T . Takeichi et al .: J Extra Corpor Technol 2025 , 57 , 32 – 37 35
Figure 2 . ( a – c ) The evaluation of the mixing zone if changing the flow rate from 3.0 L / min to 5.0 L / min by using 14Fr in the ascending aorta and 18Fr in the femoral artery . The black line indicates the mixing zone .
Figure
3 . ( a – c ) The evaluation of the mixing zone if changing the flow rate from 3.0 L / min to 5.0 L / min by using 14Fr in the ascending aorta and 16Fr in the femoral artery . The black line indicates the mixing zone .
combination of 14Fr in the Asc Ao and 16Fr in the FA , the mixing zone was placed at the descending aorta , and even at each flow rate , there were no major changes in the mixing zone . At 3.0 L / min , FA side flow : 1.3 L / min , Asc Ao side : 1.7 L / min . At 4.0 L / min , FA side flow : 1.7 L / min , Asc Ao side : 2.3 L / min . At 5.0 L / min , FA side flow : 2.1 L / min , Asc Ao side : 2.9 L / min ( Figures 3a – 3c ). When 14Fr in the Asc Ao and 20Fr in the FA were combined , the mixing zone was recognized at the aortic arch , and it remained the same place even when the flow rate was changed . At 3.0 L / min , FA side flow : 0.8 L / min , Asc Ao side : 2.2 L / min , At 4.0 L / min , FA side flow : 1.0 L / min , Asc Ao side : 3.0 L / min , At 5.0 L / min , FA side flow :
1.3 L / min , Asc Ao side : 3.7 L / min ( Figures 4a – 4c ). From these results , when changing the flow rate , the change was larger in 16Fr and 18Fr than in 14Fr . However , the smaller the size of the Asc Ao was than the size of the FA , the mixing zone tended to be closer to the aortic arch . Therefore , it was considered that our strategy for cannulation ’ s size choice for atherosclerotic and artheromic aorta is chosen until one size was up of FA cannulation size when performing perfusion Asc Ao and FA . Moreover , to prevent cerebral infarction in an atherosclerotic and artheromic aorta , the flow measuring of the Asc Ao and FA might be necessary . In the combination of 14Fr and 20Fr , the mixing zone substantially approached the aortic arch .