Automatic Classification of Sedation Levels in ICU Patients Using Heart Rate Variability
- 1 September 2016
- journal article
- research article
- Published by Ovid Technologies (Wolters Kluwer Health) in Critical Care Medicine
- Vol. 44 (9), e782-e789
- https://doi.org/10.1097/ccm.0000000000001708
Abstract
Objective: To explore the potential value of heart rate variability features for automated monitoring of sedation levels in mechanically ventilated ICU patients. Design: Multicenter, pilot study. Setting: Several ICUs at Massachusetts General Hospital, Boston, MA. Patients: Electrocardiogram recordings from 40 mechanically ventilated adult patients receiving sedatives in an ICU setting were used to develop and test the proposed automated system. Measurements and Main Results: Richmond Agitation-Sedation Scale scores were acquired prospectively to assess patient sedation levels and were used as ground truth. Richmond Agitation-Sedation Scale scores were grouped into four levels, denoted “unarousable” (Richmond Agitation- Sedation Scale = –5, –4), “sedated” (–3, –2, –1), “awake” (0), “agitated” (+1, +2, +3, +4). A multiclass support vector machine algorithm was used for classification. Classifier training and performance evaluations were carried out using leave-oneout cross validation. An overall accuracy of 69% was achieved for discriminating between the four levels of sedation. The proposed system was able to reliably discriminate (accuracy = 79%) between sedated (Richmond Agitation-Sedation Scale < 0) and nonsedated states (Richmond Agitation-Sedation Scale > 0). Conclusions: With further refinement, the methodology reported herein could lead to a fully automated system for depth of sedation monitoring. By enabling monitoring to be continuous, such technology may help clinical staff to monitor sedation levels more effectively and to reduce complications related to over- and undersedation.Keywords
This publication has 39 references indexed in Scilit:
- Autonomic Nervous System Function and Depth of Sedation in Adults Receiving Mechanical VentilationAmerican Journal of Critical Care, 2009
- Comparison of Electrophysiologic Monitors With Clinical Assessment of Level of SedationMayo Clinic Proceedings, 2006
- Dysautonomia and heart rate variability following severe traumatic brain injuryBrain Injury, 2006
- The Different Effects of Intravenous Propofol and Midazolam Sedation on Hemodynamic and Heart Rate VariabilityAnesthesia & Analgesia, 2005
- Assessment of postoperative sedation level with spectral EEG parametersClinical Neurophysiology, 2002
- A comparison of methods for multiclass support vector machinesIEEE Transactions on Neural Networks, 2002
- Autonomic dysfunction in the ICU patientCurrent Opinion in Critical Care, 2001
- An overview of statistical learning theoryIEEE Transactions on Neural Networks, 1999
- Mechanisms whereby Propofol Mediates Peripheral Vasolidation in HumansAnesthesiology, 1997
- Support-vector networksMachine Learning, 1995