Oscillating Positive Airway Pressure Versus CPAP for the Treatment of Obstructive Sleep Apnea

Although continuous positive airway pressure (CPAP) is the most effective therapy for obstructive sleep apnea (OSA), it is not always well tolerated by the patients. Previous physiological studies showed that pressure oscillations applied to the pharynx could activate upper airway muscles, but it is not clear whether these pressure oscillations could be tolerated during sleep in OSA patients. The aim of this study was to assess the tolerance of oscillating positive airway pressure (O-PAP) (a CPAP device delivering high-frequency pressure oscillations to the upper airway) compared to CPAP. Fourteen OSA patients currently on CPAP [age 59.9 ± 10.1 years old, BMI 34.8 ± 7.2 kg/m(2), initial apnea-hypopnea index (AHI): 58.7 ± 25.2 events/h] used O-PAP or CPAP on two consecutive nights under polysomnography, in a single-blind randomized crossover design to assess sleep quality. A subtherapeutic pressure (70% of the optimal titrated pressure) was applied in both conditions and the residual AHI with each technique was also compared. There was no difference in measured or perceived sleep quality between the two treatment modalities (sleep efficiency 90.0% versus 88.1%, p = 0.54). Despite the small sample, we also found a trend toward a decrease in residual respiratory events with O-PAP compared to CPAP (median AHI 14.3 versus 20.5/h, p = 0.194). The good tolerance of O-PAP and the positive trend toward a reduction in residual AHI should stimulate further research on the effects of O-PAP in OSA patients

Prevalence of sleep-disordered breathing in the general population: the HypnoLaus study.

BACKGROUND: Sleep-disordered breathing is associated with major morbidity and mortality. However, its prevalence has mainly been selectively studied in populations at risk for sleep-disordered breathing or cardiovascular diseases. Taking into account improvements in recording techniques and new criteria used to define respiratory events, we aimed to assess the prevalence of sleep-disordered breathing and associated clinical features in a large population-based sample. METHODS: Between Sept 1, 2009, and June 30, 2013, we did a population-based study (HypnoLaus) in Lausanne, Switzerland. We invited a cohort of 3043 consecutive participants of the CoLaus/PsyCoLaus study to take part. Polysomnography data from 2121 people were included in the final analysis. 1024 (48%) participants were men, with a median age of 57 years (IQR 49-68, range 40-85) and mean body-mass index (BMI) of 25·6 kg/m(2) (SD 4·1). Participants underwent complete polysomnographic recordings at home and had extensive phenotyping for diabetes, hypertension, metabolic syndrome, and depression. The primary outcome was prevalence of sleep-disordered breathing, assessed by the apnoea-hypopnoea index. FINDINGS: The median apnoea-hypopnoea index was 6·9 events per h (IQR 2·7-14·1) in women and 14·9 per h (7·2-27·1) in men. The prevalence of moderate-to-severe sleep-disordered breathing (≥15 events per h) was 23·4% (95% CI 20·9-26·0) in women and 49·7% (46·6-52·8) in men. After multivariable adjustment, the upper quartile for the apnoea-hypopnoea index (>20·6 events per h) was associated independently with the presence of hypertension (odds ratio 1·60, 95% CI 1·14-2·26; p=0·0292 for trend across severity quartiles), diabetes (2·00, 1·05-3·99; p=0·0467), metabolic syndrome (2·80, 1·86-4·29; p<0·0001), and depression (1·92, 1·01-3·64; p=0·0292). INTERPRETATION: The high prevalence of sleep-disordered breathing recorded in our population-based sample might be attributable to the increased sensitivity of current recording techniques and scoring criteria. These results suggest that sleep-disordered breathing is highly prevalent, with important public health outcomes, and that the definition of the disorder should be revised. FUNDING: Faculty of Biology and Medicine of Lausanne, Lausanne University Hospital, Swiss National Science Foundation, Leenaards Foundation, GlaxoSmithKline, Ligue Pulmonaire Vaudoise

Angioleiomyoma of the small intestine – a rare cause of gastrointestinal bleeding

<p>Abstract</p> <p>Background</p> <p>Benign tumors are a rare cause of gastrointestinal hemorrhage of which angioleiomyomas constitute a very small minority. They have been reported in literature to present with volvulus, bleeding or intussusceptions.</p> <p>Case presentation</p> <p>An interesting case of a patient presenting with gastrointestinal bleeding from an underlying angioleiomyoma is discussed along with its management options.</p> <p>Conclusion</p> <p>Angioleiomyoma though rare can be managed successfully by surgical and/or minimally invasive endovascular procedures.</p

Man and the Last Great Wilderness: Human Impact on the Deep Sea

The deep sea, the largest ecosystem on Earth and one of the least studied, harbours high biodiversity and provides a wealth of resources. Although humans have used the oceans for millennia, technological developments now allow exploitation of fisheries resources, hydrocarbons and minerals below 2000 m depth. The remoteness of the deep seafloor has promoted the disposal of residues and litter. Ocean acidification and climate change now bring a new dimension of global effects. Thus the challenges facing the deep sea are large and accelerating, providing a new imperative for the science community, industry and national and international organizations to work together to develop successful exploitation management and conservation of the deep-sea ecosystem. This paper provides scientific expert judgement and a semi-quantitative analysis of past, present and future impacts of human-related activities on global deep-sea habitats within three categories: disposal, exploitation and climate change. The analysis is the result of a Census of Marine Life – SYNDEEP workshop (September 2008). A detailed review of known impacts and their effects is provided. The analysis shows how, in recent decades, the most significant anthropogenic activities that affect the deep sea have evolved from mainly disposal (past) to exploitation (present). We predict that from now and into the future, increases in atmospheric CO2 and facets and consequences of climate change will have the most impact on deep-sea habitats and their fauna. Synergies between different anthropogenic pressures and associated effects are discussed, indicating that most synergies are related to increased atmospheric CO2 and climate change effects. We identify deep-sea ecosystems we believe are at higher risk from human impacts in the near future: benthic communities on sedimentary upper slopes, cold-water corals, canyon benthic communities and seamount pelagic and benthic communities. We finalise this review with a short discussion on protection and management methods

Chemisorbed Oxygen at Pt(111): a DFT Study of Structural and Electronic Surface Properties

Simulations based on density functional theory are used to study the electronic and electrostatic properties of a Pt(111) surface covered by a layer of chemisorbed atomic oxygen. The impact of the oxygen surface coverage and orientationally ordered interfacial water layers is explored. The oxygen adsorption energy decreases as a function of oxygen coverage due to the lateral adsorbate repulsion. The surficial dipole moment density induced by the layer of chemisorbed oxygen causes a positive shift of the work function. In simulations with interfacial water layers, ordering and orientation of water molecules strongly affect the work function. It is found that the surficial dipole moment density and charge density are roughly linearly dependent on the oxygen surface coverage. Moreover, we found that water layers exert only a small impact on the surface charging behavior of the surface

Syndrome d'apnées du sommeil positionnel [Positional obstructive sleep apnea syndrome].

Obstructive sleep apnea (OSA) tends to worsen on the supine posture due to the effect of gravity on tongue position. In some cases, OSA is present exclusively on the supine posture (exclusive postural OSA). These patients may benefit from positional therapy (PT), which aim is to prevent sleep in the supine posture using different types of devices. Before opting for this therapeutic option, a sleep study with PT should be perform in order to confirm its efficacy and assess the patients' tolerance. Because the efficacy of PT is inferior to continuous positive airway pressure (CPAP), the latter treatment remains the first line of therapy. Also, the discomfort of the existing devices appears to limit the long term use of PT. Further studies assessing the long term effects of PT on metabolic and neurocognitive outcomes are needed

Bioénergétique et échange cardio-respiratoires lors de deux situations de combat en judo et en kendo

Le but de ce travail était de comparer la consommation d'oxygène et les réponses cardiorespiratoires lors de deux situations de combat et de situer ces niveaux d'exigences métaboliques par rapport à un effort maximal aérobie réalisé au laboratoire. Huit jeunes débutants masculins volontaires, âgés de 22,8±2,9 ans, ont réalisé une épreuve d'effort maximale sur ergocycle et ont participé, contre le même adversaire, à deux situations de combat en judo et en kendo selon un ordre aléatoire à une semaine d'intervalle. La consommation d'oxygène et les réponses cardioventilatoires ont été mesurées respectivement, au repos, à chaque minute pendant 3 min effectives de combat et lors de l'épreuve d'effort maximale, à l'aide d'un système portable d'analyse de gaz par télémétrie (Cosmed K2). En judo le porteur du matériel devait mettre son adversaire à terre tout en restant debout. Pour l'adversaire il s'agissait de soulever et de décoller son adversaire du sol. En kendo, la situation consistait à combattre à l'aide d'un bâton selon des règles adaptées du Kendo fédéral. Les résultats ne montrent pas de différence significative pour l'ensemble des variables énergétiques et cardiorespiratoires mesurées au repos. Au cours de la 3ème min des combats en judo et en kendo, respectivement, la consommation d'oxygène (78 et 65%), la fréquence cardiaque (89 et 86%), le pouls d'oxygène ( VO2/FC), la ventilation (69 et 60%), la capacité vitale et la fréquence respiratoire présentent des hauts pourcentages par rapport aux valeurs maximales mais ne diffèrent pas statistiquement. En conclusion, cette étude montre qu'en situation réelles de pratique, la consommation d'oxygène et les réponses cardioventilatoires sont importantes en fin de combat mais restent comparables entre le judo et le kendo en dépit d'une forme de pratique différente

Sleep-disordered breathing and daytime postural stability.

Postural stability depends on the coordination of the central nervous system with visual sense, proprioceptive and vestibular information. Sleep deprivation has been shown to affect this function. The objective of our study was to assess the effects of sleep-disordered breathing (SDB) on postural stability. 158 subjects referred for suspected SDB had an overnight sleep study and were placed on a posturographic platform in late afternoon. This platform allows measuring the centre of pressure (CoP) oscillations and to calculate: total displacement of CoP in X and Y axes, mean speed of CoP displacement and the length as function of surface (LFS) ratio (length of CoP displacement/surface of CoP trajectory). 98 men and 60 women were included. Mean age±SD was 45.4±5.5 years old, body mass index (BMI) 27.5±5.6 kg/m(2) and apnoea-hypopnoea index (AHI) 13.6±16.1/h. AHI was &lt;5/h in 64 (41%) subjects, 5-15/h in 43 (27%), 15-30/h in 30 (19%) and &gt;30/h in 21 (13%). In patients with an AHI &gt;5/h versus AHI &lt;5/h, we observed an important increase in LFS (+21%, p&lt;0.001), in XY length (+23%, p&lt;0.001) and in mean speed (+23%, p&lt;0.001). After controlling for age, BMI and sleepiness (Epworth) in multivariate regression models, there was a positive association between all nocturnal breathing parameters (specifically: mean SpO2, AHI, oxygen desaturation index 3% and % time with SpO2 &lt;90%) and the main stability outcomes (all p&lt;0.05). SDB severity, especially the mean nocturnal SpO2 level, is associated with impaired daytime postural stability

Scoring criteria for portable monitor recordings: a comparison of four hypopnoea definitions in a population-based cohort.

RATIONALE: Limited-channel portable monitors (PMs) are increasingly used as an alternative to polysomnography (PSG) for the diagnosis of obstructive sleep apnoea (OSA). However, recommendations for the scoring of PM recordings are still lacking. Pulse-wave amplitude (PWA) drops, considered as surrogates for EEG arousals, may increase the detection sensitivity for respiratory events in PM recordings. OBJECTIVES: To investigate the performance of four different hypopnoea scoring criteria, using 3% or 4% oxygen desaturation levels, including or not PWA drops as surrogates for EEG arousals, and to determine the impact of measured versus reported sleep time on OSA diagnosis. METHODS: Subjects drawn from a population-based cohort underwent a complete home PSG. The PSG recordings were scored using the 2012 American Academy of Sleep Medicine criteria to determine the apnoea-hypopnoea index (AHI). Recordings were then rescored using only parameters available on type 3 PM devices according to different hypopnoea criteria and patients-reported sleep duration to determine the 'portable monitor AHIs' (PM-AHIs). MAIN RESULTS: 312 subjects were included. Overall, PM-AHIs showed a good concordance with the PSG-based AHI although it tended to slightly underestimate it. The PM-AHI using 3% desaturation without PWA drops showed the best diagnostic accuracy for AHI thresholds of ≥5/h and ≥15/h (correctly classifying 94.55% and 93.27% of subjects, respectively, vs 80.13% and 87.50% with PWA drops). There was a significant but modest correlation between PWA drops and EEG arousals (r=0.20, p=0.0004). CONCLUSION: Interpretation of PM recordings using hypopnoea criteria which include 3% desaturation without PWA drops as EEG arousal surrogate showed the best diagnosis accuracy compared with full PSG

Oxygen uptake and cardiorespiratory responses during selected fighting techniques in judo and kendo

International audienceThe goal of this study was to compare oxygen uptake (VO2) and cardiorespiratory responses during two selected fighting techniques in kendo and judo and to express the effort levels required to those measured during maximal incremental exercise test. Eight male, aged 22.8 ± 2.9 years, with a moderate level of ability in fighting sport, volunteered for the study. They randomly performed once a week a maximal exercise test on cycle ergometer and a judo and kendo fighting sessions, respectively, against the same adversary. VO2 and cardiorespitory responses were measured at rest, at each minute during 3 min of fighting and during a maximal incremental exercise test, with a Cosmed K2 telemetric gas exchanges analyser. Aerobic energy expenditure was calculated during the 3 fighting minutes as the difference between VO2 determined at each minute and VO2 at rest. The judo technique required a subject wearing the cosmed K2 to remain upright and throw his adversary down. For the adversary, it consists to raise the subject from ground. The kendo technique consists of fighting with stick according to an adapted federal Kendo rule. At rest, there was no difference between judo and kendo in all cardiorespiratory variables including VO2. The VO2 reached a high percentage of the maximal value at the 3rd minute of fighting but did not differ, respectively, between judo and kendo [1st min : 14.79 ± 5.05 (28%) vs. 17.75 ± 3.8 (34%), 2nd min : 35.39 ± 12.85 (68%) vs. 34.38 ± 5.54 (66%) and 3rd min : 40.73 ± 4.05 (78%) vs. 34.14 ± 6.13 (65%) ml.min-1.kg.-1]. Analysis of ventilatory gas exchange lead to similar results with largest percentage for judo and kendo compared with the VO2 max test respiratory variables at the 3rd minute for pulmonary ventilation [1st min : 33.31 ± 10.89 (32%) vs. 38.55 ± 4.2 (37%), 2nd min : 63.78 ± 16.64 (62%) vs. 59.01 ± 11.15 (57%) and 3rd min : 71.51 ± 15.87 (69%) vs. 61.68 ± 12.55 (60%) min-1], tidal volume [1st min : 1.31 ± 0.40 vs. 1.33 ± 0.48, 2nd min : 1.94 ± 0.49 vs. 1.86 ± 0.41 and 3rd min : 2.08 ± 0.5 vs. 1.97 ± 0.39 l], and breathing frequency [1st min : 26.91 ± 8.23 vs. 2.62 ± 7.02, 2nd min : 33.99 ± 6.64 vs. 32.96 ± 5.97 and 3rd min : 35.60 ± 6.64 vs 32.72 ± 5.73 cycle.min-1]. Cardiac response also reached high percentages at the 3rd minute but values remain identical for heart rate [1st min : 130 ± 22 (70%) vs. 137 ± 21 (73%), 2nd min : 161 ± 18 (86%) vs. 157 ± 13 (84%) and 3rd min : 166 ± 18 (89%) vs. 162 ± 13 (86%) beat.min-1], and oxygen pulse [1st min : 8 ± 2.1 vs. 9.4 ± 2.4, 2nd min : 15.62 ± 3.88 vs. 15.84 ± 2.60] and 3rd min : 17.85 ± 3.24vs. 15.22 ± 2.68 ml.kg-l.beat-1]. These results indicate that, in practical conditions, the two selected fighting of judo and kendo require a similar and large oxygen uptake and cardiorespiratory response