Helium perfusion appears to offer an improved technique for the preservation of whole body organs.
A group of investigators in Montreal told the society for Cryobiology that preliminary trials with canine kidneys indicate helium perfusion is a "promising new approach" to some of the major problems inherent in conventional external freezing techniques.
The new technique employs cooled and warmed helium to produce uniform freezing and thawing of inner and outer organ tissues.
In their earlier experiments, I.J. Bickis, PhD, and I.W.D. Henderson, MD, Montreal General Hospital, found that perfusing kidneys with DMSO, freezing them slowly in liquid nitrogen freezers, and later thawing the organs in water baths caused a cracking of the kidney surface tissue. This mechanical damage is due to the freezing expansion of inner tissues which occurs after outer layers are frozen.
During Freezing
To overcome this problem, they began immersing kidneys in a container of perfusion fluid