Fixed-pressure CPAP versus auto-adjusting CPAP: comparison of efficacy on blood pressure in obstructive sleep apnoea, a randomised clinical trial.

Background: Millions of individuals with obstructive sleep apnoea (OSA) are treated by CPAP aimed at reducing blood pressure (BP) and thus cardiovascular risk. However, evidence is scarce concerning the impact of different CPAP modalities on BP evolution.

Methods: This double-blind, randomised clinical trial of parallel groups of patients with OSA indicated for CPAP treatment compared the efficacy of fixed-pressure CPAP (FP-CPAP) with auto-adjusting CPAP (AutoCPAP) in reducing BP.

Does oximetry contribute to the detection of apneic events? Mathematical processing of the SaO2 signal.

The purpose of this study was to assess the ability of continuous nocturnal oximetry to detect sleep apnea syndrome (SAS) and to recognize nonapneic oxyhemoglobin desaturations. Oxygen saturation oscillations, related to successive apneas in SAS or to apneic episodes in COPD or restrictive patients, were quantified using a new index: delta = 1/n sigma 1 n magnitude of delta(SaO2)/delta(t)(12-s intervals) Twenty-six patients (15 SAS, 8 COPD, and 3 restrictive patients) were included in a prospective study comparing nocturnal oximetry and polysomnography over 34 nights. In apneic patients, we found a strong correlation (r2 = 0.

[Can oximetry contribute to the detection of apnea? The use of a mathematical analysis of the oximetry signal].

The aim of this study was to test the efficacy of nocturnal oximetry as a means of continuous recording of SaO2 in the identification of apnoeic events in the recognition of non-apnoeic desaturation. The oscillations of SaO2 in relation to successive periods of apnoea during the course of the sleep apnoea syndrome (SAS) or with apnoeic episodes in patients with chronic airflow obstruction (BPCO) or restricted disease, were identified using a new delta index quantifying the variations of SaO2 during the night. 26 successive patients in whom there was an indication for nocturnal oximetry were included in a prospective study comparing nocturnal oximetry and polysomnography during 34 nights.

[Development of nocturnal desaturation in 35 patients with chronic obstructive bronchopneumopathy (COBP). Relation to functional and hemodynamic data].

35 patients with chronic airflow obstruction in a stable state were studied using nocturnal oximetry on two occasions with an interval of 25 +/- 10 months between them. First we studied the predicted value for the pulmonary function factors during the day to compare with nocturnal desaturation. On the second occasion we compared the progress of the desaturation indices and the outcome of the functional and hemodynamic data.