CENTRAL VASOMOTOR IRRITABILITY

Abstract

In a previous paper1there was described a characteristic feature of essential (not nephritic) hypertension, namely, an increased sensitivity of the vasomotor centers to changes in alveolar carbon dioxide tension: abnormally high rises of blood pressure during the inhalation of carbon dioxide and an abnormal fall of blood pressure during the increased exhalation of carbon dioxide (hyperventilation; Tirala2and Rappaport3). There is a striking parallelism between the figures of alveolar carbon dioxide and of blood pressure during hyperventilation in hypertonic patients, while a fall of carbon dioxide to the same extent does not change the blood pressure of hyperventilating normal persons in any definite way (Collin, Densham and Wells,4Schneider5). From this characteristically different behavior of normal and hypertonic persons the conclusion has been drawn that a pathologic hypersensitivity of the vasomotor centers (not only to abnormally high amounts of carbon dioxide but even to the normal carbon dioxide content