Outcome Prediction for Patients with Severe Traumatic Brain Injury Using Permutation Entropy Analysis of Electronic Vital Signs Data

  • Konstantinos Kalpakis
  • Shiming Yang
  • Peter F. Hu
  • Colin F. Mackenzie
  • Lynn G. Stansbury
  • Deborah M. Stein
  • Thomas M. Scalea
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7376)


Permutation entropy is computationally efficient, robust to noise, and effective to measure complexity. We used this technique to quantify the complexity of continuous vital signs recorded from patients with traumatic brain injury (TBI). Using permutation entropy calculated from early vital signs (initial 10~20% of patient hospital stay time), we built classifiers to predict in-hospital mortality, and mobility measured by 3-month Extended Glasgow Outcome Score (GOSE). Sixty patients with severe TBI produced a skewed dataset that we evaluated for accuracy, sensitivity and specificity. With early vital signs data, the overall prediction accuracy achieved 91.67% for mortality, and 76.67% for 3-month GOSE in testing datasets, using the leave-one-out cross validation. We also applied Receiver Operating Characteristic analysis to compare classifiers built from different learning methods. Those results support the applicability of permutation entropy in analyzing the dynamic behavior of biomedical time series for early prediction of mortality and long-term patient outcomes.


Traumatic Brain Injury Vital Sign Cerebral Perfusion Pressure Severe Traumatic Brain Injury Permutation Entropy 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Konstantinos Kalpakis
    • 1
  • Shiming Yang
    • 1
  • Peter F. Hu
    • 2
  • Colin F. Mackenzie
    • 2
  • Lynn G. Stansbury
    • 2
  • Deborah M. Stein
    • 2
  • Thomas M. Scalea
    • 2
  1. 1.Department of Computer Science and Electrical EngineeringUniversity of Maryland, Baltimore CountyBaltimoreUSA
  2. 2.R Adams Cowley Shock Trauma Center; Shock Trauma and Anesthesiology Research CenterUniversity of Maryland School of MedicineBaltimoreUSA

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