This study intends to test the feasibility of measurement of the critical closing pressure (Pcrit) during drug-induced sleep endoscopy (DISE) for use in future studies, which are aimed at finding an alternative method for patient selection and response prediction before implementation of non-CPAP therapies.Twenty patients diagnosed with OSA and eligible for non-CPAP treatments are going to be included into this study and undergo these measurements. Drug-induced sleep endoscopy (DISE) is part of the standard clinical care for OSA patients that are eligible for non-CPAP therapies. We aim to expand this procedure with measurement of Pcrit, oesophageal pressure, airflow, EEG, EOG, respiratory effort, SpO2 and chin EMG during this study.
Patients from the ENT department will be recruited and informed about the study. After obtaining informed consent, the patients will undergo DISE according to the normal clinical care.The study will be performed during this clinical DISE, using a standard polysomnographic set-up (Alice 6 LDx, Philips Respironics) expanded with pressure and flow measurements. After measurements and evaluations are done, the most suitable treatment option based on the DISE and PSG findings, as defined in the standard clinical care, will be advised to the patient. The treatment and its further choice are not part of the current study protocol.
Study Type
OBSERVATIONAL
Enrollment
13
DISE is performed in a semi-dark, silent operating theatre, starting with the patient in supine position. To first induce sleep, an IV bolus of midazolam (1.5 mg) is administered. Then, a flexible fiberoptic nasopharyngoscope (Olympus END-GP, 3.7 mm diameter, Olympus Europe GmbH, Hamburg, Germany) is inserted through one of the nostrils. Either at the start of the examination or while holding the scope at the level of the palate, propofol (2.0-3.0 µg/ml) will be administered via a target-controlled infusion (TCI) pump. Sleep occurrence is confirmed using the additional EEG measurement.
After sleep onset, the CPAP pressure well be increased until no flow limitations are observed. This pressure is called the holding pressure and is used as a base for all the following measurements for that individual OSA patient. After observing sleep stage 2 or 3, the holding pressure is reduced abruptly by 1 cmH2O during expiration for 5 breaths. Then the pressure is set back to the holding pressure for the duration of 1 minute. This procedure is repeated until obstructive sleep apnea is noted.
Antwerp University Hospital
Edegem, Antwerp, Belgium
Critical closing pressure of the upper airway (Pcrit)
The pressure at which the upper airway collpases measured in cm H2O.
Time frame: 1 hour
Airflow
By using a pneumotachometer attached to a transducer the inspiratory and expiratory airflow (l/s) will be measured.
Time frame: 1 hour
EEG
Using electroencephalogram electrodes C3, C4, O1, F4 to evaluate sleep and wake stages and ground and system reference electrodes (volt)
Time frame: 1 hour
Esophageal pressure
The pressure of the esophagus measured in cmH2O using an esophageal ballooon catheter.
Time frame: 1 hour
SpO2
using a pulse oximetry device, to non-invasively measure arterial oxygen saturation level (%).
Time frame: 1 hour
EMG
Using electromyogram electrodes to evaluate muscular activity (volt)
Time frame: 1 hour
EOG
electrooculogram electrodes to evaluate rapid eye movements (volt)
Time frame: 1 hour
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.