what was the number of times that patient 15209 had ct gent gtt intake on the last icu visit?
select count(*) 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 = 15209 ) and icustays.outtime is not null order by icustays.intime desc limit 1 ) and inputevents_cv.itemid in ( select d_items.itemid from d_items where d_items.label = 'ct gent gtt' and d_items.linksto = 'inputevents_cv' )