instruction: until 3 years ago how many patients received therapeutic antibacterials - fourth generation cephalosporin during the same month after the diagnosis of hypotension.
response: SELECT COUNT(DISTINCT t1.uniquepid) FROM (SELECT patient.uniquepid, diagnosis.diagnosistime FROM diagnosis JOIN patient ON diagnosis.patientunitstayid = patient.patientunitstayid WHERE diagnosis.diagnosisname = 'hypotension' AND DATETIME(diagnosis.diagnosistime) <= DATETIME(CURRENT_TIME(), '-3 year')) AS t1 JOIN (SELECT patient.uniquepid, treatment.treatmenttime FROM treatment JOIN patient ON treatment.patientunitstayid = patient.patientunitstayid WHERE treatment.treatmentname = 'therapeutic antibacterials - fourth generation cephalosporin' AND DATETIME(treatment.treatmenttime) <= DATETIME(CURRENT_TIME(), '-3 year')) AS t2 WHERE t1.diagnosistime < t2.treatmenttime AND DATETIME(t1.diagnosistime, 'start of month') = DATETIME(t2.treatmenttime, 'start of month')