Plasma and tissue levels of free oxygen radicals in recipients of kidneys from non-heart-beating donors: does recipient pretreatment with antioxidant drugs make sense? An experimental study in pigs

Ventilation and Haemodynamic Indicators in Spontaneously Breathing Pigs under General Anaesthesia

The aim of this study was to obtain ventilation and haemodynamic data of healthy piglets under general anaesthesia for future patho-physiological experimental studies. A total of 34 domestic piglets of the Czech Black Pied (Přeštice) breed were used in the study. The animals (male to female ratio 8 : 9) were six weeks old and their average body mass was 22 kg. A general anaesthetic (fentanyl and azaperon) was introduced via a pulmonary artery catheter and the spontaneously breathing animals were monitored for 60 min. Cardiac output and haemodynamic indicators were established using intermittent pulmonary artery thermodilution. Blood gas data were deduced using fan dynamic parameters of ventilation and ventilation indices. The study yielded reliable data of dynamic lung indicators (p < 0.05); e.g. the tidal volume 6.00 ± 0.82 ml/kg, hypoxemic index 350.47 ± 42.50 mmHg, lung compliance 0.63 ± 0.12 ml/cmH2O/kg, and haemodynamic indicators (p < 0.01) such as cardiac output 2.12 ± 0.75 l/min, pulmonary vascular resistance 3.92 ± 0.52 and systemic vascular resistance 15.8 ± 6.81 Woods units. Reliable data regarding lung dynamics, cardiac output, preload and afterload of both heart ventricles in spontaneously breathing healthy piglets under general anaesthesia were achieved.

Effects of Perfusion Solutions on Kidney Ischemia-Reperfusion Injury in Pigs

During ischemia-reperfusion, free oxygen radicals which directly affect renal cells may cause delayed graft function. We investigated whether there was a difference regarding antioxidant enzyme content between use of Ringer's lactate (RL) versus University of Wisconsin (UW) perfusion solutions in kidney transplantation. Ischemia was achieved by clamping the renal pedicle for 20 minutes followed by perfusion with either solution for 20 minutes and reperfusion for another 20 minutes. A parenchymal biopsy was taken before and after the ischemia, perfusion, and reperfusion (IPR) process. The levels of superoxide dismutase (SOD), glutathione peroxidase (GPx), and malondialdehyde (MDA) were investigated in the biopsy specimens. We used paired t tests within groups and t tests for comparisons between groups. The results were expressed as mean values +/- SEM with P < .05 accepted as statistically significant. After IPR, SOD, GPx, and MDA were decreased in all groups: only GPx (P = .001) and MDA (P = .04) for the RL group and SOD (P = .001) and MDA (P = .05) for the UW group were statistically significant. In the control group, we did not observe any difference (P > .05). Comparisons between groups did not reveal differences (P > .05). In our study, no difference was observed between RL and UW regarding their effects on antioxidant enzymes following renal I/R injury in pigs. More investigations are needed to evaluate graft function in this setting.

Can ischemia-reperfusion syndrome in transplanted kidneys procured from non–heart-beating donors be influenced by adding selenium into the reperfusion solution? an experimental study

Ischemia-reperfusion syndrome significantly influences the function of a kidney transplanted from a non-heart-beating donor (NHBD). An animal model of NHBD was used to monitor the influence of the exogenous addition of selenium in the perfusion solution (HTK, Custodiol) on the generation of free oxygen radicals between 0 and 120 minutes after transplantation of the NHBD organ. During this interval, the malondialdehyde concentration, an indicator of free oxygen radicals in the venous blood of the transplanted kidney, significantly decreased. The augmentation of the anti-oxidant capacity of the preservation solution might represent a possible improvement in the function of kidneys transplanted from NHBDs.

Can the ischemia-reperfusion syndrome in transplanted kidneys procured from non-heart-beating donors be influenced by adding selenium into the reperfusion solution? An experimental study

The ischemic-reperfusion syndrome significantly influences the function of a kidney transplanted from a non-heart-beating donor (NHBD). The animal model of a NHBD was used to monitor the influence of exogenous addition of selenium into the reperfusion solution (HTK, Custodiol) with respect to the formation of free oxygen radicals at 0 to 120 minutes after the NHBD transplantation. This maneuvers produced a statistically significant decrease in malondialdehyde concentration, an indicator of free oxygen radicals in the venous blood of the transplanted kidney. The augmentation of the antioxidative capacity of the preservation solution might be a possible route to improve the function of kidneys transplanted from NHBDs.