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Development of a methacholine challenge method to minimize methacholine waste


, : Development of a methacholine challenge method to minimize methacholine waste. Chest 124(4): 1522-1525

Background: The standard 2-min tidal breathing methacholine challenge utilizes 3 mL to produce an output of 0.26 mL per 2 min, resulting in a substantial amount of methacholine being discarded. Objective: To develop a method with reduced methacholine waste and to compare it to the standard method. Methods: Twelve subjects with mild, well-controlled asthma volunteered for this investigation. They underwent three methacholine challenges in random order. The first challenge was the conventional 2-min tidal breathing method using 3 mL of doubling concentrations inhaled for 2 min at 5-min intervals. The first modification utilized 1.5 mL of quadrupling concentrations inhaled for 1 min and then 2 min, keeping the time interval constant at 3 min between completion of one inhalation and commencement of the next inhalation. The second modification utilized 1.5 mL of eightfold concentration step-ups inhaled for 30 s, 60 s, and 120 s with a time interval of 3 min between completion of one inhalation and commencement of the next inhalation. For each method, the provocative concentration of methacholine causing a 20% fall in FEV1 (PC20) was calculated based on a 2-min equivalent-dose inhalation. Results: There was no significant difference in the geometric mean PC20 (1.5 mg/mL, 1.6 mg/mL, and 1.6 mg/mL for the three methods, respectively; p=0.47). The quadrupling concentration method was preferred because it was less subject to error than the other modification. Conclusion: The amount of methacholine discarded during a methacholine challenge can be reduced by two thirds by decreasing the volume from 3 to 1.5 mL, and by using quadrupling concentrations inhaled either with quadrupling-dose step-ups, or with doubling-dose step-ups by using sequential 1-min and 2-min inhalations.

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Accession: 011944519

PMID: 14555588

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Doar William R.; Hudson Erin E., 2007: Observed human and natural changes on coastal lands and shorelines. The physical changes, incurred since the last coastal lands and shorelines baseline, become a part of any new coastal geological map or update to an existing map. Geological mapping along the southern coast of South Carolina has identified both na...

Saitoh, Takashi; Ikeue, Takahisa; Ohgo, Yoshiki; Nakamura, Mikio, 1997: Barriers to rotation of axially coordinated imidazole ligands in nonplanar meso-tetraalkylporphyrinato-cobalt(III) complexes. Dynamic NMR study of a series of meso-(Co(TRP)(L)-2)Cl, where R is an alkyl group and L is a substituted imidazole, has been carried out. While the complexes with unhindered imidazole show no splitting of the signals, those with bulky imidazoles e...

Slanina, L; Sokol, J., 1971: Colentrin and Colentrin S--preparations against coli-enteritis in swine and piglets used for oral administration. Veterinarstvi 1 (8) 371-375

Biadun, W.; Krasnodebski, S., 2007: Occurrence of the common tick Ixodes ricinus in environments of various degrees and characteristics of anthropogenic impact. The occurrence and relative numbers of common tick Ixodes ricinus in 3 forest complexes (Gulowskie Forests, Kozlowiekie Forest, Dabrowa Forest) in Lublin, Poland were determined. Flagging was the method used during the peak activity of ticks in th...

Guzman, H.; TM., 1967: Contribucion al estudio de las aves de Chile (clave para las especies de Valparaiso coe exclusion de Passeriformes). Boln Cienc biol Chile, 1: 47-71

Remy, P. A., 1954: Pauropodes de la zone du canal de Panama. Revue Francaise d'Entomologie, 21: 291-298

Mandy, Gy.; Kovacs, S.; Mesch, J., 1963: Data on the ecology of Hungarian wheats. III. The climatic ecology of Hungarian and intensive foreign wheats. Data are provided on the dates of heading, flowering and wax ripeness of Hungarian and high-yielding foreign winter wheats each sown on six successive dates, together with figures showing the individual amplitude for each of these characters; diff...

Lepran I.; Lefer A.M., 1985: Preservation of ischemic myocardium by propyl gallate a lipoxygenase inhibitor. Federation Proceedings 44(5): 1479

Gini, Francesca; Del Moro, Federica; Macchia, Franco; Pineschi, Mauro, 2003: Regio- and enantioselective copper-catalyzed addition of dialkylzinc reagents to cyclic 2-alkenyl aziridines. The reactions of some organocopper reagents with cyclic 2-alkenyl aziridines were examined. The stereoselectivity of the addition reaction of dialkylzinc can be strongly influenced by the use of phosphoramidites as ligands for copper. Chiral coppe...

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