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- Publisher
- American Medical Association
- Copyright
- Copyright © 1915 American Medical Association. All Rights Reserved.
- ISSN
- 0730-188X
- DOI
- 10.1001/archinte.1915.00080060051004
- Publisher site
- See Article on Publisher Site
Abstract
Abstract Among the sources of error in human blood pressure measurements an important factor, which has received comparatively little attention, is variation in pressure between individual pulse waves or between groups of them. It is well known that undulations in systolic and diastolic pressure occur commonly in normal persons with each respiration or at somewhat longer intervals ; and among the cases of cardiac arrhythmia, there may be the widest pressure differences even between consecutive pulse waves. The custom of clinicians to accept the average or the highest of several determinations, or simply the first reading made, while tolerably meeting the needs of practice among cases with regular heart action, amounts to the roughest kind of guess-work in cases of marked arrhythmia. Mackenzie1 gave up the attempt to measure blood in cases of auricular fibrillation. It will be shown, however, that notwithstanding the great differences between individual waves References 1. Mackenzie: Heart , 1911, ii, 283. 2. Weber: Arch. f. Anat. u. Physiol. , 1913, Physiol. Abt. 3. Wybauw: Ztschr. f. klin. Med. , 1911, lxxiii, 214. 4. Erlanger and Festerling: Jour. Exper. Med. , 1912, xv, 370.Crossref 5. Erlanger : Johns Hopkins Hosp. Rep. , 1904, xii, 53. 6. Silberberg: Brit. Med. Jour. , (April 6) , 1912. 7. James and Hart: Am. Jour. Med. Sc. , (January) , 1914, p. 63. 8. A slight error in these calculations will be referred to later. 9. Gittings : The Archives Int. Med. , 1910, vi, 196.Crossref 10. Kilgore : A Quantitative Determination of the Personal Factor in Blood Pressure by the Auscultatory Method , The Archives Int. Med. , this issue, p. 893. 11. It is assumed that the relation between palpatory and auscultatory systolic readings is about the same at different pressure levels. This probably is not strictly true, but it is certain that any error from this source is small and well within the limits of accuracy of the method as a whole. 12. The difference between the apex and the radial counts has been referred to as the "pulse deficit."7 "Abortive beats" has seemed to us a better term because its meaning is clear and it directs attention to the heart, in respect to which these beats are important, rather than to the pulse, where they are not so important. Even in the presence of many abortive beats, there may be an ample number of large beats for the needs of the peripheral circulation ; and from this point of view it seems not quite appropriate to speak of the small beats as a deficit. Indeed they might with less impropriety be referred to as a surplus. 13. Professor Joseph Erlanger has verbally called my attention to the possibility of second heart sounds occurring without a preliminary opening of the semilunar valves. It is quite conceivable that the systolic pressure on the side of the ventricle may at times be sufficient partially to relax the tension on the valves without opening them, and that their return to the tense position at the beginning of diastole may produce a sound. Whether or not this actually takes place would of course be difficult to prove; if it does, the sounds thus produced might be expected to be less intense than the second sounds of the effective beats. 14. The fact that systolic readings by palpation are usually somewhat lower than those by auscultation presumably indicates that the auscultatory method is more delicate for determining the pressure of waves which can pass the cuff. And, since in this rough calculation of the pressure of the abortive beats naturally no margin is allowed for failures to demonstrate them, the line representing them should be a continuation of the auscultatory rather than the palpatory systolic line. 15. Wagner's Handwörterbuch, Braunschweig , 1846, iii, Abt. 2, p. 511 16. Sahli (Diagnostic Methods, 1911, p. 174). 17. California State Journal of Medicine , 1914, xii, 92. 18. v. Frey and Krehl: Arch. f. Anat. u. Physiol. , 1890, p. 31. 19. Erlanger and Hooker: Johns Hopkins Hosp. Rep. , 1904, xii, 145.
Journal
Archives of Internal Medicine – American Medical Association
Published: Dec 1, 1915
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