Introduction
Kidney transplantation (KT) has become the treatment of choice for paediatric end-stage renal disease [1]. Nevertheless, in comparison to adults, the small caliber of the vessels and the common size-mismatch between donors and recipients can predispose to vascular complications including allograft thrombosis. The latter may affect up to 10% of KTs and account for 35% of allograft losses in the first year [2]. Prompt recognition and treatment is clearly essential for the preservation of the allograft.
Vascular complications have no specific clinical or biochemical signs allowing for early diagnosis. Doppler-ultrasonography (DUS) and renal scintigraphy are reliable tools to assess allograft perfusion [3], but do not allow for continuous monitoring of the allograft and can miss early diagnosis, even if performed with a strict schedule in early follow-up of KT [4].
Transcutaneous near-infrared spectroscopy (NIRS) allows for non-invasive, real-time, continuous monitoring of regional oxygenation of the haemoglobin (rSrO2), which is an indirect measure of the blood flow and the metabolic state, of tissue placed deeper beyond the skin. Several clinical studies have tested the use of NIRS for monitoring cerebral and somatic perfusion in intensive care units [5] and the viability of soft-tissue flaps [6]. Recently, it has been proposed for the surveillance of allograft perfusion too [7].
A systematic search of literature was performed, aiming to identify the current evidence on the in vivo application of NIRS for the monitoring of allograft perfusion. The findings might be useful for future research to implement the large-scale use of NIRS.