Evening star., 1952-01-11
PIexigIus-Mode Arteries
Produced for Grufts
Georgetown U. Experiments
Outlined by Dr.. HufnogeI
By Thomos z. Henry

Arteries made Of plexiglas which can
damaged sections in the body have been
produced at the Georgetown University
Medical Research Center here.
Thus far the gratis have been ex-
perimental and confined to dogs, but
there is no apparent reason why they
should not be successful with humans.
DR.. Charles Hufnagel told symposium
on blood-vessel gratis at the National
Institutes Of Health yesterday.
The artificial artery sections are made
precisely the size and shape Of the
natural arteries and can be fitted to
the individual. They are made of a
material which chemically is almost
completely inert. They are held in place
by nylon rings of a type invented by
DR.. Hufnagel, SO that no possibly
damaging sutures are necessary.
They will, DIR. Hufnagel said, be used
on the first human patients in the very
near future
In the animal experiments thus far
they have been employed chiefly for
gratis In the aorta. the principal artery
carrying blood from the heart. They
have been quite short. Hitherto there
has been considerable success with
ao1tal CRAFTS of actual human arteries
obtained from the dead.
For Adult Use Only.
DR.. Hufnagel is confident, he said,
that the artificial arteries will be equally
successful when used as CRAFTS for the
smaller arteries. such as in the leg, and
he has constructed them up to eight
inches long.
The only apparent limitation is that
they must be used in adults They OBJ
viously would be only of temporary value
during the period of growth when the
arteries are increasing in size If they
prove successful in humans they may
have considerable advantages over gratis
of actual arteries. They will never de-
generate. Tissue grows over them but
never inside. as is the case with natural
arteries.
DR.. Hufnagel also described the most
advanced methods now developed at
Georgetown for the preservation of
actual human or animal arteries for
long periods.
First they are plunged in liquid nj
trogen. which freezes them at temper
ature of 1856 below zero centigrade in
less than Is seconds This preserves
them alive otentially-immortal
When water is frozen there is a long
Stretchfrom zero centigrade to about 10
when it forms ice-that is, it SolidifleS
in crystals. These crystals break up the
tiny cells which are the units of life.
But below -70-posSibly the critical
point is considerably higher-water So
lidifieS into something like glass which
does no damage to cell tissue
All functions of life, of course, are
suspended. With extremely minute bits
Of tissue it has been possible to produce
esential immortality at some research
centers. How far this is achieved in
masses of tissue as big as sections of
arteries remains doubtful and the longest
period for which DR.. Hufnagel has kept
human arterial sections in this state of
suspended animation and then brought
them out successfully-in shape to be
used for grafts-is six months.
. Life-Saving Techniques.
After the quick bath in liquid nitrogen
the temperature is raised to approxi-
mately z centigrade. This can be main
tanned indefinitely with dry ice Before
they are used in surgery they must be
brought out of this temperature very
rapidly or fatal ice crystallization will
take place. If the temperature while
they are being preserved rises much
above Z, DR.. Hufnagal said. the arteries
are likely to be badly damaged. The
technique, he emphasized, still is far
from perfected. One of the difficulties
is the possible cracking of the glass;
as soon as 1t Is formed in the LIQUID
nitrogen bath.
The preserved arterial sections are
proving life savers in cases of organic
arterial disease, it was explained. They
have been used chiefly in heart sur
gerry.
Arterial gratis may prove Of great
Importance, other speakers pointed out,
in treatment of war wounds where ar
terles are severely damaged, and the
technique of preservation has advanced
to the point where artery banks can be
maintained at evacuation hospitals close
to the front lines. There would BE- a
plentiful supply of arteries obtainable
from those killed in action.
Experiments to determine the effects
OF length on arterial gratis in dogs we're
described by Dr. Brian Blades Of George
Washington University. Entire aortas,
about six inches long, were replaced with
complete success in many cases for
from three to eight months.
At the symposium. attended by the
Nations foremost experts in this field,
it was emphasized that artery and vein
CRAFTS still are on the frontiers of sur
gerry but that results to date are very
promising. This is exceptionally signifi-
cant since various types of arterial dis
ease are among the countrys chief
causes of death.