• Respiratory medicine · Dec 2013

    Comparative Study

    A symptom-limited incremental step test determines maximum physiological responses in patients with chronic obstructive pulmonary disease.

    • Simone Dal Corso, Anderson Alves de Camargo, Meyer Izbicki, Carla Malaguti, and Luiz Eduardo Nery.
    • Post-Graduate Program in Rehabilitation Sciences, Universidade Nove de Julho - UNINOVE, Rua Vergueiro 235/249 - 2o subsolo, 01504-001 São Paulo, Brazil. Electronic address: simonedc@uninove.br.
    • Respir Med. 2013 Dec 1;107(12):1993-9.

    BackgroundStep tests have been used to evaluate exercise tolerance and effort-related hypoxemia in different diseases. A symptom-limited incremental step test (IST) has never been tested in COPD patients.AimTo compare maximal physiological responses between an IST and cardiopulmonary exercise testing (CPET), to test the reproducibility of the IST on different days, and to provide a predict equation to estimate VO2 from the IST in patients with COPD.Material And MethodsAt the same day, thirty-four patients (VEF1 46 ± 14% of pred) underwent a CPET on cycle ergometer and the first IST (IST-1) (1 h apart). After 2-5 days, patients repeated the IST (IST-2). Pulmonary gas exchange was measured during all tests.ResultsPeak VO2 was significantly higher in IST-1 and IST-2 than in CEPT (Mean ± SD: 1.19 ± 0.39 L, 1.20 ± 0.40 L, 1.07 ± 0.35 L) with no difference for ventilation (VE), heart rate (HR), and perception of effort. ISTs were highly reproducible, with significant intraclass correlation coefficient (CCI [95% confidence interval]) for number of steps (0.98[0.95-0.99]), VO2 (0.99 [0.98-0.99]), VE (0.97[0.93-0.99]), HR (0.92[0.81-0.97]), and SpO2 (0.96[0.90-0.98]). Desaturation was significantly higher for IST-1 and IST-2 compared with cycling (Mean ± SD: -6 ± 5%, -6 ± 4%, -3 ± 3%). Number of steps and patient weight explained 81% of the variance in peak VO2 (p < 0.001).ConclusionA symptom-limited incremental step test, externally paced, elicits maximal cardiopulmonary and metabolic responses, and is well tolerated and reproducible in patients with COPD.Copyright © 2013 Elsevier Ltd. All rights reserved.

      Pubmed     Free full text   Copy Citation     Plaintext  

      Add institutional full text...

    Notes

     
    Knowledge, pearl, summary or comment to share?
    300 characters remaining
    help        
    You can also include formatting, links, images and footnotes in your notes
    • Simple formatting can be added to notes, such as *italics*, _underline_ or **bold**.
    • Superscript can be denoted by <sup>text</sup> and subscript <sub>text</sub>.
    • Numbered or bulleted lists can be created using either numbered lines 1. 2. 3., hyphens - or asterisks *.
    • Links can be included with: [my link to pubmed](http://pubmed.com)
    • Images can be included with: ![alt text](https://bestmedicaljournal.com/study_graph.jpg "Image Title Text")
    • For footnotes use [^1](This is a footnote.) inline.
    • Or use an inline reference [^1] to refer to a longer footnote elseweher in the document [^1]: This is a long footnote..

    hide…