Initial Validation of Multi-Frequency Patch-Based Impedance Pneumography in Hospital Settings.

Heart Failure (HF) is a progressive condition that accounts for nearly one million hospitalizations per year in the United States. HF is typified by respiratory distress symptoms that are associated with increased hospitalizations and mortality. Respiratory Rate (RR) and Tidal Volume (TV) are among the respiratory markers that can be used to detect respiratory deteriorations, yet current measurement methods are either inconvenient or unreliable and are only measured sporadically. Wearable Impedance Pneumography (IP) systems capable of continuous monitoring present a unique opportunity to address this gap. In this work we present the design and results of an initial validation study to compare patch-based IP against conventional transthoracic IP in an uncontrolled hospital setting. Muti-frequency IP signals were collected with both configurations on 7 hospitalized patients with HF over two measurement days (admission and discharge). We demonstrated that patch IP captured the same abnormal respiratory patterns as transthoracic IP and detected similar admission-to-discharge trends (direction and magnitude) in respiratory timing markers.