Balfe David L, Lewis Michael, Mohsenifar Zab
Division of Pulmonary/Critical Care Medicine, Department of Medicine, Cedars-Sinai Medical Center, Room 6732, UCLA School of Medicine, 8700 Beverly Boulevard, Los Angeles, CA 90048,
Chest. 2002 Oct;122(4):1365-9. doi: 10.1378/chest.122.4.1365.
No recommendation currently exists for grading the severity of airway obstruction in the presence of additional restriction. The grading of airway obstruction is currently based on the FEV(1) (American Thoracic Society [ATS] recommendations), while prior recommendations by the Intermountain Thoracic Society (ITS) graded the severity of obstruction based on the FEV(1)/FVC ratio. The objective was to compare the grading of airway obstruction using the percent predicted FEV(1) (ATS) with a confidence interval-based system (ITS), with particular focus on pulmonary functions in patients having both airway obstructions and restrictions.
Retrospective analysis.
Tertiary medical center.
A retrospective analysis of 21,499 patient pulmonary function tests (PFTs) was performed. The predicted values of Crapo and coworkers were used.
The distribution of the severity of the obstruction was compared using the ATS and ITS methods for PFTs with normal, increased, or decreased total lung capacity (TLC). Analysis was performed using the chi(2) method. Of the 21,499 PFTs that were analyzed, TLC was measured in 28% (5,962 PFTs). In this cohort, 44% (2,619 PFTs) gave evidence of obstruction. Of these, 147 PFTs demonstrated additional restriction. While the ATS criteria graded 133 of these PFTs (90%) as being severe, the ITS criteria graded only 4 PFTs (3%) as severe (the severity distribution between the methods was significantly different [p < 0.01]).
In view of the possible overestimation of the severity of obstruction in PFTs with concurrent restriction using the percentage of predicted FEV(1) values, consideration should be given to grading the severity of obstruction on the basis of the FEV(1)/FVC ratio in this specific subset of PFTs.
目前尚无针对存在额外限制时气道阻塞严重程度分级的推荐。目前气道阻塞的分级基于第一秒用力呼气容积（FEV₁）（美国胸科学会[ATS]的推荐），而山间胸科学会（ITS）先前的推荐是基于FEV₁/用力肺活量（FVC）比值对阻塞严重程度进行分级。目的是比较使用预测FEV₁百分比（ATS）与基于置信区间的系统（ITS）对气道阻塞的分级，特别关注同时存在气道阻塞和限制的患者的肺功能。
回顾性分析。
三级医疗中心。
对21499例患者的肺功能测试（PFT）进行了回顾性分析。使用了克拉波及其同事的预测值。
使用ATS和ITS方法比较了总肺容量（TLC）正常、增加或减少的PFT中阻塞严重程度的分布。采用卡方检验进行分析。在分析的21499例PFT中，28%（5962例PFT）测量了TLC。在该队列中，44%（2619例PFT）有阻塞证据。其中，147例PFT显示有额外限制。虽然ATS标准将这些PFT中的133例（90%）评为重度，但ITS标准仅将4例PFT（3%）评为重度（两种方法之间的严重程度分布有显著差异[p<0.01]）。
鉴于使用预测FEV₁值百分比对同时存在限制的PFT中阻塞严重程度可能存在高估，对于这一特定子集的PFT，应考虑基于FEV₁/FVC比值对阻塞严重程度进行分级。
