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The development and validation of a novel deep-learning algorithm to predict in-hospital cardiac arrest in ED-ICU (emergency department-based intensive care units): a single center retrospective cohort study

  • Yunseob Shin1
  • Kyung-jae Cho1
  • Mineok Chang1
  • Hyun Youk2
  • Yoon Ji Kim3
  • Ji Yeong Park3
  • Dongjoon Yoo1,4,*,

1VUNO inc., 06541 Seoul, Republic of Korea

2Regional Trauma Center, Wonju Severance Christian Hospital, 26426 Wonju-si, Republic of Korea

3Yonsei University Wonju College of Medicine, 26426 Wonju-si, Republic of Korea

4Department of Critical Care Medicine and Emergency Medicine, Inha University Hospital, 22332 Incheon, Republic of Korea

DOI: 10.22514/sv.2024.045 Vol.20,Issue 4,April 2024 pp.83-98

Submitted: 22 August 2023 Accepted: 28 November 2023

Published: 08 April 2024

*Corresponding Author(s): Dongjoon Yoo E-mail:


Over recent years, the escalation of patient volumes in emergency departments (ED) worldwide has posed to the delivery of timely critical care. Intensive Care Unit (ICU) services became essential due to increasing acuity in EDs, and previous studies revealed a strong association between prolonged boarding times and unfavorable outcomes. Innovative strategies such as Emergency Department-based Intensive Care Units (ED-ICUs) have been introduced to optimize critical care delivery. Given the higher acuity and mortality rates in ED-ICU patients, the prediction of certain events, such as In-Hospital Cardiac Arrest (IHCA), has become abstruse. Conventional Early Warning Scores (EWSs) were developed to stratify the risk of conventional ICUs, but have never been validated in ED-ICU patients with higher acuity. Moreover, EWSs are predominantly focused on forecasting mortality and lack capability for real-time prediction. Our study aimed to develop and validate a deep-learning-based model to predict IHCA within 24 h in ED-ICU. We included 1975 patients admitted to ED-ICU. The study period was from 01 January 2019 to 31 December 2020. Our model, the Deep-ICU CMS (Central Monitoring System), uses four classic vital signs (blood pressure, heart rate, respiratory rate, and body temperature) as input. The model outperformed conventional EWSs in predicting IHCA and maintained performance even with extended prediction windows; it provided robust prediction within a 24-h window, setting it apart from models with restricted prediction horizons. It achieved notably high sensitivity and specificity, overcoming the alarm fatigue issue that is common in EWSs. This study pioneered IHCA risk stratification in ED-ICU and showcases Deep-ICU CMS as a robust prediction tool that overcomes the limitations of conventional EWSs. Prospective and external validation are now warranted to confirm the impact of Deep-ICU CMS in real-world practice. Given the scarcity of research in ED-ICU, our findings contribute valuable insights to optimizing critical care delivery.


In-hospital cardiac arrest (IHCA); Emergency department-based intensive care unit (ED-ICU); Early warning score (EWS); Cardiac arrest (CA) prediction; Clinical deterioration; Machine learning; Deep learning; DeepCars

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Yunseob Shin,Kyung-jae Cho,Mineok Chang,Hyun Youk,Yoon Ji Kim,Ji Yeong Park,Dongjoon Yoo. The development and validation of a novel deep-learning algorithm to predict in-hospital cardiac arrest in ED-ICU (emergency department-based intensive care units): a single center retrospective cohort study. Signa Vitae. 2024. 20(4);83-98.


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