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Since the publication of Sir James Mackenzie's 1 book, Heart Disease and Pregnancy, a growing interest has developed in this subject. A large number of such patients are observed annually at the Woman's Clinic of the New York Hospital. The nature of their heart disease and the results of its management in a special cardiac clinic were reported in 1937 by Stander and Kuder. 2 While most of them experienced no cardiac difficulty during pregnancy, the maternal mortality of the group was twice as great as the general maternity mortality of the clinic and accounted for 10 per cent of the obstetric deaths. Since the report by Stander and Kuder, many more cardiac patients have been observed at the Woman's Clinic of the New York Hospital, and considerable information has accumulated concerning them. For the present report, information relating to those patients who developed cardiac failure associated with pregnancy has been analyzed.

The thermal sensitivity of skin to radiation has been studied with a new technique and the temperature changes in the skin surface have been accurately measured. The change in skin response of both whites and negroes to visible, infrared radiation, and sunlight has been measured. Results show that the sensation evoked by the radiations depends upon the optical properties of the skin. White subjects were found to be more sensitive to heat than negroes. The effect of the exposed area upon the sensitivity was observed. The postulate that the magnitude of the sensation depends upon two factors, nerve impulse frequency and central association, was found to fit the present data. A formula for calculating the degree of association is proposed. The results show that the sensitivity to radiation increases as the exposed area is increased up to the point where the stimulus has dropped to 0.0004 gram cal./sec.·cm2. A radiation weaker than this will evoke no sensation regardless of the size of the area exposed. This was taken to be the threshold of the excitation of an end organ. The temperature change in the skin surface with this radiation rate was measured to be a rise in temperature at the rate of 0.0008°C per second; sensation is perceived after 3 seconds of exposure. The relationship of the temperature change of the skin was studied. It was found that neither the change (ΔT) nor rate of change (ΔT/Δt) of skin temperature is adequate to explain the sensory effect. An hypothesis is proposed which attributes the sensation to a differential change in the temperature of the blood vessel net work within 0.1 mm of the skin surface and another at 0.3 mm.

Excerpt Pneumonia is one of the rare complications of pregnancy. Among about 15,000 obstetrical patients in the Lying-In Hospital during the past five and one-half years pneumonia has been seen onl...