The waiver flying consideration of the pilots with kidney stone

Objective To observe the influence of flying on the movement of small kidney stones and to investigate the waiver flying qualification for the pilot with kidney stone.Methods The clinical data of 17 pilots with kidney stone,who were hospitalized from Sep.2005 to Jun.2012,and the fellow-up for their waiver flying were reviewed.Results All pilots were male and the average age was 34.4 yr.(from 23 to 46 yr.).Seven pilots had stones at left kidney,while 4 pilots had at right and 6 pilots had at both sides.All pilots received extracorporeal shock wave lithotripsy (ESWL) and drug or micro-invasive treatments,but there were still small kidney stones (2 to 4 mm in longitudinal diameter) left.No stone movement was found by exercise test and CT scan and the routine urine examination showed normal WBC and RBC numbers.Then they were qualified waiver flying.8 pilots were solely flying and the other 9 were co-piloting.The average waiver flying time was 110 h (from 30-240 h).The 8 were required to recheck in hospital by 3-month period while the 9 by 6-month rechecks,where they were inquired self symptoms and received CT scan and routine urine examination.The fellow-up showed no renal colic happened in air.Three co-piloting pilots complained lumbalis discomfort but colic while the stones were removed out on ground.The CT scan indicated that there were no more stones.There was no discomfort in other 14 pilots.The timely CT scan showed their stones had no change either on size or location and the routine urine examination results were normal.Conclusion The small kidney stone expelling will rarely cause renal colic if its size is less than 4 mm.The flying conditions do not promote the small stone movement in kidney.For the pilots with the kidney stone smaller than 3 mm,the assessment of waiver flying with close follow-up is feasible. Key words: kidney stone;  eligibility determination;  Aviation;  waiver flying