HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 29/2/330    most recent 09031936.00094006v1 Alert me when this article is cited Alert me if a correction is posted Permissions Request Permissions Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (4) Citing Articles via Google Scholar Google Scholar Articles by Dal Corso, S. Articles by Nery, L. E. Search for Related Content PubMed PubMed Citation Articles by Dal Corso, S. Articles by Nery, L. E.

A step test to assess exercise-related oxygen desaturation in interstitial lung disease

Pulmonary Function and Clinical Exercise Physiology Unit (SEFICE), Division of Respiratory Diseases, Federal University of São Paulo (UNIFESP), São Paulo, Brazil.

CORRESPONDENCE: J. A. Neder, Respiratory Division, Dept of Medicine, Federal University of São Paulo, Paulista School of Medicine (UNIFESP-EPM), Rua Francisco de Castro 54, Vila Clementino, CEP 04020-050 São Paulo Brazil. Fax: 55 1155752843. E-mail: albneder{at}pneumo.epm.br

Keywords: Exercise induced, exercise tests, interstitial lung diseases, oxygen saturation, oxygen uptake, pulmonary dysfunction

Received: July 17, 2006
Accepted September 18, 2006

A 6-min step test (6MST) may constitute a practical method for routinely assessing effort tolerance and exercise-related oxyhaemoglobin desaturation (ERD) in the primary care of patients with interstitial lung disease.

In total, 31 patients (19 males) with idiopathic pulmonary fibrosis (n = 25) and chronic hypersensitivity pneumonia were submitted, on different days, to two 6MSTs. Physiological responses were compared with those found on maximal and submaximal cycle ergometer tests at the same oxygen uptake (V'_O2). Chronic breathlessness was also determined, as measured by the baseline dyspnoea index (BDI).

Responses to 6MST were highly reproducible: 1.3±2.0 steps·min^-1, ±5 beats·min^-1 (cardiac frequency), ±50 mL·min^-1 (V'_O2), ±7 L·min^-1 (minute ventilation) and ±2% (arterial oxygen saturation measured by pulse oximetry (S_p,O2)). The number of steps climbed in 6 min was correlated to peak V'_O2 and the BDI. There were significant associations among the tests in relation to presence (change in S_p,O2 between rest and exercise 4%) and severity (S_p,O2 <88%) of ERD. Four patients, however, presented ERD only in response to 6MST. Resting diffusing capacity of the lung for carbon monoxide and alveolar–arterial oxygen tension difference were the independent predictors of the number of steps climbed.

A single-stage, self-paced 6-min step test provided reliable and reproducible estimates of exercise capacity and exercise-related oxyhaemoglobin desaturation in interstitial lung disease patients.

This article has been cited by other articles:

				J. P. Lynch III Idiopathic Pulmonary Fibrosis, Nonspecific Interstitial Pneumonia/Fibrosis, and Sarcoidosis ACCP Pulmonary Med Brd Rev, January 1, 2009; 25(0): 635 - 686. [Full Text] [PDF]

				G. Giannakoulas, T. D. Karamitsos, G. Pitsiou, and H. I. Karvounis Right ventricular dysfunction and functional limitation in idiopathic pulmonary fibrosis Eur. Respir. J., January 1, 2008; 31(1): 219 - 220. [Full Text] [PDF]

				J. A. Neder From the authors Eur. Respir. J., January 1, 2008; 31(1): 220 - 221. [Full Text] [PDF]