R. Dorrell3, F. Hsu1, S. Vermillion3, C. Clark2 1Wake Forest University School Of Medicine,Public Health Sciences,Winston Salem, NC, USA 2Wake Forest University School Of Medicine,Department Of Surgery,Winston Salem, NC, USA 3Wake Forest University School Of Medicine,Winston Salem, NC, USA
Introduction:
Early mobilization after major abdominal surgery decreases postoperative complications and length of stay and has become a key component of enhanced recovery pathways. However, patients face substantial barriers to early mobilization and objective measures of patient movement after surgery are limited. Real-time location systems (RTLS) that are typically used for asset tracking provide a novel approach to monitoring in-hospital patterns of movement. Since existing systems were not implemented for tracking dynamic patient movement, the current study investigated the feasibility of using RTLS to objectively track postoperative patient mobilization.
Methods:
The real-time location system used for this study employs a meshed network of infrared and radio frequency identification sensors and detectors that sample device locations nearly every 3s resulting in over 1 million data points per day throughout an academic medical center. RTLS tracking was evaluated systematically in three phases: 1) sensitivity and specificity of the tracking system using simulated patient scenarios, 2) retrospective passive movement analysis of patient-linked equipment (patient IV poles), and 3) prospective observational analysis of patient-attached tracking devices.
Results:
RTLS tracking detected simulated movement in and out of a patient room with sensitivity of 91% and specificity 100%. Specificity decreased to 75% if time out of room was less than 3 minutes. Sensor badge position (chest or wrist) did not change sensitivity or specificity. All tracked patient-linked equipment (bed, IV poles, pumps, etc) were identify for 18 patients following major abdominal operations. Movement of this equipment was retrospectively reviewed and analyzed. For any individual patient, an IV pole may contain 4 tracking badges; therefore, the analysis was limited to a single IV pole tracking badge during the postoperative hospitalization. Median length of stay was 6.7 days with 3386 location data points recorded. Devices remained in the patient's room for mean duration of 684 min (SD 1216 min) per day. Measurable patient movement on the ward was detected for only 2 patients (11%) with 1-8 out-of-room walks per day. 10 patients were prospectively monitored using wrist worn RTLS badges following major abdominal surgery. Patient movement was also recorded using patient diary, direct observation, and pedometer. Sensitivity and specificity of RTLS patient tracking were both 100% in detecting out-of-room ambulation and correlated well with direct observation and patient-reported ambulation.
Conclusion:
Real-time location systems are a novel technology capable of objectively and accurately monitoring patient movement and provides for an innovated approach to promoting early mobilization after major abdominal surgery.