Telephone-cardiopulmonary resuscitation (CPR), in which an Emergency Call Handler provides CPR instructions to a caller, has been shown to double the rate of bystander-CPR engagement. The life-saving benefit of the provision of early commencement of CPR is well documented across the literature. Yet, bystander-CPR rates remain relatively low. There is currently no literature in New Zealand which describes or compares the ability of an Emergency Call Handler to accurately recognise out-of hospital-cardiac-arrest (OHCA) over the phone. Additionally, there are no documented timeframes which measure the time intervals associated with the recognition of OHCA, the commencement of telephone-CPR and the commencement of the first chest compression. The primary aim of this study is to establish the accuracy of Emergency Call Handler recognition of cardiac arrest in New Zealand. The secondary aims of this study are to measure: (i) the time taken from emergency call pick-up to: • the recognition of OHCA; • the commencement of telephone-CPR instructions; • the commencement of the first chest compression by a bystander. (ii) bystander-CPR rates.

A retrospective observational study was conducted using data collected from calls placed to the Clinical Communication Service centres in New Zealand during the period 1 April and 30 April 2016 involving OHCA events. After reviewing the audio files of OHCA events, the sensitivity was calculated by measuring the Emergency Call Handlers’ ability to accurately recognise OHCA which was then compared to the attending paramedic’s findings upon arrival on scene. The median times and interquartile ranges (IQR) associated with the intervals for the Emergency Call Handler to recognise OHCA, commence telephone-CPR instructions and to begin the first chest compression guided by telephone-CPR instructions were recorded. Finally, the rate of bystander CPR was established.

The sensitivity of Emergency Call Handlers’ recognition of OHCA was 98%. The median duration of delay from call pick-up to OHCA recognition was 105 seconds (IQR 80-148), the median time taken to the commencement of telephone-CPR instructions was 146 seconds (IQR 109-212) and the median time from call pick-up to the commencement of the first chest compression was 255 seconds (IQR 201-342).

Bystander CPR was in progress when the EMS crew arrived with the patient in 53% of all cases and 70% of cases when the Emergency Call Handler provided telephone CPR instructions.

This study identifies that while the overall rate recognition of OHCA by Emergency Call Handlers in New Zealand is excellent, there is room for improvement in the delay from call pick-up to recognition, initiation of telephone-CPR instructions and the commencement of bystander compressions. All these intervals were longer than American Heart Association guidelines. A higher rate of bystander rate CPR was observed in cases where telephone-CPR instructions were given compared to those where instructions were not supplied.