Are preventive interventions needed for dialysis patients?
An arteriovenous access consists of a direct surgical connection between an artery and a vein in the arm (fistula) or a plastic conduit connecting an artery and a vein (graft). If these forms of access become dysfunctional, the delivery of dialysis therapy becomes suboptimal. The most common cause of access dysfunction is the development of a restriction or conduit narrowing called 'stenosis'. Because early correction of stenosis is considered critical to maintain the openness of the access and prolong its use, guidelines recommend regular screening based on diagnostic tests in addition to or instead of a physical exam to identify and treat early lesions.
A team of Cochrane authors based in Canada, Australia, New Zealand, and Italy worked with Cochrane Kidney and Transplant to evaluate whether pre-emptive correction of an AV access stenosis improves clinically relevant outcomes and how the effects differ. 14 studies were included, with a total of 1,390 participants.
This Cochrane Review found that pre-emptive correction of a newly identified or known stenosis in a functional haemodialysis access does not increase access longevity, particularly in grafts. Although pre-emptive stenosis correction may be promising in fistulas, existing evidence is insufficient to guide clinical practice and health policy. While pre-emptive stenosis correction may reduce the risk of hospitalisation, there may be a substantial increase (80%) in the use of access-related procedures and procedure-related adverse events, such as infection or mortality. The net effects of pre-emptive correction on harms and resource use are thus unclear.
“The evidence found does not support pre-emptive correction of stenosis in a functional arteriovenous access,” said Pietro Ravani, the lead author of the Cochrane Review and researcher at the University of Calgary in Canada. “There has been a lot of interest in pre-emptive correction of a stenosis in a functioning access to prevent clotting and extend the duration of access use. However, the evidence indicates that more harm than good may be done with this practice.”