ORGAN PRESERVATION AND PROCUREMENT

A. Kanwar¹, S. Stamp², C. Wilson¹, M. Reddy¹, C. Ray¹, H. Wyrley-birch¹, B. Shenton², A. Cunningham³, N. Carter³, D. Talbot^1
1Liver / Renal Transplantation, Freeman Hospital, Newcastle upon Tyne hospitals, NHS trust, Newcastle upon Tyne/UNITED KINGDOM, ², Newcastle University, Newcastle upon Tyne/UNITED KINGDOM, ³School Of Applied Sciences, University of Sunderland, Sunderland/UNITED KINGDOM

Body: Introduction: We aimed to evaluate a novel organ preservation solution with low K⁺ concentration using aortic ring baths in a rodent Non-Heart Beating Donor model. Methods: In Non-heart beating rats, after an hour of primary warm ischemia abdominal aorta was flushed with streptokinase(3500 IU). This was followed by intra-arterial cooling with a mixture of cold HTK(20 ml) and heparin(200U). Aorta was dissected out and 3-5mms thoracic aortic sections were cold stored(24hrs) in three different preservation solutions. Normal saline was used as a control. Of the three preservation solutions, one was the standard kidney preservation solution (KPS1, K⁺25mmol/l). The other two contained low K⁺ levels. One was a KPS1 variant (SK-5, K⁺5mmol/l), and the other was a non-renal Organ Preservation Solution (nrOPS, K⁺6mmol/l). After cold storage the aortic rings were stretched between two points, one containing a pressure transducer probe. The rings were then immersed in 10mls of Krebs-Henseleit solution and gassed with carbogen(95% Air / 5%CO₂) at 37^oC and 7.4+/-0.5 pH. Graduated doses of phenylepherine and acetylcholine were added to measure the contraction and endothelium dependant relaxation. Contraction/relaxation profiles of the solutions were compared using ANOVA(two factor within subjects) with Bonferroni. Results: 10 male wistar rats provided aortic rings to allow simultaneous comparisons between solutions. The maximal mean contraction was higher for SK-5(71%) and KPS1 (73%) in comparison to nrOPS(25%)(p<0.05) and control(5%)(p<0.001). Overall relaxation (endothelial dependant) was significantly different within the groups; F(3,27)=9.353;p<0.001. SK5 produced a superior relaxation profile(end relaxation 20.2%) (p<0.05) as opposed to either nrOPS(end relaxation 1.5%) or control(end relaxation -6.9%). KPS1 had a relaxation profile in between SK5 and nrOPS, but it wasn’t significantly different. Conclusion: Therefore endothelial function would appear to be slightly better with SK5 as opposed to more standard K⁺ levels in normal KPS1.

Disclosure: All authors have declared no conflicts of interest.