There were significantly lower mean volume of HES ( 42.85 3.93 versus 84 14.29 ml ) and percent of infants required it ( 30 % versus 90 % ) associated with earlier tolerance to oral feeding ( 2 0.66 versus 3.4 0.51 ) , shorter hospital stay ( 5.30 0.47 versus 6.7 [ symbols : see text ] days ) and lower rate of chest infection ( 15 % versus 30 % ) in Doppler group than clinical group .