Improvements are described in the method of following temperature changes, and thus alterations in vasomotor tone, in exposed mucous membranes. Invention of an applicator holder, by means of which more sure and stable apposition of the thermopile terminals to the mucous surface may be effected has been the chief advance. Minor improvements have been the use of a saliva ejector and of better calibration technique.
The palatine tonsils, like the palate, pharynx, and skin, react to chilling of the body surface with reflex vasoconstriction and ischemia. On rewarming the subject the tonsils quickly more than recover their former blood supply, actually becoming hyperemic; the skin returns to about its control condition; the pharynx and palate remain somewhat ischemic.
The hypothesis is advanced that one factor in the beneficial hardening effect of cold bathing and outdoor living, with its incident heightened immunity to respiratory infection, may be the training of the vasomotor system in the direction of development in the pharynx of a reaction of hyperemia following chilling, similar to that observed in the tonsils of the present subjects.
With inhalation of amyl nitrite, the skin temperature has always shown a sharp transient rise. The mucous membrane, if relatively ischemic, responds by a rise corresponding to the skin flush. If already hyperemic, local vasodilation in the mucous membrane with amyl nitrite is more than counterbalanced by the lowering of the general blood pressure, and the temperature falls.
The flora of the pharynx and tonsils, studied by the unsatisfactory method described, showed, in several instances, after experimentation changes apparently due to proliferation of one of the microorganisms already present. In one case Streptococcus hæmolyticus, in one Micrococcus catarrhalis, and in a third Bacillus influenzæ was the organism showing a relative increase in numbers. The first two instances were associated with sore throat, the third with slight constitutional symptoms.
The chilling in the experiments in no instance produced albuminuria or glycosuria, although a more dilute urine was apparently excreted during the experiments. A fall in hydrogen ion concentration, referable to the forced respiration, was noted.