Retrograde cerebral perfusion (RCP) is a neuroprotective technique originally described in the early 1990s to deliver cold, oxygenated blood via the cardiopulmonary bypass (CPB) circuit to the cerebral vasculature by way of the superior vena cava (SVC) during deep hypothermic circulatory arrest (DHCA) for aortic surgery.
Most commonly, RCP is achieved with either a dedicated SVC cannula or as part of bicaval venous cannulation. Once the patient’s nasopharyngeal temperature is ~19°C, the patient is placed head down, and cold blood is directed to the cerebral venous system by snaring the SVC and flowing ~250-500 cc/min (20-40 mmHg). Blood enters the cerebral dural venous sinuses via the internal jugular veins.
Ultimately, this perfused blood is returned to the CPB circuit via cardiotomy suction placed in the open thoracic aorta. In a sense, RCP helps “flush out” embolic material from the cerebral vessels while also providing nutrients and maintaining cerebral hypothermia. With deep hypothermia, RCP provides similar neuroprotection compared to selective antegrade cerebral perfusion and is arguably a faster technique; however, valves located within the venous system may impede blood flow. Therefore, I’ll transduce pressure within the SVC cannula and use monitors like cerebral oximetry to gauge the efficacy of the RCP.