Abstract 13147: Monitoring Central Arterial Pressure on the Chest Surface: Initial Results From Two Pilot Studies in Human Subjects

Abstract

Central arterial pressure (AP) monitoring is essential for personalized patient management but requires direct arterial line (Aline) access. We report the first results from two pilot studies tracking central AP in humans using a noninvasive, high-fidelity MEMS array (APEX, PinMed, Inc., Pittsburgh, PA) versus an Aline ( Study 1 ) and a brachial cuff ( Study 2 ). Methods: The APEX array was designed and optimized for the chest surface using a realistic, full-scale physical model (Fig. 1A) and a validated, large-scale computational model of circulation. Study 1: AP was recorded in 7 CVICU patients (age: 73±7y, 43% female; pressure ranges for systolic, diastolic, and mean: 91-198, 46-83, and 61-121 mm Hg, respectively). Study 2: AP was recorded during moderate physical activity (handgrip followed by leg lifts) in 30 subjects (age: 46±10y, 53% female; pressure ranges for systolic, diastolic, and mean: 90-210, 49-116, and 67-147 mm Hg, respectively). Results: Study 1: AP was recorded over 2.7±1.7hr with no adverse events. Individual changes in AP recorded by APEX and Aline were similar (mean pressure [MP] range for individual changes >10 mm; Fig. 1B, r: 0.4-0.8); the differences were small (RMSE for MP: 4.8 mm, r 2 : 0.93, Fig. 1C). Study 2: Individual AP changes recorded by APEX and brachial cuff were similar (Fig. 2A). The accuracy was similar for the entire group (N=30) and for the subgroup of subjects with high BMI (n=15); there were no significant differences between the subgroups of female and male subjects (Fig. 2B, 2C). Conclusions: If confirmed in larger studies, the surface MEMS array has the potential to enable noninvasive central-AP monitoring in clinical and ambulatory settings.