Hyperoxia increases arterial oxygen pressure during exercise in type 2 diabetes patients: a feasibility study

OBJECTIVE The study investigated the feasibility and potential outcome measures during acute hyperoxia in type 2 diabetes patients (DM2). METHODS Eleven DM2 patients (7 men and 4 women) were included in the study. The patients cycled (30 min at 20% Wmax) whilst breathing three different supplemental oxygen flows (SOF, 5, 10, 15 L min(-1)). During hyperoxic exercise, arterial blood gases and intra-arterial blood pressure measurements were obtained. RESULTS Arterial pO2 levels increased significantly (ANOVA, p < 0.05) with SOF: 13.9 ± 1.2 (0 L min(-1)); 18.5 ± 1.5 (5 L min(-1)); 21.7 ± 1.7 (10 L min(-1)); 24.0 ± 2.3 (15 L min(-1)). Heart rate (HR) and pH increased significantly after terminating administration of hyperoxic air. CONCLUSIONS An SOF of 15 L min(-1) appears to be more effective than 5 or 10 L min(-1). Moreover, HR, blood pressure, blood lactate and pH are not recommended as primary outcome measures.