Risk factors for continuous renal replacement therapy after surgical repair of type A aortic dissection

To identify the risk factors for continuous renal replacement therapy (CRRT) following surgical repair of type A aortic dissection (TAAD) using the total arch replacement and frozen elephant trunk (TAR + FET) technique.

The study included 330 patients with TAAD repaired using TAR + FET between January 2014 and April 2015. Mean age was 47.1±10.2 years (range, 18-73 years) and 242 were male (73.3%). Univariate and multivariate analyses were used to identify the risk factors for CRRT.

Postoperative CRRT was required in 38 patients (mean age 50.7±10.0 years; 27 males). Operative death occurred in 12 patients (3.6%, 12/330). The mortality rate was 23.7% (9/38) in patients with CRRT and 1.0% (3/292) in those without CRRT (P<0.001). Factors associated with CRRT were age (50.7±10.0 vs. 46.7±10.2 years, P=0.023), preoperative serum creatinine (sCr) (135.0±154.2 vs. 85.7±37.0 µmol/L, P<0.001), emergency operation (89.5% vs. 73.3%, P=0.030), cardiopulmonary bypass (CPB) time (265.2±98.8 vs. 199.7±44.2 minutes, P<0.001), cross-clamp time (144.6±54.8 vs. 116.3±33.2 minutes, P<0.001), the amount of red blood cell (8.0±5.2 vs. 3.7±3.3 unit, P<0.001) and fresh frozen plasma (507.8±350.3 vs. 784.2±488.5 mL, P<0.001) transfused intraoperatively, preoperative D-dimmer level (11,361.0 vs. 2,856.7 mg/L, P<0.001) and reexploration for bleeding (15.8% vs. 2.4%, P<0.001). In multivariate analysis, risk factors for CRRT were CPB time (minute) [odds ratio (OR) 1.018; 95% confidence interval (CI), 1.007-1.029; P=0.002], preoperative sCr level (µmol/L) (OR, 1.008; 95% CI, 1.000-1.015; P=0.040), and the amount of red blood cell transfused intraoperatively (unit) (OR, 1.206; 95% CI, 1.077-1.350; P<0.001).

In this series of patients with TAAD, the time of CPB (minute), sCr level (µmol/L) and the amount of red blood cell transfused intraoperatively (unit) were risk factors for CRRT after TAR + FET.