Experimental selective antegrade cerebral perfusion (SACP)

Aortic arch surgery requires circulatory arrest and cerebral protection relies on deep hypothermia, selective perfusion of the brain by antegrade (SACP) or retrograde routes or combinations thereof. Perioperative morbidity and mortality is substantial. 

Based on the clinical uncertainty regarding the lower ischemic threshold during SACP, we have focused our scientific efforts on defining the metabolic response to low flow SACP. This is of particular clinical relevance, since high flows may be associated with unwanted side effects such as hypertension, edema and increased risk for embolism. 

In order to study the cerebral response to SACP, we use magnetic resonance imaging and spectroscopy as well as near-infrared light spectroscopy (NIRS) and microdialysis. 

The group has previously published experimental findings supporting the use of SACP at 20 degrees centigrade vs. hypothermic cardiac arrest and SACP at moderate hypothermia [1]. 

Recently, we were able to substantiate the flow level of 6 ml/kg/min as a potential ischemic threshold at 20 degrees centigrade in the same model, and we also described previously unknown regional variations in perfusion that could be of pathogenic importance to the occurrence of intraoperative cerebral ischemia [2]. 

Currently, we analyze further the lower flow limits of SACP using PET technique and we aim to continuing the scientific efforts to outline the patophysiology of neurological damage following SACP during the next years. 

Publications 

  1. Jonsson O, Myrdal G, Zemgulis V, Valtysson J, Hillered L, Thelin S: Selective antegrade cerebral perfusion at two different temperatures compared to hypothermic circulatory arrest--an experimental study in the pig with microdialysis. Interact Cardiovasc Thorac Surg 2009, 8(6):647-653.
  2. Jonsson O, Morell A, Zemgulis V, Lundstrom E, Tovedal T, Einarsson GM, Thelin S, Ahlstrom H, Bjornerud A, Lennmyr F: Minimal Safe Arterial Blood Flow During Selective Antegrade Cerebral Perfusion at 20 degrees Centigrade. Ann Thorac Surg. 2011 Apr;91(4):1198-205.
  3. Tovedal T, Jonsson O, Zemgulis V, Myrdal G, Thelin S, Lennmyr F.: Venous obstruction and cerebral perfusion during experimental cardiopulmonary bypass. Interact Cardiovasc Thorac Surg 2010;11(5):561-566
  4. Tovedal T, Myrdal G, Jonsson O, Bergquist M, Zemgulis V, Thelin S, Lennmyr F. Experimental treatment of superior venous congestion during cardiopulmonary bypass. Eur J Cardiothorac Surg. 2013 Sep;44(3):e239-44

Group members

Thomas Tovedal, Mark Lubberink*, Arvid Morell*, Ove Jonsson, Gunnar Myrdal, Vitas Zemgulis, Sergio Estrada*, Gunnar Antoni*, Stefan Thelin, Fredrik Lennmyr

Collaboration with Departments of Hospital Physics and PET-center.