Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Observational Study
. 2025 Jul 30;25(1):324.
doi: 10.1186/s12893-025-03082-6.

Association between intraoperative lactate levels and acute kidney injury after on-pump cardiac surgery: a retrospective cohort study across two centers

Dong Xu Chen  1   2 , Yu Yang Zhang  3 , Xing Long Xiong  4 , Leng Zhou  3 , Jing Shi  5
Affiliations
Observational Study

Association between intraoperative lactate levels and acute kidney injury after on-pump cardiac surgery: a retrospective cohort study across two centers

Dong Xu Chen et al. BMC Surg. .

Abstract

Background: Hyperlactatemia and acute kidney injury (AKI) represent significant perioperative complications in cardiac surgery. This study investigated their relationship by analyzing multiple lactate parameters during on-pump cardiac procedures.

Methods: In this dual-center retrospective analysis of 5255 cardiac surgery patients, we evaluated the relationship between AKI and four distinct lactate parameters: baseline, mean, peak, and time-weighted average (TWA) concentrations. The association between lactate levels and outcomes was evaluated using restricted cubic spline functions with five knots in our retrospective statistical modeling approach. Concurrently, optimal lactate thresholds were determined through the application of a classification and regression tree algorithm.

Results: Among the 5255 patients analyzed, 931 (17.72%) developed acute kidney injury. Statistical analysis revealed distinct patterns of association between lactate parameters and AKI risk. We identified an L-shaped relationship for mean, peak, and TWA lactate levels, contrasting with a linear association for baseline values. The study established critical thresholds for AKI risk prediction: mean lactate (2.96 mmol/L), peak lactate (4.50 mmol/L), and TWA lactate (2.33 mmol/L). Risk stratification demonstrated that patients in higher lactate quintiles faced substantially increased AKI risk, with odds ratios ranging from 1.34 to 4.37 across different lactate parameters.

Conclusion: These findings established specific lactate thresholds as valuable predictive markers for AKI risk in cardiac surgery, offering clinically applicable parameters for perioperative risk assessment and management. This data supported the implementation of targeted lactate monitoring strategies during cardiac procedures.

Trial registration: The study was registered at www.chictr.org.cn (Registration number: ChiCTR2200057320, Data of Registration: 2022-03-08).

Keywords: Acute kidney injury; Cardiac surgery; Cardiopulmonary bypass; Lactate.

PubMed Disclaimer

Conflict of interest statement

Declarations. Ethics approval and consent to participate: This study was performed in line with the principles of the Declaration of Helsinki. This study, initiated at West China Hospital of Sichuan University in 2022 and later including the Affiliated Hospital of Guizhou Medical University, was approved by the respective Institutional Review Boards (West China Hospital: No. 869–2021; Guizhou Medical University: No. 2022019 K) with informed consent waived. Consent for publication: Not Applicable. Competing interests: The authors declare no competing interests.

Figures

Fig. 1
Fig. 1
Flow chart of participants’ enrollment
Fig. 2
Fig. 2
Association of intraoperative lactate levels with acute kidney injury.A: preoperative (i.e., baseline); B: mean; C: peak; D: time-weighted average Odds ratios are indicated by solid lines and 95% CIs by dashed areas. reference point is lowest value for each of lactate, with five knots placed at 5th, 27.5th, 50th, 72.5th, and 95th centiles of each lactate distribution. Y-axis represents the odds ratio to present AKI for any value of lactate. The reference value was set depending on the restricted cubic splines shape All models were adjusted for cofounders in Table 1
Fig. 3
Fig. 3
Decision tree diagram for acute kidney injury. AKI, acute kidney injury. All models were adjusted for cofounders in Table 1.
See this image and copyright information in PMC

References

    1. Lombardi R, Ferreiro A. Risk factors profile for acute kidney injury after cardiac surgery is different according to the level of baseline renal function. Ren Fail. 2008;30:155–60. - PubMed
    1. Wijeysundera DN, Karkouti K, Beattie WS, Rao V, Ivanov J. Improving the identification of patients at risk of postoperative renal failure after cardiac surgery. Anesthesiology. 2006;104:65–72. - PubMed
    1. Loef BG, Epema AH, Smilde TD, Henning RH, Ebels T, Navis G, et al. Immediate postoperative renal function deterioration in cardiac surgical patients predicts in-hospital mortality and long-term survival. J Am Soc Nephrol. 2005;16:195–200. - PubMed
    1. Chertow GM, Burdick E, Honour M, Bonventre JV, Bates DW. Acute kidney injury, mortality, length of stay, and costs in hospitalized patients. J Am Soc Nephrol. 2005;16:3365–70. - PubMed
    1. Corredor C, Thomson R, Al-Subaie N. Long-term consequences of acute kidney injury after cardiac surgery: a systematic review and meta-analysis. J Cardiothorac Vasc Anesth. 2016;30:69–75. - PubMed

Publication types

LinkOut - more resources