Moderate Hypothermia (30 °C) for Surgery of Acute Type A Aortic Dissection

Abstract

Objective: Antegrade cerebral perfusion has proved to be a reliable method of brain protection during surgery of thoracic aneurysms. In addition, the drawbacks of deep hypothermia may be avoided. This study examines the outcome after surgery for acute type A aortic dissections (AAD) using moderate (30 °C) systemic hypothermia compared with conventional techniques of cerebral protection. Methods: Between January 1999 and August 2003, 74 patients underwent repair of acute type A aortic dissection. Moderate systemic hypothermia (30 °C) with selective antegrade cerebral perfusion through subclavian artery (group A) was used in 18 patients. Deep hypothermia (20 - 24 °C) was employed using either retrograde (18 patients, group B) or antegrade (38 patients, group C) cerebral perfusion. Tube graft replacement was performed in 55, valve-sparing procedure in 8, and composite graft replacement in 11 patients. Results: The 30-day mortality was 5.5 % in group A, 5.5 % in group B, and 15.8 % in group C (A vs. C and B vs. C; p < 0.01). New postoperative permanent neurologic deficit occurred in 5.5 % of patients in group A, 16.7 % in group B, and 13.2 % in group C. Mean chest tube drainage within the first 24 h in groups A, B and C was 703 ± 338, 1178 ± 820, and 1447 ± 802 ml, respectively (A vs. B and A vs. C; p < 0.01). Cardiopulmonary bypass, ICU, and hospital times were significantly shorter in group A. Conclusions: Selective antegrade cerebral perfusion with moderate systemic hypothermia appears to be a safe and sufficient tool for brain protection during AAD repair. In avoiding deep hypothermia, this technique may help to reduce cardiopulmonary bypass time and hypothermia-related side effects.

Cerebral protection - aortic arch - moderate hypothermia - circulatory arrest - antegrade cerebral perfusion - aortic dissections

References

• 1 Griepp R B, Stinson E B, Hollingsworth J F, Buehler D. Prosthetic replacement of aortic arch.  J Thorac Cardiovasc Surg. 1975;  70 1051-1053
• 2 Ueda Y, Miki S, Kusuhara K. et al . Surgical treatment of aneurysms or dissections involving the ascending aorta and aortic arch, utilizing circulatory arrest and retrograde cerebral perfusion.  J Cardiovasc Surg. 1990;  31 553-558
• 3 Kazui T, Kimura N, Yamada O, Komatsu S. Surgical outcome of aortic arch aneurysms using selective antegrade perfusion.  Ann Thorac Surg. 1994;  57 904-911
• 4 Ergin M A, Galla J D, Lansman S L, Quintana C, Bodian C, Griepp R B. Hypothermic circulatory arrest on operations on the thoracic aorta: determinants of operative mortality and neurologic outcome.  J Thorac Cardiovasc Surg. 1994;  107 788-797
• 5 Mezrow C K, Sadeghi A M, Gandsas A, Shiang H H, Levy D, Green R. et al . Cerebral blood flow and metabolism in hypothermic circulatory arrest.  Ann Thorac Surg. 1992;  54 609-616
• 6 Ehrlich M P, Hagl C, McCullough J N. et al . Retrograde cerebral perfusion provides negligible flow through brain capillaries in the pig.  J Thorac Cardiovasc Surg. 2001;  122 331-338
• 7 Ye J, Yang L, Del Bigio M R. et al . Retrograde cerebral perfusion provides limited distribution of blood to the brain: a study in pigs.  J Thorac Cardiovasc Surg. 1997;  114 660-665
• 8 Reich D L, Uysal S, Ergin A, Griepp R B. Retrograde cerebral perfusion as a method of neuroprotection during thoracic aortic surgery.  Ann Thorac Surg. 2001;  72 1774-1782
• 9 Hagl C, Ergin M A, Galla J D. et al . Neurologic outcome after ascending aorta-aortic arch operations: effect of brain protection technique in high-risk patients.  J Thorac Cardiovasc Surg. 2001;  121 1107-1121
• 10 Crittenden M D, Roberts C S, Rosa L. et al . Brain protection during circulatory arrest.  Ann Thorac Surg. 1991;  51 942-947
• 11 Bachet J, Guilmet D, Goudot B. et al . Cold cerebroplegia: a new technique for cerebral protection during operations on the transverse aortic arch.  J Thorac Cardiovasc Surg. 1991;  102 85-94
• 12 Kazui T, Washiyama N, Mohammad B AH, Terada H, Yamashita K, Takinami M. Improved results of atherosclerotic aneurysm surgery using a refined technique.  J Thorac Cardiovasc Surg. 2000;  121 491-499
• 13 Strauch J T, Spielvogel D, Haldenwang P L. et al . Impact of hypothermic selective cerebral perfusion compared with hypothermic cardiopulmonary bypass on cerebral hemodynamics and metabolism.  Eur J Cardiothorac Surg. 2003;  24 807-816
• 14 Takahara Y, Mogi K, Sakurai M, Nishida H. Total aortic arch grafting via median sternotomy using integrated antegrade cerebral perfusion.  Ann Thorac Surg. 2003;  76 1485-1489
• 15 Ehrlich M P, McCullough J N, Zhang N. et al . Effect of hypothermia on cerebral blood flow and metabolism in the pig.  Ann Thorac Surg. 2002;  73 191-197
• 16 Usui A, Oohara K, Murakami F, Ooshima H, Kawamura M, Murase M. Body temperature influences regional tissue blood flow during retrograde cerebral perfusion.  J Thorac Cardiovasc Surg. 1997;  114 440-447
• 17 Fann J I, Smith J A, Miller D C. et al . Surgical management of aortic dissection during a 30-year period.  Circulation. 1995;  92 (Suppl 9) II113-121
• 18 Takeuchi R, Matsuda H, Yonekura Y, Sakahara H, Konishi J. Noninvasive quantitative measurements of regional cerebral blood flow using technetium-99 m - L, L-ECD SPECT activated with acetazolamide: quantification analysis by equal-volume-split 99 mTc-ECD consecutive SPECT method.  J Cereb Blood Flow Metab. 1997;  17 1020-1032