Table 3.

Vascular access outcomes (according to the recommendations of the Committee on Reporting Standards for Arteriovenous Accesses, Society for Vascular Surgery and American Association for Vascular Surgery).

AV access outcome	Definition
Access primary failure	Permanent failure of the fistula or graft before hemodialysis suitability. This includes inadequate maturation, thrombosis, failure of first and subsequent cannulations, and other complications leading to nonfunctional fistula or graft.
Successful cannulation	The AV access became the primary vascular access for hemodialysis (the fistula or graft access has been cannulated with two 16- or 15-gauge needles for ≥3 consecutive dialysis sessions and the TCVC was removed).
Suitability for hemodialysis	Fistula or graft use with two needles and maintenance of blood flow ≥300 ml/min for ≥75% of dialysis sessions over a continuous 4-week. The maturation criteria can be satisfied at any time within 6 months of fistula or graft creation surgery.
Unassisted access maturation	Criteria for fistula or graft suitable for hemodialysis (based on the above criteria) are met before any endovascular or secondary surgical procedure to facilitate maturation.
Assisted access maturation	Satisfaction of the criteria for fistula or graft suitability for hemodialysis after a procedure to facilitate maturation (e.g., angioplasty, stent placement, surgical revision, ligation of accessory veins).
Access primary patency	Procedure-free access survival defined as the time from index fistula or graft creation to the first of one of the following events: access thrombosis; any procedure designed to facilitate, maintain, or re-establish patency.
Access assisted primary patency	Interval of time from index fistula or graft creation until the first of one of the following events: access thrombosis, censoring event, or study end. This period includes all procedures (surgical or endovascular) designed to maintain the functionality of the dialysis vascular access as long as access patency was not lost.
Access cumulative patency	Interval of time from index fistula or graft creation until access abandonment, censoring event, or study end. This period include access primary patency period and access assisted primary patency period.
Post-procedure primary patency	Interval of time from the first procedure designed to maintain the functionality of the index dialysis vascular access until the first of one of the following events: access thrombosis; any procedure designed to facilitate, maintain, or re-establish patency; censoring event; or study end.
Noninfectious complications	Stenosis, thrombosis, hand ischemia, aneurysm, pseudoaneurysm, infiltration.
Infectious complications	Fistula or graft cellulitis, abscess, bacteremia.
Access procedures	Angioplasty, stent placement, surgical revision, ligation of accessory veins, superficialization of vein.
Other clinical outcomes	TCVC placement, new AV access surgical creation, AV access–related hospitalization or death.
Limb ischemia following AV access placement
Symptoms	Paresthesia, pain, hand stiffness, ulceration and tissue loss in the limb with AV access.
Physical examination	Diminished or absent radial pulse, pallor, diminished sensation, and, in advanced stages or severe cases, ulceration and gangrene.
Grade 1, mild	Cool extremity with few symptoms but steal demonstrable by flow augmentation with access occlusion.
Grade 2, moderate	Intermittent ischemia only during dialysis/claudication.
Grade 3, severe	Ischemic pain at rest/tissue loss.
TCVC access outcome	Examples
Infectious complications	Catheter exit site infection, tunnel infection, bacteremia.
Non-infectious complications	Catheter malposition, mechanical dysfunction, catheter migration, venous thrombosis, pneumothorax, heamothorax, arterial puncture.

Abbreviations: AV, arteriovenous; TCVC, tunneled central venous catheter.