Is cortical perfusion a reliable marker for predicting septic acute kidney injury?

Excerpt

With interest, we read the recent publication by Harrois et al. correlating low cortical blood flow with the risk of septic acute kidney injury (SAKI) [1]. SAKI is the most common form of AKI, accounting for almost 50% of cases of AKI [2]. The pathophysiology of SAKI is incompletely understood but comprises ischemia-reperfusion damage, direct inflammatory injury, endothelial cell and microcirculatory dysfunction, and apoptotic changes [3]. It has been a long-held belief that a reduced global renal blood flow (RBF) was the driving force responsible for initiating SAKI though this traditional paradigm has been challenged [3]. Harrois, by using renal contrast-enhanced ultrasound (CEUS), observed an average decrease in cortical renal perfusion (CRPF) during septic shock (N = 20) compared to patients without (N = 10) and an association with SAKI. Closer scrutiny reveals that patients with SAKI trended to higher doses of noradrenaline, lower mean arterial pressure (MAP), and lower cardiac index (CI), without reaching statistical significance. Lactate was significantly higher in SAKI patients. …