Current Outcomes and Indications for Cryopreserved Vein Allografts in Hemodialysis Access Surgery

Potential Complications With Cryopreserved Cadaveric Veins in Arteriovenous Loop Formation for Head and Neck Microvascular Reconstruction

ABSTRACT

Vessel depletion in the head and neck from radiation or previous surgical intervention adds to the operative complexity by limiting reconstructive options. Arteriovenous (AV) loop vascular grafts provide a conduit to bypass these nonviable local vessels to provide adequate blood flow. In certain situations, autologous donor vascular options are deficient or not readily available for creation of the AV loop. Cadaveric vein grafts provide an alternative option in these circumstances, but the efficacy and safety has not yet been delineated. In this study we discuss our experience utilizing cryopreserved cadaveric vein grafts for AV loop creation in head and neck reconstruction. In our initial cohort we aim to elucidate potential challenges and complications associated with the use of cadaveric vein grafts.

Cryopreserved venous allograft is an acceptable conduit in patients with current or prior angioaccess graft infection

OBJECTIVE

The durability of cryopreserved allograft has been previously demonstrated in the setting of infection. The objective of this study was to examine the safety, efficacy, patency, and cost per day of graft patency associated with using cryopreserved allograft (vein and artery) for hemodialysis access in patients with no autogenous tissue for native fistula creation and with arteriovenous graft infection or in patients at high risk for infection.

METHODS

Patients implanted with cryopreserved allograft for hemodialysis access between January 2004 and January 2014 were reviewed using a standardized, multi-institutional database that evaluated demographic, comorbidity, procedural, and outcomes data.

RESULTS

There were 457 patients who underwent placement of cryopreserved vein (femoral: n = 337, saphenous: n = 11) or artery (femoral: n = 109) for hemodialysis access at 20 hospitals. Primary indications for allograft use included high risk of infection in 191 patients (42%), history of infected prosthetic graft in 169 (37%), and current infection in 97 (21%). Grafts were placed more frequently in the arm (78%) than in the groin, with no difference in allograft conduit used. Mean time from placement to first hemodialysis use was 46 days (median, 34 days). Duration of functional graft use was 40 ± 7 months for cryopreserved vein and 21 ± 8 months for cryopreserved artery (P < .05), and mean number of procedures required to maintain patency at follow-up of 58 ± 21 months was 1.6 for artery and 0.9 for vein (P < .05). Local access complications occurred in 32% of patients and included late thrombosis (14%), graft stenosis (9%), late infection (9%), arteriovenous access malfunction (7%), early thrombosis (3%), and early infection (3%). Early and late infections both occurred more frequently in the groin (P = .030, P = .017, respectively), and late thrombosis occurred more frequently with cryopreserved artery (P < .001). Of the 82 patients (18%) in whom the cryopreserved allograft was placed in the same location as the excised infected prosthetic graft, 13 had infection of the allograft during the study period (early: n = 4; late: n = 9), with no significant difference in infection rate (P = .312) compared with the remainder of the study population. The 1-, 3-, and 5-year primary patency was 58%, 35%, and 17% for cryopreserved femoral vein and 49%, 17%, and 8% for artery, respectively (P < .001). Secondary patency at 1, 3, and 5 years was 90%, 78%, and 58% for cryopreserved femoral vein and 75%, 53%, and 42% for artery, respectively (P < .001). Mean allograft fee per day of graft patency was $4.78 for cryopreserved vein and $6.97 for artery (P < .05), excluding interventional costs to maintain patency.

CONCLUSIONS

Cryopreserved allograft provides an excellent conduit for angioaccess when autogenous tissue is not available in patients with current or past conduit infection. Cryopreserved vein was associated with higher patency and a lower cost per day of graft patency. Cryopreserved allograft allows for immediate reconstruction through areas of infection, reduces the need for staged procedures, and allows early use for dialysis.