Preserving and perfusing the allograft pancreas: Past, present, and future.

The concept of organ preservation by perfusion dates back to the mid-19th century. Innovations since then have included temperature regulation, perfusion fluid composition and various pumping systems. Advances made in liver, heart and kidney machine preservation are now contributing to increased graft utilisation, assessment of graft viability and potentially improved graft survival. Pancreas transplantation has not benefitted to the same extent from the application of perfusion technology, although the need is just as great. This overview reviews current pancreas specific preservation techniques. We explore concepts, which include static cold storage, use of preservation solutions, the 'two-layer method', and machine perfusion. We also discuss ideas for future development. Narrative review of literature from inception to December 2017 using OVID interfaces searching EMBASE, Google Scholar, and MEDLINE databases. All studies relevant to pancreas perfusion and preservation were examined for clinical relevance with no exclusion criteria. Conference papers and presentations were also reviewed and included where appropriate. The application of recent advances in understanding in ischaemia-reperfusion as well as technical developments in machine preservation Ischaemia-reperfusion have the potential to improve organ utilisation, viability and outcome.

Neoaortic Xenoprosthetic Grafts for Treatment of Mycotic Aneurysms and Infected Aortic Grafts.

BACKGROUND: There is no international consensus regarding the optimum management of infected aortae (mycotic aneurysms, infected aortic grafts). Neoaortoiliac reconstruction has advantages over extra-anatomical bypass grafting; however, the use of autologous vein is associated with venous hypertension and compartment syndrome, alternatively cadaveric homografts are associated with high rates of perianastomotic hemorrhage, limb occlusion, and pseudoaneurysm. Arterial repair using xenoprosthetic patches is associated with lower infection rates compared to the use of prosthetic material. The aim of this case series and literature review is to report the use of xenoprosthetic bovine biomaterial for neoaortic repair of mycotic aneurysmal disease and infected aortic grafts. METHODS: Patients with evidence of infected aortic grafts or mycotic aneurysms who were suitable for open aortic surgery were included. Following removal of the graft/excision of the aneurysmal sac, a 10 × 16 cm XenoSure Biologic Surgical Patch (LeMaitre, Germany) was rolled into a tube, or bifurcated tube graft, and secured with prolene sutures. Proximal and distal anastomoses were conducted as per standard aortic anastomoses. Patients were continued on long-term antibiotics and surveyed with computerized tomography at 1, 3, 6, and 12 months. RESULTS: Six patients underwent bovine aortic repair between 2013 and 2015: an infected Dacron aortobi-iliac graft causing iliac pseudoaneurysm, an infected Dacron aortic graft from open repair later relined with endovascular stent graft, a mycotic iliac aneurysm, and 3 mycotic aortic aneurysms. All were treated with bovine reconstructed aortic grafts or patches. Patients had a median age of 69.5 years (range 67-75), with perioperative and 30-day mortality of 0%. Median follow-up was 13 months (range 2-23). Postoperative contrast-enhanced computed tomography revealed no evidence of infection at the operative site in all patients. Freedom from reinfection and reintervention was 100%. CONCLUSIONS: Xenoprosthetic (bovine) neoaortic grafts are an alternative method to treat infected aortae with excellent short-term freedom from infection and reintervention. Optimum duration of postoperative antibiotic therapy remains undetermined. Further cases and longer follow-up are required to determine the true efficacy of this technique.