Treatment table: activeupondischarge

[Yannis-ys]

Dear Doctors, Hi! I am working on the Treatment table, but I am confused with the column named activeupondischarge, especially when the treatment is an operation/surgery. For example, the patient with patientunitstayid = 310067 had 6 records of cardiac surgery/CABG, and only the last record has a "True" activeupondischarge. How to understand the 6 records? whether the time of the first record is the start time of the surgery and the time of the last record is the end time of the same surgery? Moreover, some patients' surgery records are all "False" (For example, patientunitstayid=312706, 312707), have they received surgery? Thank you very much!