Faculdade de Medicina, Universidade Regional de Joinville, Joinville, SC, Brasil.
J Bras Pneumol. 2010 Jul-Aug;36(4):460-7. doi: 10.1590/s1806-37132010000400011.
To use clinical and spirometry findings in order to distinguish between the restrictive and nonspecific patterns of pulmonary function test results in patients with low FVC and a normal or elevated FEV1/FVC ratio.
We analyzed the pulmonary function test results of 211 adult patients submitted to spirometry and lung volume measurements. We used the clinical diagnosis at the time spirometry was ordered, together with various functional data, in order to distinguish between patients presenting with a "true" restrictive pattern (reduced TLC) and those presenting with a nonspecific pattern (normal TLC).
In the study sample, TLC was reduced in 144 cases and was within the normal range in 67. The most common causes of a nonspecific pattern were obstructive disorders, congestive heart failure, obesity, bronchiolitis, interstitial diseases, and neuromuscular disorders. In patients given a working diagnosis of pulmonary fibrosis, pleural disease, or chest wall disease, the positive predictive value (PPV) for restriction was >or= 90%. In males, an FVC <or= 60% of predicted had a PPV for restriction of 98.8%. In females, the restrictive pattern was found in 84.4% of those with an FVC <or= 50% of predicted. A difference of >or= 0% between the FEV1% and the FVC% had a PPV for restriction of 89.5%. After performing logistic regression, we developed a point scale for predicting the restrictive pattern.
In many patients with reduced FEV1, reduced FVC, and a normal FEV1/FVC ratio, the restrictive pattern can be identified with confidence through the use of an algorithm that takes the clinical diagnosis and certain spirometry measurements into account.
利用临床和肺量计检查结果，鉴别 FVC 降低而 FEV1/FVC 比值正常或增高患者的限制性和非特异性肺功能测试结果模式。
我们分析了 211 例接受肺量计和肺容积测量的成年患者的肺功能测试结果。我们将进行肺量计检查时的临床诊断与各种功能数据结合起来，用于鉴别表现为“真性”限制性模式（TLC 降低）和非特异性模式（TLC 正常）的患者。
在研究样本中，TLC 降低见于 144 例，TLC 正常见于 67 例。非特异性模式最常见的原因是阻塞性疾病、充血性心力衰竭、肥胖、细支气管炎、间质性疾病和神经肌肉疾病。在被诊断为肺纤维化、胸膜疾病或胸壁疾病的患者中，限制的阳性预测值（PPV）≥90%。在男性中，FVC＜60%预计值时限制的 PPV 为 98.8%。在女性中，FVC＜50%预计值时，84.4%的患者表现为限制性模式。FEV1%和 FVC%之间的差值＞0%时限制的 PPV 为 89.5%。进行逻辑回归后，我们开发了一种用于预测限制性模式的点评分。
在许多 FEV1 降低、FVC 降低而 FEV1/FVC 比值正常的患者中，可以通过考虑临床诊断和某些肺量计检查结果的算法，有信心地识别出限制性模式。
