Upper airway obstruction during sleep in adults. Laboratory and home assessment

Ce travail présente une contribution personnelle à l’étude des phénomènes obstructifs au niveau de la voie aérienne supérieure et l’intègre dans une perspective plus large. Sont successivement abordés et discutés :
- les relations entre respiration et sommeil, et particulièrement les éléments anatomiques et fonctionnels qui interviennent dans le maintien d’une perméabilité pharyngée au cours des différents états de vigilance ;
les conséquences cliniques de l’obstruction de la voie aérienne supérieure pendant le sommeil, les mécanismes de cette obstruction et les différentes modalités thérapeutiques ; le traitement par pression positive continue par voie nasale, dont nous avons une large expérience, est particulièrement détaillé ;
- la méthode d’étude de la respiration au cours du sommeil en laboratoire ; c’est-à-dire la polysomnographie ; nous discutons particulièrement, la synthèse et la présentation des résultats que nous avons choisies afin de mettre en évidence les relations entre les multiples données cardiorespiratoires et les stades de sommeil ;
- les différents moyens d’études ambulatoires ; leurs aspects techniques et leur intérêt dans le dépistage et le suivi des patients présentant de tels problèmes respiratoires durant le sommeil sont passés en revue.

Over the past decade, Upper Airway Obstruction during Sleep has been the focus of major medical interest.
How this condition has so long eluded medical attention seems astonishing in view of its prevalence, of the multiple cardio-vascular and neuropsychological sequelae and the associated mortality. One reason of this fact is perhaps that the two common symptoms associated with this condition – snoring and daytime sleepiness – have long been the subject of mirth and not considered worthy of medical advice.
The acknowledgement of this new condition has been the starting point of the development of new tools able to assess sleeping and breathing and of the establishment of “Sleep Disorders Centers”.
As often in the medical field, pathophysiological studies of upper airway occlusion during sleep have stimulated basic work on the physiology of breathing during sleep. Important new concepts have emerged. Finally various treatment modalities, sometimes with spectacular results, have been proposed.
Since 1979, I have been fortunate to be involved in these exciting developments together with respiratory and nose-throat physicians, in this institution.
This thesis will integrate my own contribution in a broader perspective and examine the methods available in order to refine the clinical diagnosis, contribute to a better understanding of the pathogenesis and of the natural history of upper airway obstruction during sleep, and assess therapeutic interventions.
My personal contribution encompasses the following points :
- standardization of the technical conditions, data analysis and result display of cardiorespiratory sleep studies (polysomnography) in clinical setting.
- demonstration of the usefulness of ambulatory wrist activity monitoring in evaluating sleep disturbance and therapeutic effects in patients with sleep apnea syndrome.
- publication of the first Belgian case report of a patient with sleep apnea syndrome and his spectacular treatment by tracheostomy.
- description of unusual polysomnographic features of patients with a clinical syndrome of sleep apnea but without complete apnea.
- demonstration of the modifications in ventilatory response to CO2 following tracheostomy in obstructive sleep apnea.
- proof of the eventual cure of sleep apnea syndrome after long-term nasal continuous positive airway pressure therapy and weight loss, in some patients with a severe form of the syndrome.
- assessment of the role of nasal and pharyngeal structural abnormalities in upper airway obstruction during sleep and the benefit that ca be expected from surgery at this level.
- study of anatomic and functional features observed in snorers with and without apnea