Total Red Cell Mass Research Articles

Changes in the fluid compartments and dry weights of reimplanted dog lungs.

We studied changes in fluid compartments and dry weights of reimplanted lungs of dogs during the first 6 wk after operation. Excision and reimplantation caused a large increase in lung weight. The increase in weight was maximal 3 days after operation, was proportionately greater in the upper middle lobe than in the lower lobe, and was principally due to increased extravascular water. Dry weight and noncirculating red cells (measured by subtracting 51Cr-labeled red cell mass from total red cell mass as measured by hemoglobin extraction) also increased within 3 days after operation. Lung weight and extravascular water decreased progressively after 3 days and were normal in 6 wk. Chromated blood mass remaining within excised, passively drained lobes did not change at any stage postoperatively. Three days after operation, frozen lung sections showed minimal alveolar fluid but large amounts of peribronchial and perivascular edema which was occasionally blood tinged; submucosal edema was present in a few bronchi. Using intraalveolar Evans blue dye, we confirmed that several bronchial lymphatics close within 6 h and refenerate during the first postoperative week. Many of observed functional changes in freshly reimplanted lungs are temporally related to changes in extravascular water.

Physiological changes in blood volume.

Measurement of blood volume is an important clinical tool in establishing a diagnosis as in polycythemia vera, in assessing the true significance of a low blood count in a patient with splenomegaly, and in evaluating a bleeding patient. In theory, blood volume measurements should be of great value in treating acute blood loss, but this is often too time-consuming to be practicable. The main value of blood volume studies so far has been in clinical research where it is essential for correct interpretation of the peripheral blood measurements. Estimates using the hematocrit (packed cell volume) could be misleading since this measurement does not take into account total blood volume and changes in the plasma volume. A variety of isotopes that tag the red blood cell have been used to measure total blood volume and red cell mass. Most commonly used at present is autologous 51-Cr labeled red cells, thus eliminating the risk of hepatitis in transfusion to the subjects. Radio labeled albumin and other plasma proteins were used to measure plasma volume. A large molecular protein is ideal to eliminate overestimation from extravascular diffusion of labeled material for accurate determination of plasma volume. Physiologic changes in the newborn, in pregnant women, during exercise, bed rest, and altitude in the nonpathologic state are discussed. Studies in the normal subject's adaptation in different physiologic conditions have revealed a variety of factors that regulate blood volume.

The haematological response to androgens in sickle cell anaemia.

To 11 patients with sickle cell anaemia pharmacological doses of androgens were given for periods varying between 3 and 16 weeks. To 3 of the patients two courses of treatment were given. During the treatment 10 of the patients showed an increase of the total red cell mass varying between 25 and 125% of the control value. One patient did not respond. The treatment had no discernible effect on the sickling tendency of the erythrocytes at different levels of oxygen tension and there was no consistent alteration of the red cell survival measured with radioactive chromium. Weight gain was seen in all patients and hirsutism was seen in most of the females. In spite of the marked increase in red cell mass there was no certain increase in the frequency of crisis among the female patients. Priapism occurred in all of the adult males responding to the therapy. The number of patients studied is, however, small and the observation time too short to allow any firm conclusion on the effect of androgen treatment on the frequency of vaso‐occlusive crisis.

Dilution anaemia.

Mice of the strain BALB/c develop a dilution anaemia when transplanted with the plasmocytoma PC 5. The total red cell mass remains unchanged during growth of the tumour whereas the haematocrit comes steadily downwards to 2/3 of the normal value. In spite of the apparent “anaemia”, the mice do not invoke compensatory increases in erythropoiesis as demonstrated by lack of reticulocytosis and lack of erythropoietin production in increased amounts. The animals have retained the capacity to respond to a hypobaric hypoxic stimulus, and it is, therefore, tentatively assumed that the oxygen transport is not decreased in case of dilution anaemia and that the tissue oxygen tension will remain normal.

Hematologic studies of severe undernutrition of infancy. I. The anemia of prolonged caloric deprivation in the pig.

Hematologic studies of severe undernutrition of infancy. I. The anemia of prolonged caloric deprivation in the pig.

Physiologic and pathophysiologic effects of anemia.

TWO 24-year-old women of similar height and weight were hospitalized on the same day; each was subsequently shown to have had, at the time of admission, a total red-cell mass that was 70 per cent of normal. The first patient sought medical attention because of pallor, progressive fatigability of several months' duration and some intolerance to cold. She was Cooperative and in no apparent distress. Vital signs were within normal limits (the pulse rate was 58). Physical examination revealed nothing significant except slight pallor and a cool, dry skin. The hemoglobin was 9.8 gm per 100 ml, the hematocrit 31 . . .

Primary defective iron reutilization: Response to testosterone therapy

Ferrokinetic data in five patients with primary defective iron reutilization before and following testosterone therapy are presented. The anemia in these patients is characterized by hypoferremia, increased iron stores and poor response to iron therapy. Iron utilization as measured by the intravenous injection of Fe 59 citrate is normal, whereas iron reutilization as measured by the intravenous injection of Fe 55-tagged hemoglobin solution is poor. Iron absorption also is poor. Testosterone therapy increased the total hemoglobin mass and total red cell mass in all patients and improved the reutilization of iron, but not the intestinal absorption of the metal.

BLOOD-VOLUME CHANGES IN SEVERE ANÆMIA IN PREGNANCY

THE volumes of red cells and plasma were directly estimated by means of the chromium-labelling technique and Evans-blue dyedilution method respectively, in 78 anæmic and 20 healthy pregnant Nigerian women. In severe anæmia in pregnancy, the P.C.V. and hæmoglobin concentration of the peripheral venous blood give a very good indication of the total red-cell mass before the anæmia is treated; plasma-volume is significantly increased and compensates for the red-cell deficiency. In the presence of multiple pregnancies, gross splenomegaly, and anæmic cardiac failure, larger plasma-volume expansion is found. Total blood-volume is reduced in 25% of the patients in whom the hæmoglobin concentration is less than 4·4 g. per 100 ml., the P.C.V. of the peripheral venous blood is less than 14%, and the total red-cell mass is less than 10 ml. per kg. body-weight. The hæmatocrit ratio is not constant in severe anaemia in pregnancy when the P.C.V. is less than 25%. The total blood-volume can therefore be reliably estimated only by simultaneous measurements of red-cell and plasma-volumes.

THE EVALUATION OF BLOOD VOLUME AND TOTAL RED CELL MASS AS PREDICTORS OF GROSS BODY COMPOSITION IN THE PIG

In a study of growth and development patterns in the pig, data were obtained on body weight, total body protein, blood volume, and red cell mass for a total of 88 pigs, ranging in live weight from 9 to 103 kg. The relationships of total body protein to the other variables were analyzed by multiple regression techniques on both an overall and stratified basis. Over the entire weight range, body weight itself explained 98% of the variability in total protein. When the analysis was restricted to pigs in the weight range of 81–103 kg the contribution of body weight in predicting total protein decreased considerably (50%), with concomitant increase in predictive value of blood volume (8%). It was concluded that blood volume and similar physiological measurements could be of major importance in predicting body composition in market weight pigs.

Erythrokinetics in the horse

Erythrokinetics in 34 adult horses of three different breeds was studied by means of Fe59 tracing technique. The differences observed between the mean erythrokinetic values of the Thoroughbred English race horses and the draft horses were statistically significant. The Thoroughbred showed a greater erythropoietic activity. The erythropoietic activity parallels the total red cell mass of the three breeds, being highest in the Thoroughbred, intermediate in the saddle horse, and lowest in the draft horse.

POLYCYTHEMIA IN RATS FOLLOWING RESTRICTED FOOD INTAKE.

Rats were divided into two groups such that mean weight and hemoglobin and hematocrit levels were not significantly different. One group (controls) was then fed a normal chow ad libitum. The other group was fed 6 g daily (30% of normal intake) for 2 weeks. The hemoglobin levels of rats fed the restricted diet rose 1.4–3.5 g/100 ml and hematocrit level rose 2–6%. At the end of 2 weeks total red cell mass (Cr51) was 5.5–6.0 ml in the underfed groups compared with 6.8 ml in the control group. Body weight fell proportionally more than did red cell mass, elevating the calculated red cell mass per unit body weight. Serum osmolality and K+ were not significantly different from control values, and there was a slightly higher serum Na+ and Cl– in the restricted diet group. It is concluded that restriction of food intake produced a relative polycythemia. At the end of 2 weeks of restriction an isosmotic reduction in plasma volume was present.

Primary erythrocytosis of childhood.

Erythrocytosis (an increase in the total red cell mass)* in childhood is usually secondary to cyanotic congenital heart disease. Occasionally it occurs with pulmonary disease, methemoglobinemia, brain tumors, Cushing's disease, or renal adenoma. When there is an accompanying increase of white blood cells and platelets, the condition is termed polycythemia vera; this is extremely rare in children. Occasionally the condition may be familial with no elevation of white blood cell or platelet count and with no underlying cause or associated condition discernable. It is the purpose of this paper to present a case of primary erythrocytosis in a 6-year-old child whom we have been able to investigate. Report of Case The patient, a 6-year-old boy, was first seen in the Congenital Heart Disease Clinic of the University of Colorado Medical Center on Jan. 22, 1957. He had been referred because of cyanosis and decreasing tolerance for exercise. Pregnancy and delivery

Fall in haematocrit in sheep after treatment with chlorpromazine and dihydroergotamine.

IT was recently shown1 that the jugular haematocrit of sheep often fell considerably (by as much as 24 per cent of the initial value, mean = 12 per cent) when the animals were isolated from alarming environmental stimuli, or were subjected to gentle restraint (‘holding’) and soothing for 15–30 min., and that it fell regularly and to an even greater extent (up to 39 per cent of the initial value, mean = 30 per cent) during anaesthesia by pentobarbitonum. Evidence was obtained that these phenomena are a consequence of splenic relaxation, passive filling of the spleen, and segregation therein of an increased fraction of the total red cell mass in a state of dynamic equilibrium with the circulating blood. The remarkable fall in haelig;matocrit after ‘holding’, which we view as emotional or psychological tranquillization leading to diminution of the sympathoadrenal flux from the cerebral cortex, suggested that this might also occur as a result of pharmacological tranquillization by means of ataractic agents.

Red blood cell distribution in the hypothermic ground squirrel.

The quantity and distribution of the circulating red blood cell mass were studied in the ground squirrel during immersion hypothermia of 2°–4°C esophageal temperature. Mixing of isotopically tagged erythrocytes within the total red cell mass, as determined by comparison with euthermic values, was essentially complete within 10 minutes, so that little, if any, sequestration of blood occurred. The hematocrit ratio of blood within the heart lumina was maintained throughout this cold stress. Complete mixing of Cr51-tagged red blood cells took place within 1 hour in the erythrocytes of the kidney, cardiac muscle, diaphragm and leg muscles. The liver of the cold animal picked up radioactivity, perhaps due to damage of erythrocytes in the labeling process. Splenic contraction within 2 hours of acute hypothermia was indicated by a sharp decrease in its circulating red blood cell mass and by visual observation. The total erythrocyte mass in the cheek pouch of the hypothermic ground squirrel required about 3 hours to equilibrate with labeled cells, so that a small region of very slowly flowing blood did exist in this tissue. Maintenance of red blood cell flow to tissues indicated that some vasomotor control was intact during this acute cold stress. Submitted on January 27, 1959