In current practice, the vacuum-assisted closure system is often used in the treatment of mediastini- tis.913 With it, local negative pressure is applied to the open wound, accelerating granulation tissue formation and increas- ing blood supply. Such vacuum-assisted closure therapy, which is less invasive than conventional surgical treatment, has been used as standalone therapy, as a bridge to flap advancement, or as sternal preconditioning and preservation followed by titanium plate sternal osteosynthesis.913,914,973 Although several studies have suggested that vacuum- assisted closure therapy can be a successful alternative to conventional standard therapy,913 921,973 the data are from single-center retrospective studies of patients with heteroge- neous disease processes. As a result, it seems reasonable to suggest that both conventional and vacuum-assisted closure therapy can be used in the treatment of mediastinitis. 5.2.3. Renal Dysfunction: Recommendations Class IIb 1. In patients with preoperative renal dysfunction (cre- atinine clearance <60 mL/min), off-pump CABG may be reasonable to reduce the risk of acute kidney injury (AKI).974 978 (Level of Evidence: B) 2. In patients with preexisting renal dysfunction under- going on-pump CABG, maintenance of a perioper- ative hematocrit greater than 19% and mean arte- rial pressure greater than 60 mm Hg may be reasonable. (Level of Evidence: C) 3. In patients with preexisting renal dysfunction, a delay of surgery after coronary angiography may be reasonable until the effect of radiographic contrast material on renal function is assessed.979 981 (Level of Evidence: B) 4. The effectiveness of pharmacological agents to pro- vide renal protection during cardiac surgery is un- certain.982 1004 (Level of Evidence: B) See Online Data Supplements 37 to 39 for additional data on CABG and renal dysfunction. 