Why was John uneasy during the hospital visit in the pigman?

John was uneasy during the hospital visit in "The Pigman" because he was uncomfortable seeing Mr. Pignati, whom he had grown close to, in a vulnerable and weakened state. Additionally, John felt guilty for his role in Mr. Pignati's heart attack and was overwhelmed by the realization of how much Mr. Pignati cared for him and Lorraine.