Emergency Medical Dispatch (EMD) refers to a system that enhances services provided by Public Safety Answering Point (emergency) call takers, such as municipal emergency services dispatchers. It does so by allowing the call taker to quickly narrow down the caller's type of medical or trauma situation, so as to better dispatch emergency services, and provide quality instruction to the caller before help arrives.

Overview

Based on specific question-and-answer logic trees ("systematized interrogation"), the dispatcher is able to determine a problem type and priority for the call, and use that information to

• provide systematized Pre-Arrival Instructions, including
  • Dispatch Life Support (DLS), which gives phone instruction to aid the patient until help arrives
  • provide other information to the caller
• activate appropriate protocols
  • dispatch the call to the appropriate resources
  • dispatch using the appropriate modes (emergency mode or normal driving)
  • activation of secondary protocols, such as notifications

Implementation

Many countries have a national EMD or DLS program, sometimes with a designated system provider, either mandatory or optional. Others may have a national curriculum or accreditation program, or the program may be designated by local jurisdictions at the state or province level. Not all jurisdictions have any sanctioned EMD or DLS system in place, and not all emergency call centers have EMD or DLS. There is some controversy over using these systems, especially when non-medical staff man the phones.

EMD may be guided by computer software, or flashcard-books (often color coded, with page cross references to help further narrow down the phone diagnosis and/or treatment, and dispatch protocol). Such manual systems have been likened to recipe cards.

The dispatch effort guided by EMD may indicate call severity, resource type (basic life support

Basic life support

Basic life support is the level of medical care which is used for patients with life-threatening illnesses or injuries until the patient can be given full medical care at a hospital. It can be provided by trained medical personnel, including emergency medical technicians, paramedics, and by...

 or paramedics), declaration of a multiple casualty incident (MCI), responder emergency mode (e.g., permission to use lights and sirens), call priority, and hospital or health department notification.

The on-phone instruction effort guided by EMD may help the caller or other bystander to perform CPR or other lay basic life support, provide instruction on how to aid the responders to reach the patient, evacuation instructions, or other forms of care or safety instruction.

Adopted programs

In the United States, the Medical Priority Dispatch System

Medical Priority Dispatch System

The Medical Priority Dispatch System is a medically-approved, unified system used to dispatch appropriate aid to medical emergencies including systematized caller interrogation and pre-arrival instructions. Priority Dispatch Corporation is licensed to design and publish MPDS and its various...

 (MPDS), Criterion-Based Dispatch, and Computer aided call handling

Computer aided call handling

Computer aided call handling is a methodology for managing calls to service providers, such as emergency services, through the use of computer based algorithms in order to make consistent and objective decisions on action to be taken...

 (CACH) are common protocols.

In the United Kingdom, AMPDS is the nationally approved computer program for EMD.