What do you do when someone says 'I'm fine'?

It’s the quietest lie I’ve heard in a decade. Not dramatic, not even sad—just a flat line on a monitor that everyone pretends is normal. I keep thinking about how many people have said it to me in the ICU, and how I used to nod and move on. Now I just… wait. Like the air between breaths. What do you do when the silence after 'I’m fine' feels heavier than any scream?