Heparin-coated bypass circuits in cardiopulmonary bypass: improved biocompatibility or not

Heparin bonding to bypass circuits has been found to reduce bleeding complications. Here, this process is reviewed with special attention to markers of inflammation and clinical outcome. Indicators of inflammation (i.e. cytokine levels, elastase and complement components) are decreased when using heparin bonded circuits compared to conventional bypass circuits. The decrease in the levels of these response modifiers appears minimal. Clinical outcomes, other than bleeding complications, have not been studied to any great extent with this technology. These lower levels of the various biological response modifiers are not correlated with lower levels of complications or shorter hospital stays. We conclude based on this data that it is not clear if this decrease translates into a clinical benefit in routine operative cases that require cardiopulmonary bypass.