Abstract: The invention provides a process and apparatus for externally measuring the arterial blood pressure of the patient by using at least one force sensor intended to be held pressed in the anatomical gutter of the radial artery with a constant force less than that created by the diastolic pressure of the blood flow in the radial artery, by detecting (21, 25, 27, 30) the maxima and the minima of the pressure signals, calculating (29,32,33) the average of the ratios R of these maxima and minima, increasing the application force until the blood flow (diastolic pressure P.sub.D) is disturbed, calculating the systolic pressure P.sub.S =P.sub.D .times.R.sub.m and displaying (17) the values P.sub.S and P.sub.D.

Abstract: An apparatus whose case (12) has advantageously the general shape of a pen, for the external measurement of the heart beat frequency of a patient, comprising: at least one dynamometer (10) intended, during operation, to be held pressed in the anatomical gutter of the radial artery with a substantially constant force less than that created by the systolic pressure of the blood flow in the radial artery; means for detecting the maxima of the flow; computing means for determining the heart beat rate; and means (11) for displaying this rate.