The study of arterial blood pressure in the new-born has been carried out by many investigators. Most of the results have been observed in only a few subjects, as part of a more extensive study in older children. Von Basch,1 a pioneer in this field, worked with an apparatus which now seems crude, namely, a padded button exerting a measured pressure on the radial artery. Systolic pressure was determined by observing pulsations at the wrist. Following him came Neu,2 Trumpp,3 Oppenheimer and Bauchwitz,4 Gundobin,5 Popoff,6 Ssladkoff7 and Seitz and Becker.8
Paul Balard9 made an extensive study of the blood pressure in the new-born and published several articles on the subject. He did this work with a Pachon oscillometer, the common blood pressure apparatus of France. He found that the average systolic pressure of forty new-born infants was 55 mm. of mercury,