Reliability of heart rate and respiration rate measurements with a wireless accelerometer in postbariatric recovery

Abstract

Recognition of early signs of deterioration in postoperative course could be improved by continuous monitoring of vital parameters. Wearable sensors could enable this by wireless transmission of vital signs. A novel accelerometer-based device, called Healthdot, has been designed to be worn on the skin to measure the two key vital parameters respiration rate (RespR) and heart rate (HeartR). The goal of this study is to assess the reliability of heart rate and respiration rate measured by the Healthdot in comparison to the gold standard, the bedside patient monitor, during the postoperative period in bariatric patients. Data were collected in a consecutive group of 30 patients who agreed to wear the device after their primary bariatric procedure. Directly after surgery, a Healthdot was attached on the patients’ left lower rib. Vital signs measured by the accelerometer based Healthdot were compared to vital signs collected with the gold standard patient monitor for the period that the patient stayed at the post-anesthesia care unit. Over all patients, a total of 22 hours of vital signs obtained by the Healthdot were recorded simultaneously with the bedside patient monitor data. 87.5% of the data met the pre-defined bias of 5 beats per minute for HeartR and 92.3% of the data met the pre-defined bias of 5 respirations per minute for RespR. The Healthdot can be used to accurately derive heart rate and respiration rate in postbariatric patients. Wireless continuous monitoring of key vital signs has the potential to contribute to earlier recognition of complications in postoperative patients. Future studies should focus on the ability to detect patient deterioration in low-care environments and at home after discharge from the hospital.

Accuracy of vital parameters measured by a wearable patch following major abdominal cancer surgery

“…The 5-min averaged data was in the clinically acceptable regions for at least 99% of both HR and RR measurements, therefore we conclude that the clinical performance of the Healthdot in the current cohort is good. The accuracy of the Healthdot for 5-min averaged data was previously studied in bariatric patients where 90.5% of the HR measurements were within the 5 bpm and 88.5% of the RR measurements were within the 3 rpm threshold [13]. The higher percentages found in the present study could be explained by the higher BMI in the bariatric study population as the presence of subcutaneous fat around the chest might impair accelerometer measurements.…”

“…The Healthdot and reference monitor measurements were synchronized based on the temporal sequence of HR values by applying a means of cross-correlation and by applying manual correction when needed in order to define time offset and drift between the clock of the two devices. Any clock drift were corrected by using linear interpolation of the time base for the Healthdot dataset [13]. Patients with a reference recording length of at least 30 min were included in the analysis.…”

“…The hypothesis was that contraction of the atria followed by the ventricles could be assessed by the Healthdot as separate heart beats. Consequently, the calculated heartrate is doubled [13]. These 'doubled' HR measurements could unnecessarily trigger undesirable alarms in clinical practice.…”

“…The measured HR and RR are transmitted via a nationwide low-power wide-area network (LoRa) both in-and outside the hospital. The accuracy of the Healthdot was previously studied in post-operative bariatric patients [13]. This population is characterized by a short postoperative hospital stay and low complication rate.…”

Continuous remote monitoring in post–bariatric surgery patients: development of an early warning protocol

“…Vital parameters were measured using Healthdot (Philips Electronics, Netherlands). Healthdot is a validated remote wearable sensor for continuous measurements of heart rate and respiration rate (RR) based on accelerometer measurements [13]. The device is attached under the lower left rib and can be worn for 14 days (Supplemental Fig.…”