This project aims to develop a low-cost, comfortable, and easy-to-use wearable alert system that tracks continuous BP non-invasively in patients to notify caregivers of hypotensive events in the postoperative setting. Postoperative hypotension (POH), when a patient's mean arterial pressure (MAP) falls to unsafe levels, commonly <70 mmHg, can occur frequently in the time span between leaving the operating room and prior to discharge from the hospital. POH is a serious and common condition that has been shown to be independently associated with poor patient outcomes such as acute kidney injury, stroke, hospital re-admission, myocardial injury, and death.1-9 During surgery and recovery in the post anesthesia care unit (PACU) or the intensive care unit (ICU), a patient's hemodynamics are closely monitored to support timely interventions and treatment. However, once the patient is transferred to a lower ward for recovery, patient monitoring is dramatically reduced. The current method to monitor a patient's BP in the general ward, which relies on intermittent spot-checks performed manually every 4-6 hours by the nurse using an oscillometric BP cuff, is insufficient for detecting POH events. A recent study showed that almost 50% of hypotensive events went undetected by routine vital assessments. There is an unmet need for a technology that comfortably monitors a patient's BP in the postoperative setting. Our core technology is able to non-invasively measure rapid BP changes at any location with a palpable pulse. The proposed project aims build upon the core technology to create a wearable alert system that informs caregivers of postoperative hypotensive episodes. To do so, a machine learning (ML) classifier for detection of hypotensive episodes will be developed through monitoring in the ICU. This ML classifier will undergo feasibility testing in the PACU and then a pilot study in the general ward. Successful completion of the proposed aims will result in a proof- of-concept wearable alert system that continuously monitors BP in the postoperative environment in a low-profile, wireless, and comfortable manner. Such a technology has huge potential to change clinical practice through earlier detection of patient deterioration, allowing more timely intervention and ultimately improved patient outcomes.
Public Health Relevance Statement: Project Narrative This project seeks to develop a wearable alert system for detecting postoperative hypotensive episodes in patients by directly measuring continuous beat-to-beat blood pressure in a comfortable and unobtrusive manner. It is known that postoperative hypotension is common but can go undetected by current patient monitoring methods, thus resulting in poor patient outcomes. The Vena Vitals wearable alert system will detect when a patient's mean arterial pressure drops below a defined threshold level and alert caregivers of hypotensive events; such a system has significant potential to improve clinical practice by enabling caregiver intervention, preventing patient deterioration, and improving cost efficiency for the hospital.
Project Terms: Anesthesia; Anesthesia procedures; Arterial Lines; Intra-Arterial Lines; Blood Pressure; Cessation of life; Death; Environment; Follow-Up Studies; Followup Studies; hemodynamics; Hospitals; Hypotension; Low Blood Pressure; Vascular Hypotensive Disorder; Intensive Care Units; Manuals; Methods; United States National Institutes of Health; NIH; National Institutes of Health; Nurses; nurse; Operating Rooms; Patient Monitoring; Patients; Personal Satisfaction; well-being; wellbeing; Pilot Projects; pilot study; Postoperative Period; Post-Operative; Postoperative; pressure; Resources; Research Resources; Risk; Sensitivity and Specificity; Signal Transduction; Cell Communication and Signaling; Cell Signaling; Intracellular Communication and Signaling; Signal Transduction Systems; Signaling; biological signal transduction; Stroke; Apoplexy; Brain Vascular Accident; Cerebral Stroke; Cerebrovascular Apoplexy; Cerebrovascular Stroke; brain attack; cerebral vascular accident; cerebrovascular accident; stroked; strokes; Technology; Time; General Ward; Measures; Care Givers; Caregivers; falls; Caring; improved; Phase; Recovery; Funding; Spottings; Physiologic pulse; Pulse; Notification; Hour; Frequencies; Event; System; Location; Palpable; palpable disease; Operative Surgical Procedures; Operative Procedures; Surgical; Surgical Interventions; Surgical Procedure; surgery; Acute Renal Failure with Renal Papillary Necrosis; acute kidney injury; Early Diagnosis; early detection; experience; hospital readmission; hospital re-admission; re-admission; re-hospitalization; readmission; rehospitalization; Devices; Reporting; Hypoxemia; hypoxemic; Deterioration; Modeling; Intervention; Intervention Strategies; interventional strategy; Drops; preventing; prevent; ward; Address; Data; Detection; Patient-Focused Outcomes; Patient outcome; Patient-Centered Outcomes; patient oriented outcomes; Small Business Innovation Research Grant; SBIR; Small Business Innovation Research; Monitor; Cardiac; cerebrovascular; cerebral vascular; cerebro-vascular; cost; noninvasive monitor; non-invasive monitor; high risk; clinical care; standard of care; clinical practice; Care giver intervention; caregiver interventions; stratify risk; risk stratification; wearable electronics; wearable system; wearable technology; wearable tool; wearables; wearable device; Cost efficiency; cardiovascular intensive care unit; cardiac intensive care unit; risk of major adverse events; injury to the myocardium; myocardial injury; detection system; detection platform; feasibility testing; Hypotensives; wireless; machine learning model; machine learning based model; machine learning classifier; machine learning based classifier