how many hours has it been since the first time patient 19428 stayed in careunit ccu in their current hospital visit.
select 24 * ( strftime('%j',current_time) - strftime('%j',transfers.intime) ) from transfers where transfers.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 19428 and admissions.dischtime is null ) and transfers.careunit = 'ccu' order by transfers.intime asc limit 1