Distal perfusion during complex aortic arch procedure reduces kidney injury in newborn piglets at moderate hypothermia†.

Objectives: Complex aortic arch procedures in newborns require the most optimal perfusion strategy to prevent acute kidney injury and its consequences from developing. We performed a randomized comparison of the selective anterograde cerebral perfusion (SACP) and SACP with additional distal perfusion (SACP+DP) with moderate hypothermia in a neonate piglet model to generate better insights into renal tissue-specific injury due to the different perfusion strategies in newborns.

Methods: Newborn piglets (2.5-10 kg) were randomized to undergo cross-clamp for 60 min with either SACP (n = 9) or SACP+DP (n = 9) followed by 120 min of recovery. Renal biopsies were analysed for histomorphological changes and the induction of hypoxia-related factors. Kidney injury markers were analysed in piglet serum.

Results: Histomorphological analyses of renal biopsies after 120-min recovery showed comparable glomeruli area (P = 0.06), glomerular capsule space length (P = 0.25), proximal tubules cell height (P = 0.09) and diameters of proximal tubules (P = 0.23) between SACP and SACP+DP. hypoxia-inducible factor 1α nuclear translocation, a marker for oxidative stress, was higher in the glomeruli (P < 0.01) and proximal tubules (P = 0.05) in the SACP group compared to the SACP+DP group. Serum concentrations of neutrophil gelatinase-associated lipocalin were higher in the SACP group (100.3 ± 40.8 ng/ml) compared to the SACP+DP group (67.4 ± 19.3 ng/ml, P = 0.03).

Conclusions: Our neonate piglet study demonstrated higher oxidative stress in vulnerable nephron structures in renal tissue and higher serum neutrophil gelatinase-associated lipocalin concentrations with SACP compared to SACP+DP indicating that SACP+DP is more suitable to reduce renal insult induced by complex aortic arch procedures.