tell me the total amount of patient 31854's inputs on the current icu visit?
select sum(inputevents_cv.amount) from inputevents_cv where inputevents_cv.icustay_id in ( select icustays.icustay_id from icustays where icustays.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 31854 ) and icustays.outtime is null )