REVIEW AND APPRAISAL OF PARTS I AND II 



STEVEN M. HORVATH 



It is the reviewer's impression that while valuable information on the hypo- 

 thermic state has been presented in this monograph, there is considerable difficulty 

 in evaluating many of the contributions. Much of the confusion is the result of 

 widely divergent techniques and conceptual approaches. As Dr. Frank Fremont- 

 Smith has often said during the Macy Conferences, "Have you duplicated the 

 experiment? Haven't you really performed another experiment?" These statements 

 apply to most of the experiments on hypothermia. 



The variables that have existed in the experimental and applied aspects of hypo- 

 thermia can be summarized as follows : 



I. Physiological condition of the experimental animal* 



A. Presence or absence of abnormal physiological states, such as cardiac 

 or vascular defects, hepatic damage, etc. 



B. Nutritional status 



C. Intact animals or surgically induced variations, i.e., open chest prepara- 

 tions, catheterizations, exposed vessels, etc. 



II. Cooling procedures 



A. Rate of depression of body temperature 



B. Control of protective mechanisms against reduction of body tempera- 

 ture, (e.g. presence or absence of shivering) 



C. Depth to which cooling is carried 



1. Surgical hypothermia (28° -26° C.) 



2. Experimental hypothermia (down to —4° — 6° C.) 



D. Duration of reduced body temperatures 



E. Stability of reduced body temperatures both in terms of time and 

 extent 



III. Ventilation of the organism 



A. Spontaneous vs. controlled 



B. Adequacy of ventilation 



IV. Rewarming and resuscitation of the hypothermic animal 



A. Spontaneous (slow) vs. artificial (slow or fast) 



B. Local vs. general 



V. Expression of the results obtained 



A. Use of the rectal temperature as the criterion of the thermal state 



B. Linear vs. non-linear temperature-dependent relationships 



C. Interreaction (relationship?) of cellular activity to organ activity to 

 activity of the total organism 



Our concepts of the degree of hypothermia tolerated by the homoiothermic ani- 

 mal received a rude shock from the experiments of Andjus and Smith and of Gol- 



* This term is being used here to refer to all nianinialian forms utilized, i.e., man, monkey, dog, 

 rat, etc. 



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