Teaching recognition of agonal breathing improves accuracy of diagnosing cardiac arrest

Agonal breathing is present in up to 40% of pre-hospital cardiac arrests and is commonly mistaken as a sign of circulation leading to omission of bystander resuscitation. The aim of this study was to test the hypothesis that specific tuition on agonal breathing improves the accuracy of checking for signs of circulation as a diagnostic test for cardiac arrest.

First year medical students were randomised to control or intervention groups. The control group were taught standard CPR according to current guidelines. The intervention group received standard CPR training plus specific tuition on the characteristics of agonal breathing. Two weeks after initial training, the students' ability to recognise cardiac arrest was tested using a simulated cardiac arrest victim demonstrating normal, absent or agonal breathing. Diagnostic accuracy, sensitivity and specificity for the decision to start CPR was calculated.

Sixty-four students were equally randomised to intervention and control groups. The intervention group had greater diagnostic accuracy for cardiac arrest compared to the control group (90% versus 78%, P=0.03). The intervention group were more likely to recognise cardiac arrest correctly and initiate CPR than the control group (sensitivity 90% versus 78%, P=0.02). The improved results were predominantly due to recognition that agonal breathing is a sign of cardiac arrest (75% intervention group versus 43% control group, P=0.01).

This study demonstrates improved diagnostic accuracy and sensitivity of "checking for signs of circulation" by teaching CPR providers to recognise agonal breathing as a sign of cardiac arrest.