This is a prospective before and after study performed in a large metropolitan city. Cases were identified by review of all cardiac arrests called into a central medical control office. Data were collected through review of tapes and documentation obtained from routine quality assurance audits of these cardiac arrests at the dispatch office as well as reports written by paramedics at the scene of each case. Data were collected for 8 months prior to and 4 months after the implementation of a new dispatcher protocol designed to identify the presence of agonal breathing which included counting the respiratory rate, holding the phone next to the patient, and identifiers used to describe this type of breathing.
During the 8 months prior to implementation of the new protocol, no patient had agonal respirations detected compared with 22 patients detected in the 4 months after implementation. The percentage of patients who did not have EMD criteria for cardiac arrest, but actually were in cardiac arrest decreased from 28.0 % (168/599) to 18.8 % (68/362; p = 0.0012). Survival to ED admission was similar between the two groups. Bystanders started CPR significantly more frequently after the new protocol was instituted (60.9 % before vs. 71.5 % afterward, p = 0.006).
Introduction of a new 9-1-1 dispatcher assessment protocol to assess for the presence of agonal respirations can significantly increase the detection cardiac arrest over the telephone.