A comparative analysis showed a significant improvement of spirometric parameters in the intervention group ; pre-to-post hospitalization predicted values showed significant changes in vital capacity ( @ @ % to @ @ % , P < @ ) , forced expiratory volume in first second ( @ @ % to @ @ % , P < @ ) and forced expiratory flow at @-@ % ( @ @ % to @ @ % , P = @ ) compared to the control group that showed no significant changes across treatment .