Nav: Home

ICU risk scores perform well as 'continuous markers' of illness severity

February 26, 2018

February 26, 2018 - Commonly used ICU risk scores can be "repurposed" as continuous markers of severity of illness in critically ill patients--providing ongoing updates on changes in the patient's condition and risk of death, according to a study in the March issue of Critical Care Medicine, official journal of the Society of Critical Care Medicine (SCCM). The journal is published by Wolters Kluwer.

Three ICU risk scores, designed for different purposes, "performed reasonably well as a marker of severity of illness at admission, as well as throughout the ICU stay, demonstrating that it is possible for risk models to perform well even when deployed for uses other than originally intended," write Omar Badawi, PharmD, MPH, FCCM, and colleagues of Philips Healthcare, Baltimore. The study illustrates how the use of "Big Data" can advance our understanding of critically ill patients, drawing on extensive data contributed by tele-ICU programs across the United States.

One of Three ICU Risk Models Performs Best in Predicting Mortality

The study used data from the Philips eICU Research Institute database, which assembles clinical data from a diverse mix of hospitals using tele-ICU software. The analysis included de-identified data on more than 560,000 ICU patient stays, contributed by 333 ICUs at 208 US hospitals. The data covered nearly 39 million patient-hours of ICU care.

The analysis transformed three widely used ICU risk scores--designed to be assessed for different clinical scenarios--into continuous risk markers:
  • Acute Physiology and Chronic Health Evaluation IV (APACHE): Perhaps the best-known ICU risk score, originally designed to estimate the risk of death on admission to the ICU.
  • Sequential Organ Failure Assessment (SOFA): Originally designed to assess organ failure risk in patients with sepsis, the SOFA score was later validated for assessment every 48 hours to assess mortality risk.
  • Discharge Readiness Score (DRS): Designed to assist ICU discharge decisions by estimating the risk of death in the first 48 hours after the patient leaves the ICU.
Hourly values for all three scores were evaluated as predictors of mortality risk. Overall, 4.8 percent of patients died in the ICU.

As continuous markers, all three models showed good accuracy in predicting the risk of death in the ICU, as well as risk of death within 24 hours. Of the three scores, the DRS had the highest predictive value. For patients in the highest ten percent of risk based on average score, the percentage who died was 30.4 percent with APACHE (average score > 80.0), 26.5 percent with SOFA (average score >7.6), and 36.4 percent with DRS (average score >13.0). The results were similar on analysis of hospitals with larger numbers of patients and deaths.

Looking closely at trends in each score during the ICU stay provided insights into the differences between the three models. Even in survivors, APACHE and SOFA scores tended to increase throughout the first 24 hours in the ICU. In contrast, the DRS decreased during the first 24 hours for survivors. That suggests that the DRS was more responsive to changes in patient condition--especially improvements.

The authors hypothesize that these differences may be attributed to model design. Both APACHE and SOFA primarily rely on the "worst" values of the preceding 24 hours to calculate a score. In contrast, DRS relies primarily on summary measures of the preceding 24 hours, such as averages and coefficient of variation.

Those observations highlight the need to be aware of differences in model design, and how the predictions may vary across ICU settings and in patients with varying characteristics. To help ICU clinicians understand these differences, Dr. Badawi and colleagues have created an online interactive data visualization tool.

"These findings suggest that it is possible to repurpose risk models for use outside of their original design, but with caveats," Dr. Badawi and coauthors conclude. They emphasize the need for further studies to determine the clinical relevance of continuous severity of illness indicators, and the need for caution when introducing these models in differing ICU settings. Dr. Badawi added, "Risk models provide objective data regarding patient status but users must combine their clinical judgment with an understanding of the model design in order to interpret the score for specific patients."

Click here to read "Evaluation of ICU Risk Models Adapted for Use as Continuous Markers of Severity of Illness Throughout the ICU Stay."

DOI: 10.1097/CCM.0000000000002904
-end-
Note to editors: For further information, contact Curtis Powell, Director of Marketing and Communications for SCCM: phone +1 (847) 827-7282 or +1 (312) 285-6551; or email cpowell@sccm.org.

About the Society of Critical Care Medicine

The Society of Critical Care Medicine (SCCM) is the largest nonprofit medical organization dedicated to promoting excellence and consistency in the practice of critical care. With members in more than 100 countries, SCCM is the only organization that represents all professional components of the critical care team. The Society offers a variety of activities that ensures excellence in patient care, education, research and advocacy. SCCM's mission is to secure the highest quality care for all critically ill and injured patients. Visit http://www.sccm.org for more information. Follow @SCCM or visit us on Facebook.

About Critical Care Medicine

Critical Care Medicine is the premier peer-reviewed, scientific publication in critical care medicine. Directed to those specialists who treat patients in the intensive care unit and critical care unit, including chest physicians, surgeons, pediatricians, pharmacists/pharmacologists, anesthesiologists, critical care nurses and other healthcare professionals, Critical Care Medicine covers all aspects of acute and emergency care for the critically ill or injured patient. Each issue presents critical care practitioners with clinical breakthroughs that lead to better patient care, the latest news on promising research and advances in equipment and techniques. Follow @CritCare Med.

About Wolters Kluwer

Wolters Kluwer N.V. (AEX: WKL) is a global leader in information services and solutions for professionals in the health, tax and accounting, risk and compliance, finance and legal sectors. We help our customers make critical decisions every day by providing expert solutions that combine deep domain knowledge with specialized technology and services.

Wolters Kluwer reported 2016 annual revenues of €4.3 billion. The company, headquartered in Alphen aan den Rijn, the Netherlands, serves customers in over 180 countries, maintains operations in over 40 countries and employs 19,000 people worldwide.

Wolters Kluwer Health is a leading global provider of information and point of care solutions for the healthcare industry. For more information about our products and the organization, visit http://www.wolterskluwer.com/, follow @WKHealth or @Wolters_Kluwer on Twitter, like us on Facebook, follow us on LinkedIn, or follow WoltersKluwerComms on YouTube.

Wolters Kluwer Health

Related Data Articles:

Storing data in music
Researchers at ETH Zurich have developed a technique for embedding data in music and transmitting it to a smartphone.
Life data economics: calling for new models to assess the value of human data
After the collapse of the blockchain bubble a number of research organisations are developing platforms to enable individual ownership of life data and establish the data valuation and pricing models.
Geoscience data group urges all scientific disciplines to make data open and accessible
Institutions, science funders, data repositories, publishers, researchers and scientific societies from all scientific disciplines must work together to ensure all scientific data are easy to find, access and use, according to a new commentary in Nature by members of the Enabling FAIR Data Steering Committee.
Democratizing data science
MIT researchers are hoping to advance the democratization of data science with a new tool for nonstatisticians that automatically generates models for analyzing raw data.
Getting the most out of atmospheric data analysis
An international team including researchers from Kanazawa University used a new approach to analyze an atmospheric data set spanning 18 years for the investigation of new-particle formation.
Ecologists ask: Should we be more transparent with data?
In a new Ecological Applications article, authors Stephen M. Powers and Stephanie E.
Should you share data of threatened species?
Scientists and conservationists have continually called for location data to be turned off in wildlife photos and publications to help preserve species but new research suggests there could be more to be gained by sharing a rare find, rather than obscuring it, in certain circumstances.
Using light for next-generation data storage
Tiny, nano-sized crystals of salt encoded with data using light from a laser could be the next data storage technology of choice, following research by Australian scientists.
Futuristic data storage
The development of high-density data storage devices requires the highest possible density of elements in an array made up of individual nanomagnets.
Making data matter
The advent of 3-D printing has made it possible to take imaging data and print it into physical representations, but the process of doing so has been prohibitively time-intensive and costly.
More Data News and Data Current Events

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Rethinking Anger
Anger is universal and complex: it can be quiet, festering, justified, vengeful, and destructive. This hour, TED speakers explore the many sides of anger, why we need it, and who's allowed to feel it. Guests include psychologists Ryan Martin and Russell Kolts, writer Soraya Chemaly, former talk radio host Lisa Fritsch, and business professor Dan Moshavi.
Now Playing: Science for the People

#538 Nobels and Astrophysics
This week we start with this year's physics Nobel Prize awarded to Jim Peebles, Michel Mayor, and Didier Queloz and finish with a discussion of the Nobel Prizes as a way to award and highlight important science. Are they still relevant? When science breakthroughs are built on the backs of hundreds -- and sometimes thousands -- of people's hard work, how do you pick just three to highlight? Join host Rachelle Saunders and astrophysicist, author, and science communicator Ethan Siegel for their chat about astrophysics and Nobel Prizes.