Acute kidney injury (AKI) occurs in 5%–42% of patients undergoing cardiac surgery, making it one of the most common peri-operative complications in this patient population (1). Even subtle declines in postoperative kidney function confer an increased risk of postoperative mortality and persistent kidney injury (2, 3).
The Society of Thoracic Surgeons (STS), Society of Cardiovascular Anesthesiologists (SCA), and American Society of Extracorporeal Technology (AmSECT) recently published their consensus Clinical Practice Guidelines for the Prevention of Adult Cardiac Surgery-Associated Acute Kidney Injury (4). This is a pragmatic guideline with seven recommendations (Table 1).
Summary of recommendations from the 2023 STS/SCA/AmSECT Clinical Practice Guidelines for the Prevention of Adult Cardiac Surgery-Associated Acute Kidney Injury
The new cardiac surgery-associated (CSA)-AKI guidelines reinforce standard cardiac surgical practices for most institutions. For example, avoidance of hyperthermic perfusion (>37°C) remains a class I recommendation to prevent cerebral hyperthermia. Elements of the Kidney Disease: Improving Global Outcomes (KDIGO) bundle, such as peri-operative discontinuation of angiotensin-converting enzyme inhibitors and angiotensin-receptor blockers, avoiding hyperglycemia, and close hemodynamic monitoring, are already part of existing guidelines to avoid hypotension and infection and to optimize systemic perfusion. The use of minimally invasive extracorporeal circulation is currently a class IIA recommendation to reduce blood loss and transfusion.
Select recommendations continue to evolve and expand on prior recommendations. Notably, the new CSA-AKI guidelines officially recommend against using dopamine and mannitol for adult cardiac surgery patients. Furthermore, although prior guidelines have recommended adjusting the pump flow rate during cardiopulmonary bypass (CPB) based on oxygenation and metabolic parameters, the new CSA-AKI guidelines specify the use of goal-directed perfusion targeting oxygen delivery (DO2) ≥270 mL/min/m2 as a class I recommendation.
The one element in the new CSA-AKI guidelines that may deviate from current practices is its recommendation that fenoldopam may be used to reduce the risk of CSA-AKI as long as hypotension can be avoided (class IIB). The literature supporting this recommendation is conflicting. A prospective randomized clinical trial looking at attenuating immediate postoperative AKI showed no benefit and significantly more hypotension (5). It is also acknowledged by the authors of the new guidelines that KDIGO does not support using fenoldopam to prevent or treat AKI. Therefore, we would hesitate to adopt the use of fenoldopam to reduce the risk of CSA-AKI without more substantive evidence to support its use in this patient population.
The new CSA-AKI guidelines affirm existing clinical practices for the care of adult cardiac surgery patients. They also highlight the need for continued research for novel ways to reduce the incidence of CSA-AKI, as it remains a significant source of morbidity and mortality in patients undergoing cardiac surgery.
References
- 1. ↑
Wang Y, Bellomo R. Cardiac surgery-associated acute kidney injury: Risk factors, pathophysiology and treatment. Nat Rev Nephrol 2017; 13:697–711. doi: 10.1038/nrneph.2017.119
- 2. ↑
Priyanka P, et al. The impact of acute kidney injury by serum creatinine or urine output criteria on major adverse kidney events in cardiac surgery patients. J Thorac Cardiovasc Surg 2021; 162:143–151. doi: 10.1016/j.jtcvs.2019.11.137
- 3. ↑
Liotta M, et al. Minimal changes in postoperative creatinine values and early and late mortality and cardiovascular events after coronary artery bypass grafting. Am J Cardiol 2014; 113:70–75. doi: 10.1016/j.amjcard.2013.09.012
- 4. ↑
Brown JR, et al. The Society of Thoracic Surgeons/Society of Cardiovascular Anesthesiologists/American Society of Extracorporeal Technology Clinical Practice Guidelines for the Prevention of Adult Cardiac Surgery-Associated Acute Kidney Injury. Ann Thorac Surg 2023; 115:34–42. doi: 10.1016/j.athoracsur.2022.06.054
- 5. ↑
Bove T, et al. Effect of fenoldopam on use of renal replacement therapy among patients with acute kidney injury after cardiac surgery: A randomized clinical trial. JAMA 2014; 312:2244–2253. doi: 10.1001/jama.2014.13573