FORT SAM HOUSTON, TEXAS –
The Food and Drug Administration announced June 29 the
approval of cold-stored apheresis platelets for the resuscitation of bleeding
patients. The agreement by the FDA allows storage of apheresis platelets for
three days at refrigerator temperature, which is between 1 to 6 degrees Celsius
or 33.8 to 42.8 degrees Fahrenheit.
The change is welcomed by military researchers at the U.S.
Army Institute of Surgical Research at Fort Sam Houston who see this as a first
step to further development of cold-stored platelets for treatment of combat
wounded warriors on the battlefield.
“This was a very important decision from the FDA,” said Dr.
Heather
Pidcoke, research physiologist and deputy task area manager of the USAISR
Coagulation and Blood Research Program.
According to Pidcoke, research conducted at the USAISR on
platelets collected by apheresis and stored in the cold shows that the
platelets retain blood clotting qualities longer and are less likely to be
contaminated by bacteria than the current standard-of-care room temperature
stored platelets.
“We found that platelets were active and functional in the
cold up to 14 days, whereas we found much diminished aggregation response in
the platelets stored at room temperature after day three,” Pidcoke said.
“We will now be able to conduct research on extending the
FDA-approved storage time of cold-stored apheresis platelets to beyond three
days,” said Lt. Col. (Dr.) Andrew Cap, USAISR Coagulation and Blood Research
Program chief.
“That’s where our research is focusing now,” Pidcoke added.
Before the change by the FDA, bleeding patients could only
be transfused with apheresis platelets stored at room temperature, which
circulate in the body for longer periods of time than cold-stored platelets,
but lose most of their blood clotting function during storage.
According to FDA regulations, platelets can be stored at
room temperature for only five days because of the increased risk of bacterial
growth in room temperature products. This risk forces hospitals to quarantine
platelets for bacterial testing before transfusion.
“That takes two days,” Pidcoke said. “If nothing is growing
on day two, then it can be transported or used on or after day three when the
results are known. In essence, room temperature platelets only have a three day
functional shelf life – like cold-stored platelets.”
Cold storage of apheresis platelets will make them safer and
will allow them to be used immediately without bacterial testing, like red
blood cells. Pidcoke added that there are other benefits to cold storage of
apheresis platelets.
“Cold-stored platelet bags can be added to red blood cell
and plasma bags in a chilled ‘Golden Hour’ blood transport box,” he added.
“This makes it practical to give platelets on the battlefield.”
Another benefit of cold-stored platelets is the need for a
machine to shake the room temperature stored platelets is eliminated, “which
reduces the footprint or equipment needed in a battlefield operating room,”
Pidcoke said.
Platelets are a vital component in blood that combines with
red blood cells and plasma to form clots that stop or minimize blood loss.
Trauma patients with severe bleeding can be transfused with platelets to assist
with coagulation.
“If you don’t have platelets for trauma patients, you are
going to have a hard time saving lives,” Pidcoke said. “The research here at
the USAISR has taken a major step forward in trying to achieve that goal.”