Evaluation of the add-on NOWAPI® medical device for remote monitoring of compliance to Continuous Positive Airway Pressure and treatment efficacy in obstructive sleep apnea.

BACKGROUND: Optimizing the measurement of Continuous Positive Airway Pressure (CPAP) compliance and treatment efficacy is paramount for patients with obstructive sleep apnea syndrome (OSAS). Compliance knowledge is currently based on data coming from CPAP machines; however algorithms and measured parameters vary from one machine to another. This study was conducted to clinically evaluate a novel device, NOWAPI(®), designed to assess compliance remotely in conjunction with any CPAP machine. NOWAPI(®) was tested against polygraphy, the gold standard for the measurement of CPAP treatment duration and residual apnea-hypopnea index (AHI). METHODS: Single group assignment, open label, non-randomized. Sleep laboratory setting. 22 adult patients with OSAS treated by CPAP were included. Recordings were performed during one night while the patient was treated with his/her usual CPAP and interface. NOWAPI(®) data were collected electronically and compared to data acquisition and visual scoring using an EMBLETTA(®) GOLD polygraph. Statistics were only descriptive. RESULTS: Recordings were performed with six different CPAP machines and three different interfaces (full facemask, nasal pillow, nasal mask). The median [Q1; Q3] absolute difference in CPAP treatment duration between NOWAPI(®) and polygraphy was of 1.0 min [0.0; 12.0], corresponding to a relative difference of 0.21 % [0.0; 2.2] (Per Protocol data set, n = 20). NOWAPI(®) tended to underestimate residual AHI in a magnitude of two events per hour as compared to polygraphy. The device was well tolerated and the patient satisfaction was good. CONCLUSIONS: This clinical study confirmed prior bench tests, showing that NOWAPI(®) estimate of CPAP treatment duration was clinically acceptable and in agreement with polygraphy. Although a limited number of OSAS patients treated by CPAP were included, relevant findings for the device improvement were identified. Trial Registration ClinicalTrials.gov identifier: NCT01441622. The study was funded by Air Liquide HealthCare.

Airway morphology from high resolution computed tomography in healthy subjects and patients with moderate persistent asthma.

Models of the human respiratory tract developed in the past were based on measurements made on human tracheobronchial airways of healthy subjects. With the exception of a few morphometric characteristics such as the bronchial wall thickness (WT), very little has been published concerning the effects of disease on the tree structure and geometrical features. In this study, a commercial software package was used to segment the airway tree of seven healthy and six moderately persistent asthmatic patients from high resolution computed tomography images. The process was assessed with regards to the treatment of the images of the asthmatic group. The in vivo results for the bronchial length, diameter, WT, branching, and rotation angles are reported and compared per generation for different lobes. Furthermore, some popular mathematical relationships between these morphometric characteristics were examined in order to verify their validity for both groups. Our results suggest that, even though some relationships agree very well with previously published data, the compartmentalization of airways into lobes and the presence of disease may significantly affect the tree geometry, while the tree structure and airway connectivity is only slightly affected by the disease.

Daily soluble aspirin and prevention of colorectal adenoma recurrence: one-year results of the APACC trial.

BACKGROUND & AIMS: Epidemiologic and experimental studies have suggested that aspirin intake reduces the risk for colorectal carcinogenesis. However, the available data are not sufficient to serve as the basis for firm recommendations. METHODS: We randomly assigned 272 patients with a history of colorectal adenomas (at least one more than 5 mm in diameter, or more than 3) to daily lysine acetylsalicylate (160 or 300 mg/day) or placebo for 4 years. The primary end points were adenoma recurrence after 1 and 4 years. These results are those of the year 1 colonoscopy. RESULTS: Among the 238 patients who completed the year 1 colonoscopy, at least one adenoma was observed in 38 patients of the 126 (30%) in the aspirin group and in 46 of the 112 (41%) in the placebo group; relative risk was 0.73 (95% confidence interval [CI]: 0.52-1.04; P = 0.08). At least one adenoma of more than 5 mm diameter was observed in 13 patients (10%) in the aspirin group and 26 (23%) in the placebo group (P = 0.01). The corresponding numbers for adenomas more than 10 mm in diameter were one (1%) and 7 (6%) (P = 0.05). Stepwise regression showed that independent factors associated with lower adenoma recurrence are aspirin treatment (adenoma >5 mm, P = 0.01), absence of personal history of adenoma before the entry colonoscopy (P = 0.01), and initial adenomatous polyp burden less than 10 mm (P = 0.001). CONCLUSIONS: Daily soluble aspirin is associated with a reduction in the risk for recurrent adenomas found at colonoscopy 1 year after starting treatment.