Supplementary Material for: Perioperative Hemodynamic Instability and Fluid Overload are Associated with Increasing Acute Kidney Injury Severity and Worse Outcome after Cardiac Surgery
<p><b><i>Purpose:</i></b> The study aimed to investigate patients'
characteristics, fluid and hemodynamic management, and outcomes
according to the severity of cardiac surgery-associated acute kidney
injury (CSA-AKI). <b><i>Methods:</i></b> In a single-center, prospective
cohort study, we enrolled 282 adult cardiac surgical patients. In a
secondary analysis, we assessed preoperative patients' characteristics,
physiological variables, and medication for intra- and postoperative
fluid and hemodynamic management and outcomes according to CSA-AKI
stages by the Renal risk, Injury, Failure, Loss, End-stage renal disease
(RIFLE) classification. Variables of fluid and hemodynamic management
were further assessed with regard to the need for postoperative renal
replacement therapy (RRT) and in-hospital mortality by the area under
the curve for the receiver operating characteristic (AUC-ROC) and
multivariate regression analysis. <b><i>Results:</i></b> Patients with
worsening RIFLE stage, were significantly older, had lower estimated
glomerular filtration rate and higher body mass index, more peripheral
vascular and chronic obstructive pulmonary disease, atrial fibrillation,
and prolonged duration of cardiopulmonary bypass (all <i>p</i> <
0.01). Patients with more severe AKI stage stayed longer in the
intensive care and hospital, had higher in-hospital mortality, and
requirement for RRT (all <i>p</i> < 0.001). Also, with worsening RIFLE stage, patients had lower intraoperative mean arterial pressure (MAP); <i>p</i> = 0.047, despite higher doses of norepinephrine (<i>p</i>
< 0.001). The intraoperative MAP showed the best discriminatory
ability (AUC-ROC: >0.8) for and was independently associated with RRT
and in-hospital mortality. Moreover, with increasing AKI severity,
patients received significantly more fluid infusion, and required higher
dose of furosemide; nonetheless, they had increased postoperative fluid
balance. <b><i>Conclusions:</i></b> In this cohort, reduced MAP and
increased fluid balance were independently associated with increased
mortality and need for RRT after cardiac surgery.</p
