Obstructive Sleep Apnea, Sleep Disordered Breathing
Conditions
Keywords
Sleep Apnea
Brief summary
In this study the investigators will determine whether using high flow oxygen in moderate-to-severe Obstructive Sleep Apnea patients following a major non cardiac surgery is more efficacious than usual care in preventing decrease in oxygen level in blood.
Detailed description
The POSA-II trial is a culmination of the investigator's program of research to prevent postoperative adverse outcomes in surgical patients with untreated Obstructive Sleep Apnea (OSA). It is a multi center open label, randomized clinical trial of nasal high-flow vs. usual care in patients with untreated moderate-to-severe OSA undergoing major non cardiac surgery. It is a proof of concept trial to show that nasal high-flow reduces severe desaturation, the causal mechanism for OSA-related adverse events, and to collect key feasibility data for a large international multi center trial with enough power to detect effects on the clinical outcomes. Eligible patients undergoing major non cardiac surgery with high-risk OSA will have a home sleep study. One hundred and ninety patients with moderate-to-severe Sleep Apnea will be randomized into either nasal high-flow or usual care group. Sleep studies, oximetry, electrocardiogram (ECG), and Troponin will be done preoperatively. Postoperatively, ECG and Troponin will be determined daily for the 1st three days, and nocturnal oximetry for the 1st 3 nights. Patients will be followed during their hospitalization and for 30 days postoperatively to ascertain any adverse outcomes. A blinded clinical events committee will adjudicate all components of the composite outcome.
Interventions
OTHERNasal High Flow
Delivery of oxygen via OptiflowTM system (AirvoTM, Fisher & Paykel Inc.) with airflow of 20 to 50 Litre/minute
OTHERUsual Care
Delivery of oxygen at 2-4 Litre/minute via nasal cannula or 6 Litre/minute via face mask
Sponsors
University Health Network, Toronto
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
45 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Adult, age ≥45 years, undergoing major elective non cardiac surgery under general and/or regional anesthesia with anticipated overnight stay or longer in hospital * Patients with untreated moderate-to-severe Obstructive Sleep Apnea. * STOP-Bang score 5 or higher
Exclusion criteria
* Predetermined need for postoperative CPAP therapy or ventilation, * Cheyne-Stokes respiration or Central Apnea, * Oxygen dependent due to moderate to severe chronic obstructive lung disease available Forced Expiratory Volume at 1 second of \< 50% predicted) or advanced interstitial lung disease, * Pre-existing chronic hypercapnia or obesity hypoventilation syndrome, Intracranial and otolaryngological procedures, and * Unable to use nasal high-flow (nasal/oral malformations, pre-existing tracheostomy, planned postoperative nasal packing).
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Oxygen Desaturation Index (ODI) | 72 hours | The investigators will measure Oxygen Desaturation Index(the number of desaturation events per hour) by using Pulsox 300i for maximum of three nights post-operatively at the hospital preventing the severe desaturation in surgical patients with untreated moderate-to-severe OSA undergoing major non cardiac surgery. Higher values of ODI are considered worst. If successful, it will provide feasibility data for the performance of a large randomized clinical trial focusing on clinical outcomes and the cost effectiveness of the therapy to the health care system. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Time (minutes) spent below 90% and 80% SpO2 (T90, T80) | 72 hours | The investigators will measure the time spent in minutes with SpO2 between 0% to %79 (T80) and the time spent in minutes with SpO2 between 0% to 89% (T90). ODI, T90 and T80 will serve as surrogate outcomes of adverse events in the pilot study. In POSA study, an increase in time spent with SpO2 \<80% after surgery was associated with a higher risk of postoperative vascular events under usual care. |
| Compliance to Nasal High-Flow | 72 hours | To determine the tolerability and adherence of patients with OSA to Nasal High-Flow in the wards using a 10-point numeric rating scale to grade general discomfort, in which points 0 to 3 means not comfortable, 4 to 6 means comfortable and 7 to 10 means the most comfortable. |
| Titration protocol of nasal high-flow | 72 hours | The appropriate titration protocol of nasal high-flow will be measured; FiO2: flow rates. |
| The rate of postoperative adverse events | 30 days | The rate of postoperative cardiovascular events will be collected during hospitalization and following discharge from hospital, emergency department (if visited) and physician records, and patient by phone at day 30. Adjudicators who are blinded to the results of the ECG, Troponin, sleep study and oximetry will evaluate outcome events. |
Countries
Canada, Hong Kong, Malaysia, Singapore
Outcome results
None listed