Graftula: a composite access consisting of a graft used to repair a dysfunctional hemodialysis fistula.

Nonmaturing or dysfunctional hemodialysis fistulas are often repaired with interposition grafts placed either within the fistula (fistula-to-fistula configuration), or connected to another vein (fistula-to-vein configuration). The goal of this study was to compare the survival and usefulness of the composite accesses thus created, which we call "graftulas," with upperarm grafts. This was a retrospective study wherein we determined the survival and thrombosis rates of graftulas (n=24) and upper arm grafts (n=31) placed 1/1/07 through 12/31/09 and followed through 11/30/10.

Thigh grafts contribute significantly to patients' time on dialysis.

Background And Objectives: Thigh grafts are placed in hemodialysis patients who have exhausted all arm access sites. The goal of this study was to compare the survival, complication rates, and overall contribution of thigh grafts with arm grafts and fistulas in patients with at least one functional thigh graft during their dialysis history.

Design, Setting, Participants, & Measurements: This longitudinal review of a prospectively acquired clinical database included 85 thigh graft recipients.

Thigh grafts: a preferable alternative to catheters when upper extremity access sites are exhausted.

Hemodialysis patients with failed upper extremity (arm) access sites comprise 5-10% of the dialysis population. In these patients, arm vessels are either unsuitable for access placement due to trauma or peripheral vascular disease, or have been exhausted following dialysis usage. Synthetic grafts in the lower extremity (thigh) would benefit these patients, but surgeons are often reluctant to place them, due to concerns of infection and vascular complications.

Risk of hemodialysis graft thrombosis: analysis of monthly flow surveillance.

Background: During clinical application of flow surveillance of hemodialysis grafts, the risk of thrombosis is assessed month after month, rather than after one or several measurements, as has been done in published studies. Adequate assessment of risk should consider the many measurements obtained over time.

Study Design: Prospective cohort diagnostic test study.

Inflow stenosis obscures recognition of outflow stenosis by dialysis venous pressure: analysis by a mathematical model.

Background: Recent studies have shown that inflow stenosis of haemodialysis grafts is more common than previously realized. The influence of inflow stenosis on graft haemodynamics and venous pressure (VP) surveillance has not been previously systematically studied.

Methods: We used a well-established mathematical model to determine the relation between inflow stenosis and static VP (adjusted for mean arterial pressure, VP/MAP), outflow stenosis and artery and vein luminal diameters.

Mathematical model demonstrates influence of luminal diameters on venous pressure surveillance.

Background: The reliability of dialysis venous pressure (VP) in detecting stenosis is controversial. A mathematical model may help to resolve the controversy by providing insight into the factors that influence static VP.

Design, Setting, Participants, And Measurements: This study used inflow artery and outflow vein luminal diameters from duplex ultrasound studies of 94 patients.

Stenosis surveillance of hemodialysis grafts by duplex ultrasound reduces hospitalizations and cost of care.

Most recent randomized controlled trials (RCTs) have found that hemodialysis graft surveillance combined with preemptive correction of stenosis does not prolong graft survival. Nevertheless, such programs may be justified if they reduce other adverse outcomes or decrease the cost of care. This study tested this hypothesis by applying a secondary analysis to our original RCT.

In vivo validation of glucose pump test for measurement of hemodialysis access flow.

Background: The glucose pump test (GPT) is a recently introduced method of measuring hemodialysis access blood flow (Qa). A validation of GPT during dialysis has not yet been done, and performance characteristics of the method have not yet been fully analyzed.

Methods: The authors studied 33 patients (25 synthetic grafts, 8 autogenous arteriovenous fistulae).

A randomized controlled trial of blood flow and stenosis surveillance of hemodialysis grafts.

Background: It is widely accepted that hemodialysis graft surveillance combined with correction of stenosis reduces thrombosis and prolongs graft survival. Nevertheless, few randomized controlled trials have evaluated this approach.

Methods: In this randomized controlled trial, 101 patients were assigned to control, flow (Qa), or stenosis groups, and were followed for up to 28 months.

Association between blood pressure, ultrafiltration, and hemodialysis graft thrombosis: a multivariable logistic regression analysis.

Although a low blood flow (Q(a)) is the most important cause of graft thrombosis, several studies have shown that Q(a) measurements do not accurately predict thrombosis. This suggests that additional variables may influence thrombosis. Identification of such variables may be essential to designing surveillance protocols that accurately predict thrombosis.

Vascular access: anatomy, examination, management.

A systematic approach to managing vascular access problems is the key to reducing current high rates of access thrombosis and failure. This approach begins with a thorough knowledge of vascular access anatomy that, when combined with the physical examination, can help optimize access planning and maintenance. Because of the high complication rate of synthetic grafts, there has been increased emphasis on creating autogenous arteriovenous (AV) fistulae, which, once established, are more trouble-free.