Estudio de la difusión pulmonar durante el ejercicio en condiciones extremas

Resumen

Lung diffusing capacity describes the alveolar-capillary diffusion in the lungs, which increase linearly in relation to cardiac output, and decrease in the presence of lung interstitial disease. It changes due to exercise or high-altitude exposure, either increasing due to alveolar capillary recruitment and distension, or decreasing due to interstitial fluid accumulation. This thesis aimed to study whether aquatic athletes (swimmers and artistic swimmers) had a decrease in lung diffusing capacity for carbon monoxide (DLCO) during swimming training, and whether altitude training camp or an acute exposure to exercise at high-altitude provoke changes in DLCO. The first article describes the justification of this thesis. In this report case, we describe the case of a female swimmers who shows dyspnoea related to the intensity of the swimming exercise associated with a lower spirometric values post-exercise and the presence of ultrasound lung comets (ULCs) suggesting a swimming-induced pulmonary oedema (SIPO). The report case conclude with the administration of an inhibitor of the carbonic anhydrase (Acetazolamide) to solve this condition. The second, third, and forth article describe the changes in DLCO during swimming training in elite swimmers and artistic swimmers in a pre- vs. post-training comparison. We show a slight decrease in lung diffusing capacity (−2.5 and 4.0%), showing that swimmers experience subclinical decrease in lung diffusing capacity after training. Also, there were a large inter-individual variability in the response of DLCO to swim training along the follow-up including 11 out of 32 subjects showing a considerable average decrease (−5.6–20%), suggesting that, doctors and coaches should pay attention to the individual changes in alveolar-capillary diffusing capacity among elite swimmers. The fifth article studies the possible modifications in lung diffusing capacity during a 14-day swimming altitude training camp at 1,850 m. There were no changes in DLCO after the altitude training camp, but a decrease in alveolar volume (VA) and an increase in transfer coefficient of the lung for carbon monoxide (KCO) occur. In contrast to the results found at sea level, an acute swimming training session in moderate altitude does not change lung diffusing capacity, but a posterior cycling session at normobaric-simulated 3,000 m reduced DLCO (−10%). The sixth and seventh article reports the lung diffusing response to 30-min moderate intensity interval exercise in a short-term exposure to high-altitude (4,000 m) in elite swimmers and control subjects. There were no changes in DLCO after exercise although elite swimmers showed a larger decrease in SpO2 (72 ± 5 %) and a lower increase in HR (139 ± 9 beats·min-1) compared to control subjects.