An automated machine learning-based model predicts postoperative mortality using readily-extractable preoperative
Brian L Hill1, Robert Brown1, Eilon Gabel2
1Department of Computer Science, University of California, Los Angeles, CA, USA.
British Journal of Anaesthesia
|October 20, 2019
Summary
An automated machine learning score accurately predicts in-hospital mortality risk using preoperative data. This new risk score outperforms existing methods, improving patient care and resource allocation in surgery.
Area of Science:
- Medical Informatics
- Machine Learning in Healthcare
- Surgical Risk Stratification
Background:
- Accurate preoperative risk identification is crucial for optimal resource allocation in healthcare.
- Existing risk assessment tools often lack patient-level specificity or require manual chart review.
- The American Society of Anesthesiologists (ASA) physical status classification necessitates clinician chart review.
Purpose of the Study:
- To develop a fully automated score for predicting postoperative in-hospital mortality.
- To utilize machine learning algorithms with structured electronic health record data.
- To compare the performance of the automated score against established risk assessment tools.
Main Methods:
- Employed random forest machine learning algorithms.
- Extracted 58 preoperative features from electronic health records of 53,097 surgical patients.
- Validated the automated score against POSPOM, Charlson comorbidity, and ASA physical status scores.
Main Results:
- The automated score achieved an area under the curve (AUC) of 0.932, outperforming POSPOM (AUC 0.660), Charlson (AUC 0.742), and ASA (AUC 0.866).
- Incorporating ASA physical status with automated features yielded an AUC of 0.936.
- The developed score demonstrated superior predictive accuracy for in-hospital mortality.
Conclusions:
- The automated machine learning score significantly outperforms traditional risk scores in predicting in-hospital mortality.
- This automated tool enhances the precision of preoperative risk assessment.
- Integration with postoperative scores highlights dynamic perioperative risk changes.

