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Comprehensive Assessment of Emergency Medical Services 71 <br />and 911 /Communications Center Operations Study <br />Issue: Response Time <br />For the purposes of this report and as referenced in Subsection 2.3, EMS ambulance response time is: <br />The time from the initial alert or announcement by the Communications Center (also called "tone', <br />"page"; or "dispatch ") of the reported emergency, to the time that the service vehicle and appropriate <br />personnel arrive on the scene. <br />The factors that most commonly impact response time include: <br />• The time required to access and engage the vehicle, <br />• The speed at which the emergency vehicle is able to travel, <br />• The distance that must be covered to the incident dispatched, and <br />• Under what conditions. <br />Consequently, the basis upon which pre - hospital emergency medical response criteria has been <br />established is medical case history data regarding the body's need for oxygen. Simply, the human body <br />needs oxygen to survive. While some cells may tolerate short periods without oxygen, most require a <br />constant supply of oxygen to survive. Figure 21 illustrates the significance of time in this equation. <br />Figure 21 <br />Concerns and subsequent standards regarding <br />emergency medical response times are based on the <br />findings of various significant medical organizations <br />and professional associations. Among these, the <br />American College of Emergency Physicians (ACEP) <br />and the American Heart Association has each <br />similarly stated: <br />"The most important factor in successfully <br />resuscitating a patient in cardiac arrest is the speed <br />of response. The survival rate from untreated <br />ventricular fibrillation decreases up to 10% for every <br />minute that passes and definitive care is not <br />provided." <br />minute; cardiac irritability <br />minutes; brain damage not likely <br />minutes; brain damage possible <br />1 minutes; brain damage very likely <br />minutes; irreversible brain damage <br />The American Heart Association, ACEP, and other respected organizations recommend that EMS <br />vehicles should respond to deliver BLS (basic life support) skills within 3 to 4 minutes, with ALS <br />(advanced life support) skills available within 6 to 8 minutes. The ALS- within -8- minute concept was <br />developed from research that showed the survival rate of cardiac arrest victims decreases significantly <br />with each passing minute, and that optimal probabilities for survival increase when BLS has been <br />provided within 4 minutes followed by ALS within 8 minutes. "' <br />In addition, <br />■ The American Association of Orthopedic Surgeons (source of Figure 21) suggests that "in an <br />incident involving lack of oxygen, brain damage is very likely at 6 to 8 minutes; irreversible after <br />10 minutes." <br />■ The National Fire Protection Association states in NFPA 1710 that AED (BLS) capabilities must <br />arrive within a 4- minute response time to 90% of the incidents; and that ALS capabilities shall be <br />deployed to arrive within an 8- minute response time to 90% of the incidents. <br />7 American College of Emergency Physicians; "Principles of EMS Systems "; 2006 <br />Solutions for Local Government, Inc. 27 <br />