Flight microangiopathy in medium-to-long distance flights: prevention of edema and microcirculation alterations with HR (Paroven, Venoruton; 0-(beta-hydroxyethyl)-rutosides): a prospective, randomized, controlled trial.

This study evaluated the effects of HR (Paroven, Venoruton; 0-(beta-hydroxyethyl)-rutosides) on the prevention and control of flight microangiopathy, and particularly on edema, in subjects with varicose veins flying for more than 7 hours. Forty patients with varicose veins, edema, and initial skin alterations due to chronic venous hypertension were included. Measurements of skin laser Doppler flowmetry resting flux, Po(2) and rate of ankle swelling, were made before and after the flights (within 4 hours before the flights and within 2 hours after the flights). The length of the flights was between 7 and 9 hours; all seats were in coach class. The 2 groups were comparable for distribution. The variation of Po(2) was significant in both groups. However, in subjects treated with HR, the decrease in Po(2) was smaller (P < 0.05). The decrease in laser Doppler flowmetry resting flux was also significant in both groups, with a higher flux at the end of the control period in the treated subjects (P < 0.05). The venoarteriolar response progressively decreased at 7 and 9 hours. The decrease was less evident in the treatment group (P < 0.05). The rate of ankle swelling was progressively increased in the control group; the increase was not significant in the HR group. In long-haul flights, HR is useful for reducing the increased capillary filtration and in controlling edema in patients with venous hypertension and is effective in controlling perfusion disorders and microangiopathy, particularly swelling and edema, due to flights.