Thorac Cardiovasc Surg 2016; 64 - OP175
DOI: 10.1055/s-0036-1571609

Combined Selective Cerebral and Lower Body Perfusion for Spinal Protection in a Frozen Elephant Trunk Simulation Model

P. Haldenwang 1, L. Häuser 1, N. Prochnow 2, D. Ziebura 2, A. Baumann 3, M. Sikole 1, M. Schlömicher 1, D. Buchwald 1, I. Schmitz 4, H. Christ 5, J. Strauch 1
  • 1Ruhr-University of Bochum / BGU Bergmannsheil, Department of Cardiothoracic Surgery, Bochum, Germany
  • 2Ruhr-University of Bochum, Department of Neuroanatomy and Molecular Brain Research, Bochum, Germany
  • 3Ruhr-University of Bochum / BGU Bergmannsheil, Department of Anesthesiology, Intensive Care, Palliative Care and Pain Medicine, Bochum, Germany
  • 4Ruhr-University of Bochum, Institute for Pathology, Bochum, Germany
  • 5University of Cologne, Institute for Medical Statistics, Informatics and Epidemiology, Cologne, Germany

Background: The ‘frozen elephant trunk’ procedure (FET) using isolated selective cerebral perfusion (SCP) at moderate hypothermia is associated with an increased risk for spinal cord ischemia. Aim of this study was to evaluate the neuroprotective effect of a combined selective and lower body perfusion (CLBP) in a porcine model.

Methods: 20 pigs (46 ± 5kg) were cooled on CPB to 28°C. After aortic clamping and occlusion of the thoracic segmental arteries (TSA T4-T13) a pressure controlled SCP (50 mm Hg) was established for 90min. Randomly, in n = 10 animals an additional lower body perfusion was performed with 15ml/kg/min (CLBP). Regional spinal blood flow (SCBF), liquor pressure (LP) and motor evoked potentials (MEP) were registered at six time points. The animals were sacrificed after 120 minute of weaning from CPB, and the spinal cord analyzed histologically using a schematic grading system (0 = normal, 8= total necrosis).

Results: Isolated SCP led to a SCBF-decrease from 18.5 ± 9.4 to 0.9 ± 1.4 ml/min/100 g in the L1-L5 region (p = 0.005). CLBP preserved an almost physiologic lumbar SCBF 11.3 ± 5.3 ml/min/100 g. LP decreased in both groups during cooling and SCP/CLBP to 70–80% and increased during reperfusion to 150%, showing higher values after isolated SCP. After CLBP a 95.8% MEP-recovery was observed, whereas isolated SCP resulted in MEP-recovery of only 61.8% in the L1-L5 area.

Fig. 1 Changes of MEP over time.

A higher grade of lumbar ischemia could be seen after isolated SCP (score: 5.9 ± 0.6 versus 3.6 ± 2.9).

Conclusion: 90min of SCP provide an insufficient lumbar spinal cord protection during FET-procedure at 28°C. Functional and structural spinal damage may be reduced using CLBP.