Kidney Week

Abstract: TH-PO009

Simple Postoperative-AKI Risk (SPARK) Classification in Major Non-Cardiovascular Surgery

Session Information

• AKI: Epidemiology, Risk Factors, Prevention
  October 25, 2018 | Location: Exhibit Hall, San Diego Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Acute Kidney Injury

• 101 AKI: Epidemiology, Risk Factors, and Prevention

Authors

• Park, Sehoon, Seoul National University Hospital, Jongno-gu, Seoul, Korea (the Republic of)

Sehoon Park,

• Cho, Hyunjeong, Chungbuk National University Hospital, Cheongju-si, ChungcheongBuk-Do, Korea (the Republic of)

Hyunjeong Cho,

• Park, Seokwoo, Seoul National University Hospital, Jongno-gu, Seoul, Korea (the Republic of)

Seokwoo Park,

• Lee, Soojin, Seoul national university hospital, Seoul, Korea (the Republic of)

Soojin Lee,

• Kim, Sejoong, Seoul National University Bundang Hospital, Seongnam, Gyeonggi-do, Korea (the Republic of)

Sejoong Kim,

• Kim, Dong Ki, Seoul National University Hospital, Jongno-gu, Seoul, Korea (the Republic of)

Dong Ki Kim,

• Joo, Kwon Wook, Seoul National University Hospital, Jongno-gu, Seoul, Korea (the Republic of)

Kwon Wook Joo,

• Kim, Yon Su, Seoul National University College of Medicine, Seoul, Korea (the Republic of)

Yon Su Kim,

• Lee, Hajeong, Seoul National University College of Medicine, Seoul, Korea (the Republic of)

Hajeong Lee,

Background

We aimed to develop a patient-oriented outcome-based postoperative acute kidney injury (PO-AKI) risk index and classification for planning PO-AKI monitoring before performing major non-cardiac surgery.

Methods

We performed an observational cohort study in two tertiary referral hospitals, each consisting a discovery and validation cohort. Patients who underwent a major non-cardiac operation (≥ 1 hour) were included. We fitted a proportional logistic regression model for an ordinal outcome consisting of the following three categories: no PO-AKI, low-stage AKI, and critical AKI. Critical AKI was defined as KDIGO AKI stage ≥ 2, post-AKI death, or renal failure within 90 days after surgery. PO-AKI events not fulfilling the definition of critical AKI were defined as low-stage AKI.

Results

A total of 50,792 and 39,537 patients were included in the discovery and validation cohorts, respectively. After building a robust model with variables that could be collected or estimated when surgery was scheduled, further simplification was performed. The final Simple PO-AKI RisK (SPARK) index included scores of the following ten variables: age, sex, eGFR, surgery duration, emergency operation, diabetes mellitus, renin-angiotensin-aldosterone system blockades, hypoalbuminemia, anemia, and hyponatremia. The calibration and discrimination results were acceptable. The AUC for low-stage AKI and critical AKI was 0.701 and 0.779 in the validation cohort. When we designated cutoff values to define four classifications, the incidences of the outcomes showed class-dependent increments.

Conclusion

The SPARK index and classification prior to surgery reflects not only the risk of PO-AKI but also the severity and patient-oriented outcomes associated with PO-AKI.