Machine learning predicts mortality based on analysis of ventilation parameters of critically ill patients: multi-centre validation
Authors: Mamandipoor Behrooz , Frutos-Vivar Fernando , Peñuelas Oscar , Rezar Richard , Raymondos Konstantinos , Muriel Alfonso , Du Bin , Thille Arnaud W. , Ríos Fernando , González Marco , del-Sorbo Lorenzo , del Carmen Marín Maria , Pinheiro Bruno Valle , Soares Marco Antonio , Nin Nicolas , Maggiore Salvatore M. , Bersten Andrew , Kelm Malte , Bruno Raphael Romano , Amin Pravin , Cakar Nahit , Suh Gee Young , Abroug Fekri , Jibaja Manuel , Matamis Dimitros , Zeggwagh Amine Ali , Sutherasan Yuda , Anzueto Antonio , Wernly Bernhard , Esteban Andrés , Jung Christian , Osmani Venet 
Published: May 2021

Abstract
Background
Mechanical Ventilation (MV) is a complex and central treatment process in the care of critically ill patients. It influences acid–base balance and can also cause prognostically relevant biotrauma by generating forces and liberating reactive oxygen species, negatively affecting outcomes. In this work we evaluate the use of a Recurrent Neural Network (RNN) modelling to predict outcomes of mechanically ventilated patients, using standard mechanical ventilation parameters.

Methods
We performed our analysis on VENTILA dataset, an observational, prospective, international, multi-centre study, performed to investigate the effect of baseline characteristics and management changes over time on the all-cause mortality rate in mechanically ventilated patients in ICU. Our cohort includes 12,596 adult patients older than 18, associated with 12,755 distinct admissions in ICUs across 37 countries and receiving invasive and non-invasive mechanical ventilation. We carry out four different analysis. Initially we select typical mechanical ventilation parameters and evaluate the machine learning model on both, the overall cohort and a subgroup of patients admitted with respiratory disorders. Furthermore, we carry out sensitivity analysis to evaluate whether inclusion of variables related to the function of other organs, improve the predictive performance of the model for both the overall cohort as well as the subgroup of patients with respiratory disorders.

Results
Predictive performance of RNN-based model was higher with Area Under the Receiver Operating Characteristic (ROC) Curve (AUC) of 0.72 (± 0.01) and Average Precision (AP) of 0.57 (± 0.01) in comparison to RF and LR for the overall patient dataset. Higher predictive performance was recorded in the subgroup of patients admitted with respiratory disorders with AUC of 0.75 (± 0.02) and AP of 0.65 (± 0.03). Inclusion of function of other organs further improved the performance to AUC of 0.79 (± 0.01) and AP 0.68 (± 0.02) for the overall patient dataset and AUC of 0.79 (± 0.01) and AP 0.72 (± 0.02) for the subgroup with respiratory disorders.

Conclusion
The RNN-based model demonstrated better performance than RF and LR in patients in mechanical ventilation and its subgroup admitted with respiratory disorders. Clinical studies are needed to evaluate whether it impacts decision-making and patient outcomes.
Trial registration: NCT02731898 (https://clinicaltrials.gov/ct2/show/NCT02731898), prospectively registered on April 8, 2016.