I heard from a doctor that one of the South African air ambulances (J'berg EC135), was once blades turning for >24hrs continuously attending in the region of 10 patients with rotors running refuels and patient loading/unloadings. The pilot would drop the crew and patient off at A&E, unload rotors running, lift to the hems base next door, unstrap and fuel the aircraft, then hop back in and fly back to the A&E, pick up crew and off to the next patient...
Presumably there was a shift swap in there somewhere, why not shut down for that? I'm not sure on the details - does anyone know any more about this? Apparently Eurocopter said it was the first time they'd heard of it happening.