what is the total amount of syringe (neonatal) *d5w* prescribed to patient 6170 since 12/2105?
select sum(prescriptions.dose_val_rx) from prescriptions where prescriptions.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 6170 ) and prescriptions.drug = 'syringe (neonatal) *d5w*' and strftime('%y-%m',prescriptions.startdate) >= '2105-12'