The Risk Factors, Clinical Prevention And Long-term Outcomes Of Patients With Acute Kidney Injury Following Cardiac Surgery

Objectives:While one-stop hybrid coronary revascularization offers potential benefits in selected patients with multivessel coronary artery disease, the exposure to contrast dye and potent antiplatelet drugs may increase the risk of postoperative acute kidney injury and coagulopathy. The goal of this study was to compare measures of renal function and postoperative bleeding, as well as transfusion requirements in patients undergoing hybrid revascularization compared to off-pump coronary artery bypass grafting (OPCAB).Methods:We retrospectively analyzed 141 consecutive patients undergoing one-stop hybrid coronary revascularization between June 2007 and January 2011.Propensity score matching with 141 off-pump CABG patients from our surgical database was performed for comparison. Change in renal function, cumulative chest tube drainage, and clinical outcome parameters were compared between the two groups. Results:Compared to OPCAB, patients undergoing hybrid revascularization had significantly less chest tube drainage at 12hrs after surgery (p=0.04) as well as total amount during the postoperative period (p<0.001), and required fewer blood transfusions (p=0.001). The hybrid group had a higher incidence of acute kidney injury, but this did not reach statistical significance (25.2% vs 17.6%, p=0.13). The hybrid group required less inotropic and vasoactive support, had fewer respiratory complications, shorter time on mechanical support, and decreased length of ICU stay. Conclusions:Compared with Off-Pump CABG, one-stop hybrid coronary revascularization is associated with benefits such as less postoperative bleeding and blood transfusion requirements without significantly increasing the risk for acute kidney injury.BACKGROUND- In the setting of cardiopulmonary bypass, platelet activation and aggregation may contribute to postoperative ischemic complications involving all major organs. Whereas the role of platelets in acute stroke and myocardial infarction is known, its relation to cardiac surgery-associated acute kidney injury (CSA-AKI) and mortality has not been adequately investigated.OBJECTIVE-This study investigated the association between non-immune mediated decrease in platelet counts and CSA-AKI, and mortality in patients who underwent coronary artery bypass grafting surgery.METHODS-We evaluated 4,201 adult patients who underwent coronary artery bypass graft surgery. Postoperative nadir platelet counts were characterized as the lowest in-hospital values, which were used as a continuous predictor of CSA-AKI and mortality. Also, nadir values in the lowest 10th percentile were used as a categorical predictor. A multivariable logistic regression model examined the association between postoperative platelet counts, AKI and mortality.RESULTS-The median postoperative nadir platelet counts was 121x109/L. The incidence of CSA-AKI was 50%, including 1.6%(34 patients) and 2%(42 patients) experiencing stages Ⅱ and Ⅲ AKI. For every 30x109/L increase in platelet counts, the risk of CSA-AKI decreased by 7%(OR,0.93; 95% CI,0.89-0.98; P= 0.003) and the risk of 30-day mortality decreased by 46%(OR,0.54; 95% CI,0.41-0.69; P< 0.0001). Patients having platelet counts in the lowest 10% were 3.5 times more likely to progress to a higher severity of CSA-AKI (adjusted proportional OR,3.56; 95% CI,2.08 to 5.66; P <0.0001), and had associated increased risks of 30-day (OR,4.34; 95% CI,2.46-7.58; p<0.0001) and long-term (adjusted hazard ratio,1.33; 95% CI,1.12 to 1.59; P=0.001) mortality.CONCLUSIONS-Our findings demonstrated a significant relation between postoperative nadir platelet counts, CSA-AKI, and mortalityBackgroundRisk factors related to cardiac surgery associated acute kidney injury (CSA-AKI) have been identified, including preoperative renal function, ischemia- reperfusion injury, inflammation, oxidant stress, platelet and neutrophil activation, and impaired vasodilation. However, attempts to improve renal outcome after cardiac surgery have had limited success. Preoperative statin use was reported to preserve myocardial function, reduce the risk for atrial fibrillation, and reduce the rate of acute kidney dysfunction in patients with coronary artery disease undergoing cardiac catheterization. However, reported data in cardiac surgery patients are still inconsistent.ObjectivesGiven the mostly retrospective and observational nature of existing data, we conducted a prospective double blind randomized study based on the hypothesis that preoperative loading with atorvastatin would help to reduce the incidence of acute kidney injury in patients undergoing coronary artery bypass grafting (CABG) with cardiac pulmonary bypass (CPB).MethodsThis study was a prospective, double-blinded, randomized clinical trial conducted at the Cardiovascular Institute, Fuwai Hospital, Beijing, China. The study was registered at Clinicaltrials.gov (NCT 01547455), and approved by institutional review board. Patients scheduled for isolated CABG with CPB, statin-naive or discontinuation for 7 days or more, were eligible. Enrolled patients were randomly allocated into two groups, Atorvastatin group patients were received 80mg 12 hours before surgery plus 40mg 2 hours before surgery (total dose of 120mg PO over 12 hours), and placebo group received the same regimen. Blood samples were collected at predefined time points and inflammatory and renal function biomarkers were compared.ResultsAccording to our results, we found that 31.9% patients in the atorvastatin group and 31.1% patients in the placebo group developed acute kidney injury within 48 hours after surgery according to AKIN criteria, P= 1.0. There is no difference of serum creatinine between the two groups, but Atorvastatin had significant lower NGAL than placebo group. Atorvastatin has lower Thl related cytokines, but there is no difference of Th2 related cytokines between the two groups. ConclusionWe found that loading dose atorvastatin in CABG surgery is safe. Atorvastatin can decrease postoperative NGAL but not creatintine, and the inflammatory modulation property may contribute to the potential renal protective effect of Atorvastatin.