calculate the total or urine production for patient 6705 on the last icu visit.
select sum(outputevents.value) from outputevents where outputevents.icustay_id in ( select icustays.icustay_id from icustays where icustays.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 6705 ) and icustays.outtime is not null order by icustays.intime desc limit 1 ) and outputevents.itemid in ( select d_items.itemid from d_items where d_items.label = 'or urine' and d_items.linksto = 'outputevents' )