Opposite Acute Potassium and Sodium Shifts During Transplantation of Machine Perfused Human Liver Grafts

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L.C. Burlage, L. Hessels, R. van Rijn, N. Karimian, A.C. Westerkamp, A.P.M. Matton, K. Reyntjens, I. Petzold, M.M.W. Nijsten, R.J. Porte

Chair(s): Drs. F.M. Molenaar

Thursday 9 march 2017

12:45 - 13:00h

Categories: Poster - Klinisch

Parallel session: Postersessie - Klinisch 5

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Background:
Acute rise of serum potassium levels during orthotopic liver transplantation (OLT) is mainly explained by the systemic entry of the high potassium-containing preservation fluid upon reperfusion, in which the donor graft is immersed during static cold storage (SCS). During end-ischemic hypothermic oxygenated machine perfusion (HMP), livers are flushed and perfused with a low potassium content solution prior to transplantation. The aim of this study was to examine the effect of end-ischemic oxygenated HMP on both in vivo and ex vivo cation shifts.

Methods:
During OLT, we compared serum potassium levels before and after reperfusion of the liver graft. Livers were transplanted either directly after SCS preservation (n=20) or after additional preservation for two hours via end-ischemic oxygenated HMP (n=10). All potassium levels were determined during both machine perfusion and transplantation. Additionally, potassium levels were determined in perfusate samples of livers that were discarded for transplantation.  Discarded livers underwent normothermic perfusion (NMP) either directly after SCS preservation (n=16) or after additional preservation for two hours via end-ischemic oxygenated HMP (n=6). Potassium administrations in any form as well as interventions that could have affected hyperkalemia were recorded.

Results:
In recipients who received a graft directly after SCS, the mean±SE potassium level rose by 0.27 mmol/L (from 4.43±0.12 to 4.70±0.17 mmol/L; P=0.174), while potassium level decreased by 0.76 mmol/L in the HMP recipients (4.65±0.17 to 3.89±0.31 mmol/L; P=0.003) during reperfusion. Acute potassium administration was required in 0 (0%) and 3 (30%) patients (p=0.030) respectively. Antihyperkalemic measures were performed in 8 (40%) SCS alone and 9 (90%) HMP patients (p=0.017). During HMP, potassium level increased  during the first 30 minutes and remained stable thereafter. Balance measurements confirmed considerable hepatic potassium release and sodium uptake during HMP. Similar potassium shifts were seen during both HMP and NMP of discarded livers.  

Conclusion:
Whereas hyperkalemia is anticipated directly after reperfusion during transplantation with conventionally preserved livers, HMP preservation induces ex vivo potassium release and frequently leads to hypokalemia after reperfusion. Anesthesiologists should be prepared for an unexpected potassium and sodium response in patients who receive a liver graft after HMP.