what was the first value of sodium of patient 32154 in 01/2104?
select labevents.valuenum from labevents where labevents.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 32154 ) and labevents.itemid in ( select d_labitems.itemid from d_labitems where d_labitems.label = 'sodium' ) and strftime('%y-%m',labevents.charttime) = '2104-01' order by labevents.charttime asc limit 1