Mortality and costs associated with acute kidney injury following major elective, non-cardiac surgery

W Brenton French; Pranav R Shah; Yahya I Fatani; Megan M Rashid; Spencer T Liebman; Brian J Cocchiola; Kenneth F Potter; Salem Rustom; Michael J Scott

doi:10.1016/j.jclinane.2022.110933

Mortality and costs associated with acute kidney injury following major elective, non-cardiac surgery

J Clin Anesth. 2022 Nov:82:110933. doi: 10.1016/j.jclinane.2022.110933. Epub 2022 Aug 4.

Authors

W Brenton French¹, Pranav R Shah², Yahya I Fatani³, Megan M Rashid², Spencer T Liebman², Brian J Cocchiola², Kenneth F Potter², Salem Rustom⁴, Michael J Scott⁵

Affiliations

¹ Department of Surgery, Virginia Commonwealth University Health System, Richmond, VA, USA.
² Department of Anesthesiology, Virginia Commonwealth University Health System, Richmond, VA, USA.
³ Division of Nephrology, Department of Medicine, Virginia Commonwealth University Health System, Richmond, VA, USA.
⁴ Department of Biostatistics, Virginia Commonwealth University, Richmond, VA, USA.
⁵ Department of Anesthesiology, Virginia Commonwealth University Health System, Richmond, VA, USA; Department of Anesthesiology and Critical Care Medicine, University of Pennsylvania, Philadelphia, PA, USA. Electronic address: Michael.Scott@Pennmedicine.Upenn.edu.

PMID: 35933842
DOI: 10.1016/j.jclinane.2022.110933

Abstract

Objective: This study evaluated postoperative AKI severity and its relation to short- and long-term patient outcomes.

Design: A retrospective, single-center cohort study of patients undergoing surgery from January 2015 to May 2020.

Setting: An urban, academic medical center.

Patients: Adult patients undergoing elective, non-cardiac surgery at our institution with a postoperative length of stay (LOS) of at least 24 h were included. Patients were included in 1-year mortality analysis if their procedure occurred prior to June 2019.

Interventions: None.

Measurements: Postoperative AKI was identified and staged using the Kidney Disease Improving Global Outcomes definitions. The outcomes analyzed were in-hospital mortality, LOS, total cost of the surgical hospitalization, and 1-year mortality.

Main results: Of the 8887 patients studied, 648 (7.3%) had postoperative AKI. AKI was associated with severity-dependent increases in all outcomes studied. Patients with AKI had rates of in-hospital mortality of 2.0%, 3.8%, and 12.5% for stage 1, 2, and 3 AKI compared to 0.3% for patients without AKI. Mean total costs of the surgical hospitalization were $23,896 (SD $23,736) for patients without AKI compared to $33,042 (SD $27,115), $39,133 (SD $34,006), and $73,216 ($82,290) for patients with stage 1, 2, and 3 AKI, respectively. In the 6729 patients who met inclusion for 1-year mortality analysis, AKI was also associated with 1-year mortality rates of 13.9%, 19.4%, and 22.7% compared to 5.2% for patients without AKI. In multivariate models, stage 1 AKI patients still had a higher probability of 1-year mortality (OR 1.9, 95% CI 1.3-2.6, p < 0.001) in addition to $4391 of additional costs when compared to patients without AKI (95% CI $2498-$6285, p < 0.001).

Conclusions: All stages of postoperative AKI were associated with increased LOS, surgical hospitalization costs, in-hospital mortality, and 1-year mortality. These findings suggest that patients with even a low-grade or stage 1 AKI are at higher risk for short- and long-term complications.

Keywords: Acute kidney injury; Costs; Mortality; Outcomes; Surgery.

MeSH terms

Acute Kidney Injury* / etiology
Adult
Cohort Studies
Hospital Mortality
Humans
Postoperative Complications* / etiology
Retrospective Studies
Risk Factors