Tonight, the largest nurse and health care professional union in Massachusetts is holding vigils across the commonwealth to honor Alex Pretti. WAMC: The Massachusetts Nurses Association is one of the largest labor unions in the commonwealth. Now, today, the union is holding these memorials across the commonwealth for the late ICU nurse Alex Pretti. What kind of work does an ICU nurse expect to see over the course of a given shift? We consider- He's one of us, both because he's a bedside nurse, he's also a union member- And he's caring for veterans.