Pulmonary Diseases, Radboud University Medical Centre, Nijmegen, The Netherlands,
Pulmonary Diseases, Admiraal de Ruyter Ziekenhuis, Goes, The Netherlands.
Respiration. 2019;97(6):569-575. doi: 10.1159/000496290. Epub 2019 Mar 14.
A simple technique to measure dynamic hyperinflation (DH) in patients with chronic obstructive pulmonary disease (COPD) is the metronome-paced tachypnea test (MPT). Earlier studies show conflicting results about the accuracy of the MPT compared to cardiopulmonary exercise testing (CPET).
The focus was to investigate the diagnostic accuracy of MPT to detect DH in a prospective and clinical study.
COPD patients were included; all underwent spirometry, CPET, and MPT. DH (ΔIC) was calculated as the difference in % between inspiratory capacity (IC) at the start and end of the test divided by IC at the start. A subject was identified as a hyperinflator, if ΔIC (% of ICrest) was smaller than -10.2 and -11.1% in CPET and MPT, respectively. With these values, sensitivity and specificity were calculated. Bland-Altman plots were made of ΔIC (% of ICrest).
In the prospective and clinical study, 107 and 48 patients were included, respectively. Sensitivity of the MPT was 85% in both studies. The specificities were 33 and 27%, respectively. In the prospective study, B = +2.6%, L = 30.6, and -25.6%. In the clinical study, B = +0.8%, L = 31.0, and -29.1%.
MPT seems to be a good replacement for CPET in group studies. The mean amount of DH was not different between CPET and MPT. On an individual level, MPT cannot be used to identify hyperinflators; it should be kept in mind that MPT overdiagnoses DH. The amount of DH should not be interchanged between CPET and MPT.
一种测量慢性阻塞性肺疾病（COPD）患者动态过度充气（DH）的简单技术是节拍器-paced 呼吸急促试验（MPT）。早期研究表明，与心肺运动测试（CPET）相比，MPT 的准确性存在相互矛盾的结果。
本研究旨在通过前瞻性临床研究探讨 MPT 检测 DH 的诊断准确性。
纳入 COPD 患者；所有患者均接受了肺量计检查、CPET 和 MPT。DH（ΔIC）的计算方法为测试开始和结束时吸气量（IC）的差异与测试开始时 IC 的百分比。如果 CPET 和 MPT 中ΔIC（ICrest 的百分比）分别小于-10.2%和-11.1%，则认为患者为过度充气者。使用这些值计算了敏感性和特异性。制作了 ΔIC（ICrest 的百分比）的 Bland-Altman 图。
在这项前瞻性临床研究中，分别纳入了 107 例和 48 例患者。在两项研究中，MPT 的敏感性均为 85%。特异性分别为 33%和 27%。在前瞻性研究中，B = +2.6%，L = 30.6，-25.6%。在临床研究中，B = +0.8%，L = 31.0，-29.1%。
MPT 似乎可以替代 CPET 用于组研究。CPET 和 MPT 之间 DH 的平均量没有差异。在个体水平上，MPT 不能用于识别过度充气者；应该记住，MPT 过度诊断 DH。CPET 和 MPT 之间不应互换 DH 的量。
