This has been discussed between the renal division and the cardiac surgery division in my institution. We know that AKI post cardiac surgery is an independent prognostic factor for mortality (Am J Nephrology 2010 31 408). It’s a big deal! But what can we do about it?
The etiology for AKI post cardiac surgery is multi-factorial but one of them is the length of time on cardiopulmonary bypass. Postulated mechanisms are the inflammatory response, ischemia, micro-embolization of gaseous particles, etc. (Perfusion 2006 21 209). One may then wonder if off-pump CABG would prevent post-op AKI and reduce mortality.
The answer comes from a recent study (NEJM 2012 366 1489) showing that the off-pump CABG group had fewer episodes of AKI (defined as a creatine rise of more than 0.3 mg/dl), 28% v. 32% (p = 0.01). However, the 30-day mortality was not different between off-pump and on-pump CABG... It is speculated that this may be due to intra-operative hypotension, technical issues, etc.