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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Ventilatory drive and the apnea-hypopnea index in six-to-twelve year old children

Fregosi, Ralph, Quan, Stuart, Jackson, Andrew, Kaemingk, Kris, Morgan, Wayne, Goodwin, Jamie, Reeder, Jenny, Cabrera, Rosaria, Antonio, Elena January 2004 (has links)
BACKGROUND:We tested the hypothesis that ventilatory drive in hypoxia and hypercapnia is inversely correlated with the number of hypopneas and obstructive apneas per hour of sleep (obstructive apnea hypopnea index, OAHI) in children.METHODS:Fifty children, 6 to 12 years of age were studied. Participants had an in-home unattended polysomnogram to compute the OAHI. We subsequently estimated ventilatory drive in normoxia, at two levels of isocapnic hypoxia, and at three levels of hyperoxic hypercapnia in each subject. Experiments were done during wakefulness, and the mouth occlusion pressure measured 0.1 seconds after inspiratory onset (P0.1) was measured in all conditions. The slope of the relation between P0.1 and the partial pressure of end-tidal O2 or CO2 (PETO2 and PETCO2) served as the index of hypoxic or hypercapnic ventilatory drive.RESULTS:Hypoxic ventilatory drive correlated inversely with OAHI (r = -0.31, P = 0.041), but the hypercapnic ventilatory drive did not (r = -0.19, P = 0.27). We also found that the resting PETCO2 was significantly and positively correlated with the OAHI, suggesting that high OAHI values were associated with resting CO2 retention.CONCLUSIONS:In awake children the OAHI correlates inversely with the hypoxic ventilatory drive and positively with the resting PETCO2. Whether or not diminished hypoxic drive or resting CO2 retention while awake can explain the severity of sleep-disordered breathing in this population is uncertain, but a reduced hypoxic ventilatory drive and resting CO2 retention are associated with sleep-disordered breathing in 6-12 year old children.
2

Development and application of a physiological ventilation device test bench, capable of reproducing automatically respiratory profiles registered with ventilation polygraph / Développement et application d’un banc d’essai physiologique, capable de simuler automatiquement les profils respiratoires enregistrés par polygraphie ventilatoire

Liu, Shuo 13 December 2019 (has links)
Le syndrome d’apnée obstructive du sommeil affecte 6% à 17% de la population adulte. Le traitement de référence est la ventilation nocturne par une pression positive continue (PPC) fixe ou autopilotée afin de maintenir les voies aériennes ouvertes. L’efficacité de traitement des PPC autopilotées dépend des algorithmes et technologies pour détecter et qualifier les événements respiratoiresDes bancs d’essai ont été créés pour évaluer les PPC autopilotées en conditions comparables, en simulant des scénarios respiratoires composés de chaînes répétitives d’événements respiratoires. Les profils respiratoires simulés par les bancs d’essai précédents sont standardisés et simplifiés par rapport au profil respiratoire du patient.Pour tendre vers des essais plus réalistes, un nouveau banc d’essai physiologique permettant de reproduire automatiquement les profiles respiratoires à partir des données polygraphiques a été créé pendant cette thèse. Il a été validé en évaluant la simulation de scénarios respiratoires de différents phénotypes issus de 12 patients.Via ce banc d’essai, la précision de l’index d’apnée-hypopnée (IAH) résiduel fourni par PPC a été évalué, en comparant les IAH déterminés par 4 dispositifs de PPC (AirSense 10, DreamStation Auto, S.Box et Prisma 20A) avec ceux de polygraphie. Les résultats ont permis de quantifier les différences d’IAH afin d’aider les médecin à en tenir compte. / Obstructive sleep apnea syndrome affects 6% to 17% of adult population. The reference treatment is nocturnal ventilation via an either fixed or auto-titrating positive airway pressure (APAP) to maintain upper airway (UA) open. Treatment efficiency of APAP depends greatly on algorithms and technologies used for detecting and characterizing disordered breathing events (linked to UA obstruction or central command).Bench tests have been developed to evaluate APAP devices under the same conditions, by simulating respiratory scenarios composed of a repetitive string of several disordered breathing events registered from apneic patients or artificially designed.Therefore, breathing profiles simulated on benches are standardized and simplified, in comparison with patients’. To improve this disadvantage, a new physiological bench, which enables reproducing automatically a specific patient breathing profile from its polygraph recordings, has been created. It has been validated by simulating various breathing profiles issuing from 12 patients of different pathological phenotypes.Through this new bench, the accuracy of residual apnea hypopnea indices (AHI) determined by 4 APAP devices (AirSense 10, DreamStation Auto, S.Box and Prisma 20A) has also been investigated in comparison with polygraph scorings. The results would help physicians in clinical practice thanks to the quantification of AHI discrepancies between manufacturers.
3

Natt-till-natt-variation av andningshändelser vid nattlig andningsregistrering / Night-to-night-variability of respiratory events in polygraph testing

Bitar, Tala January 2023 (has links)
Sömnapné karaktäriseras av korta andningsuppehåll som inträffar under sömnen och resulterar i en störd nattsömn. Svårighetsgraden av sömnapné kan anges med hjälp av ett index som kallas för apné-hypopné index (AHI), där summan av alla andningsuppehåll divideras med den totala sömntiden. Vanligtvis sker sömnregistreringen under endast en natt men i denna studie ska registreringen ske under två nätter i stället. Syftet med studien är att undersöka skillnaden i AHI-värde och därmed skillnaden i den diagnostiserade svårighetsgraden av sömnapné mellan de två registreringstillfällen. Observationsstudien bestod av 25 patienter, varav 14 män, som blivit remitterade för sömnapnéutredning på Fysiologkliniken vid Västmanlands sjukhus Västerås. Sömnen registrerades i hemmet med hjälp av den ambulatoriska sömnregistreringsapparaten NOX T3s. All insamlad data analyserades manuellt i programmet NoxTurnal. Ett Wilcoxons signed-rank test med signifikansnivå 0,05 användes för att se om det förelåg signifikant skillnad i AHI-värde mellan de båda registreringarna. Den statistiska analysen visade ingen statistiskt signifikant skillnad i AHI mellan första respektive andra registreringen. På individnivå sågs smärre skillnader. För 3 av 25 patienter var skillnaderna mellan registreringarna sådana så att den kliniska handläggningen skulle ha kunnat förändras. / Sleep apnea is characterized by short pauses in breathing that occur during sleep and result in disrupted sleep. The severity of sleep apnea can be indicated by an index called the apnea-hypopnea index (AHI), where the sum of all breathing pauses is divided by the total sleep time. Typically, sleep monitoring occurs for only one night, but in this study, monitoring will take place over two nights. The purpose of the study is to investigate the difference in AHI value and therefore the difference in the diagnosed severity of sleep apnea between the two monitoring occasions. The study consisted of 25 patients, of whom 14 were men and 11 were women, referred for sleep apnea evaluation at the Physiology Clinic at Västmanland Hospital in Västerås. Sleep was recorded at home using the ambulatory sleep registration device NOX T3s. All data was manually analyzed using the NoxTurnal software program. A Wilcoxon signed-rank test with a significance level of 0,05 was used to determine if there was a significant difference. There was no statistically significant difference in AHI between the first and second recordings. On an individual level, minor differences were observed. For 3 out of 25 patients, the differences between the registrations were significant enough to potentially change the clinical management.
4

En jämförelse mellan respiratorisk polygrafi och perifer arteriell tonometri i diagnos av obstruktiv sömnapné / A comparison between Peripheral Arterial Tonometry and polygraphy in the diagnosis of Obstructive Sleep Apnea

Starck, Anton, Al-Obaidi, Marwah January 2019 (has links)
Bakgrund: Obstruktiv sömnapné (OSA) är en av de vanligaste kroniska sömnsjukdomarna. Sjukdomen kännetecknas av återkommande episoder med andningsuppehåll under sömn. Detta ligger till grund för dagsömnighet och utveckling av systemsjukdomar. Det finna goda behandlingsalternativ för OSA som CPAP (continuous positive airway pressure), bettskena och kirurgi. Respiratorisk polygrafi (hädanefter presenterad som ”polygrafi”) är standardmetoden i Sverige för att diagnosticera OSA. Perifer arteriell tonometri (PAT) är en alternativ metod. Det finns olika kriterier för tolkning av polygrafi. Detta gör det svårt att jämföra studier. Svenska sömnapnéregistret (SESAR) och berörda specialitetsföreningar har därför tagit fram svenska nationella diagnoskriterier för sömnapné, SESAR-kriterierna. Syfte: Syftet med studien var att utreda om indexvärdena, AHI (apné-hypopné index) och ODI (oxygen desaturation index) överensstämmer i totalen och i olika positioner (rygg och icke-rygg) mellan PAT och polygrafi (tolkad med SESAR-kriterierna), samt att undersöka om det föreligger någon systematisk skillnad mellan dem. Material och metod: Elva patienter registrerades med polygrafi (NOX-T3) och PAT(WatchPAT) under en och samma natt. Registreringarna tolkades med SESAR kriterierna och WatchPAT scoring guidelines. Resultat: PAT visade en stark positiv korrelation med polygrafi (Spearman’s rho=0,771–0,963). Slutsats: Ingen signifikant skillnad hittades mellan PAT och polygrafi. / Background: Obstructive sleep apnea (OSA) is the most common chronic sleep disorder. The disease is characterized by recurrent episodes of respiratory arrest during sleep. This is the basis for daytime sleepiness and development of common systemic diseases. There are good treatment options for OSA including CPAP (continuous positive airway pressure), mandibular advancement splints and surgery. Respiratory polygraphy (hereinafter referred to as “polyhraphy”) is the standard method in Sweden for diagnosing OSA. Peripheral arterial tononometry (PAT) is an alternative method. There are different criteria for interpretation of polygraphy, thus making it difficult to compare studies. Svenska sömnapnéregistret (SESAR) and relevant speciality associations have therefore developed a Swedish national diagnostic criterion for sleep apnea, the SESAR-criteria. Purpose: To investigate if PAT and polygraphy (interpreted with the SESAR-criteria), correspond in apnea-hypopnea index (AHI) and oxygen desaturation index (ODI) and if there is any systematic difference between the methods in different positions (supine and non-supine). Material and methods: Eleven patients were registered with polygraphy (NOX-T3) and PAT (WatchPAT) for one night. The registrations were interpreted with the SESAR-criteria and the WatchPAT scoring guidelines, respectively. Results: PAT showed a strong positive correlation with polygraphy (Spearman’s rho=0,771-0,963). Conclusion: No significant difference was found between methods.
5

Effekten av olika hypopné-kriterier med 4% och 3% desaturation på apné/hypopné index / The effect of different hypopnea-criteria with 4% and 3% desaturation on the apnea/ hypopnea index

Al-Daghiree, Jehan January 2020 (has links)
Syfte: Apné/hypopné index (AHI), antalet apnéer/hypopnéer per sömntimma, är den vanligaste parametern som används för att beskriva graden av sömnapné. Syftet med studien är att undersöka effekten av olika hypopnékriterier för AHI, med desaturationsnivå 3% eller 4% d.v.s. om det finns en signifikant skillnad i AHI vid användning av hypopnékriterier 3% jämfört med 4 %. Metod och material: Polygrafiska registreringar från 40 patienter analyserades retrospektivt. Hypopnéer definierades först som 30–90% minskning av luftflödet under >10 sekunder förknippat med 3% desaturation. Därefter definierades hypopnéer med 4% desaturation. Patentregistreringarna tolkades manuellt på Fysiologkliniken vid Västmanlands sjukhus Västerås. Resultat och slutsats: En signifikant skillnad föreligger i AHI vid användning av de olika hypopnékriterierna, (p <0,001). AHI varierade från medianvärdet 8,5 (2,9–17,6) för vid användning av tolkningskriterium 4% desaturation till 15,7 (6,5–24) vid användning av tolkningskriterium 3%. Det är viktig att följa de nya uppdaterade kriterierna från American Academy of Sleep Medicine och Svenska sömnapnéregistret för att kunna ställa rätt diagnos och behandling för patienten. / Purpose: The apnea/hypopnea index (AHI) is the most common parameter used to describe the severity of sleep apnea. The purpose of this study was to examine the effect of different oxygen desaturation levels (3% and 4%) on AHI i.e. if there is a significant difference in the AHI when using different hypopnea-criteria. Method and material: Polygraphic recordings of 40 patients were analyzed retrospectively. Hypopneas were first defined as 30-90% drop in airflow for >10 s associated with 3% oxygen desaturation. Then hypopneas were defined as with 4% oxygen desaturation. Results and conclusion: There is a significant difference in AHI when using different hypopnea criteria, i.e. 4% or 3% desaturation. AHI varied from 8,5 (2,9–17,6) when using hypopnea criteria 4% to 15,7 (6,5–24) when using 3%. It is important to follow the new updated criteria from the American Academy of Sleep Medicine and the Swedish Sleep Apnea Register in order to provide the right diagnosis and treatment for the patient.

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