Effects of oleic acid-induced lung injury on oxygen transport and aerobic capacity

We tested the hypothesis that oleic-acid (OA) infusion impairs gas exchange, decreases total cardiopulmonary O2 delivery and lowers maximal aerobic capacity (V˙O2max). We infused 0.05 ml OA kg−1 (∼3 ml) and ∼563 ml saline into the right atria of four goats [59.1 ± 14.0 (SD) kg] prior to running them on a treadmill at V˙O2max 2-h and 1-d following OA-induced acute lung injury, and with no lung injury. Acute lung injury decreased V˙O2max, O2 delivery, arterial O2 concentration and arterial O2 partial pressure compared to no lung injury. The V˙O2max positively correlated with O2 delivery and inversely correlated with alveolar-arterial O2 partial pressure difference, suggesting that impaired pulmonary gas exchange decreased O2 delivery and uptake. Results indicate OA infusion may be a useful model for acutely impairing pulmonary gas exchange for exercise studies. Seven OA infusions induced smaller chronic gas exchange and arterial O2 partial pressure changes than acute infusion.