It was an ordinary day on duty in our dialysis centre. One of my regular patients had arrived for his usual hemodialysis session. I was quite close to him — I often joked with my patients, tried to make them smile. Dialysis can feel endless, and a little laughter lightens the hours. He usually came in with high blood pressure, so I always checked his BP before starting. But that day, the machine was not working. I told myself I would keep an eye on him instead, checking in frequently to see if he looked uncomfortable or showed any signs of hypertension. The session went smoothly at first. Everything seemed…