Cessation, Smoking Abstinence, Nicotine dependence, Other