Effect of acute metabolic acid/base shifts on the human airway calibre

Citation
F. Brijker et al., Effect of acute metabolic acid/base shifts on the human airway calibre, RESP PHYSL, 124(2), 2001, pp. 151-158
Citations number
21
Language
INGLESE
art.tipo
Article
Categorie Soggetti
da verificare
Journal title
RESPIRATION PHYSIOLOGY
ISSN journal
0034-5687 → ACNP
Volume
124
Issue
2
Year of publication
2001
Pages
151 - 158
Database
ISI
SICI code
0034-5687(200101)124:2<151:EOAMAS>2.0.ZU;2-4
Abstract
Acute metabolic alkalosis (NaHCO3), acidosis (NH4Cl), and placebo (NaCl) we re induced in 15 healthy volunteers (12 females, median age 34 (range 24-56 ) years) in a double blind, placebo controlled study to evaluate the presen ce of the effects on airway calibre. Acid-base shifts were determined by ca pillary blood gas sampling. Measurements were performed at the maximal acid -base shift, 90 min after intervention. Airway resistance (R-aw) and specif ic airway conductance (sG(aw)), were evaluated, as primary variables, pre a nd post intervention. Secondary variables, including bronchial responsivene ss to histamine, maximal respiratory mouth pressures and grip strength, wer e evaluated post intervention. In alkalosis, base excess (BE) increased fro m -0.3 (- 3.0-1.9) to 3.0 (1.0-4.8) mmol/l and pH increased from 7.41 (7.37 -7.43) to 7.44 (7.39-7.47) (both P < 0.01), accompanied by an increase in P a-CO2: 4.7 (4.0-5.7) to 5.0 (4.7-6.1) kPa (P < 0.05). R-aw increased from 0 .156 (0.134-0.263) to 0.169 (0.132-0.271) kPa s/L (P < 0.05), sG(aw) decrea sed, but this was not statistically significantly. In acidosis, BE decrease d from -0.2 (-2.0-2.2) to -3.5 ( - 6.3-1.1) mmol/l and pH decreased from 7. 41 (7.39-7.45) to 7.36 (7.31 - 7.40) (both P < 0.01), accompanied by a non- significant decrease in Pa-CO2. Changes in R-aw and sG(aw) were contrary to those in alkalosis, but did not reach statistical significance. Acute meta bolic acid-base shifts mildly influence the airway calibre in healthy human subjects. (C) 2001 Elsevier Science B.V. All rights reserved.