Fresh blood vital in treatment of some Dengue Fever cases

Patients needing blood donations for management of Dengue Fever may need the platelet component of blood which can only be stored for five days at most.

Sir James Mitchell

Therefore, stored blood packs would not be useful for such purposes and new donors would become imperative.

The problem of Dengue Fever is ongoing, and the Ministry of Health authorities continue to advise persons to eliminate breeding sites for mosquitos that could possibly be carrying the viral disease. One of the latest victims to fall sick with Dengue Fever is former Prime Minister Sir James Mitchell, who is hospitalised with Dengue Hemorrhagic Fever. Calls for blood donations for him were widely shared across social media earlier this week.

It is said that Dengue may knock off a person’s platelets so it drives the patient into a condition that is called Thrombocytopenia and this requires them to need a platelet transfusion. Platelets or thrombocytes, are small, colourless cell fragments in the blood that form clots and stop or prevent bleeding.

SEARCHLIGHT reached out to Chief Laboratory Technologist, Elliott Samuel to find out the considerations for the lab in the extraction of platelets.

“…the current paradigm to transfusion is that we don’t just give people blood, we give people what is required, so it’s really called component therapy and at the hospital we have the capacity to break out that blood into all of its components,” Samuel said, “so we can separate off the red cells, we separate off the white cells, we can separate off the platelets, we can separate out the plasma.”

In the case of thrombocytopenia caused by Dengue and the need for a platelet transfusion, he noted, “when you’re giving the transfusion, there’s consideration for pooling the platelets because enough platelets is not in one unit of blood to provide sufficient amount for transfusion.”

“…So we have to actually get a lot of persons to come in to get the volume of platelets up that is going to be beneficial to the recipient.”

Each pint of blood given by a donor would be 450ml of blood, from which at least 40ml of platelets are extracted.

“You will need at least five or six of those to facilitate a single platelet transfusion,” Samuel clarified.

“The thing with platelets is that it’s temperature sensitive. So blood that we have stored on the bank, the platelets in that is destroyed, so while we can give that blood to persons for other reasons, for example if somebody is falling off in terms of haemoglobin, if they need other components we can harvest those components and we can give that blood, but we can’t use it as platelet replacement therapy,” he explained.

“When we are considering transfusion for platelets, the blood has to be collected fresh, the platelets have to be prepared before the blood even goes to storage and it has to be kept separately and that is why whenever you have somebody in great demand for platelets, it really creates a rush to get people to come in on the spot to give that transfusion because we can’t use blood that is on the bank.”

Normally the bank operates on a replacement system, giving blood to the patient in need immediately then asking family/friends/volunteers to replace the blood used.

Platelets can be stored, but the life of it is not long, and it can only be kept for five days.

“After five days the viability is gone so even though we try to prepare platelets and to keep them for emergency use, if nobody is in need of platelets then we just have to dump if it’s after five days,” the Chief explained.

“…Whenever you find people who are in need of platelets it really increases this rush to bring, first of all our volunteer donor pool in, and if we have to exhaust that, then we have to go to the public for persons to come in to make that donation so we can prepare the platelets fresh and have it there viable so we can pass it on to the recipient,” he noted.