Splenic blood flow and intrasplenic platelet kinetics in relation to spleen volume

Abstract

Summary The relationship between the splenic blood flow and the intrasplenic platelet kinetics on the one hand, i.e. the two factors which govern the size of the exchangeable splenic platelet pool, and the spleen size on the other were assessed in 21 patients afflicted with haematologic disorders and variable splenomegaly. The splenic blood flow and intrasplenic platelet kinetics were measured using 111In‐labelled platelets and compartmental analysis of their equilibration between circulating blood and splenic pool; the spleen size was determined by scintigraphy using 99mTc‐labelled stannous colloid. Significant correlations were recorded between the spleen size and the splenic platelet pool size (r= 0.76; P<0.001) and between the spleen size and the splenic blood flow (r= 0.56; P<0.01). Splenic perfusion decreased significantly with increasing spleen size, but there was no relationship between the spleen size and the intrasplenic platelet transit time. However, an association was present between splenic perfusion and intrasplenic platelet transit time (r=—0.44; P<0.05). It is concluded that the splenic blood flow is the major determinant of the size of the exchangeable splenic platelet pool in splenomegalic states, and that the determination of spleen size using 99mTc‐scintigraphy gives a rough estimation of the pool size. Splenic perfusion appears to be one of the factors which determine the intrasplenic platelet transit time.

Predictive factors for platelet increase after partial splenic embolization in liver cirrhosis patients

“…Thrombocytopenia in cirrhotic patients has been reported to be caused by an increased platelet pool in the enlarged spleen. [12][13][14] The increase in platelet count after PSE has been suggested to be caused by a reduction in the platelet pool in the diminished spleen and an improvement in platelet destruction in the spleen through immunological mechanisms. 2,15 Our results suggest that PSE reduced the platelet pool in the spleen, and the increase in platelet count was dependent on the reduction in splenic volume.…”

The spleen and pooling of blood cells

“…In contrast, the factors controlling the intrasplenic platelet transit time are almost unknown. However, the intrasplenic platelet transit time seems to be independent of the spleen size but appears to be inversely related to splenic perfusion (14)(15)(16)18). Platelet size, platelet antibody coating, intrinsic platelet abnormalities and splenic macrophage function are other factors which might influence platelet transit time (19)(20)(21).…”

Evaluation of splenic infarction ratio and platelet increase ratio after partial splenic artery embolization

“…Thrombocytopenia in patients with cirrhosis is reportedly caused by an increased platelet pool in the enlarged spleen. [15][16][17] The increase in the platelet count after PSE has been suggested to be caused by a reduction in the platelet pool in the diminished spleen and enhanced platelet destruction in the spleen through immunological mechanisms. 18,19 In some studies, the increase in the platelet count was positively correlated with the splenic infarction ratio, 18,20 and the splenic infarction ratio was a critical factor for improving thrombocytopenia after PSE.…”