Acute kidney injury (AKI) is a severe clinical complication with increasing incidence  and it is associated with adverse short- and long-term outcomes resulting in a major health care burden worldwide. [2,3] Recent reports on incidences of AKI indicate that every second surgical patient is affected by this complication, although the true epidemiology of surgical induced AKI still remains elusive.
Since AKI is now being considered as an independent risk factor for adverse outcomes [4-7], more detailed knowledge of its occurrence is needed to enhance the awareness for this critical condition and to improve patient management as well as the outcome.
With the introduction of consensus classification systems (Risk Injury Failure Loss and End-stage (RIFLE) , Acute Kidney Injury Network (AKIN) , and the Kidney Disease: Improving Global Outcomes (KDIGO) criteria ), the awareness for its importance has grown tremendously and most AKI studies use these definitions to report case numbers.
The establishment of an accurate occurrence rate for AKI is important for health policy, quality initiatives as well as for designing clinical trials. However, analysing AKI from existing databases in the surgical setting is often limited by missing data elements needed for the application of these definitions, especially the inclusion of the urine output criteria. Additionally, administrative databases are limited since billing codes do not capture many cases of AKI.  This might be one explanation for the large variation in occurrence rates of AKI reported in the surgical setting.
Since the introduction of the different classification systems, results were thought to become comparable. Most of the trials, though, are retrospective and therefore limited due to the nature of the trial design. Additionally, AKI is mainly diagnosed by the serum creatinine criterion thereby disregarding urine output. However, it has been recently shown in a general ICU patient cohort that the urine criterion is important for diagnosing and staging AKI.  All these aspects result in a large variation of reported incidences.
For instance, after abdominal surgery, the occurrence rate of AKI ranges from 1.8-39.3%. [13,14] Recent studies on the incidence of AKI after cardiac surgery demonstrate a range in the AKI incidence from 3.1% to 25.6% [15,16]. Hoste et al., though, recently performed a large prospective observational multinational trial including 1802 critically ill (surgical as well as non-surgical) patients in 139 ICUs worldwide to evaluate the epidemiology of AKI. Focusing on surgical patients (n=740), the incidence of AKI according to the KDIGO criteria was 53.2% indicating a considerably higher occurrence when using the latest consensus definition and a standardised data collection instrument.  Consequently, the exact incidence of AKI after extended surgical procedures is currently unknown.
The objective of the Epidemiology of Surgical-induced Acute Kidney Injury (EPIS-AKI) trial is to prospectively evaluate the epidemiology of AKI after extended surgical procedures in hospitals using the latest consensus definition for AKI and a standardised data collection instrument and to assess the dependence of AKI on preoperative and intraoperative factors. EPIS-AKI is a prospective international multi-centre observational study. We seek to include patients undergoing major surgery for at least 2 hours and who are admitted to an observational unit such as intensive care unit or high dependency unit to adequately address both criteria of the KDIGO definition since the assessment of urine output requires a Foley catheter. Based on the high number of included patients, we will use the data to generate new risk scores for surgical patients and for different surgical subpopulations.
To accomplish the aim of 10,000 included patients within a short time period we kindly ask for support within the members of the European Society of Anaesthesiology. AKI has a high impact on health policy and the results are urgently needed for designing new pre-emptive and therapeutic trials, which is also the main goal of the RAPNet (Renal Protective Network, Initiator: Univ.-Prof. Dr. med. Alexander Zarbock). Both EPIS-AKI and RAPNet are supported by the European Society of Anaesthesiology. Moreover, with EPIS-AKI we hope to build up a common spirit to enhance the scientific exchange within the growing RAPNet network. The study also provides the momentum for boosting teamwork which may allow fruitful cooperation for future investigations.
AKI, acute kidney injury; ICU, intensive care unit; IMC, intermediate care unit; MAKE90, major adverse kidney events at day 90; PACU, Postanesthesia care unit.
- Wald R, McArthur E, Adhikari NK, et al. Changing incidence and outcomes following dialysis-requiring acute kidney injury among critically ill adults: a population-based cohort study. American journal of kidney diseases: the official journal of the National Kidney Foundation. Jun 2015;65(6):870-877.
- Lameire NH, Bagga A, Cruz D, et al. Acute kidney injury: an increasing global concern. Lancet. Jul 13 2013;382(9887):170-179.
- Siew ED, Davenport A. The growth of acute kidney injury: a rising tide or just closer attention to detail? Kidney international. Jan 2015;87(1):46-61.
- Bellomo R, Kellum JA, Ronco C. Acute kidney injury. Lancet. Aug 25 2012;380(9843):756-766.
- Hoste EA, Schurgers M. Epidemiology of acute kidney injury: how big is the problem? Critical care medicine. Apr 2008;36(4 Suppl):S146-151.
- Chawla LS, Eggers PW, Star RA, Kimmel PL. Acute kidney injury and chronic kidney disease as interconnected syndromes. The New England journal of medicine. Jul 3 2014;371(1):58-66.
- Murugan R, Kellum JA. Acute kidney injury: what’s the prognosis? Nature reviews. Nephrology. Apr 2011;7(4):209-217.
- Bellomo R, Ronco C, Kellum JA, Mehta RL, Palevsky P, Acute Dialysis Quality Initiative w. Acute renal failure – definition, outcome measures, animal models, fluid therapy and information technology needs: the Second International Consensus Conference of the Acute Dialysis Quality Initiative (ADQI) Group. Critical care. Aug 2004;8(4):R204-212.
- Mehta RL, Kellum JA, Shah SV, et al. Acute Kidney Injury Network: report of an initiative to improve outcomes in acute kidney injury. Critical care. 2007;11(2):R31.
- KDIGO Aw. KDIGO clinical practice guideline for acute kidney injury. Kidney Int Suppl. 2012;2:1-138.
- Grams ME, Waikar SS, MacMahon B, Whelton S, Ballew SH, Coresh J. Performance and limitations of administrative data in the identification of AKI. Clinical journal of the American Society of Nephrology: CJASN. Apr 2014;9(4):682-689.
- Kellum JA, Sileanu FE, Murugan R, Lucko N, Shaw AD, Clermont G. Classifying AKI by Urine Output versus Serum Creatinine Level. Journal of the American Society of Nephrology: JASN. Sep 2015;26(9):2231-2238.
- Cho E, Kim SC, Kim MG, Jo SK, Cho WY, Kim HK. The incidence and risk factors of acute kidney injury after hepatobiliary surgery: a prospective observational study. BMC nephrology. Oct 23 2014;15:169.
- Bihorac A, Yavas S, Subbiah S, et al. Long-term risk of mortality and acute kidney injury during hospitalization after major surgery. Annals of surgery. May 2009;249(5):851-858.
- Kim JY, Joung KW, Kim KM, et al. Relationship between a perioperative intravenous fluid administration strategy and acute kidney injury following off-pump coronary artery bypass surgery: an observational study. Critical care. 2015;19:350.
- Seelhammer TG, Maile MD, Heung M, Haft JW, Jewell ES, Engoren M. Kinetic estimated glomerular filtration rate and acute kidney injury in cardiac surgery patients. Journal of critical care. Feb 2016;31(1):249-254.
- Hoste EA, Bagshaw SM, Bellomo R, et al. Epidemiology of acute kidney injury in critically ill patients: the multinational AKI-EPI study. Intensive care medicine. Aug 2015;41(8):1411-1423.
More Newsletter Articles
Visit our Euroanaesthesia 2020 Website for more news on everything related to the virtual congress.
Visit our COVID-19 Resource Hub for other news and resources.