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    ABSTRACT: Objective To construct an algorithm for the diagnosis of sleep apnea/hypopnea syndrome (SAHS) based on the opti-mized sequential use of nocturnal pulse oximetry and respi-ratory polygraphy (AutoSet®, AS) in patients suspected of SAHS Methods Simultaneous performance of pulse oximetry and AS in 145 patients highly suspected of SAHS (at least two of the following signs or symptoms: chronic snoring, ob-servations of repeated apneic events, and abnormal daytime drowsiness). SAHS was diagnosed when the apnea/hypopnea index (AHI) was greater than or equal to 10, based on AS findings. The diagnostic algorithm was obtained by calcula-ting the prevalence of SAHS, calculating the best diagnostic cutoff point for a desaturation index greater than or equal to 4% (ID4%) based on the AHI; analyzing the positive predic-tive value (PPV) and negative predictive value (NPV) for the cutoff and the correlation and agreement between ID4% and the AHI depending on the presence and severity of SAHS Results The overall prevalence of SAHS was 83.4%. The best cutoff point was obtained using ID4% greater than or equal to 10 (sensitivity 82%; specificity 83%). The PPV and NPV for the prevalence calculated were 0.95 and 0.29, respectively. The correlation between ID4% and AHI was 0.84; overall agreement was 0.93. For patients who did not have SAHS, the PPV was 0.49, and the NPV was 0.35; both gradually increased in cases of mild, moderate and severe SAHS (to 0.90 and 0.95, respectively, for severe SAHS). Using these data we created a diagnostic algorithm accor-ding to which an ID4% greater than or equal to 30 for noc-turnal pulse oximetry (sensitivity 72%, specificity 100%) would indicate that AS testing would be unnecessary. An ID4% less than 30, on the other hand, would lead to further testing (AS, or polysomnography in the event of a negative AS), based on the high prevalence of SAHS in our series Conclusions The sequential use of nocturnal pulse oxi-metry and AS allows substantial savings of polysomnograp-hic testing in groups at high risk of SAHS
    Archivos de Bronconeumología 01/2003; 39(02):74-80. · 1.37 Impact Factor
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    ABSTRACT: Summary To establish literature-based values of control subjects in sleep medicine. These data should give a range for the interpretation of polysomnographic results. We systematically collected and pooled data of control subjects in different sleep studies. We calculated the weighted arithmetical mean of these data, i. e. the mean of the means of multiple studies, with consideration being given to the number of the individual values concerned. Since the data in the literature were not presented uniformly, we were not able to establish standard deviations. Reported sleep stages were accepted only when the and classification was applied. Arousals were accepted only if established in accordance with the criteria of the American Academy of Sleep Medicine. Whenever possible we calculated data broken down for age groups. Usable data were obtained from studies of between 10 and 1023 control subjects. The age range extended from infancy to 85 years. Data on sleep stages, sleep latencies, arousals, oxygen saturation, partial pressure of carbon dioxide, apneas and hypopneas were processed. Sleep latency and proportion of sleep stages are influenced by the first-night effect. The data reflect the current status. When more control data are published the tables will have to be updated. German Zusammenfassung Fragestellung Zur Beurteilung von polysomnographischen Messergebnissen sind Vergleichswerte von Untersuchungen von Kontrollpersonen erforderlich. Patienten und Methodik Schlafmedizinische Daten gesunder Kontrollpersonen, meist als Kontrollkollektiv verschiedenster Studien aufgeführt, wurden systematisch zusammengestellt. Anhand der Zahl der Untersuchten wurde das gewogene arithmetische Mittel berechnet (Mittelwert aus Mittelwerten einzelner Studien unter Berücksichtigung der Anzahl der zugrunde liegenden Einzelwerte). Da die Daten in unterschiedlichen Studien nicht einheitlich präsentiert werden, konnten für alle Messwerte zwar Mittelwerte, aber nicht Standardabweichungen oder Bereiche (Range) angegeben werden. Schlafstadien wurden dann übernommen, wenn die Einteilung nach Rechtschaffen und Kales erfolgte. Arousals sind nur aufgeführt bei Bestimmung gemäß den Kriterien der American Academy of Sleep Medicine. Sofern aus den Studien ersichtlich wurden die Referenzwerte in Altersklassen dekadenweise eingeteilt. Ergebnisse Die einzelnen Studien umfassen Werte von 10 bis 1023 Probanden. Der Bereich beginnt bei Säuglingen und endet bei 85 Jahren. Es werden Ergebnisse zu Schlafstadien, Schlaflatenzen, Arousals, Sauerstoffsättigung, Kohlendioxidpartialdruck und Apnoen sowie Hypopnoen präsentiert. Die Schlaflatenz sowie die Verteilung der Schlafstadien können erst nach einer Adaptionsnacht zuverlässig beurteilt werden. Schlussfolgerungen Die Daten fassen den augenblicklichen Stand zusammen. Bei Veröffentlichung neuerer umfangreicher Messergebnisse müssen die Tabellen aktualisiert werden.
    Somnologie - Schlafforschung und Schlafmedizin 01/2003; 7(1).
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    ABSTRACT: The objective of this study is to determine whether obstructive sleep apnea (OSA) is associated with reduced fetal growth, and whether nocturnal oxygen desaturation precipitates acute fetal heart rate changes. We performed a prospective observational study, screening 371 women in the second trimester for OSA symptoms. 41 subsequently underwent overnight sleep studies to diagnose OSA. Third trimester fetal growth was assessed using ultrasound. Fetal heart rate monitoring accompanied the sleep study. Cord blood was taken at delivery, to measure key regulators of fetal growth. Of 371 women screened, 108 (29%) were high risk for OSA. 26 high risk and 15 low risk women completed the longitudinal study; 14 had confirmed OSA (cases), and 27 were controls. The median (interquartile range) respiratory disturbance index (number of apnoeas, hypopnoeas or respiratory related arousals/hour of sleep) was 7.9 (6.1-13.8) for cases and 2.2 (1.3-3.5) for controls (p<0.001). Impaired fetal growth was observed in 43% (6/14) of cases, vs 11% (3/27) of controls (RR 2.67; 1.25-5.7; p = 0.04). Using logistic regression, only OSA (OR 6; 1.2-29.7, p = 0.03) and body mass index (OR 2.52; 1.09-5.80, p = 0.03) were significantly associated with impaired fetal growth. After adjusting for body mass index on multivariate analysis, the association between OSA and impaired fetal growth was not appreciably altered (OR 5.3; 0.93-30.34, p = 0.06), although just failed to achieve statistical significance. Prolonged fetal heart rate decelerations accompanied nocturnal oxygen desaturation in one fetus, subsequently found to be severely growth restricted. Fetal growth regulators showed changes in the expected direction- with IGF-1 lower, and IGFBP-1 and IGFBP-2 higher- in the cord blood of infants of cases vs controls, although were not significantly different. OSA may be associated with reduced fetal growth in late pregnancy. Further evaluation is warranted to establish whether OSA may be an important contributor to adverse perinatal outcome, including stillbirth.
    PLoS ONE 01/2013; 8(7):e68057. · 3.53 Impact Factor