Performance of Renal Allografts Perfused With Verapamil-Treated Perfusion Solution

Verapamil has been used in perfusion solution to improve kidney performance, but evidence was anecdotal, and no research has been reported on recipient outcomes. Our organization began a program to evaluate Verapamil’s effect on pump performance, transplant rate, and recipient outcomes. One kidney in a pair was treated with Verapamil and one with standard perfusion. Donor inclusion criteria were age 18 or older and both kidneys were placed on the pump. The laterality of the treated kidney was changed every month to reduce bias. From January 1, 2020 to June 30, 2020, 88 kidneys were evaluated. Of those, 21 donors had both kidneys transplanted to different recipients, so for those 42 kidneys, recipient outcomes were evaluated. Small improvements in pump performance were observed in the Verapamil-treated kidneys and more were transplanted. No clinical differences were found in recipients between the Verapamil-treated and standard perfused kidneys. A larger cohort is needed to determine whether differences are significant.

Evaluation of the efficacy of a novel perfusion solution for normothermic ex vivo lung perfusion compared with Steen solution™ (animal experimental study)

Respiratory diseases, together with infectious complications and hereditary lung diseases, rank third in international mortality statistics. Today, lung transplantation is a recognized method of treating end-stage lung diseases. However, the number of transplant surgeries performed is not much. This is down to the high requirements on the condition of a potential lung donor and directly on the quality of the donor lung. This has significantly limited the number of optimal donors. Rehabilitation of donor lungs to optimal gas exchange indicators can be achieved and objectively assessed in the course of ex vivo lung perfusion (EVLP). The EVLP procedure is widespread in leading transplantation centers in Europe and North America. It allows to significantly expand the pool of donor lungs, thereby serving a greater number of patients in need of lung transplantation. The possibility of EVLP procedure using publicly available perfusion equipment was demonstrated. The optimized protocol fully demonstrated its reliability and efficiency. The developed perfusion solution had no statistically significant differences in comparison with the Steen SolutionTM, which in the future will serve as an alternative for EVLP procedure.

Cold Saline Perfusion before Ischemia-Reperfusion Is Harmful to the Kidney and Is Associated with the Loss of Ezrin, a Cytoskeletal Protein, in Rats

Background: Organ protection for transplantation is perfusion with ice-cold preservation solutions, although saline is also used in animal experiments and living donor transplantations. However, ice-cold perfusion can contribute to initial graft injury. Our aim was to test if cytoskeletal damage of parenchymal cells is caused by saline itself or by the ice-cold solution. Methods: F344 rat kidneys were flushed with cold (4 °C) saline, ischemic and sham kidneys were not perfused. In a separate set, F344 kidneys were flushed with saline or preservation solution at 4 or 15 °C. Ischemia time was 30 min. Results: Renal injury was significantly more severe following cold ischemia (CI) than after ischemia-reperfusion without flushing (ischemia/reperfusion (I/R)). Functional and morphologic damage was accompanied by severe loss of ezrin from glomerular and tubular epithelial cells after CI. Moreover, saline caused serious injury independently from its temperature, while the perfusion solution was more beneficial, especially at 4 °C. Conclusions: Flushing the kidney with ice-cold saline can cause more severe injury than ischemia-reperfusion at body temperature even during a short (30 min) ischemia. Saline perfusion can prolong recovery from ischemia in kidney transplantation, which can be prevented by using preservation solutions.

UPGRADE OF THE LANGENDORFF APPARATUS USING THE INFRARED THERMO-CONTROL SYSTEM AND AN INTELLIGENT HEATER

Biological experiments involving isolated organs and tissues demand precise temperature monitoring and regulation. An automatic temperature control system was proposed and optimised on real isolated swine hearts and the prototype is described in this work. The traditional Langendorff apparatus consists of a heart holder, a reservoir of perfusion solution flowing to aortic cannula and a heating bath allowing passive heat transfer to the reservoir of perfusion solution. The commercial infrared camera FLIR T62101 was added to this basic set-up and used for very precise monitoring of the temperature kinetic of the organ and connected with an electronic feedback loop, which allowed real-time and precise regulation of heat transfer from the heating bath to the perfusion solution and in turn indirectly to the heart tissue. This provides real time control and active regulation of the myocardial tissue temperature. The infrared camera was tested in several modes and several variants of detection were optimised for ideal measurement of the region of interest of the ex vivo organ. The kinetics of the temperature changes and temperature stability of the tissue were recorded and calibrated by external electronic thermometers (type Pt100, inserted in tissue). The time lapse from the hang-up of the hypo termed organ (30 °C) until optimal warming (37 °C) was less than eight minutes in the final instrument prototype. The final stability of the 37 °C tissue temperature was approved; the temperature fluctuation of left ventricle tissue was characterised as 36.8 ± 0.5 °C. This upgraded traditional instrument could be used in specific preclinical and clinical transplantation and analytical projects in future.

Gas Transport Characteristics of Hemocorrectors and Perfusates Based on Perfluorocarbon Blood-Substituting Emulsions

This review summarizes the data regarding the gas transport characteristics of hemocorrection and perfusates on the basis of low concentrated drugs nano-sized perfluorocarbonic 20% Perftoran (a blood substitute, it is allowed for clinical use in Russia), 20% Ftoremulsion III (an improved blood substitute, registered in Russia), 10-20% Perfusol (a perfusion solution for perfusion of the isolated heart), 20% Ftorem (a cardioplegic emulsion for surgeries on the stopped heart) used in the biomedical field. The compensation of blood loss using traditional plasma substitutes without the gas transport function or with low gas transport characteristics leads to a decrease in the oxygen capacity of the resulting mixture and subsequently to deterioration in the oxygen transport characteristics of blood. The synthetic gas-transport blood substitutes can be used in the treatment of various forms of ischemia, such as carbon monoxide poisoning. Furthermore, recent results regarding the mechanism of COVID19 infection indicate a possible use of the synthetic gas-transport blood substitutes in the treatment and therapy of COVID19 infected patients.