RESUSCITATION AND RECOVERY OF HYPOTHERMIC, 

 SUPERCOOLED AND FROZEN MAMMALS 



R. K. ANDJUS, J. E. LOVELOCK and A. U. SMITIi 



(This subject was presented to the Conference by a sound fihn entitled "Resuscitation of 

 Hypothermic, Supercooled and Frozen Mammals" made at the National Institute for Medical 

 Research, London, under the supervision of Drs. Andjus, Lovelock and Smith. There follows 

 a summary of this film written by Dr. Smith and addenda furnished by Drs. Smith and Andjus. 

 The floor discussion which took place after the showing of the film follows the addenda.) 



SUMMARY OF SOUND FILM 



The film opened with an introduction by Dr. Parkes. He said that previous fihns 

 made in his Division on the effects of low^ temperatures dealt with individual cells 

 and small pieces of tissues and with the use of glycerol to protect them from the 

 otherwise fatal effects of freezing to, thawing from, and long-term preservation at 

 — 79° C, the temperature of solid CO,. This work had naturally made him and his 

 colleagues wonder how far they could go with the whole animal. Two very obvious 

 questions had arisen : first, how to stop the heart beat and respiration by reducing 

 body temperature in the range above zero in such a way as to permit reanimation on 

 warming ; second, what would happen to the animals when the body temperature fell 

 below zero and when the body water began to crystallize out as ice. Dr. Parkes went 

 on to say that at this point in their cogitations his staff had been fortunate in being 

 joined by Dr. Andjus, of the University of Belgrade, who had been working on 

 hypothermia in the rat at body temperatures down to zero, and who appeared to 

 have solved the first of the two problems. Dr. Parkes then introduced Dr. Andjus 

 who was doing an experiment. 



Dr. Andjus then showed a normal rat being enclosed in a 2 litre jar which was 

 placed in the refrigerator at +2° C. He explained that the concentration of oxygen 

 would gradually fall while the expired carbon dioxide would accumulate and that, 

 as a result, the animal would itself cool down in the cold environment. Two hours 

 later Dr. Andjus took the jar out of the refrigerator and demonstrated that the rat 

 was unconscious and flaccid, and in a state of cold narcosis which could be used for 

 surgical operations. The deep body temperature, recorded from a thermometer 

 inserted into the colon, was 18° C. Electrocardiographic electrodes were then at- 

 tached to record the heart beat both audibly and with a pen recorder. At 18° C. the 

 rhythm was regular but very slow for the rat. The animal was then prepared for 

 further cooling. It was thoroughly wetted with cold water and placed in a dish 

 containing crushed ice, and the entire body, except for the nostrils, covered with 

 crushed ice. Icy water was then added to fill the air spaces. Respirations were re- 

 corded by means of a rubber tube leading from the nostrils to a Marie tambour 

 with a lever which wrote on a smoked drum. The last breath was taken when the 

 deep body temperature had fallen just below 15° C. Soon after cessation of breath- 

 ing the heart stopped beating. This was demonstrated by means of the electro- 

 cardiogram. The rat was left for one hour without breathing, with its deep body 

 temperature dropping rapidly at first and then more gradually. By the end of the 



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