Air ambulance helicopter pilot reported an airborne conflict with a UAS while on approach to the helicopter pad.

Narrative

While on approach to the Hospital 'H' I noticed a drone at approach height. I called out the drone to the medcrew. As I continued my approach; the drone remained in its position; descending with my approach altitude. I monitored the drone during the approach and as I came to the pad the drone had descended to aprox 40 feet below the pad and remained 40 feet away. My crew immediately identified the drone and contacted security. The drone remained in a fixed location for another 15 min. I informed ATC that I would not continue flight operations until the drone had landed. We observed the drone; and it continued to operate in front of; behind and of the aircraft. The drone sporadically moved in all directions of the pad; eventually ending up in the approach area to the pad. The crew and myself monitored the drone until we noticed where the drone pilot was working.Suggestions: All drone operations should cease immediately when approaching aircraft are known to be arriving. ATC should inform helicopter pilots of all drone activity in the vicinity when helicopter traffic is known to be approaching - on arrival.