Catheters in Dialysis Linked to High Risk of Infection

A new study shows that dialysis patients using catheters for blood access have the highest risks for death, infections, and cardiovascular (CV) events.

Researchers at the University of Calgary (Canada), the University of Otago (Christchurch, New Zealand), and other institutions conducted a systematic review of cohort studies to evaluate the associations between type of vascular access (arteriovenous fistula, arteriovenous graft, and central venous catheter) and risk for death, infection, and major CV events. The researchers searched MEDLINE, EMBASE, and other article reference lists and extracted data describing study design, participants, vascular access type, clinical outcomes, and risk for bias. In all, 62 cohort studies comprising 586,337 participants met the inclusion criteria.

The results showed that when compared with patients with an arteriovenous fistula, those using catheters had a 38% higher risk of experiencing a major heart-related event, a 53% higher risk of dying, and more than twice the risk of developing fatal infections. Patients with arteriovenous grafts had an 18% increased risk of dying and a 36% increased risk of developing fatal infections compared to those with an arteriovenous fistula, but they did not have an increased risk of experiencing a major heart-related event. The study was published early online on February 21, 2013, in the Journal of the American Society of Nephrology (JASN).

“Our findings are reflected in current clinical practice guidelines, which promote fistulas as the preferred form of bloodstream access in hemodialysis patients,” said lead author Pietro Ravani, MD, of the University of Calgary, and colleagues. “Better quality data are needed, but not from studies with the same design as those already available. In fact, our cumulative meta-analysis shows that this information was already available 10 years ago.”

An arteriovenous fistula is currently the most recommended access for kidney disease patients who must undergo dialysis, created by connecting a patient's vein and artery to form a long-lasting site through which blood can be removed and returned. Alternatively, in patients who are unsuitable for a fistula, an arteriovenous graft—a plastic conduit between an artery and a vein—may be used. Many patients, however, prefer a catheter, for reasons that include inadequate preparation for dialysis, avoidance of surgery, or fear of needles (since the connection to the dialysis machine via a catheter does not require needles).

Related Links:
University of Calgary
University of Otago