The purpose of this study is to assess the effect of continuous positive airway pressure (CPAP) on functional outcome in patients with acute stroke, the investigators conducted a sham-controlled, double-blind pilot trial during inpatient rehabilitation.
Patients with acute stroke were recruited and randomly assigned to auto-titrating or sham-CPAP during their rehabilitation stay.
All acute stroke patients admitted to the inpatient rehabilitation service at the University of Washington were invited to participate in the study. Given the high prevalence of obstructive sleep apnea (OSA) in this population, no screen for OSA was performed. Enrolled patients were assigned randomly to active-CPAP with auto-titrating pressures or to sham-CPAP with an otherwise identical device but with pressures ≤ 1 cm water. Subjects used active or sham-CPAP for the duration of inpatient rehabilitation, but no longer than 28 days. CPAP compliance was assessed by memory card that recorded mask-on time. Other information on download, such as apnea-hypopnea index, was only available on active-CPAP and not assessed by investigators in real time. In this study, the investigators defined tolerance as any continued use of CPAP at night and adherence as mean hours of CPAP use per night in those who were CPAP tolerant.
- Auto-titrating CPAP Device
Intervention Desc: Auto-titrating CPAP was initiated after admission to the inpatient rehabilitation unit for the duration of rehabilitation but not exceeding 28 days. A respiratory therapist visited patients nightly to document adherence and address issues arising at night. A sleep technologist also met with patients at least twice weekly to monitor safety and adverse events and make any adjustments to the CPAP mask or machine. Efforts to improve adherence to CPAP for patients treated with active-CPAP included patient education, desensitization of CPAP through brief periods of daytime use, adjustments of humidity and mask (including addition of a chin strap), decreasing CPAP maximum pressure and use of expiratory pressure relief (CFlex) for patients treated with active-CPAP. ARM 1: Kind: Experimental Label: Active-CPAP Description: Patients assigned to active-CPAP were treated with auto-titrating CPAP, where an auto-titrator adjusted the delivered pressure between 4 to 20 cm of water to eliminate obstructive events for a goal apnea-hypopnea index less than or equal to 5.
- Sham-CPAP Device
Intervention Desc: Sham-CPAP was initiated after admission to the inpatient rehabilitation unit for the duration of rehabilitation but not exceeding 28 days. A respiratory therapist visited patients nightly to document adherence and address issues arising at night. A sleep technologist also met with patients at least twice weekly to monitor safety and adverse events and make any adjustments to the CPAP mask or machine. Efforts to improve adherence to CPAP for patients treated with sham-CPAP included patient education, desensitization of CPAP through brief periods of daytime use and adjustments of humidity and mask, including addition of a chin strap. ARM 1: Kind: Experimental Label: Sham-CPAP Description: The sham-CPAP device in our study was designed to entail no risks beyond those with standard CPAP and provide a high level of blinding. The sham-CPAP device is an auto-titrating CPAP with an internal flow restrictor and a modified elbow attached to the nasal mask. The elbow modification creates a larger than standard air leak that serves to prevent any chances of carbon dioxide rebreathing and delivers a pressure at the mask in¬terface of roughly 0.75 to 1 cm water. The elbow modification is not noticeable when the device is fully assembled to avoid the possibility of unblinding patients, providers, or study personnel. The elbow modification could only be used on standard nasal masks; consequently full facemasks and nasal pillows were excluded for patients in both active and sham-CPAP.
- Allocation: Randomized
- Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
- Purpose: Treatment
- Endpoint: Safety/Efficacy Study
- Intervention: Parallel Assignment
|Type||Measure||Time Frame||Safety Issue|
|Primary||Feasibility of enrolling eligible stroke patients admitted to inpatient rehabilitation for an acute ischemic or hemorrhagic stroke into a pilot, randomized clinical trial of active versus sham CPAP.||18 months||No|
|Secondary||Improve adherence to CPAP in all patients enrolled in this clinical trial.||18 months||No|
|Secondary||The effect of auto-titrating CPAP on neurological recovery compared to sham-CPAP.||18 months||No|