Safe Cerebral Protection: Introduction to Isolated Cerebral Perfusion and Repair of Type A Dissection With Body Normothermia

This introductory video describes the Gaudiani technique of cerebral perfusion at hypothermia, while the body is kept normothermic, for major aortic cases. The key issue that this technique addresses is that the body does not need to be hypothermic in cases of circulatory arrest, but it is mostly made hypothermic so that the blood that goes to the head is kept hypothermic, at around 20 °C. Cerebral protection must be at low temperatures due to the fact that only one heater/cooler is used, thus only one temperature can be chosen. 

Vince Gaudiani’s technique disrupts this concept by splitting the aortic cannulae into two circuits after the oxygenator so that the aortic cannula that perfuses the brain can deliver cooled blood at 20 °C, while the cannula that delivers blood to the body can be kept warm at around 34 °C. This has the very considerable advantage of reducing rewarming times and reducing hypothermic injury to the bodies organs. It also has the advantage of eliminating the risk of emboli to the brain, as the cerebral circuit provides continuous blood to the brain and is isolated from the body so that no air emboli or debris can pass into the head vessels. 



This video documents Dr. Gaudiani’s novel technique for repair of a type A aortic dissection. In this method, the head and body were perfused with separate circuits, allowing the head to be cooled to 20 °C while the body stayed warm at 34 °C. 

First, a non-dissected vessel to the head was cannulated and the head cooled while the body was kept warm at approximately 32 °C. A femoral arterial cannula was also placed. A small pediatric cannula was used in the innominate artery and flow of one liter per minute was given to the head.

Next, a retrograde cardioplegia cannula was placed and a right superior vein vent was used. The head was perfused at one liter from the start of the operation, which prevented any emboli to the head and allowed for a shorter time to rewarm, as the body did not need to be rewarmed. 

The aorta was then resected and the aortic valve was preserved. An interposition graft was then placed. Horizontal mattress sutures were used on the proximal aorta to put the adventitial and intimal layers together, and BioGlue was used to reinforce the dissected aortic wall. 

Next, the distal aortic clamp was removed and the distal aorta was reinforced with a patch of pericardium between the adventitial layer and the intimal layer, which was loosely sutured in place with a continuous suture. These layers were also glued with BioGlue. 

A Dacron tube graft was then sutured in place but sutured inside the aorta rather than end to end. For this case, the proximal anastomosis was also done with the cross clamp off, as there was so little time required for rewarming. After the proximal anastomosis was done, it took only 20 minutes to fully rewarm the patient. There was blood flowing down the carotid vessels during deairing to further prevent air emboli to the brain. Dr. Gaudiani’s mortality rate is aproximately 7 percent for these difficult cases. 

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