公开(公告)号：WO1995026680A1

公开(公告)日：1995-10-12

申请号：PCT/CA1995000179

申请日：1995-03-31

Applicant: UNIVERSITE LAVAL

Inventor： UNIVERSITE LAVAL ,  SERIES, Frederic ,  MARC, Isabelle

IPC: A61B05/097

CPC classification number: A61B5/083 ,  A61B5/7242 ,  A61B5/7264

Abstract: Inspiratory flow limitation (IFL) is involved in the pathophysiology of sleep-related breathing disorders. Since the definition of flow-limited cycle is based on a dissociation between flow and respiratory efforts, identification of IFL requires upper airway or intrathoracic pressure measurements. We examined the feasability and accuracy of the analysis of the flow-volume loop of a tidal breath in identifying IFL. The tidal volume was obtained by integration of the instantaneous airflow signal, and the flow-volume loop was reconstructed for each breathing cycle by plotting the instantaneous flow and the tidal volume. The instantaneous inspiratory and expiratory flows were measured at a 50 % of the respective (inspiratory or expiratory) portion of the tidal volume, and a breath-by-breath analysis of the mid tidal volume flow ratio (I/E ratio) was obtained. There was a positive significant relationship between I/E ratio and VImax (maximal inspiratory volume) for flow-limited breathing (correlation coefficient range: 0.25-0.54). With a lower limit of the normal I/E ratio threshold of 0.97, the sensitivity and specificity of the method were both 76 %. Patients having a I/E ratio lower than 0.97 to 1 are classified as suffering IFL. Therefore, the present invention relates to the above-described non-invasive method which is applicable in the evaluation IFL and to an apparatus measuring I/E ratio and correcting IFL.

Abstract translation: 吸入流量限制（IFL）涉及睡眠相关呼吸障碍的病理生理学。 由于流动限制循环的定义是基于流动和呼吸作用之间的解离，因此识别IFL需要上呼吸道或胸腔内压力测量。 我们检查了在识别IFL时潮气呼吸的流量回路分析的可行性和准确性。 通过整合瞬时气流信号获得潮气量，并通过绘制瞬时流量和潮气量来为每个呼吸循环重建流量循环。 在潮气量的相应（吸气或呼气）部分的50％处测量瞬时吸气和呼气流量，并获得中等潮气量流量比（I / E比）的呼吸分析。 流量限制呼吸（相关系数范围：0.25-0.54）的I / E比与VImax（最大吸气体积）之间存在正相关关系。 正常I / E比阈值下限为0.97，方法灵敏度和特异度均为76％。 I / E比低于0.97比1的患者被归类为患有IFL。 因此，本发明涉及可用于评估IFL的上述非侵入性方法以及测量I / E比率和校正IFL的装置。

公开(公告)号：EP0752828A1

公开(公告)日：1997-01-15

申请号：EP95913833.0

申请日：1995-03-31

Applicant: UNIVERSITE LAVAL

Inventor： SERIES, Frederic ,  MARC, Isabelle

IPC: A61B5 ,  G06F17

CPC classification number: A61B5/083 ,  A61B5/7242 ,  A61B5/7264

Abstract: Inspiratory flow limitation (IFL) is involved in the pathophysiology of sleep-related breathing disorders. Since the definition of flow-limited cycle is based on a dissociation between flow and respiratory efforts, identification of IFL requires upper airway or intrathoracic pressure measurements. We examined the feasability and accuracy of the analysis of the flow-volume loop of a tidal breath in identifying IFL. The tidal volume was obtained by integration of the instantaneous airflow signal, and the flow-volume loop was reconstructed for each breathing cycle by plotting the instantaneous flow and the tidal volume. The instantaneous inspiratory and expiratory flows were measured at a 50 % of the respective (inspiratory or expiratory) portion of the tidal volume, and a breath-by-breath analysis of the mid tidal volume flow ratio (I/E ratio) was obtained. There was a positive significant relationship between I/E ratio and VImax (maximal inspiratory volume) for flow-limited breathing (correlation coefficient range: 0.25-0.54). With a lower limit of the normal I/E ratio threshold of 0.97, the sensitivity and specificity of the method were both 76 %. Patients having a I/E ratio lower than 0.97 to 1 are classified as suffering IFL. Therefore, the present invention relates to the above-described non-invasive method which is applicable in the evaluation IFL and to an apparatus measuring I/E ratio and correcting IFL.