how many days has elapsed since the first time during their current hospital visit patient 28443 had received a creatine kinase (ck) lab test?
select 1 * ( strftime('%j',current_time) - strftime('%j',labevents.charttime) ) from labevents where labevents.itemid in ( select d_labitems.itemid from d_labitems where d_labitems.label = 'creatine kinase (ck)' ) and labevents.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 28443 and admissions.dischtime is null ) order by labevents.charttime asc limit 1