Regarding “A randomized controlled trial and cost-effectiveness analysis of early cannulation arteriovenous grafts versus tunneled central venous catheters in patients requiring urgent vascular access for hemodialysis”

Abstract

We read with interest the results of the randomized trial conducted by Aitken and colleagues comparing the use of early cannulation arteriovenous grafts (ecAVGs) with tunneled central venous catheters (TCVCs) in patients requiring urgent vascular access.1Aitken E. Thomson P. Bainbridge L. Kasthuri R. Mohr B. Kingsmore D. A randomized controlled trial and cost-effectiveness analysis of early cannulation arteriovenous grafts versus tunneled central venous catheters in patients requiring urgent vascular access for hemodialysis.J Vasc Surg. 2017; 65: 766-774Abstract Full Text Full Text PDF PubMed Scopus (40) Google Scholar The provision of a 24-hour emergency ecAVG service is certainly commendable, and the paper clearly demonstrates that patients in the TCVC group experienced a considerably higher rate of culture-positive bacteremia than those in whom an ecAVG had been placed. We are, however, concerned at one of the unintended consequences of the study. It is notable that at 6 months, relatively few patients (∼20%) were undergoing dialysis through an arteriovenous fistula (AVF). This is particularly the case for the TCVC group, in which only 16% of patients were using a functional AVF at the end of the study. Furthermore, despite managing to perform ecAVG placement promptly (median wait of 14 hours), simultaneous AVFs were created in only approximately half of the patients in this group. The authors state that they “do not advocate choosing an AVG over a native fistula” and that rather than a study of ecAVGs vs TCVCs, they “consider this to be a study comparing strategies and approaches to vascular access provision,” such that their findings “support a culture of ‘Fistula First.’” Thus, whereas the authors are to be congratulated on developing a service for rapid ecAVG insertion, we must question if the focus on early graft placement compromised the opportunity for AVF creation. This is particularly the case for the TCVC group, who surprisingly waited longer for their line insertion than those in the ecAVG group waited for graft placement and in whom only a third underwent AVF creation as part of their initial vascular access strategy. Was access to the operating room a limiting factor in providing fistula surgery in this group, and if so, was this compounded by the use of the operating room for either inserting ecAVGs or dealing with their associated thrombotic and stenotic complications? One wonders whether the outcomes of the trial would have been different if the TCVC group had received the same focus as the ecAVG group, with prompt insertion of a permanent line without the need for a bridging catheter, but more important, with a commitment to create an AVF at the earliest opportunity. A randomized controlled trial and cost-effectiveness analysis of early cannulation arteriovenous grafts versus tunneled central venous catheters in patients requiring urgent vascular access for hemodialysisJournal of Vascular SurgeryVol. 65Issue 3PreviewEarly cannulation arteriovenous grafts (ecAVGs) are proposed as an alternative to tunneled central venous catheters (TCVCs) in patients requiring immediate vascular access for hemodialysis (HD). We compared bacteremia rates in patients treated with ecAVG and TCVC. Full-Text PDF Open ArchiveReplyJournal of Vascular SurgeryVol. 66Issue 3PreviewWe are grateful for the opportunity to respond to Mr Pettigrew's letter. He identifies two salient points: first, that the time to obtaining a tunneled catheter was greater than that of getting an arteriovenous graft. We are not aware of any center, before this study or subsequently, that routinely measures the time required to obtain access of any type. We believe this most often relates to a lack of overarching stewardship across the entirety of vascular access provision, with surgery, imaging, and nephrology all having differing priorities when considering access services. Full-Text PDF Open Archive