Clinical Validation of Dozee’s Contactless Vital Sign Measurements

The most common parameters supervised by healthcare professionals to monitor patients’ health are heart rate (HR), respiration rate (RR), blood pressure (BP), oxygen saturation (SpO2), and temperature1

Conventional techniques for continuous monitoring of HR and RR rely on sophisticated equipment like multi-lead ECG sensors2 and nasal thermistors or nasal cannulas3. Continuous BP measurement typically involves intra-arterial BP monitoring (ABP), where a catheter is inserted into the artery for continuous BP monitoring4. However, ABP procedures are invasive and pose risks such as infection, bleeding, and thrombosis5. They are mainly restricted to Intensive Care Units (ICU) and are usually limited to critically ill patients, sometimes discontinued within a week due to discomfort and complications. For other hospitalized patients, periodic non-invasive cuff-based BP (NiBP) measurements are common, often done once a day. However, obtaining these readings can be difficult, disruptive (especially during sleep), and unreliable6,7. These traditional methods for HR, RR, and BP measurements are cumbersome and necessitate a high level of patient cooperation, as well as clinical expertise for accurate implementation.

Turtle Shell Technologies Pvt. Ltd. ’s (TST) Dozee system is a non-invasive continuous vitals monitoring system. The device employs piezoelectric sensors to capture micro-vibrations caused by cardiac contractions, upper respiratory tract activity, and body movements. It is based on the concept of ballistocardiography (BCG). The Dozee system is made up of non-contact sensor sheet(s) whose signals are used to calculate HR, RR, and non-contact blood pressure (NcBP). To measure temperature,  SpO2, and NiBP, contact accessories such as pulse oximeter, temperature probe, and cuff BP  respectively have been integrated.

This is a single-arm, unblinded, prospective, observational non-randomized study. The study will include 400 +ICU patients who provide consent. This study is considered an observational study as no Dozee data will be shared with clinical staff or the subject that may influence care. The study duration of enrolment for each patient will be 24hrs-72hrs.

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