FIGURE 134.2 Sample offline patient care guideline (From Utah Department of Health, Bureau of EMS.) 9-1-1 calls are answered at a public safety answering point (PSAP) There, Emergency Medical Dispatchers are specially trained in emergency medical dispatch (EMD) to prioritize calls, determine the appropriate level of response (EMR, BLS, or ALS), give callers prearrival instructions, and stay on the line with the caller to provide support Formal EMD systems exist in guide card and electronic formats Using structured, protocol-driven caller interrogation, dispatchers follow scripted medical protocols based upon the chief complaint The goal of standardized dispatch is to send “the right resource in the right mode at the right time.” EMS systems vary in the configuration of personnel into units or teams Some systems have EMT-only units, while other systems may have EMTs partnered with paramedics in all units In a tiered system , there is a set of criteria that determine whether an ALS or BLS response is indicated and dispatched, based on the scripted caller interrogation For example, a call for an isolated minor foot injury would receive a BLS unit, while a call for a seizure would receive an ALS ambulance In a nontiered system , the highest level of provider is dispatched to all calls Based on local policies, other resources such as police and fire units may be dispatched along with EMS It should be a goal in every community to have reliable medical advice available for the 9-1-1 caller while awaiting EMS response The importance of EMD has been underscored by increased recognition and research For instance, dispatcher-assisted CPR increases rates of bystander CPR, and bystander CPR has been associated