HYDROTIIERAPY 859 



mals are always subject, decrease their metabolism, protein disintegration 

 rises above normal, as shown on dogs (Lepine and Flavard ; Dommer) 

 and also on men whose temperatures were reduced to 32 (Forrnanek(&)). 

 On nitrogen distribution following cold fresh-water baths, the data of 

 Schilling are considered reliable; he found a marked increase in ammonia 

 excretion not associated with a simultaneous increase in nitrogen elimina- 

 tion. The findings of Krauss showed an increased acidity after cold baths 

 and temporary albuminuria may often appear after prolonged cold baths 

 (Araki(fr) ; Ilem-Picci). Under normal bathing conditions as employed 

 in hydrotherapy, short cold baths cause an increase in metabolism of non- 

 nitrogenous materials only, the energy derived therefrom being used 

 for heat production and for the increased muscular work which this neces- 

 sitates. Any energy changes due to the cooling itself are obscured by the 

 energy expended in muscular activity and it is probable that both of these 

 are influenced somewhat by the adaptive power of individuals to repeated 

 heat deprivation, as well as by their physical characteristics and state 

 of nutrition. Whether the additional heat production necessitated by cold 

 baths takes place in the absence of muscular activity need not lie discussed 

 at this time since under ordinary conditions there is no restraint upon 

 movement. In experiments on men it was shown that the cooling of the 

 body in cold baths was accompanied by a rise in respiratory metabolism 

 only where involuntary shivering occurred (Silber). It must be expected 

 that even in the absence of such movement the additional work performed 

 by the respiratory muscles, the heart and the vasomotor system provides 

 some heat as a by-product. 



The redistribution of blood under local or general application of cold 

 is considerable (Hewlett, van Z. and M.) and organ activity and local 

 metabolism are thereby modified in so far as they are dependent on blood 

 supply. Also, since cold can penetrate more deeply than heat, it is possi- 

 ble to limit its effect on individual organs more accurately than is the 

 ease with heat. The general effects of cold baths on the circulatory 

 system involve the many hydrostatic as well as reflex vascular factors 

 affecting the bulk and the flow of the blood, and are therefore very com- 

 plex. After a cold bath the pulse is slowed (Beck and Dohan), the volume 

 pulse and minute volume are increased (Schapals), arterial blood pressure 

 is often increased and venous pressure decreased (Winternitz(e) ; Edge- 

 combe and Bain), the extent probably depending in part on internal com- 

 pensations and antagonisms (Muller(a)). According to Strassburger 

 systolic blood pressure during a cold bath may show two or three phases, a 

 rapid rise, the more rapid as the bath is colder, a decrease (corresponding 

 to the ''reaction' 7 ) and a final increase, depending on the balance between 

 the heart action and the condition of the capillaries. After the bath there 

 is a fall in blood pressure, usually under the original level. The transient 

 increase in blood pressure has been given as the cause of the diuresis tern- 



