PRESERVATION OF ORGANS FOR TRANSPLANTATION 
Theodore I. Malinin* 
Simple hypothermia is the most commonly used 
method of preserving organs for clinical transplants. 
This method, despite its simplicity and low cost, has the 
disadvantage of not offering functional preservation for 
more than 12-24 hours. Preservation of organs for 
longer periods has many advantages. These include 
adequate immunological matching, selection and prep- 
aration of donors, and performance of the operation 
under other than "emergency conditions." The existing 
practical method of extracorporeal storage of whole 
organs for about 72 hours is hypothermic perfusion. 
Perfusion is also necessary for the delivery of cryo- 
protective agents to the organs which are to be pre- 
served by freezing, which appears to be the most feasi- 
ble method for prolonged organ storage. Many attempts 
have been made to develop procedures for freeze-preser- 
vation of complex organs. None of these, so far, has 
produced organs which would sustain the life of exper- 
imental animals after transplantation. The difficulty 
with obtaining the desired results with freezing seems 
to lie not necessarily with the freezing of individual 
cells, but with the freezing of large masses of organized 
tissues. The delivery of cryoprotective agents in a 
sufficient concentration appears to be the main limiting- 
factor in freezing attempts. This may be accounted for 
by the injury produced in the microvasculature by the 
introduction of cell-free solutions and high concentra- 
tions of cryoprotective substances which are potentially 
toxic. Organ perfusion with cell-free media requires the 
initial removal of the residual blood from the vascular 
tree of the perfused organ and its replacement with 
solutions which can deliver nutrients and oxygen to the 
tissue and remove metabolic waste products. The addi- 
tion of red blood cells to the perfusion fluid has met 
with disappointing results, since the erythrocyte-con- 
taining solutions did not increase the extracorporeal life 
span of the perfused organ. Perfusion solutions which 
so far have provided organ survival in artificial environ- 
ment include freeze-thawed and filtered blood plasma 
and hypertonic chemically-defined media. By use of these 
solutions the life span of perfused kidneys has been ex- 
tended to five days and hearts to five-seven days. The 
damage sustained by organs preserved by these pro- 
cedures has not been adequately studied and docu- 
mented. Structural and functional alterations have been 
* Departments of Surgery and Pathology, University of Miami 
School of Medicine and Surgical Service, Veterans Administration 
Hospital, Miami, Florida. 
found in hearts, kidneys, and lungs subjected to artificial 
perfusion. 
INTRODUCTION** 
Transplantation of organs in experimental 
animals has been performed routinely in many 
surgical laboratories since the demonstration by 
Carrel in 1910-11 of the practicality of canine 
renal autotransplantation.^- Curiously, the 
problem of the extracorporeal preservation of 
organs intended for transplantation presented 
itself concomitantly with that of the surgical 
technique of vascular anastomosis. In the afore- 
mentioned experiments, reimplanted kidneys 
were perfused with and stored in Locke's solu- 
tion for 50 minutes. The basic technique of or- 
gan preservation has not changed appreciably 
in the ensuing years. Short-term preservation 
still depends either on simple hypothermia or 
on a combination of hypothermia and perfusion. 
Long-term preservation of any complex organ 
in a viable state has not been accomplished thus 
far. 
The dog remains the experimental animal 
used for the majority of organ preservation 
studies.'' Some experiments have been per- 
formed on pigs.^ The use of primates for the 
same purpose has gained prominence in the last 
decade.^ '' Among small, inexpensive animals the 
rabbit has been employed for studies on renal 
preservation.'^ 
Until relatively recently, kidneys used for 
transplantation experiments were preserved al- 
most exclusively by hypothermia. In a dog, this 
method of preservation can provide a period of 
storage up to approximately 24-hours. The re- 
sults with this method of storage, as applied 
to human kidneys, were likewise apparently 
satisfactory providing the total ischemic period 
** Supported by the Office of Naval Research Contract N00014-67- 
A-0016. 
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