The effects of posture on the velocity of blood flow from arm to tongue

Abstract

A marked divergence of opinion exists as to the effects of posture on the velocity of blood flow and on cardiac output. Thompson Alper, and Thompson, 1 employing brilliant vital red, observed a pronounced increase in both the arm-to-foot and foot-to-arm circulation times in the standing-still posture, as compared to the recumbent position. Further, when they produced moderate venous congestion in a lower extremity by the application of a tourniquet, with the subject in the recumbent position, the appearance of the dye was delayed to approximately the same degree as in the standing-still position. Bock, Dill, and Edwards 2 found that the histamine circulation time (ankle-to-face) in the standing position was 1 1 2 to 4 1 2 times greater than in the recumbent position. Mayerson, Sweeney, and Toth, 3 who studied eleven normal male subjects, observed a marked increase in circulation time when the subject was tilted passively from the horizontal position to an angle of 75° with the horizontal; the testing agent 4 was injected into the foot vein. However, in those instances in which the agent was injected into the antecubital vein, their results were equivocal. Kvale and Allen 5 noted a longer arm-to-foot circulation time 4 in the upright posture than in the recumbent position, but the arm-to-tongue results were variable, i.e., the time was increased in 4 subjects, reduced in three, and unchanged in one. More recently, Main and Baker 6 found no significant difference in arm-to-tongue circulation time (calcium gluconate) between the recumbent and standing positions in eleven subjects. In accord with the observation that there is a reduction in velocity of blood flow in the upright posture, many investigators 7–13 have found that the minute cardiac output is reduced in the upright posture. Conversely, the contention of some workers 14, 15, 16 that posture exerts no influence on cardiac output would tend to support those studies in which blood velocity was found to be unaffected by changes in posture. The present study was undertaken to compare the arm-to-tongue time in two positions, namely, with the body horizontal, and with the legs dependent.