Sensor-Based Upper-Extremity Frailty Assessment for the Vascular Surgery Risk Stratification Federico J. Yanquez, MD, a Anna Peterson, BA, a Craig Weinkauf, MD, PhD, a Kaoru R. Goshima, MD, a Wei Zhou, MD, a Jane Mohler, PhD, b,c,d Hossein Ehsani, PhD, b and Nima Toosizadeh, PhD b,c,d, * a Division of Vascular Surgery, Department of Surgery, University of Arizona, Tucson, Arizona b Department of Biomedical Engineering, University of Arizona, Tucson, Arizona c Department of Medicine, Arizona Center on Aging, University of Arizona, Tucson, Arizona d Division of Geriatrics, General Internal Medicine and Palliative Medicine, Department of Medicine, University of Arizona, Tucson, Arizona article info Article history: Received 18 April 2019 Received in revised form 14 August 2019 Accepted 13 September 2019 Available online xxx Keywords: Upper-limb function Vascular surgery Surgery complication Mortality Wearable sensors Readmission abstract Background: Available methods for determining outcomes in vascular surgery patients are often subjective or not applicable in nonambulatory patients. The purpose of the present study was to assess the association between vascular surgery outcomes and a previously validated upper-extremity function (UEF) method, which incorporates wearable motion sensors for the physical frailty assessment. Materials and methods: Patients (50 y old) undergoing vascular surgery were recruited. Participants performed the 20-s UEF test, which involved rapid elbow flexion. This tech- nology quantifies physical frailty features including slowness, weakness, exhaustion, and flexibility, which allows grouping individuals into nonfrail, prefrail, and frail categories. Surgical outcomes included length of hospital stay, discharged disposition, and 30- d mortality, complications, readmission, and reintervention(s). Associations between outcomes and frailty were assessed using nominal logistic regression models, adjusted for age, gender, body mass index, and wound classification. Results: Thirty-seven participants were recruited: eight nonfrail (age ¼ 62.0  10.6); 22 prefrail (age ¼ 65.6  11.6); and seven frail (age ¼ 68.0  8.0). Significant associations were observed between frailty and length of hospital stay (three times longer among frail par- ticipants, P ¼ 0.03), mortality after surgery (two incidents among frail participants, P < 0.01), and adverse discharge disposition (all nonfrail patients were discharged home, whereas only 43% of frail patients discharged home, P ¼ 0.01). Conclusions: This is the first study to validate the utility of UEF among patients undergoing any vascular surgery. Findings suggest that UEF may provide an objective and simple approach for assessing frailty to predict adverse events after vascular surgery, especially for nonambulatory patients. ª 2019 Elsevier Inc. All rights reserved. * Corresponding author. Department of Biomedical Engineering, Arizona Center on Aging (ACOA), University of Arizona, College of Engineering Bioscience Research Lab (BSRL), 1601 E Helen St., Tucson, AZ 85719. Tel.: þ1 520 621 4369; fax: þ1 520 626 5811. E-mail address: ntoosizadeh@aging.arizona.edu (N. Toosizadeh). Available online at www.sciencedirect.com ScienceDirect journal homepage: www.JournalofSurgicalResearch.com journal of surgical research  - 2019 ( - )1 e8 0022-4804/$ e see front matter ª 2019 Elsevier Inc. All rights reserved. https://doi.org/10.1016/j.jss.2019.09.029