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) 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 ISI 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 ISI Web of Science (9) Citing Articles via Google Scholar Google Scholar Articles by Izbicki, G. Articles by Bar-Yishay, E. Search for Related Content PubMed PubMed Citation Articles by Izbicki, G. Articles by Bar-Yishay, E.

Methacholine inhalation challenge: a shorter, cheaper and safe approach

Institute of Pulmonology, Hadassah University Hospital, Hebrew University-Hadassah Medical School, Jerusalem, Israel

CORRESPONDENCE: E. Bar-Yishay, Institute of Pulmonology, Hadassah University Hospital, Hebrew University-Hadassah Medical School, P.O. Box 12000, Jerusalem, 91120, Israel. Fax: 972 2 6435897

This research was supported by grants from the Israel Lung Association and from the Swiss National Scientific Foundation (No. 81GE-05006), the Swiss Society of Pulmonology and the Freiwillige Akademische Gesellschaft.

Increased nonspecific bronchial hyperresponsiveness to pharmacological agents such as histamine or methacholine (MCh) is a hallmark of asthma. The measurement of airway reactivity is quite sensitive but testing is tedious, and time and money consuming. The present aim was, therefore, to design the shortest possible, yet safe inhalation challenge protocol applicable for a lung function referral centre.

All records of studies performed in our institution during 1996 were analyzed retrospectively with a baseline ratio (bl) of forced expiratory volume in one second/forced vital capacity (FEV₁/FVC) 0.7 (n=449). It was questioned what the initial dose should be, and whether some inhalation steps could have been skipped without losing pertinent information and/or causing an adverse response (a fall in FEV₁ >40%). When unavailable, provocative dose causing a 20% fall in FEV₁ (PD₂₀) values were obtained by linear inter- or extrapolation of the existing data.

The present study showed that three-fold concentration steps could have been employed with minimal change in outcome. Only 15/449 patients (3.3%) would have experienced a severe response. Five subjects (of 169, 3.0%) with FEV₁/FVC_bl 0.7–0.8 reacted to inhalation up to 0.073 µmol. Four subjects (of 280, 1.4%) with FEV₁/FVC_bl0.8 reacted to inhalation up to 0.219 µmol.

The authors suggest that: 1) an initial dose of 0.219 µmol (initial concentration=0.21 mg·mL^–1) may be used when the baseline ratio of forced expiratory volume in one second to forced vital capacity 0.8 and 0.073 µmol (initial concentration=0.07 mg·mL^–1) when the baseline ratio is <0.8; 2) a tripling dose protocol is easier to perform, cheaper and 30.2% faster, yet just as safe; and 3) other abbreviated protocols used in epidemiologic settings may not be applicable in a referral centre setting.

Keywords: abbreviated, bronchial challenge test, methacholine, protocol

This article has been cited by other articles:

				T. C. Fardon, M. R. Hodge, and B. J. Lipworth Evaluation of an Abbreviated Adenosine Monophosphate Bronchial Challenge Chest, June 1, 2005; 127(6): 2222 - 2225. [Abstract] [Full Text] [PDF]

				C. Wubbel, M. J. Asmus, G. Stevens, S. E. Chesrown, and L. Hendeles Methacholine Challenge Testing*: Comparison of the Two American Thoracic Society-Recommended Methods Chest, February 1, 2004; 125(2): 453 - 458. [Abstract] [Full Text] [PDF]

				E. Bar-Yishay, D. W. Cockcroft, D. D. Marciniuk, T. S. Hurst, D. J. Cotton, K. F. Laframboise, B. D. McNab, and R. P. Skomro Abbreviated Methacholine Challenge: How Safe Are Short Procedures? Chest, August 1, 2002; 122(2): 752 - 753. [Full Text] [PDF]