57 The impact of preoperative renal dysfunction and therapy type in patients with type 2 diabetes undergoing coronary artery bypass surgery

Introduction There is limited data addressing the impact of preoperative renal dysfunction in type 2 diabetics (T2DM) undergoing first-time coronary artery bypass surgery (CABG); specifically exploring the influence of diabetic management (oral hypoglycaemic (OH) and insulin therapy (IN)). We assessed the impact of preoperative renal status and diabetic management on the post operative renal status, morbidity, 30-day and long-term survival in T2DM-CABG. Methods We reviewed prospectively accrued data from 1/1/1999 to 31/12/2009. Pre and 4 to 5-day postoperative creatinine clearance (CrCl) was calculated using Cockcroft-Gault formula. Patients were subgrouped into 5 grades based on preoperative CrCl; Group I CrCl≥90 ml/min; II 60–89; III 30–59; IV 15–29; V Results 1215 patients (921 males) with a mean age of 64 years (31–89 years) underwent CABG; 742 on OH and 472 on IN. Preoperative renal status in the groups were Group I -209(17%), II-584(48%), III-387(32%), IV-26(2%) and V (8(1%). Similar percentages in each group had ≥1 grade deterioration of renal function postoperatively 19%, 18%, 16% and 23% (grades I–IV respectively; p=0.470). When examined as a continuous variable, higher preoperative CrCl correlated with a better postoperative improvement in CrCl (r=0.073, p=0.012 Spearman Rank). Overall 30-day mortality was 3.33% (CI 2.32 to 4.34%) and was not different by group I-3.37% (CI 0.92 to 5.82), II-2.09% (CI 0.92 to 3.26%), III 4.92% (CI 2.76 to 7.08%), IV 8% (CI 0 to 18.6%) and Stage V 0% (CI 0 to 0.4%; p=0.101) or by therapy type; (p=0.411). IN patients had similar preoperative renal function (median CrCl 66.8 vs 68.6; p=0.828) but a higher rate of postoperative renal deterioration (53.3 vs 46.7%, p Conclusions In T2DM-CABG, 36% of patients have CrCl