Journal of Applied Physiology, Vol 77, Issue 2 767-773, Copyright © 1994 by American Physiological Society
Effect of hyperoxia at 1 and 2 ATA on hypoxia and hypercapnia in human skin during experimental inflammation
N. C. Abbot, J. S. Beck, F. M. Carnochan, J. H. Gibbs, D. K. Harrison, P. B. James and J. G. Lowe
Pathology Department, University of Dundee, United Kingdom.
Transcutaneous PO2 and PCO2 measurements and estimates of skin respiration
were monitored at different levels of inspired PO2 in 20 healthy adults
during the first 4 days of the tuberculin reaction, a convenient model of
acute inflammation. Hyperoxia at 1 and 2 ATA significantly increased
transcutaneous PO2 levels in undisturbed and in inflamed skin but did not
fully correct the relative hypoxia at the site of inflammation. Hypercapnia
was reduced with O2 breathing at 2 ATA. The apparent rate of O2 consumption
at the reaction site was raised during hyperoxia, most prominently at 2
ATA. The most intense reactions showed a central relative slowing of
laser-Doppler blood flow indicative of microcirculatory impairment. The
extent of the relative hypoxia and hypercapnia was greatest in these
strongest reactions. The density of lymphocytes and monocytes in biopsies
of 48-h reactions was loosely related to the corresponding transcutaneous
PO2 measurements. The present study provides evidence that diffusion
barriers, in addition to increased local respiration, can contribute to the
apparent hypoxia and hypercapnia of this inflammatory model.
