Algorithm-based detection of acute kidney injury according to full KDIGO criteria including urine output following cardiac surgery: a descriptive analysis
(2023) 16:12
Schmid et al. BioData Mining
https://doi.org/10.1186/s13040-023-00323-3
RESEARCH
BioData Mining
Open Access
Algorithm‑based detection of acute
kidney injury according to full KDIGO criteria
including urine output following cardiac
surgery: a descriptive analysis
Nico Schmid1, Mihnea Ghinescu2, Moritz Schanz3*, Micha Christ1, Severin Schricker3, Markus Ketteler3,
Mark Dominik Alscher4, Ulrich Franke2 and Nora Goebel2
*Correspondence:
1
Department of Medical
Informatics, Robert Bosch Society
for Medical Research, Stuttgart,
Germany
2
Department of Cardiovascular
Surgery, Robert Bosch Hospital,
Stuttgart, Germany
3
Division of General Internal
Medicine and Nephrology,
Department of Internal Medicine,
Robert Bosch Hospital, Stuttgart,
Germany
4
Executive Chief Physician
of Robert Bosch Hospital
and director of Robert Bosch
Society for Medical Research,
Stuttgart, Germany
Abstract
Background: Automated data analysis and processing has the potential to assist,
improve and guide decision making in medical practice. However, by now it has not
yet been fully integrated in a clinical setting. Herein we present the first results of
applying algorithm-based detection to the diagnosis of postoperative acute kidney
injury (AKI) comprising patient data from a cardiac surgical intensive care unit (ICU).
Methods: First, we generated a well-defined study population of cardiac surgical ICU
patients by implementing an application programming interface (API) to extract, clean
and select relevant data from the archived digital patient management system. Health
records of N = 21,045 adult patients admitted to the ICU following cardiac surgery
between 2012 and 2022 were analyzed. Secondly, we developed a software functionality to detect the incidence of AKI according to Kidney Disease: Improving Global
Outcomes (KDIGO) criteria, including urine output. Incidence, severity, and temporal
evolution of AKI were assessed.
Results: With the use of our automated data analyzing model the overall incidence
of postoperative AKI was 65.4% (N = 13,755). Divided by stages, AKI 2 was the most
frequent maximum disease stage with 30.5% of patients (stage 1 in 17.6%, stage 3 in
17.2%). We observed considerable temporal divergence between first detections and
maximum AKI stages: 51% of patients developed AKI stage 2 or 3 after a previously
identified lower stage. Length of ICU stay was significantly prolonged in AKI patients
(8.8 vs. 6.6 days, p < 0.001) and increased for higher AKI stages up to 10.1 days on average. In terms of AKI criteria, urine output proved to be most relevant, contributing to
detection in 87.3% (N = 12,004) of cases.
Conclusion: The incidence of postoperative AKI following cardiac surgery is strikingly
high with 65.4% when using full KDIGO-criteria including urine output. Automated data
analysis demonstrated reliable early detection of AKI with progressive deterioration of
renal function in the majority of patients, therefore allowing for potential earlier therapeutic intervention for preventing or lessening disease progression, reducing the length
of ICU stay, and ultimately improving overall patient outcomes.
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Schmid et al. BioData Mining
(2023) 16:12
Keywords: Acute kidney injury, Cardiac surgery, Intensive care, Automated detection,
Big data analysis, Algorithm-based detection
Graphical Abstract
Background
The application of tools from modern medical informatics to existing data sets from
routine care is an emerging field in medicine. Promises in this area range from the
improvement in diagnosing conditions with subtle clinical representation to an accurately description of patient populations. Basis for such improvements is the automated extraction and accurate analysis of this data in a privacy-compliant manner [1].
Furthermore, automated data extraction from an existing database can serve as
a solid basis for training machine learning algorithms. These have proven to be an
exceedingly useful tool in the clinical setting over the past years with regards to early
diagnosis, recognizing developing complications and ultimately improving patient
outcomes especially in an intensive care setting [2].
Diagnosis itself is partially subjective and often based on subjective reasoning,
therefore directly dependent on the physician and individual experience. This integrated process will most likely never become fully automated, at least not in the
near future. On the other hand automated data processing can assist the clinician
in arranging, and highlighting the relevant information in a timely manner. Current
efforts are geared toward reducing the physicians’ workload and minimizing human
error [3].
The current project relates to the implementation of a software to automatically
detect AKI according to full KDIGO-criteria including urine output in a postoperative ICU-setting following cardiac surgery.
It’s known that AKI is associated with a high mortality rate up to 60% on ICU and up
to 1 year after discharge, making early detection and prevention crucial [4–7]. In the last
50 years, the mortality of ICU patients on kidney replacing therapy (KRT) has unfortunately not significantly improved and remains very high [8]. Although the incidence of
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AKI is high and associated with worse outcomes, it is often underestimated and frequently under-reported [9]. In addition, reported AKI rates show wide variations as the
diagnosis is often based on serum creatinine values alone as is often seen in studies of
automated AKI detection [10]. However, not considering urine output in the diagnosis
of AKI can significantly underestimate incidence and mortality [11].
Previous studies state that automated AKI detection and prediction can outperform
human predictive performances [3].
In this study, we performed a retrospective descriptive analysis o (...truncated)