Detection of Neonatal Patient Motion Using a Pressure-Sensitive Mat

Patient movements can cause motion artifacts on physiological signals and can result in false alarms in a continuous patient care environment. This paper explores the use of data from a pressure sensitive mat (PSM), placed below neonates in the neonatal intensive care unit (NICU), to detect patient movement. The centre of pressure (COP) is tracked over time using a sliding window. Windows exhibiting large deviations in the COP are indicative of patient motion. Local averaging and window boundary suppression leads to improved movement detection accuracy. Using data from five patients, optimal parameter values were determined using a grid search method. After averaging the best performing parameters, a window size of six seconds was found to be optimal across patients, resulting in an area under the ROC curve of 0.909. Detection accuracy is maintained when evaluated on a patient not used to optimize algorithm parameters, with an accuracy of 93.4%. It is hoped that the movement detection algorithm developed in this work will be useful for gating motion-artifact related false alarms from neonatal patient monitors.