Use of Phenoxybenzamine [PBZ] IV to Assist High Flow Low Pressure Perfusion [HFLPP] on Cardio-pulmonary Bypass

Cardiopulmonary bypass \[CPB\] in small size bodies can result in decreased peripheral perfusion. This results in anaerobic metabolism as evidenced by lactic acidosis. High flow perfusion results in systemic hypertension which is accentuated by moderate hypothermia commonly used during cardiopulmonary bypass. Phenoxybenzamine \[PBZ\] is an arteriolar vasodilator that acts by irreversibly blocking the alpha adrenergic receptors. It causes vasodilatation allowing high flow, low pressure CPB. It has been used extensively outside US in Canada, Europe and Australia. In the US oral PBZ is FDA approved, whereas intravenous PBZ is only available as an investigational drug