A steadier ground guide to the hospital stay, where new confusion in the first days is common and usually treatable, and where the person who knows him is the most useful instrument on the ward. What may be happening, what to say to him and to the staff, and when "worse" means something that needs a nurse now.
Notice the urge to apologize for him, or to explain him, every time a new person walks into the room. The confusion you are watching is frightening, and it is yours to feel, and one breath before the next nurse arrives keeps your voice the steady thing in a room that has none.
Before anything else: a person with dementia who becomes newly confused in hospital is often in delirium, which is a medical change layered on top of the dementia rather than the dementia moving faster. Pain, an infection, dehydration, constipation, a bladder that will not empty, a new medicine, and glasses or hearing aids left in a drawer at home are the ordinary causes, and most of them are treatable once someone hears that this is new.
Delirium is common on a hospital ward and it is missed constantly, because new confusion in someone who already has dementia looks like more of the same to anyone who did not know him last week. It fluctuates, so he can be nearly himself at ten in the morning and unreachable by four. Attention goes first, so he loses the thread mid-sentence and cannot hold a question long enough to answer it. And it runs in two directions. The agitated version, pulling at lines and trying to climb out of bed, gets noticed. The quiet version, where he goes drowsy, withdrawn and hard to rouse, gets charted as resting comfortably, and it carries the same risk.
The building does its share. Lights that never go off, alarms, strangers every few hours, no window to read the time of day from, an IV line and a monitor that pin him to the bed, meals in sealed packaging he cannot open. Take away movement, sleep, food, water, glasses and hearing aids at once and a brain that was managing at home has nothing left to manage with. When he pulls at a line or tries to get up, that is usually a body trying to get comfortable or find a bathroom. It gets read as behavior, which is how a sedative or a restraint arrives, and both deepen the delirium they were meant to control.
And nobody on the ward knows his baseline. They know his chart. A man who followed a conversation on Tuesday and cannot follow one on Thursday looks, to a nurse meeting him on Thursday, like a man with dementia. You are the only person in the building who can say that Thursday is not normal. Being there and saying it plainly is not a courtesy. It is the instrument the ward does not have.
You cannot treat the infection or rewrite the medication list, and you can change most of what the room is doing to him.
Write down the hour he is clearest and the hour he is worst, what he ate and drank, when he last passed urine, and how he slept, dated. The ward records vital signs; nobody records that he was himself at ten and gone by four, and that pattern is what makes delirium visible to the next doctor who rounds. If a new medicine was added, note the day, since the confusion that follows it is the most reversible kind.
Print the emergency room handoff and the one-page log: the handoff for the front desk, the log for the ward.
This is what the tracking is for. On a ward the clinician is the nurse at the bedside, and the hour it started and the hour it changed are what turn "he seems worse" into a page to the doctor.
The ward measures him against his chart, and you measure him against Tuesday. Yours is the measurement that catches this, and it does not need a medical word to be true. Sitting in the chair by the bed without answers is most of the job.