ALS Intercepts

Bureau of EMS Policy Statement
Policy Statement #98-09
SubjectALS Intercepts


Advanced Life Support (ALS) is an essential level of out-of-hospital medical care. Various predictors indicate that under ordinary situations 5 to 25 percent of all calls in a system will be for patients in need of ALS care. It is important that every prehospital patient needing ALS care receive it without delay and that all are transported to definitive care at a hospital in a timely fashion.

The policy serves to:

  • Define ALS intercepts.
  • Define parameters for the utilization of ALS as well as to provide objectives every intercept should meet
  • Minimize delay in transporting patients to definitive care at a hospital.
  • Enhance the provision of patient care by maximizing the availability of ALS for those patients identified as being in need of ALS care.
  • Provide guidelines to assist in identifying and accessing the most appropriate ALS service at the time of request.
  • Encourage REMACs to develop regional specific guidelines and protocols that enhance the availability of ALS and the appropriate use of ALS intercepts in the region.

New York State Statewide BLS Protocol

In 1996, the NYS BLS protocols were changed to introduce the concept of ALS intercepts and their use as the principal method of providing ALS care to patients needing this level of care when the initial EMS system contact is a BLS ambulance.

The provision of ALS by intercept permits the appropriate utilization of ALS resources by identifying a hospital or ALS service as the nearest ALS provider at the time of need. Call location, staffed ALS unit availability and/or direction of travel will effect the decision.

Excerpt from NYS BLS Protocol:

The goal of prehospital emergency medical care is DEFINITIVE CARE for the patient as rapidly and safely as the situation indicates with no deterioration of his/her condition and, when possible, in an improved condition. BLS units shall deliver their patients who will benefit from ALS care to this higher level of care as soon as possible. This may be accomplished either by intercepting with an ALS unit or by transport to an appropriate hospital, which ever can be effected more quickly.

A system of ALS intercept (when available within a given area) shall be pre-arranged. Formal written agreements for the request of ALS shall be developed in advance by those agencies not able to provide ALS.

A request for ALS intercept shall occur as noted in specific treatment protocols.

Initiation of patient transport shall not be delayed to await the arrival of an ALS unit, unless an on-line medical control physician otherwise directs.

Immediate Transport Decision:

Determine patient status (CUPS):
Critical or Unstable --- Immediate transport
Potentially Unstable -- Secondary survey and transport

If the patient's condition dictates immediate transport, the vital signs, secondary assessment, and treatment should be completed en route to the nearest appropriate hospital (as defined below in Section VII, Transport).

Intercept with an ALS unit (if available) en route to the nearest appropriate hospital as noted in specific treatment protocols.

Note: Do Not delay patient transport to await the arrival of an ALS unit.

ALS Intercepts

  • An intercept is an authorized and staffed ALS unit, dispatched by request or protocol, meeting a BLS unit while it is en route to the nearest appropriate hospital.
  • A BLS unit assesses the patient, determines the need for and requests ALS, packages and begins patient transport. The BLS unit shall not wait on the scene for the ALS unit's arrival. The request for ALS should be made as soon as the the patient's condition is recognized as needing ALS.
  • A hospital emergency department (ED) is the highest level of ALS medical care. Patients should be transported without delay to the nearest appropriate ED by the BLS unit. Definitive medical care can only be provided at a hospital ED.
  • ALS mutual aid is a misnomer and does not exist. The statutory definition of mutual aid(1) as well as the need for priority transport makes the use of the term "mutual aid" inappropriate in these circumstances.
  • BLS services should identify ALS services in advance which are staffed and readily available to provide ALS intercept. More than one service may need to be identified if the BLS service regularly transports to more than one hospital. All formal response agreement needs to be established in advance. Dispatch entities should monitor actual staffing and operational status of ALS resources to insure their availability at the time of the call and minimize any potential delay. The use of the "closest unit" concept is appropriate to dispatch ALS units.
  • All ALS patients should be transported to the hospital without delay by a BLS ambulance, particularly when the arrival of the ALS unit to the scene is estimated to be longer than the transport time to the hospital.
  • In developing ALS intercept relationships, REMACs must consider the patient's and ALS unit's proximity to the hospital. Patient transport to an emergency department should not be delayed. BLS/ALS care should ideally be administered en route.
  • Simultaneous dispatch of BLS and ALS resources should only be provided under the direction of dispatchers trained in the principals of emergency medical dispatch for those calls identified by a recognized dispatch algorithm.
  • REMACs should develop protocols that permit a certified provider who arrives on the scene after the time of dispatch, to cancel initially dispatched ALS resources when, after assessment, it is determined that ALS care is not needed.


1. Reference NYS-EMS Policy 95-04, "EMS Mutual Aid"

Issued: John J. Clair, Associtate Director - Operations

Authozed: Edward G. Wronski, Director