Biomaterial Database

Effect of methacholine induced bronchoconstriction on the spectral characteristics of breath sounds in asthma. 1992

D P Spence, and S Bentley, and D H Evans, and M D Morgan

Department of Respiratory Medicine, Glenfield General Hospital, Leicester.

BACKGROUND Analysis of breath sounds by digital techniques offers an attractive non-invasive method of monitoring changes in airway calibre. Asthmatic breath sounds have been analysed and related to changes in forced expiratory volume in one second (FEV1). METHODS Bronchoconstriction was induced with methacholine in six asthmatic subjects on two occasions and changes in FEV1 and breath sound spectra were measured. RESULTS Audible wheeze appeared after a mean (SE) fall in FEV1 of 35% (6.3%) but the level was not reproducible within patients. The mean and median frequency of the spectra of breath sounds correlated with the percentage of predicted FEV1 (r = -0.5 and -0.6 respectively; p < 0.001). Inclusion of the quartile frequencies in a stepwise multiple regression reduced the residual variance by a further 9%. CONCLUSIONS Detecting changes in airway calibre by this method of sound analysis so far produces qualitative data only and will not yield quantitative data in individual patients.

UI	MeSH Term	Description	Entries
D012135	Respiratory Sounds	Noises, normal and abnormal, heard on auscultation over any part of the RESPIRATORY TRACT.	Breathing Sounds,Crackles,Lung Sounds,Pleural Rub,Rales,Rhonchi,Stridor,Wheezing,Breathing Sound,Crackle,Lung Sound,Pleural Rubs,Rale,Respiratory Sound,Rhonchus,Rub, Pleural,Sound, Breathing,Sound, Lung,Sound, Respiratory,Sounds, Breathing,Sounds, Lung,Stridors,Wheezings
D001985	Bronchial Provocation Tests	Tests involving inhalation of allergens (nebulized or in dust form), nebulized pharmacologically active solutions (e.g., histamine, methacholine), or control solutions, followed by assessment of respiratory function. These tests are used in the diagnosis of asthma.	Allergen Bronchial Provocation Tests,Allergen Challenge, Endobronchial,Antigen Bronchial Provocation Tests,Bronchial Allergen Challenge,Bronchial Challenge Tests,Inhalation Provocation Tests,Provocation Tests, Bronchial,Endobronchial Challenge Tests,Allergen Challenge, Bronchial,Allergen Challenges, Bronchial,Allergen Challenges, Endobronchial,Bronchial Allergen Challenges,Bronchial Challenge Test,Bronchial Provocation Test,Challenge Test, Bronchial,Challenge Test, Endobronchial,Challenge Tests, Bronchial,Challenge Tests, Endobronchial,Challenge, Bronchial Allergen,Challenge, Endobronchial Allergen,Challenges, Bronchial Allergen,Challenges, Endobronchial Allergen,Endobronchial Allergen Challenge,Endobronchial Allergen Challenges,Endobronchial Challenge Test,Inhalation Provocation Test,Provocation Test, Bronchial,Provocation Test, Inhalation,Provocation Tests, Inhalation,Test, Bronchial Challenge,Test, Bronchial Provocation,Test, Endobronchial Challenge,Test, Inhalation Provocation,Tests, Bronchial Challenge,Tests, Bronchial Provocation,Tests, Endobronchial Challenge,Tests, Inhalation Provocation
D005541	Forced Expiratory Volume	Measure of the maximum amount of air that can be expelled in a given number of seconds during a FORCED VITAL CAPACITY determination . It is usually given as FEV followed by a subscript indicating the number of seconds over which the measurement is made, although it is sometimes given as a percentage of forced vital capacity.	Forced Vital Capacity, Timed,Timed Vital Capacity,Vital Capacity, Timed,FEVt,Capacities, Timed Vital,Capacity, Timed Vital,Expiratory Volume, Forced,Expiratory Volumes, Forced,Forced Expiratory Volumes,Timed Vital Capacities,Vital Capacities, Timed,Volume, Forced Expiratory,Volumes, Forced Expiratory
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D001249	Asthma	A form of bronchial disorder with three distinct components: airway hyper-responsiveness (RESPIRATORY HYPERSENSITIVITY), airway INFLAMMATION, and intermittent AIRWAY OBSTRUCTION. It is characterized by spasmodic contraction of airway smooth muscle, WHEEZING, and dyspnea (DYSPNEA, PAROXYSMAL).	Asthma, Bronchial,Bronchial Asthma,Asthmas
D015203	Reproducibility of Results	The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.	Reliability and Validity,Reliability of Result,Reproducibility Of Result,Reproducibility of Finding,Validity of Result,Validity of Results,Face Validity,Reliability (Epidemiology),Reliability of Results,Reproducibility of Findings,Test-Retest Reliability,Validity (Epidemiology),Finding Reproducibilities,Finding Reproducibility,Of Result, Reproducibility,Of Results, Reproducibility,Reliabilities, Test-Retest,Reliability, Test-Retest,Result Reliabilities,Result Reliability,Result Validities,Result Validity,Result, Reproducibility Of,Results, Reproducibility Of,Test Retest Reliability,Validity and Reliability,Validity, Face
D016084	Bronchoconstriction	Narrowing of the caliber of the BRONCHI, physiologically or as a result of pharmacological intervention.	Bronchial Constriction,Bronchial Constrictions,Bronchoconstrictions,Constriction, Bronchial,Constrictions, Bronchial
D016210	Methacholine Chloride	A quaternary ammonium parasympathomimetic agent with the muscarinic actions of ACETYLCHOLINE. It is hydrolyzed by ACETYLCHOLINESTERASE at a considerably slower rate than ACETYLCHOLINE and is more resistant to hydrolysis by nonspecific CHOLINESTERASES so that its actions are more prolonged. It is used as a parasympathomimetic bronchoconstrictor agent and as a diagnostic aid for bronchial asthma. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1116)	Methacholine,2-(Acetyloxy)-N,N,N-trimethyl-1-propanaminium Chloride,Acetyl-2-methylcholine Chloride,Acetyl-beta-methacholine Chloride,Acetyl-beta-methylcholine,Mecholine,Mecholyl,Provocholine,Provokit,Acetyl 2 methylcholine Chloride,Acetyl beta methacholine Chloride,Acetyl beta methylcholine,Chloride, Methacholine