ผู้ป่วย 021-25408 มีระดับ sao2 ปกติในการเข้ารับการตรวจไอซียูครั้งล่าสุดหรือไม่? ไม่จำเป็นต้องใช้ตารางทั้งหมด
did patient 021-25408 have normal levels of sao2 on the last icu visit?It is not neccessary to use all the tables.
 patient:  uniquepid [ text]  patienthealthsystemstayid [ number]  patientunitstayid [ number]  gender [ text]  age [ text]  ethnicity [ text]  hospitalid [ number]  wardid [ number]  admissionheight [ number]  admissionweight [ number]  dischargeweight [ number]  hospitaladmittime [ time]  hospitaladmitsource [ text]  unitadmittime [ time]  unitdischargetime [ time]  hospitaldischargetime [ time]  hospitaldischargestatus [ text] 
SELECT COUNT(*) > 0 FROM vitalperiodic WHERE vitalperiodic.patientunitstayid IN (SELECT patient.patientunitstayid FROM patient WHERE patient.patienthealthsystemstayid IN (SELECT patient.patienthealthsystemstayid FROM patient WHERE patient.uniquepid = '021-25408') AND NOT patient.unitdischargetime IS NULL ORDER BY patient.unitadmittime DESC LIMIT 1) AND vitalperiodic.sao2 BETWEEN sao2_lower AND sao2_upper AND NOT vitalperiodic.sao2 IS NULL