The effect of postocclusion reactive hyperaemia, papaverine and nifedipine on duplex derived haemodynamic parameters of infrainguinal bypass grafts

Abstract

Duplex derived flow measurement of infrainguinal bypass grafts can evaluate graft and limb haemodynamics in the postoperative period. Pharmacological manipulations, such as vasodilation, can influence the physiological runoff with subsequent increase in volume flow through the graft.

Mesenteric stenosis, collaterals, and compensatory blood flow

“…It is known that vasodilating stimuli (eg, papaverine) are able to increase flow in bypass grafts. 33 In the study of Karacagil et al, 34 increase in PSV, mean velocity, and flow volume was found in autografts. 33 This effect has also been demonstrated in allograft bypasses, pointing to a decreased peripheral resistance causing an increased flow without change of diameter.…”

“…33 In the study of Karacagil et al, 34 increase in PSV, mean velocity, and flow volume was found in autografts. 33 This effect has also been demonstrated in allograft bypasses, pointing to a decreased peripheral resistance causing an increased flow without change of diameter. In the study of Boley et al, 35 collateral flow was studied in dogs during experimental reduction of SMA flow.…”

Interpretation of the Results of Doppler Ultrasound Flow Volume Measurements of Infrainguinal Vein Bypasses

“…Previous papers describe changes in the flow volume in the reconstruction zone, both before and after application of vasodilatative substances. [12][13][14] With in situ bypasses, unligated side branches can be detected. 15 Stirnemann et al found that, in order for a reconstruction to remain open, vein bypasses require 10 ml/min minimum flow and PTFE bypasses require 50 ml/min.…”

“…1 The diameter of the bypass vein and the peripheral resistance also have an influence on the flow. 13,21 Ascer et al showed, that the outflow resistance predicts late patency of infrainguinal bypasses and limb salvage. 22,23 Intraoperatively, the application of vasodilatative substances into the bypass reduces the peripheral resistance and increases the flow.…”