A new study that investigated whether a photoplethysmography sensor in a smart watch could be useful for detecting the return of spontaneous circulation (ROSC) in cardiac arrest patients has found that smart watches have the same sensitivity and a higher specificity for recognising ROSC than manual pulse check when measured at the wrist.
The prospective study was conducted on 50 out-of-hospital cardiac arrest patients who attended an emergency department of one tertiary hospital.
Advanced cardiac life support was carried out immediately on patients on arrival at the hospital. Three smart watches were simultaneously attached to the carotid artery, forehead and wrist of patients and were checked for pulse measurements every two minutes. Palpation was conducted by one emergency physician from the cardiopulmonary resuscitation (CPR) team.
In 14 patients (28%), spontaneous circulation recovered through CPR, and all survived.
The study found the sensitivity and specificity of manual palpation were 78.6 per cent and 90.4 per cent, respectively. The smart watches at all three sites had the same or higher sensitivity than manual palpation.
The authors noted a number of limitations to the study including that just one smart watch (Galaxy Fit) was used. The findings are published in the BMJ Open.