We thank Meroni et al.1 for their interest in our article.2 The pathogenesis of cardiac surgery-associated acute kidney injury is complex and multifactorial. The current basic parameter used in the definition of acute kidney injury is oliguria and an increase in serum creatinine, but this often occurs late, when functional kidney injury has already occurred.3 However, early detection of cardiac surgery-associated acute kidney injury is important to establish a diagnosis and treatment.
For this reason, over the past two decades, various predictive models for cardiac surgery-associated acute kidney injury have been developed. The objective of the first and most important of these predictive models was to predict the most serious stages of kidney injury. They were mainly predictive models of dialysis therapy and even mortality associated with cardiac surgery such as those of Chertow et al.,4 Thakar et al.5 and EuroSCORE.6 However, the fact that even a slight increase in creatinine levels in the postoperative period of cardiac surgery are associated with a worsening of patient prognosis has led in recent years to the development of predictive models for cardiac surgery-associated acute kidney injury that complement the prediction of dialysis risk with the prediction of acute kidney injury, mainly based on the kidney disease: improving global outcomes criteria. Thus, authors such as Birnie et al.7 have developed predictive models of acute kidney injury to be applied in preoperative cardiac surgery, and others such as Palomba et al.8 and Jorge-Monjas et al.9 developed predictive models of acute kidney injury to be applied in the ICU, in the immediate postoperative period of cardiac surgery.
But where do we go? The research is now focused on the development of kidney injury biomarkers that precede functional acute kidney injury. They may be also useful for stratifying risk and predicting response to treatment allowing for very early preventive–protective strategies.
Probably in the next decade, predictive models will include several biomarkers among their variables that could improve the predictive capacity of acute kidney injury in both preoperative and postoperative cardiac surgery.
As long as this does not happen, we will continue to investigate the risk factors for the development of cardiac surgery-associated acute kidney injury, especially in those modifiable factors that can be detected in elective, non-urgent cardiac surgery.
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1. Meroni R, Simonini M, Lanzani C, Bignami E. Predictive models for acute kidney injury after cardiac surgery. Eur J Anaesthesiol
2. Echarri G, Duque-Sosa P, Callejas R, et al. External validation of predictive models for acute kidney injury following cardiac surgery. Eur J Anaesthesiol
3. Ho J, Tangri N, Komenda P, et al. Urinary, plasma, and serum biomarkers’ utility for predicting acute kidney injury associated with cardiac surgery in adults: a meta-analysis. Am J Kidney Dis
4. Chertow GM, Lazarus JM, Christiansen CL, et al. Preoperative renal risk stratification. Circulation
5. Thakar CV, Arrigain S, Worley S, et al. A clinical score to predict acute renal failure after cardiac surgery. J Am Soc Nephrol
6. Nashef SA, Roques F, Michel P, et al. European system for cardiac operative risk evaluation (EuroSCORE). Eur J Cardiothorac Surg
7. Birnie K, Verheyden V, Pagano D, et al. Predictive models for kidney disease: improving global outcomes (KDIGO) defined acute kidney injury in UK cardiac surgery. Crit Care
8. Palomba H, De Castro I, Neto AL, et al. Acute kidney injury prediction following elective cardiac surgery: AKICS score. Kidney Int
9. Jorge-Monjas C, Bustamante-Munguira J, Lorenzo M, et al. Predicting cardiac surgery-associated acute kidney injury: the CRATE score. J Crit Care