Changes in Pulmonary Blood Flow Distribution Following Hyperoxia in ATS Stage 1 to 3 COPD Patients

Abstract

PURPOSE: We have shown that lung blood flow pulmonary transit time distribution (PTTD) in stage 1 COPD patients (ATS) fits three distinct patterns (patterns A, B, C), depending on the response to hyperoxic challenge. Pattern A distribution is normal and unchanged during hyperoxia, pattern B distribution is significantly enlarged but remains unchanged during hyperoxia, pattern C distribution is enlarged as in pattern B but returns to normal during hyperoxia (Am J Respir Crit Care Med 2002; 165, 8, part 2, A 654).