Experimental renal preservation by normothermic resuscitation perfusion with autologous blood

Normothermic perfusion (NP) has the potential to improve metabolic support and maintain the viability of ischaemically damaged organs. This study investigated the effects of NP compared with current methods of organ preservation in a model of controlled non-heart-beating donor (NHBD) kidneys.

Porcine kidneys (n = 6 in each group) were subjected to 10 min warm ischaemia and then preserved as follows: 2 h cold storage (CS) in ice (CS2 group), 18 h CS (CS18 group), 18 h cold machine perfusion (CP group) or 16 h CS + 2 h NP (NP group). Renal haemodynamics and function were measured during 3 h reperfusion with autologous blood using an isolated organ perfusion system.

Increasing CS from 2 to 18 h reduced renal blood flow (mean(s.d.) area under the curve (AUC) 444(57) versus 325(70) ml per 100 g; P = 0.004), but this was restored by NP (563(119) ml per 100 g; P = 0.035 versus CS18). Renal function was also better in CS2, CP and NP groups than in the CS18 group (mean(s.d.) serum creatinine fall 92(6), 79(9) and 64(17) versus 44(13) per cent respectively; P = 0.001). The AUC for serum creatinine was significantly lower with CS for 2 h than for 18 h (mean(s.d.) 1102(2600) versus 2156(401) micromol/l.h; P = 0.001), although values in CP and NP groups were not significantly different from those in the CS2 group (1354(300) and 1756(280) micromol/l.h respectively). Two hours of NP increased the adenosine 3'-triphosphate : adenosine 3'-diphosphate ratio to a significantly higher level than the preperfusion values in all other groups (P = 0.046).

NP with oxygenated blood was able to restore depleted ATP levels and reverse some of the deleterious effects of CS.