RT Journal Article
SR Electronic
T1 Assessment of the feasibility of an ultra-low power, wireless digital patch for the continuous ambulatory monitoring of vital signs
JF BMJ Open
JO BMJ Open
FD British Medical Journal Publishing Group
SP e006606
DO 10.1136/bmjopen-2014-006606
VO 5
IS 5
A1 Hernandez-Silveira, Miguel
A1 Ahmed, Kamran
A1 Ang, Su-Shin
A1 Zandari, Fahriya
A1 Mehta, Tinaz
A1 Weir, Rebecca
A1 Burdett, Alison
A1 Toumazou, Chris
A1 Brett, Stephen J
YR 2015
UL http://bmjopen.bmj.com/content/5/5/e006606.abstract
AB Background and objectives Vital signs are usually recorded at 4–8 h intervals in hospital patients, and deterioration between measurements can have serious consequences. The primary study objective was to assess agreement between a new ultra-low power, wireless and wearable surveillance system for continuous ambulatory monitoring of vital signs and a widely used clinical vital signs monitor. The secondary objective was to examine the system's ability to automatically identify and reject invalid physiological data.Setting Single hospital centre.Participants Heart and respiratory rate were recorded over 2 h in 20 patients undergoing elective surgery and a second group of 41 patients with comorbid conditions, in the general ward.Outcome measures Primary outcome measures were limits of agreement and bias. The secondary outcome measure was proportion of data rejected.Results The digital patch provided reliable heart rate values in the majority of patients (about 80%) with normal sinus rhythm, and in the presence of abnormal ECG recordings (excluding aperiodic arrhythmias such as atrial fibrillation). The mean difference between systems was less than ±1 bpm in all patient groups studied. Although respiratory data were more frequently rejected as invalid because of the high sensitivity of impedance pneumography to motion artefacts, valid rates were reported for 50% of recordings with a mean difference of less than ±1 brpm compared with the bedside monitor. Correlation between systems was statistically significant (p<0.0001) for heart and respiratory rate, apart from respiratory rate in patients with atrial fibrillation (p=0.02).Conclusions Overall agreement between digital patch and clinical monitor was satisfactory, as was the efficacy of the system for automatic rejection of invalid data. Wireless monitoring technologies, such as the one tested, may offer clinical value when implemented as part of wider hospital systems that integrate and support existing clinical protocols and workflows.