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: TH-PO020

National AKI Risk Estimates After a Variety of Inpatient Surgeries

Session Information

Category: Acute Kidney Injury

  • 101 AKI: Epidemiology, Risk Factors, and Prevention

Authors

  • Saeed, Mohammed J., Capital Health, Trenton, New Jersey, United States
  • Alhamad, Tarek, Washington University in St. Louis, St. Louis, Missouri, United States
Background

Postoperative acute kidney injury (AKI) is not well studied in non-cardiac procedures. Our aim was to quantify the risk of AKI and dialysis-requiring AKI (AKI-D) after various inpatient surgeries.

Methods

We used the National Inpatient Sample (NIS), which is a nationally representative sample of hospitalizations in the United States and includes records from all payers (including the uninsured). We identified 37 types of surgeries from 1/1/2013 to 9/30/2015 in adults (age ≥18 years) on first 2 days of hospitalization, excluding patients with end stage renal disease. Procedures, AKI and AKI-D were defined using ICD-9-CM diagnosis and procedure codes. Certain same-day surgery combinations were identified as well. Weighted frequencies and proportions of AKI and AKI-D were calculated for each surgery with 95% confidence intervals (CI).

Results

Our study sample of 2,504,894 surgical hospitalizations represented 12,524,470 hospitalizations when weighted. AKI and AKI-D risk was plotted in figure 1 sorted by AKI risk. Surgeries with the highest AKI-D percentages were heart transplant (2.6%, 95% CI 1.0-4.2), liver transplant (3.7%, 95% CI 2.4-4.9) and abdominal aortic aneurysm repair (4.2%, 95% CI 3.4-5.0). Small bowel surgery had the highest AKI risk among bowel surgeries (8.7%, 95% CI 8.3-9.0) and had even higher risk when combined with colon surgery (18.3%, 95% CI 17.4-19.3) or with exploratory laparotomy (14.2%, 95% CI 13.5-14.8). Exploratory laparotomy combined with an abdominal procedure (except gastric and cesarean procedures) had significantly higher AKI risk (range of percentage difference 0.4-5.5).

Conclusion

Using nationally representative data, we estimated the risk of AKI and AKI-D in a large population of surgical hospitalizations including certain same-day surgery combinations.

Figure 1. AKI Risk After Inpatient Surgeries