Response to Letters Regarding Article “Aprotinin Does Not Increase the Risk of Renal Failure in Cardiac Surgery Patients”

Abstract

We would like to thank Drs Karkouti, Beattie, Bouchard, Mathew, Metha, Agoustides, Landis, Taylor, and Poston for their interest in our study1 and their comments. We agree wholeheartedly with Drs Landis, Taylor, and Poston. We also agree with Dr Agoustides that the inclusion of angiotensin-converting enzyme inhibitor therapy and detailed dose information for aprotinin would lend further discrimination to our model. Unfortunately, although we wished to include such potential confounders in our analysis, these variables were not available in our dataset. We applaud Drs Bouchard, Mathew, and Metha for pointing out the universal flaw of this sort of research: that is, the lack of a uniform definition of clinically significant renal dysfunction. Retrospective analyses do not allow for the inclusion of >6 hours of oliguria, although prospective trials might. Because Mangano et al2 and Karkouti et al3 used differing definitions of renal dysfunction based on either …