Out-of-Hospital Medical Direction and the Intervener Physician

Revised January 2016

Rescinded October 2015 

Revised April 2015, April 2008 titled “Direction of Out-of-Hospital Care at the Scene of Medical Emergencies” 

Reaffirmed October 2001, October 1997 

Revised October 1993 titled “Direction of Prehospital Care at the Scene of Medical Emergencies” 

Originally approved April 1984 titled “Control of Advanced Life Support at the Scene of Medical Emergencies”


The American College of Emergency Physicians (ACEP) believes that the direction of out-of-hospital care at the scene of a medical emergency should be the responsibility of the individual in attendance who is most appropriately trained and knowledgeable in providing out-of-hospital emergency care and transport. This is typically a certified EMS provider acting as part of the responding EMS agency.

During routine operations, the out-of-hospital provider is responsible for management of the patient and acts as an agent of the EMS medical director. 

This document should guide but not usurp local protocols specifically addressing these issues. This position does not apply when the intervener is an EMS physician within the given EMS system.

Notwithstanding the special situations noted below, the out-of-hospital provider:

  • shall act only within the provider’s scope of practice.
  • has a duty to re-establish medical direction with the on-line physician if the out-of-hospital provider believes that the emergency care rendered by the scene physician is inconsistent with standard of care.
  • reverts to off-line medical direction (ie, existing EMS protocols) or on-line medical direction for the continued management of the patient
    • at any time when the scene physician is no longer in attendance.
    • if the treatment at the emergency scene differs from existing EMS protocols and is contradictory to quality patient care.  

However, in some cases, a physician on scene may assume responsibility for patient care and provide medical direction. 

If the private physician is present (as may occur in a physician’s office) and assumes responsibility for the patient’s care:

The out-of-hospital provider should defer to the orders of the private physician. On-line medical direction, if that capability exists, should be contacted for record keeping purposes and possible collaboration with the treating physician.

If an intervener physician is present and on-line medical direction is not available:

The out-of-hospital provider at an emergency scene should relinquish responsibility for patient management when the intervener physician has:

  1. been properly identified
  2. agreed to assume responsibility
  3. agreed to document the intervention in a manner acceptable to   the local emergency medical services system (EMSS)
  4. agreed to accompany the patient to the hospital, with the potential exception of a mass casualty incident or disaster.

When all of these conditions exist, the out-of-hospital provider should defer to the wishes of the physician on the scene. Despite the presence of this physician on scene, the out-of-hospital provider shall only act to the limit of their scope of practice.

If an intervener physician is present and on-line medical direction is available:

The on-line physician is ultimately responsible. It is the on-line physician’s option to manage the case entirely, work with the intervener physician, or allow the intervener physician to assume responsibility. In the event:

  1. of disagreement between the intervener physician and the on-line physician, the out-of-hospital provider should take orders from the on-line physician and place the intervener physician in contact with the on-line physician.
  2. the intervener physician assumes responsibility, all orders to the out-of-hospital provider should be repeated over the radio for purposes of recording. The intervener physician should document the intervention in a manner acceptable to the local EMSS.
  3. the out-of-hospital provider or on-line medical direction believes that the emergency care rendered by the intervener physician is inconsistent with EMS protocols and quality patient care, on-line medical direction should be reestablished. The decision of the intervener physician to accompany the patient to the hospital should be made in consultation with the on-line physician.

If a disaster or mass casualty situation exists:

An EMS physician shall provide medical oversight within the established command and control system.

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