Adverse renal effects associated with cardiopulmonary bypass

Abstract

Cardiac surgery on cardiopulmonary bypass (CPB) is associated with postoperative renal dysfunction, one of the most common complications of this surgical cohort. Acute kidney injury (AKI) is associated with increased short-term morbidity and mortality and has been the focus of much research. There is increasing recognition of the role of AKI as the key pathophysiological state leading to the disease entities acute and chronic kidney disease (AKD and CKD). In this narrative review, we will consider the epidemiology of renal dysfunction after cardiac surgery on CPB and the clinical manifestations across the spectrum of disease. We will discuss the transition between different states of injury and dysfunction, and, importantly, the relevance to clinicians. The specific facets of kidney injury on extracorporeal circulation will be described and the current evidence evaluated for the use of perfusion-based techniques to reduce the incidence and mitigate the complications of renal dysfunction after cardiac surgery.

Keywords: bypass; cardiac; injury; kidney; surgery.

Figure 1.

Diagnosing renal dysfunction following cardiac surgery. AKI: Acute kidney injury; CKD: Chronic kidney disease; GFR: Glomerular filtration rate; IGFBP7: Insulin growth factor binding protein 7; KDIGO: Kidney disease improving glocal outcomes; RRT: Renal replacement therapy; sCr: Serum creatinine; TIMP-2: Tissue inhibitor of metalloproteinase-2; UO: Urine output.

Figure 2.

Incidence of renal dysfunction states following the cardiac surgery. AKD: Acute kidney disease; AKI: Acute kidney injury; CSA-AKI: Cardiac surgery-associated acute kidney injury; CKD: Chronic kidney disease. Incidence of subclinical CSA-AKI: Meersch 2017, Zarbock 2021. Transition to CSA-AKI: Meersch 2014. Incidence of AKI: Hu 2016. Transition to and incidence of AKD: Matsuura 2020. Transition to CKD: Legouis 2017, Choe 2021, Palomba 2017.

Figure 3.

Pathophysiology of renal dysfunction after cardiac surgery on cardiopulmonary bypass. AR: Autoregulation; DO₂: Oxygen delivery; RBF: Renal blood flow; RPP: Renal perfusion pressure.