Missed a line. The entry in the first column is again a record (Part two Order), with its serial number made by the unit he was in on the date given. It is his admission (adm) to the hospital. I would not like to guess what the initials in the first column are but as before, it is likely that his posting record or his medical record will have a clue relating to the date given.
Just an observation, when interpreting records it is almost always better to see it all as one has to look often at more than one sheet to get the answer. If my thoughts haven't clarified those lines, post the posting and medical record.
MaxD