Available mean time for active expansion in the CO2 group was 18.2 ( 9.2 ) days ( median , 14.0 ; range , 5-39 ; number of expanders , 53 ) , which was less than the mean time for active expansion in the saline group : 57.4 ( 33.6 ) days ( median , 55 ; range , 5-137 ; number of expanders , 33 ) .