Red Cell Pool Research Articles

Effect of splenectomy on anemia in patients on regular dialysis treatment.

Splenectomy was performed in 7 patients on regular hemodialysis treatment who had disabling anemia. All patients had a short 51Cr red cell survival time and an increased splenic uptake of red cells verified by external counting and computer-aided scintigraphy. The need for blood-transfusions was eliminated in all except one. In all patients the hemoglobin concentration rose after splenectomy. This was probably an effect of a reduced plasma volume and the removal of a large pool of non-circulating red cells. No consistent changes in the red blood cell survival time or the red cell volume were observed. The white cell and the platelet counts in the blood rose to twice the preoperative value. No adverse effect of the splenectomy was observed.

Haematological changes in active chronic hepatitis with reference to the role of the spleen.

The haematological role of the spleen has been investigated in a series of 22 patients with active chronic hepatitis. Severe pancytopenia occurred in one patient after three years of steroid therapy and this episode was associated with an increase in spleen size and a high splenic index of red cell destruction. Although the spleen was usually enlarged in the remainder of treated and untreated patients no others showed increased splenic haemolysis. The red cell survival was slightly reduced in most patients but splenic pooling of red cells and expansion of the plasma volume did not significantly reduce the haematocrit level. No consistent haematological differences were detected between the untreated and the treated patients.

Red cell, plasma and whole blood volumes in organs of normal and hypersplenic rats.

Volumes of red cells and plasma were measured in organs of normal and “hypersplenic” rats by means of59Fe-labelled erythrocytes and131I-labelled human serum albumin respectively. The “hypersplenism” was induced by a long-term intraperitoneal application of methylcellulose. Blood volumes in the spleen and myocard of normal rats formed roughly one-fifth, in the kidneys, lungs and liver about one-fourth to one-third of the organ weight. The absolute volume of red cells, plasma and blood in the spleen of “hypersplenic” rats was higher than in controls. When expressing these values as a per cent from the total blood volumes, 7.5times more red cells and 5times more plasma were found in “hypersplenic” rats compared with normal animals. These results speak for an existing splenic pool of red cells. The changes of blood volumes in other organs (liver, kidneys, lungs and myocard) were far more discrete.

Changes in spleen cellularity and erythrocyte accumulation following Rauscher virus infection in the mouse.

The nature of the relationship of the spleen enlargement effected by Rauscher virus infection of SJL/J mice has been investigated with reference to cell proliferation in the spleen and to splenic red blood cell pooling and anaemia. The gross splenic nucleated cell content was found to increase linearly with spleen weight. The ratio of total spleen cells to nucleated spleen cells was identical at a value of 1.75 to 1 for both normal and virus‐infected mice even though in the latter some spleen sizes were as high as 30 times normal. On a per milligram basis, the average splenic accumulation of 59Fe‐labelled normal red blood cells by normal mice was approximately twice as great as by 18‐day leukaemic mice, even though the leukaemic spleens contained a greater fraction of the injected label.Anaemia was seen to develop shortly after injection of the virus, reducing the haematocrit to values of less than 40 by two weeks. Compensatory increase in reticulocyte number did not occur until after the major fall in venous haematocrit had already been achieved. Peripheral white blood cell counts increased with time after virus injection and these correlated positively with spleen size, the relation being logarithmic.

The influence of spleen size on the distribution of red cells and plasma.

The red cell mass, splenic red cell pool, and plasma volume have been measured in a series of 64 patients with splenomegaly due to haematological disorders. In 45 patients the total blood volume was increased, this being due to expansion of the plasma volume which was closely correlated with spleen size. There was no significant relationship between the red cell mass and spleen size but the splenic red cell pool increased with increasing spleen size. In 12 patients serial estimations were made whilst changes in spleen size occurred as a result of therapy or progression of the disease. The red cell mass did not alter but the splenic red cell pool showed a significant change from 8.9 +/- 6.1% of the red cell mass at minimum spleen size to 17.5 +/- 10.5% at maximum spleen size. There was progressive expansion of the plasma volume from 42.9 +/- 5.0 ml/kg at minimum spleen size to 57.4 +/- 15.3 ml/kg at maximum spleen size.

Splenectomy in Anaemia

Splenectomy has been carried out for anaemia on 104 patients suffering from haematological disease. The mortality was 3 per cent. The indications for this operation are considered and the predictive value of estimations of splenic red cell destruction, splenic red cell pooling, and the plasma volume have been examined. None of these tests gives an unequivocal prediction but are of value in reaching a decision. Removal of a splenic site of red cell destruction and a reduction in plasma volume appear to be associated with post-operative haematological improvement. However, the changes in plasma volume seen after splenectomy are usually only temporary and revert slowly over several years.

Plasma volume and splenomegaly in polycythaemia vera.

SummaryBlood volume studies in 23 patients with polycythaemia vera showed the mean plasma volume to be normal when compared with control subjects, and variation in plasma volume for the group as a whole was no greater than in normal subjects. However, the polycythaemic subjects proved to be heterogeneous with respect to plasma volume: in one subgroup, showing splenomegaly with demonstrable intrasplenic red cell pooling, there was a moderate increase in mean plasma volume. In addition, the effect of intrasplenic red cell pooling on the whole body haematocrit/venous haematocrit ratio was found to differ in this condition from the effect in non‐polycythaemic subjects: the splenic pool failed to concentrate red cells significantly above the levels present in the extrasplenic circulation, and did not result in a rise in the Hb/Hv ratio.

Tropical splenomegaly syndrome in New Guinea. II. Long term results of splenectomy.

Between 1965 and 1967 splenectomy was performed on 21 Watuts and 5 other New Guineans to relieve persistent incapacitating symptoms of tropical splenomegaly syndrome. There were 3 operative deaths. Post-operatively abolition of the splenic red cell pool, correction of the shortened red cell survival time and reduction in plasma volume occurred, leading to a mean rise in haemoglobin concentration of 3·7 g./100 ml. Neutropenia and thrombocytopenia were also corrected. There was a rapid post-operative fall in serum IgG and IgM concentrations, and a prolonged reduction in intravascular pools of both immunoglobulin fractions. The 18 Watuts discharged from hospital and followed for from 41 to 74 months have had significant symptomatic relief, although 7 have died following short illnesses; this mortality rate (36%) is substantially less than that of a comparable group of Watuts not subjected to splenectomy.

Tropical splenomegaly syndrome in New Guinea. I. Natural history.

Abstract The course of the tropical splenomegaly syndrome has been observed for periods of up to 6 1 2 years in 75 adults living in the Upper Watut Valley of New Guinea. During this time there were 27 deaths, 2 from septicaemia and another 8 from similar fulminating febrile illnesses. The mortality rate in those with Grade V splenomegaly was 57%, almost 3 times that of the remainder. Serial hospital assessment of 26 subjects demonstrated progression of the disease, characterized by further enlargement of the spleen and a fall in haemoglobin concentration in 9; increases in splenic red cell pool, in plasma volume and in serum IgM concentration were sometimes, but not invariably, associated. In none of the total group of 75 subjects was a decrease in spleen size observed. Thus the natural history of the tropical splenomegaly syndrome is that of a progressive disease with a high mortality in the fully developed case. Periodic fluctuations in the clinical severity of the disorder are frequently seen and are largely related to the occurrence of episodes of acute haemolysis; however, spontaneous remission has not been observed.

Regional variations in the proportion of red cells in the blood in man.

Summary:Surface counting techniques following the intravenous injection of 51Cr labelled red cells and 131I labelled human serum albumin have been used to investigate the regional haematocrit in normal subjects, subjects with splenic enlargement and after splenectomy. Regional variations in the proportions of red cells and plasma were demonstrated, the red‐cell concentration being highest at the precordium and lowest in the hepatic region. Intermediate values were obtained for the lumbar and splenic regions in normal subjects.The enlarged spleen has a definite but variable tendency to be associated with high local haematocrit values when compared with the venous haematocrit. Raised whole‐body to venous haematocrit ratios result from the pool of red cells in the spleen which shows delayed mixing with the cells of the extrasplenic circulation. The raised whole‐body to venous haematocrit ratio associated with splenomegaly is more dependent on the concentration of the pooled cells relative to the venous haematocrit than on the volume of pooled cells and spleen size.The significance of variations in regional to venous haematocrit and whole‐body to venous haematocrit ratios is discussed.

RED-CELL POOLING IN ENLARGED SPLEENS.

RED-CELL POOLING IN ENLARGED SPLEENS.

ROUTINE COMPATIBILITY TESTING: STANDARDS OF THE AABB AS APPLIED TO COMPATIBILITY TESTS.

The results of a blood group antibody survey carried out with the cooperation of 20 blood grouping laboratories are given. These results are used in a discussion of the antiglobulin phase of compatibility tests as they are outlined in the AABB Standards for a Blood Transfusion Service. A total of 37,961 irregular antibodies were reported. 37,811 or 99.6% of these antibodies could be detected by routine screening procedures using a pool of red cells from two or three selected donors, provided the pool contained the red cell antigens present in more than 2.5% of the Caucasian population. Only 145 or 0.4% of the reported antibodies would not be detected by such a routine screening test due to the fact that they react with red cell antigens present in 0.5% or less of the Caucasian population. Based on the antibody survey and a report of the antibodies responsible for 222 hemolytic transfusion reactions reported from 18 of the laboratories, a case is made for the use of routine antibody screening before all crossmatching procedures. If a carefully controlled screening test is negative it seems unnecessary to carry out the antiglobulin phase of the crossmatch. The serum or saline and high protein phases are still obligatory. If the screening test is positive, the antibody can be identified, making possible selection of suitable donor bloods before crossmatching is undertaken.