Partial dearterialization of the spleen in thalassemia major

Nine patients with thalassemia major (8 boys, 1 girl; age 3 to 8 years) who had signs of hypersplenism and required more than one blood transfusion per month (1 to 2 weeks) underwent partial dearterialization of the spleen (PDAS) from April through December 1992. All were on a low transfusion regimen (Hb < 10 g%). Hematologic profile, IgM and splenic dimensions (SD) by sonography were determined preoperatively and postoperatively during follow-up periods. Isotopic scan was also performed a few months and 2 to 4 years after operation. The patients did not receive pneumovax or long-term prophylactic antibiotics. The procedure consists of division of the splenic arterial branches, except the one that supplies the superior pole, along with preservation of all the veins.

Seven patients with SD less than 11 cm (6.9 to 10.8 cm; four with less than 9.5 cm) had uneventful recovery. Two others with SD greater than 13 cm (13.2 to 13.5 cm) required total splenectomy a few days after PDAS because of splenic enlargement associated with high fever. One patient was lost to follow-up after 18 months. The remaining six patients underwent follow-up for 4 to 4.5 years. The hematologic profile (Hb, RBC, platelet counts) showed significant improvement during follow-up period. The blood transfusion requirement in all patients was once every 25 to 32 days except one in which transfusion was increased to every 2 to 3 weeks during the fourth postoperative year. The ultimate magnitude of the hematologic response compared with 15 matched splenectomized patients studied retrospectively in a 4-year period was almost the same in the majority after the first postsplenectomy year. There was no significant change in SD by sonography in four patients compared with preoperative state, but a 30% decrease was seen in the other two during the follow-up period. Isotope scan showed a functional residual spleen in all six, with no remarkable difference in size 4 years after operation, except in the one who relapsed. The IgM level did not fall significantly after operation, nor did signs of infection develop in any patient.

PDAS is a safe and effective mode of therapy in thalassemia major, provided the disease is not advanced and SD does not exceed 11 cm in its greatest diameter.