A Comparison between Dehydration from Salt Loss and from Water Deprivation.

In 1935 Kerpel-Fronius (1) demonstrated in rabbits that there are two distinct types of dehydration, depending upon whether the condition is associated with (1) a primary loss of salt or (2) a shortage of water not accompanied by a corresponding loss of salt. He pointed out that the former is characterized by circulatory disturbances, while the latter is characterized by thirst. In a later paper (2) Kerpel-Fronius referred to the two conditions as " Durstexsikkose und Salzmangelexsikkose " and emphasized the fact that in animals dehydrated by loss of salt the principal loss of fluid is from tfie extracellular portion, including the blood, whereas in thirsting animals the water loss is distributed among all fluid compartments of the body, including the large intracellular portion. It is our impression that most physicians, including ourselves, have not been sufficiently aware of this important distinction and its therapeutic implications. The present report concerns itself with a study of these two types of dehydration in normal human subjects. The first two experiments (IA and IB) deal with abnormal loss of salt while the water intake is adequate. The other two experiments (IIA and IIB) deal with water deprivation with no abnormal loss of salt.