Unrecognized cardiac arrests: A one-year review of audio from emergency medical dispatch calls

Immediate recognition of out-of-hospital cardiac arrest (OHCA) by Emergency Medical Dispatch (EMD) operators is crucial to facilitate timely initiation of telephone cardiopulmonary resuscitation (T-CPR) and to enable the appropriate level of Emergency Medical Services (EMS) response. The goal of this study was to identify patterns that can increase EMD-level recognition of cardiac arrests prior to EMS arrival.

The Combined Communications Center in Alachua County, Florida provided audio recordings of all emergency calls from January 1, 2018 to November 16, 2018 dispatched as a chief complaint other than OHCA, but later identified as cardiac arrest. A multi-disciplinary medical team transcribed and analyzed the calls to determine common themes and trends.

Out of an initial 81 calls meeting inclusion criteria, 69 were immediately recognized as OHCA by EMDs, leaving 12 calls of unrecognized OHCA. In 11 of 12 calls respiratory issues were described to EMD. In 10 of 12 calls the subject was described as unconscious, and in the other 2 calls, the subject lost consciousness during the call.

Lack of recognition of OHCA by EMD occurred in most calls due to difficulty communicating the subject's respiratory status. Further emphasis should be placed on identifying non-viable respirations in unconscious patients in EMD training and algorithms to increase recognition of OHCA and initiation of T-CPR. A multi-year review of a comparable dataset from geographically and socioeconomically diverse regions in the United States can validate and expand these preliminary trends.