Objectives: The aim of the present study was to analyse the effects of various vasodilating stimuli on postoperative infrainguinal graft haemodynamics.
Design: Duplex derived haemodynamic parameters of infrainguinal bypass grafts were measured at rest and after postocclusion reactive hyperaemia, intraarterial papaverine (40 mgm) injection and peroral nifedipine (10 mg) administration.
Setting: Department of Surgery, University Hospital.
Materials: Twenty-nine patients with infrainguinal bypass grafts were studied by Duplex scanner after a median of 25 months postoperatively.
Chief outcome measures: Peak systolic velocity (PSV), mean velocity (MV) and volume flow (VF) were measured at rest and after various stimuli.
Main results: VF at rest increased from 125 +/- 16 ml/min (mean +/- S.E.M.) to 271 +/- 26 ml/min after papaverine administration and to 205 +/- 19 ml/min during reactive hyperaemia (p < 0.001). PSV, MV and VF increased significantly during postocclusion reactive hyperaemia and papaverine injection. After nifedipine administration VF increased to 154 +/- 21 ml/min after 30 min (p < 0.001) and there was a significant increase in MV (p < 0.05).
Conclusions: 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.