Pulmonary oedema induced by strenuous swimming: a field study

The purpose of the study was to document the incidence and recurrence rate of pulmonary oedema induced by strenuous swimming (SIPO), and to study the changes in relevant physiological parameters. Thirty-five young men were re peatedly examined over a 2-month period after a swimming time trial in the open sea. A tentative diagnosis of SIPO was made when the swimmer reported shortness of breath accompanied by cough. Twenty-nine events of SIPO were d iagnosed in 21 individuals (60% incidence). Oxygen saturation was significa ntly reduced in SIPO. Mean forced vital capacity (FVC) and FEV, were signif icantly lower in the severe SIPO group. Also, mean FVC and mid-expiratory f lows (FEF25-75%) obtained 12 months earlier during screening for the progra mme were lower in individuals who later had SIPO. The ratios of post-swim F VC and FEV1 values to the corresponding selection examination values were l ower in the severe SIPO group. Thus volumes decreased in the SIPO group, be sides being lower at the start. Shortness of breath and coughing following strenuous swimming were related to hypoxaemia and reduction in lung volumes , suggesting pulmonary oedema. SIPO was a common and often recurrent phenom enon. Lower initial lung volumes and Rows might predict future susceptibili ty to SIPO. (C) 2000 Elsevier Science B.V. All rights reserved.