Mortality assessment in intensive care units via adverse events using artificial neural networks

  • Authors:
  • Álvaro Silva;Paulo Cortez;Manuel Filipe Santos;Lopes Gomes;José Neves

  • Affiliations:
  • Serviço de Cuidados Intensivos, Hospital Geral de Santo António, Porto, Portugal;Departamento de Sistemas de Informação, Universidade do Minho, Campus de Azurém, 4800-058 Guimarães, Portugal;Departamento de Sistemas de Informação, Universidade do Minho, Campus de Azurém, 4800-058 Guimarães, Portugal;Clínica Médica I, Inst. de Ciências Biomédicas Abel Salazar, Porto, Portugal;Departamento de Informática, Universidade do Minho, Braga, Portugal

  • Venue:
  • Artificial Intelligence in Medicine
  • Year:
  • 2006

Quantified Score

Hi-index 0.00

Visualization

Abstract

Objective: This work presents a novel approach for the prediction of mortality in intensive care units (ICUs) based on the use of adverse events, which are defined from four bedside alarms, and artificial neural networks (ANNs). This approach is compared with two logistic regression (LR) models: the prognostic model used in most of the European ICUs, based on the simplified acute physiology score (SAPS II), and a LR that uses the same input variables of the ANN model. Materials and methods: A large dataset was considered, encompassing forty two ICUs of nine European countries. The recorded features of each patient include the final outcome, the case mix (e.g. age) and the intermediate outcomes, defined as the daily averages of the out of range values of four biometrics (e.g. heart rate). The SAPS II score requires 17 static variables (e.g. serum sodium), which are collected within the first day of the patient's admission. A nonlinear least squares method was used to calibrate the LR models while the ANNs are made up of multilayer perceptrons trained by the RPROP algorithm. A total of 13,164 adult patients were randomly divided into training (66%) and test (33%) sets. The two methods were evaluated in terms of receiver operator characteristic (ROC) curves. Results: The event based models predicted the outcome more accurately than the currently used SAPS II model (P