Heterotopic Transplant of an Isolated Rat Heart Preserved for 72 h in Perfluorocarbon with CO2

Preservation by desiccation of isolated rat hearts for 48 hours using carbon monoxide (PCO = 4,000 hPa) and oxygen (PO(2) = 3,000 hPa)

It is currently said that CO has anti-inflammatory and antiapoptosis effects and it has attracted attention as a medical gas. We used CO for rat hearts and conducted a preservation experiment. We isolated rat hearts, placed them into a specially made chamber, filled the chamber with a gas mixture of PCO (4,000 hPa) and PO(2) (3,000 hPa), and preserved the hearts in a refrigerator at 4°C for 48 h. We then performed a heterotrophic transplantation on the neck of each recipient rat and resuscitated the preserved hearts. We herein report our findings.

The two layer method does not improve the preservation of porcine kidneys

BACKGROUND

The Two layer method (TLM) has been extremely successful in the preservation of the pancreas. However, this has not been thoroughly investigated in other organs or in clinically relevant large animal models. The aim of this study was to assess the effects of TLM in a large animal model of kidney preservation.

MATERIAL/METHODS

Porcine kidneys were retrieved after 10 minutes of warm ischaemic injury and flushed with 300 ml UW solution at 4°C. Kidneys were then either placed in University of Wisconsin solution (UW) or TLM using pre-oxygenated perfluorodecalin and UW. Kidneys were stored for 18 hours at 4°C then reperfused with oxygenated autologous blood to assess renal function.

RESULTS

Renal blood flow (RBF) was significantly lower and intra-renal resistance (IRR) higher in TLM compared to UW group [Area under the curve (AUC) RBF, UW; 427±168 vs TLM; 247±55 ml/min/100g.h; P=0.041, AUC IRR, UW; 7.7±2.2 vs TLM; 10.5±1.9 ml/min/mmHg; P=0.041]. Levels of creatinine clearance (CrCl) were significantly lower in TLM group [AUC CrCl, UW; 1.8±1.0 vs TLM; 0.6±0.4 ml/min/100 g.h; P=0.034]. Levels of lipid peroxidation were significantly lower in TLM group [8-isoprostane/Cr ratio 3h; UW 3338±896 vs TLM 2072±886 pg/ml/mmol/L; P=0.04]. Levels of total nitric oxide were significantly higher in TLM group (P=0.009).

CONCLUSIONS

TLM did not improve the preservation condition of porcine kidneys. Furthermore, there appeared to be increased inflammation, endothelial injury and reduced renal function compared to preservation with UW. Further experimental work is needed to determine the role of PFC in kidney preservation.

The role of perfluorocarbon in organ preservation

Perfluorocarbons (PFCs) are inert solutions that have a high capacity for dissolving oxygen. There has been a continuing level of research into the delivery of oxygen during solid organ preservation with the use of PFCs. The one- and two-layer methods have been used as static storage techniques, proving particularly successful for pancreas preservation. They can also be formulated as an emulsion for continual perfusion or as a simple flush solution. The success of PFCs in organ preservation seems to be somewhat organ and species dependant, and further experimental evidence is needed to establish their application.

Seventy-two-hour preservation, resuscitation, and transplantation of an isolated rat heart with high partial pressure carbon monoxide gas (PCO = 400 hPa) and high partial pressure carbon dioxide (PCO(2) = 100 hPa)

The cardiac cavity of an isolated rat heart was filled with a Krebs-Henseleit (KH) solution, and the heart was hung in a high-pressure chamber. After the high-pressure chamber had been filled with a mixed gas (PCO = 400 hPa, PCO(2) = 100 hPa, PO(2) = 900 hPa, PHe = 5600 hPa) and preserved for 72 h, we performed a cervical ectopic heart transplantation on a recipient rat and resuscitated the preserved heart. This is the first incidence in the world of a mammalian organ having been successfully preserved and resuscitated after 72 h via a desiccation method.

Study on the preservation with CO (PCO = 200-2,000 hPa), resuscitation, and heterotopic transplantation of an isolated rat heart

In this experiment, CO was used as a gas mixture in a reversible relationship with O(2). CO was added in a gas form mixed with O(2). An isolated donor rat heart was obtained, exposed to a gas mixture such as PO(2) = 1,800 hPa and PCO = 200 hPa, and PO(2) = 1,000 hPa and PCO = 1,000 hPa in a 2 ATA high-pressure chamber and preserved in a refrigerator at 4 degrees C. This report demonstrates that significant reproducibility has been verified. The heart was removed from the refrigerator 24 h later and heterotopic heart transplantation was performed in the right neck of a recipient rat and the pulsating of the transplanted heart was detected by an electrocardiogram.

A Study on the Perfusion Preservation, Resuscitation, and Transplantation of a Rat Heart Isolated for 96 Hours

Krebs-Henseleit (KH) solution was used to fill the heart chamber of an isolated rat heart before it was immersed in perfluorocarbon (PFC), which is an inert fluid. A gas mixture (PCO2 = 150 hPa and PO2 = 850 hPa) was then aerated at a constant rate into the PFC solution, and the isolated heart was thereafter preserved for 96 h with KH solution perfused continuously at a rate of 0.1 ml/h from the aorta of the isolated heart through a cannula. After preservation, the preserved heart was heterotopically transplanted into the neck of a recipient rat and then it was resuscitated. Using this method for preserving mammalian organs, we attained reproducibility after perfusion preservation for 96 h.