Risk factors of acute kidney injury in elderly patients undergoing coronary artery bypass grafting / 中华全科医师杂志

ABSTRACT

Objective:To analyze the risk factors of acute renal injury (AKI) after coronary artery bypass grafting (CABG) in the elderly patients.Methods:A total of 423 patients aged over 60 years who underwent CABG in Linyi People′s Hospital from May 2014 to May 2010 were retrospectively analyzed. Patients were divided into AKI group and control group according to whether AKI occurred. The risk factors of AKI were analyzed by multivariate logistic regression.Results:Among the 423 patients, 62 cases(14.7%)developed postoperative acute kidney injury. Compared with the patients without AKI ( n=361), the proportions of patients with hypertension, heart function (NYHA) ≥ Ⅲ, atrial fibrillation and cardiopulmonary bypass were higher in AKI group, the proportion of patients using statins before operation was lower [71.0%(44/62) vs. 50.7%(183/361),χ 2 =8.75, P<0.01;38.77%(24/62) vs. 7.5%(27/361),χ 2 =48.67, P<0.01;16.1%(10/62) vs. 4.4%(16/361),χ 2 =12.55, P<0.01;51.6%(32/62) vs. 21.3%(77/361),χ 2 =25.37, P<0.01;59.7%(37/62) vs. 85.6%(309/361),χ 2=23.87, P<0.01]. Patients in AKI group had higher level of blood uric acid, urea nitrogen and creatinine [353.8(275.5, 462.5)μmol/L vs. 314.5(262.9, 383.6)μmol/L, Z=2.75, P=0.01;5.5(4.3, 8.2)mmol/L vs. 5.1(4.3, 6.4)mmol/L, Z=2.44, P＝0.02; 74.9(58.5, 92.7)μmol/L vs. 67.0(57.1, 76.3)μmol/L, Z=2.90, P=0.01];and longer operation time, more blood loss and blood vessel bridge than those in control group [(403.2±124.1) vs. (350.6±110.2), t =3.41, P<0.01;(4.0±0.9) vs. (3.7±0.8), t=2.83, P=0.01;(3.8±0.7) vs. (3.5±0.8), t=3.58, P<0.01]. The multivariate logistic regression analysis showed that preoperative cardiac function (NYHA)≥Ⅲ( OR=8.528,95% CI3.734-19.477, P<0.01),hypertension( OR=6.455,95% CI2.605-15.997, P<0.01),extracorporeal circulation( OR＝3.046,95% CI1.190-7.795, P=0.02),diabetes mellitus( OR=2.294,95% CI1.047-5.026, P=0.04),elevated serum uric acid level( OR=1.004,95% CI1.000-1.008, P=0.03)were the independent risk factors for AKI. Statins is a protective factor for postoperative AKI( OR=0.366,95% CI0.154-0.873, P=0.02). Conclusions:AKI is a common complication after CABG in elderly patients. Cardiac function(NYHA) ≥ Ⅲ,hypertension,extracorporeal circulation,diabetes mellitus,elevated serum uric acid level are risk factors and administration of stating is protective factor for the incidence of acute kidney injury in elderly patients after coronary artery bypass grafting.