 Once on scene, the "Notarzt" performs all tasks associated with physicians in the field, acts as the Crew Chief, and provides medical direction to all subordinate EMS staff.Emergency physicians are dispatched along with a paramedic ambulance according to several standard dispatch criteria (indication catalogue, ""Notarzt-Indikationskatalog""), including myocardial infarction, dyspnoea, potential severe trauma, unconsciousness, life-threatening intoxication and needed pain management.Non-physician ambulance crews may request assistance by a "Notarzt" via dispatch as well.