BOSTON Doctors trying to ward off unwanted bleeding in people receiving chemotherapy or bone marrow transplants can do it with half as many platelets as patients usually receive, researchers reported on Wednesday.
But the platelets, which control clotting, must be given before bleeding starts, they reported in the New England Journal of Medicine. The finding might mean it is possible to stretch the supply of sometimes-scarce platelets.
"It lets us better use the platelets we have," Dr. Victor Aquino of the University of Texas Southwestern Medical Center in Dallas, who led the study, said in a telephone interview.
He said an analysis is under way to see if the low-dose regimen saves money.
Platelets are a kind of blood cell that lack a nucleus. They are filtered out of donated blood, leaving red blood cells, plasma and white blood cells.
If cancer patients start bleeding, the usual treatment is to inject a solution containing 300,000 to 600,000 platelets per square millimeter of body area.
Aquino and his colleagues found that if they routinely gave platelets to prevent serious bleeding, the risk of bleeding was the same whether the dose was 110,000, 220,000 or 440,000.
The patients in the low-dose group ended up using 17 percent fewer platelets that people in the medium-dose group and 53 percent fewer than the high dose group.
The only drawback: Patients in the low-dose group tended to need more platelet transfusions.
"I think it all balances out. The quality of life is about the same," Aquino said.
Stretching the supply of platelets, which can only be stored for about five days, is very important for the people who need them, including some with bone marrow cancer, anemia and chemotherapy recipients.
"Sometimes it can very critical," said Aquino. "There can be times where there are very few platelets in the blood bank and that can be very serious if somebody needs them."
(Editing by Maggie Fox; Editing by Cynthia Osterman)