Rj. Adams et al., PREVENTION OF A FIRST STROKE BY TRANSFUSIONS IN CHILDREN WITH SICKLE,CELL ANEMIA AND ABNORMAL RESULTS ON TRANSCRANIAL DOPPLER ULTRASONOGRAPHY, The New England journal of medicine, 339(1), 1998, pp. 5-11
Background Blood transfusions prevent recurrent stroke in children wit
h sickle cell anemia, but the value of transfusions in preventing a fi
rst stroke is unknown. We used transcranial Doppler ultrasonography to
identify children with sickle cell anemia who were at high risk for s
troke and then randomly assigned them to receive standard care or tran
sfusions to prevent a first stroke. Methods To enter the study, childr
en with sickle cell anemia and no history of stroke had to have underg
one two transcranial Doppler studies that showed that the time-average
d mean blood-flow velocity in the internal carotid or middle cerebral
artery was 200 cm per second or higher. The patients were randomly ass
igned to receive standard care or transfusions to reduce the hemoglobi
n S concentration to less than 30 percent of the total hemoglobin conc
entration. The incidence of stroke (cerebral infarction or intracrania
l hemorrhage) was compared between the two groups. Results A total of
130 children (mean [+/- SD] age, 8.3 +/- 3.3 years) were enrolled; 63
were randomly assigned to receive transfusions, and 67 to receive stan
dard care. At base line, the transfusion group had a slightly lower me
an hemoglobin concentration (7.2 vs. 7.6 g per deciliter, P = 0.001) a
nd hematocrit (20.4 vs. 21.7 percent, P = 0.002). Ten patients dropped
out of the transfusion group, and two patients crossed over from the
standard-care group to the transfusion group. There were 10 cerebral i
nfarctions and ? intracerebral hematoma in the standard-care group, as
compared with 1 infarction in the transfusion group - a 92 percent di
fference in the risk of stroke (P<0.001). This result led to the early
termination of the trial. Conclusions Transfusion greatly reduces the
risk of a first stroke in children with sickle cell anemia who have a
bnormal results on transcranial Doppler ultrasonography. (N Engl J Med
1998;339:5-11.) (C) 1998. Massachusetts Medical Society.