Linked Life Data

3516038

Source:http://linkedlifedata.com/resource/pubmed/id/3516038

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1986-5-1
pubmed:abstractText
The dosimeter method of administering doubling cumulative doses of methacholine to measure bronchial responsiveness was standardized to control for the effects of a number of potential influencing variables. The aerodynamic mass median diameter of the challenge aerosol produced from a DeVilbiss 646 nebulizer proved to be 1.2 mu, and the mean output per inhalation 8.9 microliters. Each challenge dose comprised 5 inhalations. Cumulative doses ranged from 0.3 methacholine inhalation units (1 unit = 1 inhalation of aerosol from a 1-mg/ml solution of methacholine, i.e., 8.9 micrograms methacholine) to a possible 640 units, the maximum that was considered reasonable to avoid the risk of unacceptable systemic effects. Responsiveness was expressed as the dose provoking a 20% decline (PD20) in FEV1. Modifications in this full protocol were introduced to facilitate epidemiologic investigations. Physician assessments coupled with baseline measurements of ventilatory function allowed starting at higher dosages for persons with low probability of hyperresponsiveness, thereby shortening the time required for testing to an average of 38 min. In a validation study of 20 persons using both the full and modified protocols, no significant differences were detected between measured PD20 values (geometric means Full versus Modified, 14.83 versus 14.88; r = 0.99). The modified protocol was used to measure bronchial responsiveness in 254 workers exposed to toluene diisocyanate. It proved to be safe and acceptable. Sixty-four workers (25.2%) were found to be reactors. The frequency distribution of the PD20 values exhibited a steadily increasing trend, consistent with a unimodal distribution.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0003-0805
pubmed:author
pubmed:issnType
Print
pubmed:volume
133
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
600-4
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
Modification of the methacholine inhalation test and its epidemiologic use in polyurethane workers.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't