CABG Guidebook 2

12. TTFM EXAMPLES - NORMAL FLOW PATTERNS ON-PUMP & CLAMP ON To verify that the distal anastomosis is open and that there is no occlusion of the graft, check the flow while the clamp is on. Expect higher mean flow and lower PI than when measuring off-pump. According to Kieser et al., PI should be below 0.3-0.4 at this point. High flows on-pump might indicate competitive flow if the stenosis is <70%. 6 For on-pump measurements, DF% is not relevant.