REVIEWS
AND
ABSTRACTS
581
if like pressures and temperatures are employed and only if the fluids of the tissue spaces are normal in their initial quantities, or, if increased, equal in their initial amounts in the cases compared. The measured rate remains constant within narrow limits from day to day in any given subject leading a sedentary life. Considerable variation is found when different subjects, all leading sedentary lives are compared. Short strenuous running exercises and long continued walking change the transudation rate, and the pre-exercise rate is not restored until about twenty-f our hours later. Palpable edema occurs when the amount of collected tissue fluid increases the limb volume 8 per cent. Harris, K@nn&h E. and Marvin, K. M.: A No&e) on the Tempera,ture of Venous Blood and Its Use in Estimating Rate of Blood Flolw to the Hand. Heart, 1927, xiv, 49. The authors have devised a method for measuring the temperature of the venous blood in situ by means, of a thermoelectric junction made from a hypodermic needle. This is so arranged that the needle may be inserted directly into a superficial vein on the dorsum of the hand. They have studied the effect of immersing the hand in a water-bath, the tempera&e .of which lies between 36” and 32” C. The temperature of the venous blood, when the hand is at rest, the room temperature being between 20.8” aad 24.4” C., assumes a level between 34.3” and 35.8” C. Using a water-bath between 26” and 32” C., the average difference between the temperatures of the bath and venous blood in the hand is 1.84” C. after fifteen minutes and 1.31” C. after thirty minutes immersion.
Reid, Willkm D.: Paired Auricular Extrasys%oles Sirnula~ting Interpolated Extrasystdes of Supra8ventricular Origin. Arch. Int. Med., 1927, xxxix,
596.
In an electrocardiogram obtained recently from a patient sixty-four years of age, diagnosed as auricular fibrillation, there appear extrasystoles of an unusual type. In an attempt to analyze the nature of these extrasystoles, the author points out the difficulty in differentiating between a true interpolation and pairing of auricular extrasystoles, E. C:cpwles and Martin, Louis E.: The Actioa thetic upon the Excitatory Process in the Mamma&n
Andrus,
Exper.
o’f the SympaHeart. Jour
Med., 1927, xiv, 101’7.
The present study was undertaken in an attempt to exammine certain phases of the action of the sympathetic nerves on the heart of cats and dogs. The authors studied the effect of sympathetic stimuli on intra.-
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THE
AMERICAN
HEART
JOURNAL
They also auricular conduction by injections of adrenalin iolution. studied the paralyzing effect of ergotomine on the sympathetic endings. When the action of the parasympathetic nerves has been excluded by means of atropine, it is possible to demonstrate that the excitatory process in the heart ‘is affected, to a considerable degree, by the control of the sympathetic nerves. From all phases of excitation and conduction in the mammalian heart with the exception of intraauricular conduction, the &ion of the vagus and sympathetic are opposed. IIere the vagus is without effect unless the rate of transmission is abnormally slow. Stimulation of the sympathetic nerves, on the other hand, invariably causes a conspicuous rise in the transmission rate. It is, thkrefore, apparent, upon closer analysis, that the effects of the vagus and sympa,thetic nerves upon intraauricular conduction are in no sensesynergistic. Under normal conditions there exists a delicate balance of such a nature that stimulation of one system involves inhibition of the other. It is, however, significant that following paralysis of both sympathetic and parasympathetic nerves, the normal rhythm is maintained spontaneously at a more or less constant rate.
Merrmaan I.., and We’iss, Soma: Studies on the Velocity of Blood Flow: II. The Ve~locity elf Blood FIow in Nom@ Resting Individuals, and 8 Critique of the IVIethod Used. ,Jour. Clin. .Inves.,
Blumgart,
1927, iv, 15. The chief precautions observed in estimating the velocity of blood flow by the radium active deposit method are described. Direct and indirect evidence is presented that the ionktion effect is due to the radiation which emerges from the arterial blood of the arm. Considerable variations of the dose of the active deposit of radium do not influence the results obtained. Repeated measurements in eleven individuals with regular rhythm agreed within an average of two seconds. The variation never was more than three seconds except in two individuals in whom it amounted to four scconils and five seconds, respectively. Measurements can be repeated as early as three hours. The circulation times of fifty-three normal restin g male individuals are presented. The arm to arm circulation time in normal rest&g individuals may vary between fourteen and twenty-four seconds when the active deposit is injected into the cubital vein of one arm and the onset of radiation from the arterial vesselsof the other arm is detected. The arm to arm circulation time does not become more prolonged with advancing age as measured by the method described. There: is no critica, age beyond which the velocity of blood flow tends to diminish. The average arm to arm cireulation time in fifty-three normal persons between the ages of fifteen and seventy-five was eighteen seconds. The average arm to arm circultition time when rednccd to squn.rc meter of body surface was ten seconds in individuals bctwecn the ngcs of ElLtecn and twenty-nine, and eleven sec-