False Ventricular-Fibrillation/Flutter Alarm Reduction of Patient Monitoring Systems in Intensive Care Units

Abstract

Generally in hospitals, false arrhythmia alarm rates are very high in intensive care units (ICUs) patient monitors independent of their brands and prices. These falsely issued alarms disrupt patients’ rest, drain hospital resources, and desensitize the hospital staff to potential emergency situations, which is named as false alarm fatigue. It has been estimated that 43% of life threatening electrocardiogram (ECG) alarms issued by bedside monitors are false, with some categories of alarms being as high as 90%. Ventricular-fibrillation/flutter is the most commonly identified arrhythmia in cardiac arrest patients and it usually ends in death within minutes unless an urgent treatment is not applied. Therefore, in our study, we consider the alarms triggered by ventricular-flutter/fibrillation condition. This type of alarm is usually triggered by ECG and pulsatile waveforms recorded by monitoring equipments, which have standard alarm triggering criteria such as instantaneous thresholds on the predictor values. Most of the ventricular-fibrillation/flutter false alarms are caused by single channel artifacts. In this study, we aim to fuse ECG features with information from other independent signals and get more robust alarm algorithms for ICUs. Pulsatile waveforms, which are highly correlated signals, can be used to corroborate the alarm category and to suppress significant number of false ECG alarms in ICUs. Photoplethysmogram (PPG), arterial blood pressure (ABP) or both PPG and ABP can be used for this purpose. These waveforms are the least noisy pressure signals available in certain ICUs and rarely contain ECG-related artifacts. We implement four different algorithms that use information from ECG, PPG and ABP waveforms, and compare the results. Our best result is 100%/98.1% in terms of sensitivity/specificity based on the Cinc2015 Challenge training dataset.