Blood physiological resources and their role in physiological adaptation of the body to blood loss (based on the experimental data and calculations)
Ivanov, K.P.
Rossiiskii Fiziologicheskii Zhurnal Imeni I.M. Sechenova 86(4): 459-469
2000
ISSN/ISBN: 0869-8139 PMID: 10870223 Document Number: 515354
In white rats, loss of about 66 +/- 3% of the blood volume results in an abrupt drop of the BP and arrest of the lung respiration. Introduction of a plasma substitute in the volume equal to the lost blood resulted in an increase of the BP and restoration of rhythmical respiration in 9 out of 14 experimental rats. Haematocrit after the blood loss and subsequent administration of the substitute was about 15%. Previously obtained data show that the Ht of about 15% decreases the oxygen transport to tissues. However, an increase in the lung ventilation, a shift of the haemoglobin dissociation curve to the right, an increase of oxygen extraction from the blood, and an increase in the minute blood volume by 50-100%, allow a sufficient oxygen transport to the organism tissues to be ensured at the Ht of about 15%. Thus, the reserve of the blood respiration function of the blood remaining after a life-threatening blood loss plays an important physiological role in replenishing the volume of the lost blood with the plasma substitute and in survival of the organism.