Abstract: SA-PO065

Renal Oximetry Measured by Near-Infrared Spectroscopy before Cardiopulmonary Bypass Predicts Cardiac Surgery-Associated AKI

Session Information

Category: Acute Kidney Injury

  • 003 AKI: Clinical and Translational

Authors

  • Joffe, Rachel, Stollery Children''s Hospital, University of Alberta, Edmonton, Alberta, Canada
  • Al aklabi, Mohammed M.s., Stollery Children''s Hospital, Edmonton, Alberta, Canada
  • Bhattacharya, Sudeshna, University of Alberta, Edmonton, Alberta, Canada
  • Cave, Dominic Andrew, Stollery Children''s Hospital, Edmonton, Alberta, Canada
  • Garros, Daniel, Stollery Children''s Hospital, Edmonton, Alberta, Canada
  • Ryerson, Lindsay, University of Alberta, Edmonton, Alberta, Canada
  • Morgan, Catherine, University of Alberta, Edmonton, Alberta, Canada
Background

Cardiac surgery-associated acute kidney injury (CS-AKI) is common in children and associates with negative outcomes. Novel interventions to reduce CS-AKI require knowledge of its pathophysiology. States of altered perfusion, oxygen delivery and energy consumption occur during cardiopulmonary bypass (CPB) and could protect against or contribute to renal cellular injury and recovery. NIRS (near-infrared spectroscopy) is noninvasive technology for monitoring regional blood flow and tissue oxygenation. This study evaluated the relationship between renal regional oxygen saturation (rSO2) and CS-AKI, using NIRS monitoring before, during, and after CPB in children.

Methods

Design, setting, and patients: We conducted a prospective cohort study evaluating children ≤10 kg who underwent CPB (Stollery Children’s Hospital, Edmonton, Alberta, Canada). Heart transplant, preoperative dialysis, sepsis, extracorporeal life support, congenital renal disease, and preoperative nephrotoxins were exclusions.
Measurements: Outcome measure was development of AKI after cardiac surgery (defined according to Kidney Disease: Improving Global Outcomes criteria). rSO2 was measured continuously using NIRS (INVOSTM 5100C Cerebral/Somatic Oximeter, Troy, MI, USA) from time of anesthesia to time of transfer to intensive care.

Results

Main Results: CS-AKI occurred in 65%. Lower baseline (preoperative) rSO2 associated with decreased risk of CS-AKI (p=0.01); children with baseline rSO2 in the highest tertile were 7.14 times more likely to get CS-AKI (vs lowest tertile). Area under the curve for ability of baseline rSO2 to predict CS-AKI was 0.73 (95%CI 0.60 to 0.85). Children with lower baseline glomerular filtration rate had lower mean renal rSO2.

Conclusion

Conclusions: Findings demonstrate that preoperative oxygen supply/demand balance is an important predictor of CS-AKI, suggesting lower preoperative (and intraoperative) renal blood flow may be protective. There is not yet a definite link between remote ischemic preconditioning and prevention of CS-AKI, however renal protective effects of sublethal ischemia should continue to be explored.

Funding

  • Private Foundation Support