American journal of physiology . ? Do the many influences which modify rightauricular pressure also influence the left, to a similar extent, ina similar way? This communication in no sense purposes anextensive study of this many-phased subject, only enough obser-vations bearing upon this problem are attempted to throw lightupon those questions of cardiac behavior which demanded anal-ysis before further progress upon the subject of the pulmonarycirculation or the pathological physiology of hemorrhage couldbe made. Methods. — The right auricular pressure of anaesthetizedanimals was obtained by a
American journal of physiology . ? Do the many influences which modify rightauricular pressure also influence the left, to a similar extent, ina similar way? This communication in no sense purposes anextensive study of this many-phased subject, only enough obser-vations bearing upon this problem are attempted to throw lightupon those questions of cardiac behavior which demanded anal-ysis before further progress upon the subject of the pulmonarycirculation or the pathological physiology of hemorrhage couldbe made. Methods. — The right auricular pressure of anaesthetizedanimals was obtained by a sound as before described. The reg- i8 Carl J. Wiggers istration of left auricular pressure involved opening of thethorax with its subsequent repair and a re-establishment of theoriginal negative pressure. A large canula (6 mm. in diameter,10 cm. long), guarded by a stop cock, was inserted directly mtothe left auricular appendage of the exposed heart to the level ofthe mitral valves, and tied. During the first experiments the. Figure 1. Pressures in auricles (upper record right, middle record left auricle)showing respiratory and cardiac variations. Letter V indicates points where pressureswere measured. stop cock was situated near the auricle and, after repair of thechest, was operated by a handle projecting externally. In laterexperiments it was found that coagulation could still be avoidedwhen the stop cock of the canula was placed entirely withoutthe chest. The right auricular sound and left auricular canulawere connected with membrane manometers of special construc-tion, purposely chosen of such sensitiveness that they respondedto respiratory variations of pressure, but reacted only sHghtlyto the cardiac variations. Their movements in the later experi- i Observations on the ^Effective Pressure in the Auricles 19 ments were photographed on a moving bromide film. Theentire manometer system (including sound and canula) had avibration rate of 18-20 per second which, though l
Size: 1728px × 1446px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookautho, bookcentury1800, bookdecade1890, booksubjectphysiology
