Worsening of obstructive sleep apnea associated with catheter-related superior vena cava syndrome

There is growing evidence that fluid accumulation in the neck contributes to the pathogenesis of obstructive sleep apnea (OSA). We describe a case of catheter-related superior vena cava (SVC) thrombosis revealed by rapid onset of typical symptoms of OSA. A marked improvement in OSA severity was observed after central venous catheter removal, anticoagulant therapy, and SVC angioplasty

Le suivi pratique des patients sous pression positive continue

The therapeutic follow-up is a decisive factor of the success of a long course treatment by continuous positive airway pressure (CPAP). The effectiveness of this treatment on both symptoms and complications must be regularly verified. Polysomnography with CPAP could be necessary in order to check out the efficacy of this treatment and/or to find an associated diagnosis when symptoms persist, particularly a diurnal drowsiness, which is the main therapeutic target in obstructive sleep apnea syndrome (OSAS). The secondary effects that are likely to compromise the compliance of CPAP treatment must be resolved, particularly the nasal intolerance, which are enhanced by mask leakages and often corrected by using heated humidity with CPAP delivery systems. The efficacy of CPAP on both diurnal drowsiness and hypertension is related to the compliance of this treatment which must be regularly verified, at the same time that the clinical evaluation. The data obtained from the device\u27s memory give information concerning the number of hours day to day, in which the CPAP device was running at the prescribed pressure. The first months with CPAP are decisive to avoid a failure of the treatment at long term. This period must be closely monitored by both the physician and the home care provider. Patients should use the CPAP at least 3–4 h by night and all possible means should be used to obtain a maximal compliance. Therapeutic educational programs could help to reach this goal

Long-term outcome of noninvasive positive pressure ventilation for obesity hypoventilation syndrome

BACKGROUND: Few data are available on the long-term outcome of noninvasive positive pressure ventilation (NPPV) for obesity hypoventilation syndrome (OHS). This study was designed to determine long-term survival, treatment adherence, and prognostic factors in patients with OHS in whom NPPV was initiated in an acute setting vs under stable clinical conditions.METHODS: One hundred thirty consecutive patients with OHS (56 women) who started NPPV between January 1995 and December 2006 either under stable conditions (stable group, n = 92) or during ICU management of acute hypercapnic exacerbation (acute group, n = 38) were retrospectively analyzed. RESULTS: Arterial blood gases and the Epworth sleepiness scale were both significantly improved after 6 months of NPPV. With a mean follow-up of 4.1 +/- 2.9 years, 24 (18.5%) patients died and 24 (18.5%) discontinued NPPV. On Kaplan-Meier analysis, 1-, 2-, 3-, and 5-year survival probabilities were 97.5%, 93%, 88.3%, and 77.3%, respectively. Mortality was lower than that described in a previous series of patients with untreated OHS. Supplemental oxygen therapy was the only independent predictor of mortality. The probability of continuing NPPV was 80% at 3 years with a high rate of daily use ( > 7 h). Female sex was predictive of lower long-term adherence to NPPV. The acute and stable groups did not differ in terms of arterial blood gases and Epworth sleepiness scale at 6 months, long-term survival, and treatment adherence. CONCLUSIONS: The results of this study support long-term NPPV as an effective and well-tolerated treatment of OHS whether initiated in the acute or chronic setting

Microvascular endothelial function in obstructive sleep apnea: Impact of continuous positive airway pressure and mandibular advancement

ObjectivesEndothelial dysfunction has been proposed as a potential mechanism implicated in the pathogenesis of cardiovascular complications of obstructive sleep apnea syndrome (OSAS). This study aimed to evaluate the microvascular endothelial function (MVEV) in OSAS and the impact on MVEF of 2 months of treatment with continuous positive airway pressure (CPAP) and mandibular advancement device (MAD). Methods Microvascular reactivity was assessed using laser Doppler flowmetry combined with acetylcholine (Ach) and sodium nitroprusside (SNP) iontophoresis in 24 OSAS patients and 9 control patients. In 12 of the 24 OSAS patients, microvascular reactivity was reassessed after 2 months of CPAP and MAD using a randomized cross-over design. Results Ach-induced vasodilation was significantly lower in OSAS patients than in matched controls and correlated negatively with apnea hypopnea index (r = −0.49, p < 0.025) and nocturnal oxygen desaturations (r = −0.63, p < 0.002). Ach-induced vasodilation increased significantly with both CPAP and MAD. The increase in Ach-induced vasodilation under OSAS treatment correlated with the decrease in nocturnal oxygen desaturations (r = 0.48, p = 0.016). Conclusion Our study shows an impairment of MVEF in OSAS related to OSAS severity. Both CPAP and MAD treatments were associated with an improvement in MVEF that could contribute to improve cardiovascular outcome in OSAS patients

Titrated mandibular advancement versus positive airway pressure for sleep apnoea

The aim of this study was to compare mandibular advancement device (MAd) therapy and continuous positive airway pressure (CPAP) for obstructive sleep apnoea/hypopnoea syndrome (OSAHS) after one-night polysomnographic (PSG) titration of both treatments. 59 OSAHS patients (apnoea/hypopnoea index (AHI): 34±13 events·h−1; Epworth scale: 10.6±4.5) were included in a crossover trial of 8 weeks of MAd and 8 weeks of CPAP after effective titration. Outcome measurements included home sleep study, sleepiness, health-related quality of life (HRQoL), cognitive tests, side-effects, compliance and preference. The median (interquartile range) AHI was 2 (1–8) events·h−1 with CPAP and 6 (3–14) events·h−1 with MAd (p<0.001). Positive and negative predictive values of MAd titration PSG for treatment success were 85% and 45%, respectively. Both treatments significantly improved subjective and objective sleepiness, cognitive tests and HRQoL. The reported compliance was higher for MAd (p<0.001) with >70% of patients preferring this treatment. These results support titrated MAd as an effective therapy in moderately sleepy and overweight OSAHS patients. Although less effective than CPAP, successfully titrated MAd was very effective at reducing the AHI and was associated with a higher reported compliance. Both treatments improved functional outcomes to a similar degree. One-night titration of MAd had a low negative predictive value for treatment success

Influence of micropaticles harvested from patients affected by obstructive sleep apnea syndrome on endothelial function and vascular reactivity

Obstructive sleep apnea syndrome (OSAS) is a highly prevalent disease characterized by recurrent episodes of partial or complete obstruction of the upper airways during sleep, leading to oxygen desaturation, sleep fragmentation and clinical endothelial dysfunction. Microparticles (MPs) are membrane vesicles released during cell activation and apoptosis. Elevated levels of circulating MPs have been detected in pathologies associated with vascular alterations. We investigated the effects of MPs on endothelial function and vascular reactivity in OSAS. Blood samples were obtained either from 38 OSAS patients without any other cardiovascular comorbidities and 23 healthy subjects. A desaturation index above 10 per hour defined OSAS patients. MPs concentration and origin were assessed using flow cytometer. Male Swiss mice were injected i.v. with MPs from OSAS or healthy subjects, or with saline solution, and sacrified after 24hours. Endothelial function and vascular reactivity were studied on aortic rings and small mesenteric resistance (SMA) arteries by myography and arteriography, respectively. Patients with OSAS did not display increased circulating levels of MPs compared to healthy subjects including those from pro-coagulant, platelet, endothelial, leukocyte and erythrocyte origins. Interestingly, MPs from granulocytes and activated leukocytes were significantly enhanced in OSAS patients. Activated leukocyte MPs positively correlated with oxygen desaturation index. In aorta, MPs from OSAS patients but not those from healthy subjects significantly reduced endothelium-dependent relaxation to acetylcholine. MPs from OSAS increased sensitivity of the aorta in response to serotonin that was greater compared to the effect of MPs from healthy subjects. In SMA, MPs from OSAS but not those from healthy subjects impaired flow-induced dilation without any effect on myogenic tone. Although SMA from mice treated with healthy subjects MPs did not affect flow-induced dilation, these vessels showed a reduced prostacyclin-component that was completely compensated by the NO-component of the response. The endothelial dysfunction induced by MPs from OSAS was caused by the reduction of both NO- and prostacyclin- but not the endothelium-derived hyperpolarizing factor-components of the response in SMA. These data provide evidence that circulating MPs from OSAS patients influence both endothelial function and vascular reactivity

Nocturnal release of leukocyte-derived microparticles in males with obstructive sleep apnoea

Multiple pathophysiological mechanisms have been proposed to contribute to the increased cardiovascular morbidity in obstructive sleep apnoea (OSA), including autonomic dysfunction, inflammation, oxidative stress and endothelial dysfunction 1. Microparticles (MPs) are small membrane vesicles that are shed from circulating cells or from the components of the vessel wall in response to activation and apoptosis. There is growing evidence in support of a potential role of MPs in the field of cardiovascular diseases. Increased levels of MPs derived from various cell types are found in patients at risk of cardiovascular diseases 2. By modulating inflammation, coagulation, vasomotor reactivity and angiogenesis, MPs might directly contribute to cardiovascular diseases 2. Recent case–control studies suggest a potential involvement of MPs in OSA-associated cardiovascular morbidity 3–6. An increase in morning levels of MPs derived from activated leukocytes has been demonstrated in otherwise healthy male OSA patients with marked nocturnal desaturations 5. In vitro, nitric oxide (NO) production by endothelial cells incubated with MPs from OSA patients correlates negatively with circulating levels of activated leukocyte-derived MPs 5. Ex vivo, mice previously injected with MPs from OSA patients display endothelial dysfunction, reduced endothelial NO release and increased adhesion molecule expression 5

Mandibular Advancement for Obstructive Sleep Apnea: Dose Effect on Apnea, Long-Term Use and Tolerance

Background: Previous studies have documented an effect of mandibular advancement (MA) on pharyngeal airway size and collapsibility. Objectives: We aimed to describe the course of the apnea-hypopnea index (AHI) and the snoring index (SI) during progressive MA and to evaluate the long-term efficacy, tolerance and usage of MA therapy after progressive MA titration in sleep apnea patients. Methods: Sixty-six patients with obstructive sleep apnea syndrome underwent sequential sleep recordings during progressive MA titration. Long-term effectiveness, compliance and side effects of oral appliance (OA) in the titrated position were evaluated by questionnaires. Results: OA therapy was started at 80% of the maximum MA. Seventy percent of the patients had only one increment in MA with a marked decrease in mean AHI from 36 to 10. In the remaining cases, further increments in MA were associated with a progressive reduction in AHI and an increase in the number of patients responding to treatment. OA in the titrated position resulted in a 70% decrease in AHI, with 54% of patients showing complete responses, 29% partial responses and 17% no response. Daytime sleepiness and quality of life improved, too. Seventeen months after the start of treatment, 82% of the patients declared that they were still using OA almost all nights. Reported side effects including subjective occlusal changes were frequent but mild. Conclusions: Improvement in AHI during OA is dependent on the amount of MA. Sequential sleep recordings facilitate MA titration. Long-term MA therapy in the titrated position is effective and well tolerated. Reported side effects are frequent but mild