OBJECTIVE: steal phenomenon following an @entity2548 ( @entity2548 ) creation is characterised by retrograde flow in the artery segment distal to the @entity254 and occurs in the majority of @entity1 with radiocephalic @entity2548 although this rarely leads to distal ischaemia. To investigate the local haemodynamics after the creation of an @entity2548 , a simple electrical resistance model which assumes time-independent flow was used. The applicability of this model to pulsatile flow conditions was verified using an in vitro flow circuit. The effects of stenoses in various artery segments were also investigated. DESIGN OF THE STUDY: the electrical analogue model consists of a pressure source, constant resistances that represent the resistance to flow of various @entity17954 . The @entity850 was modelled by a resistor and a non-linear term is simulated by a current-controlled voltage source. In vitro experiments were performed in pulsatile and steady flow and the results were compared with electrical simulations. The effects of fistula flow and the presence and severity of a @entity850 on flow distribution, particularly the direction of flow in the distal radial artery and flow into the hand were assessed. RESULTS: steady and pulsatile time-averaged flows measured in vitro compared well with the results of electrical circuit simulations for cases without a @entity850 . When a @entity850 was present comparisons were made only in steady flow and these show good agreement for stenoses of 75% area reduction. The direction of flow in the distal radial artery was antegrade (towards the hand) at low fistula flow and became retrograde as fistula flow increased. The presence of a severe @entity850 in the brachial artery was found to have the strongest influence on flow to the hand. CONCLUSIONS: an electrical resistance model of a radiocephalic @entity2548 has been validated with an in vitro pulsatile flow circuit. One of the benefits of this model is that it can be easily analysed using standard circuit simulation software. The model also provide insights into the possible haemodynamics consequences of creating an @entity2548 with or without the presence of a @entity850 in the arterial segments.

Steal phenomenon in radiocephalic XXXX . In vitro haemodynamic and electrical resistance simulation studies.

@entity1 :: ('9606', 'Species') :: ['patients'] @entity850 :: ('MESH:D003251', 'Disease') :: ['stenosis'] @entity254 :: ('MESH:C563598', 'Disease') :: ['anastomosis'] @entity17954 :: ('MESH:D016157', 'Disease') :: ['arterial segments and the fistula'] @entity2548 :: ('MESH:D001164', 'Disease') :: ['AVF', 'arteriovenous fistula']
@entity2548 :: (MESH:D001164,Disease) :: ['arteriovenous fistula']
