ASN's Mission

To create a world without kidney diseases, the ASN Alliance for Kidney Health elevates care by educating and informing, driving breakthroughs and innovation, and advocating for policies that create transformative changes in kidney medicine throughout the world.

learn more

Contact ASN

1401 H St, NW, Ste 900, Washington, DC 20005

email@asn-online.org

202-640-4660

The Latest on X

Kidney Week

Abstract: FR-OR64

Derivation of a Simple Risk Model for Cardiac Surgery-Associated AKI

Session Information

Category: Acute Kidney Injury

  • 101 AKI: Epidemiology, Risk Factors, and Prevention

Authors

  • Durai, Lavanya, Brigham and Women's Hospital, Boston, Massachusetts, United States
  • Dias, Julie-Alexia, Harvard T H Chan School of Public Health, Boston, Massachusetts, United States
  • Short, Samuel, Brigham and Women's Hospital, Boston, Massachusetts, United States
  • Sabe, Ashraf, Brigham and Women's Hospital, Boston, Massachusetts, United States
  • Redaelli, Simone, Beth Israel Deaconess Medical Center, Boston, Massachusetts, United States
  • Schaefer, Maximilian S., Beth Israel Deaconess Medical Center, Boston, Massachusetts, United States
  • Garcia, Daniela, Beth Israel Deaconess Medical Center, Boston, Massachusetts, United States
  • Khabbaz, Kamal, Beth Israel Deaconess Medical Center, Boston, Massachusetts, United States
  • Shaefi, Shahzad, Beth Israel Deaconess Medical Center, Boston, Massachusetts, United States
  • Leaf, David E., Brigham and Women's Hospital, Boston, Massachusetts, United States
Background

Cardiac surgery-associated acute kidney injury (CSA-AKI) is a frequent postoperative complication. Existing models to predict CSA-AKI have key limitations, including reliance on diagnostic codes, use of noncontemporary data, a focus on AKI requiring dialysis, and inclusion of intra/postoperative variables. Further, most studies are single-centered.

Methods

We collected detailed data from 36,658 adults who underwent cardiac surgery at 3 academic medical centers in Boston, MA, between 2008-2022. Data were derived from the Society for Thoracic Surgeons Database, which includes >1,000 perioperative variables, along with electronic medical records. Candidate predictors included demographics, comorbidities, medications, labs, illness severity, and surgical characteristics, each assessed preoperatively. The primary outcome was CSA-AKI, defined as a ≥100% increase in serum creatinine or dialysis initiation within 5 days following surgery. We used multivariable logistic regression with backward elimination.

Results

A total of 1687 patients (4.6%) developed CSA-AKI. The final model included 15 variables (Fig. 1A). A higher CSA-AKI score monotonically predicted a higher risk of CSA-AKI (Fig. 1B). Patients in the highest risk group had a 33.10-fold higher risk of CSA-AKI than those in the lowest risk group (Fig. 1C). The model had significantly better discrimination for CSA-AKI (AUC 0.75) than previously published models tested in the current cohort, the AUCs for which ranged from 0.64 to 0.69 (P<0.001) (Fig. 1D).

Conclusion

A simple 15-variable risk score predicts CSA-AKI more accurately than previously published models.