Cerebral physiology of cardiac surgical patients treated with the perfluorocarbon emulsion, AF0144

Background. Perfluorooctyl bromide is a biologically inert compound with short biologic retention and high oxygen solubility. The purpose of this study was to assess the effect of the perfluorocarbon emulsion, AF0144 (Perflubron, Alliance Pharmaceutical Corp, San Diego, CA), used in conjunction with acute normovolemic hemodilution on cerebral blood flow and cerebral emboli measurements during coronary artery bypass grafting with cardiopulmonary bypass. Methods. Thirty-six adult cardiac surgical patients were enrolled in a single-institution, randomized, controlled, single-blind dose escalation trial. Autologous whole blood was harvested from each patient to target an on-bypass hematocrit of 20% to 22%. Placebo, low dose (1.8 g/kg) or high dose (2.7 g/kg) AF0144 was administered. Transcranial Doppler ultrasonography was used to quantitate cerebral emboli and xenon-133 clearance was used to measure cerebral blood flow. Results. Cerebral blood flow was increased in both AF0144-treated groups compared with placebo (p = 0.006, low dose vs control; p = 0.036, high dose vs control). Numbers of cerebral emboli were greater in the high-dose AF0144-treated group versus control during the time periods from aortic cannulation through aortic cross-clamp placement (p = 0.026) and from aortic cross-clamp placement through cross-clamp removal (p = 0.008). Conclusions. The perfluorocarbon emulsion, AF0144, increased cerebral blood flow during cardiopulmonary bypass. In addition, total cerebral emboli load during bypass was greater in patients receiving high-dose AF0144.