Systematic review of techniques and devices used to avoid warm ischemia time injury during kidney transplantation

The lack of a reliable and reproducible technique to ensure a constantly low temperature of the graft during kidney transplantation (KT) may be a cause of renal nonfunction. The aim of this review was to assess all the methods and devices available to ensure hypothermia during vascular anastomosis in KT.

A literature search was conducted through May 2022 using PubMed/Medline, Cochrane Library, Embase and Web of Science databases. Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines were followed to identify eligible studies. The review protocol was registered on PROSPERO (CRD42022326550).

A total of 20 studies reporting on four hypothermia techniques met our inclusion criteria. Simple instillation of cold serum is not sufficient, the graft reaching up to 33 ℃ at the end of warm ischemia time (WIT). Plastic bags filled with ice slush have questionable efficiency. The use of a gauze jacket filled with ice-slush was reported in 12/20 studies. It ensures a graft temperature up to 20.3 ℃ at the end of WIT. Some concerns have been linked to potentially inhomogeneous parenchymal cooling and secondary ileus. Novel devices with continuous flow of ice-cold solution around the graft might overcome these limitations, showing a renal temperature below 20 ℃ at all times during KT.

The gauze filled with ice slush is the most common technique, but several aspects can be improved. Novel devices in the form of cold-ischemia jackets can ensure a lower and more stable temperature of the graft during KT, leading to higher efficiency and reproducibility.