Pulmonary oedema following exercise in humans

• Main Author: Hodges, Alastair Neil Hugh
• Language: English
• Published: 2010
• Online Access: http://hdl.handle.net/2429/18445

In order to determine if transient pulmonary oedema occurs after strenuous exercise, 10 well trained male athletes were challenged in normoxic and hypoxic conditions. To determine the minimal tolerable F₁O₂ for hypoxia, ten aerobically trained male athletes (VC^max = 57.2 ± 7.95mL-kg⁻¹•min⁻¹) performed graded cycling work to maximal effort under four conditions of varying FT02 (21%, 18%, 15%, 12%). Mean VChmax was significantly reduced while breathing 15 and 12% oxygen (VC^max = 48.2 ± 7.9 and 31.5 ± 7.4 mL-kg⁻¹•min⁻¹ respectively). In the 12% oxygen condition, the majority of the subjects were not able to complete maximal exercise without SaO"2 falling below 70%. Ten highly trained males (V02max = 65.0 ± 7.5mL- kg⁻¹•min⁻¹) then underwent assessment of lung density by quantified magnetic resonance imaging prior to and 54.0 ± 17.2 and 100.7 ± 15.1 min following 60 min of cycling exercise (61.6 ± 9.5% VO₂max). The same subjects underwent an identical measure prior to and 55.6 ± 9.8 and 104.3 ± 9.1 min following 60 min cycling exercise (65.4 ± 7.1% hypoxic VChmax) in hypoxia (F₁O₂ = 15.0%). Two subjects demonstrated mild exercise-induced arterial hypoxaemia (EIAH) (minSa0₂ = 94.5 & 93.8%), and 7 demonstrated moderate EIAH (minSa0₂ = 91.4 ± 1.1%) during a preliminary VC^max test in normoxia. No significant differences (p<0.05) were found in lung density following exercise in either condition. Mean lung densities, measured once pre- and twice post-exercise, were 0.177 ± 0.019, 0.181 ± 0.019 and 0.173 ± 0.019g•mL⁻¹ in the normoxic condition, and 0.178 ± 0.021, 0.174 ± 0.022 and 0.176 ± 0.019g•mL⁻¹ in hypoxic condition. These results indicate that transient interstitial pulmonary oedema does not occur following sustained steady-state cycling exercise in normoxia or hypoxia. This diminishes the likelihood of transient oedema as a mechanism for changes in SaO₂ during sustained exercise. === Education, Faculty of === Kinesiology, School of === Graduate