A Study of the Effects of Hemorrhage, Trauma, Histamine and Spinal Anesthesia on the Composition of the Blood When No Fluids Are Injected and When Fluids Are Introduced Intravenously

Abstract

In previous studies (1, 2) the composition of the blood has been determined before, during and after the injection of various fluids intravenously under normal and abnormal conditions. The abnormal conditions consisted of some experiments in which a decline in blood pressure was, produced by trauma to the intestines and others in which probably due either to the anesthetic or to the fluid that was injected intravenously there was an early marked decline in the pressure. The results of these experiments led us to further studies on the composition of the blood of animals in which a decline in pressure was produced by other methods. These methods consisted of (1) graded hemorrhages, (2) trauma to an extremity, (3) the subcutaneous injection of histamine and (4) spinal anesthesia. These procedures were chosen because a large number of the instances of low blood pressures in patients are due to similar causes. Experiments were performed both with and without the introduction of fluids intravenously. The fluids that were chosen for study were normal salt solution and Evans' gum acacia-glucose-saline solution. These two fluids together with others were employed in the previous studies and in the present experiments they were used as examples of solutions of crystalloids and of colloids. METHODS AND RESULTSThe experimental animals in all instances were dogs. They were anesthetized by morphine except in the experiments in which an extremity was traumatized. In the latter experiments, sodium barbital, 0.3 gram per kilogram of body weight, was administered intravenously. The animals gave no evidence of pain and were killed at the completion of the experiments. A cannula that was connected to a mercury manometer was placed in the carotid artery for the blood pressure determinations. Samples of blood for the various analyses were obtained from the femoral vein. The blood that was removed was replaced by an equal volume. 291

Intravenous Injections

“…The total protein, the albumin and the globulin were determined by the same methods used in the experiments described in a previous paper (1). The absolute amounts of the protein constituents were obtained by multiplying the percentage of each by the plasma volume.…”

“…In a previous study (1) in which the composition of the blood was determined in experiments in which fluid was injected continuously while the intestines were being traumatized, it was found that there was a great decrease in the protein content as well as in the volume of the blood plasma. The object of the experiments reported in this paper is to determine the effects of the intravenous injection of fluids on the composition of the blood of normal dogs.…”

The Treatment of Shock Due to Salt Depletion; Comparison of the Hemodynamic Effects of Isotonic Saline, of Hypertonic Saline, and of Isotonic Glucose Solutions 12

“…On the other hand, our experiments clearly prove that conclusions concerning the deleterious effect of intravenous saline derived from many experiments on traumatic shock cannot be applied to all other forms of shock (9,10,6). At the 4 or 5 hour point of a shock state produced by salt depletion, intravenous administration of saline is a therapeutically valid procedure.…”

“…At first sight, they may seem inconsistent with findings of other workers who have found that the intravenous administration of saline solutions to animals early in traumatic shock as the blood pressure is falling usually results in a further loss of circulating plasma protein, rather than its restoration (9,10,6 The unsatisfactory results of glucose therapy are obvious. In contrast to saline therapy, extracellular volume and plasma volume reexpanded to a lesser degree, protein was not restored to the circulating plasma, and the hemodynamic status of the animal was not distinctly improved.…”