A simple technique for retrograde cerebral perfusion during circulatory arrest

Central cannulation is safe in acute aortic dissection repair

OBJECTIVE

The site of cannulation for the repair of ascending aortic dissection remains controversial. It is not clear whether cannulation of the dissected vessel is safe or even preferred. We hypothesized that cannulation of the dissected aorta could be done safely with acceptable complication and mortality rates in this high-risk population.

METHODS

The charts of repairs of acute ascending aortic dissections (n = 70) from 1996 to 2005 were reviewed. Cannulation was accomplished in 24 patients via the dissected aorta (central) and in 46 patients through cannulation of the femoral or axillary artery (peripheral). All were converted to sidearm cannulation of the graft for reperfusion. Groups were compared on the basis of comorbidities in addition to mortality, complications, hospital stays and final disposition.

RESULTS

The groups were comparable on the basis of age and preoperative comorbidities. Similarly, there were no differences in bypass time, crossclamp time, or hypothermic circulatory arrest time between groups. Hospital mortality and postoperative complications, including stroke, were similar between groups, but the peripheral group experienced more cardiac events (peripheral 15% vs central 0%; P < .05) and higher mortality than the central group (peripheral 19.5% vs central 4.2%; P < .05).

CONCLUSIONS

Direct cannulation of the dissected aorta was safe compared with peripheral cannulation in these patients. Inasmuch as these data demonstrate that cannulation of the dissected ascending aorta is safe, this technique can be used to tailor the cannulation approach to specific anatomic and patient characteristics that might optimize postoperative outcomes in this disease entity.

Neurological Complications of Aortic Surgery

Surgery of the aortic arch involves an inherently high risk of neurological complications. A number of factors have been identified which may predispose the patient to brain injury, and various techniques employed in an attempt to counteract these are outlined. In particular the vulnerability of the brain to ischemia has led to the development of three adjunctive cerebral protective techniques, hypothermic circulatory arrest, retrograde cerebral perfusion and selective antegrade cerebral perfusion, all based upon brain cooling and metabolic inhibition. The relative merits and disadvantages of these techniques are therefore discussed. Finally, pharmacologic adjuncts and potential future developments in aortic arch surgery are discussed.