Hello everyone, How are you all? i hope you are doing great and well but i am not happy at all and i am mourning a lot inside. lets come to the core of the post, we have learned the blood bag components and what it contains and its uses. after that we have seen the blood collection and indications and how much blood is collected. If you missed those two you can read the here. Today we are going to learn how this blood which is collected will be divided into different components and basically how Platelet rich plasma is prepared.
Its better if we learn through a scenario

Scenario
Consider a male or female patient came to the hospital with bilateral knee pains from many years and she was advised medications but not reduced much. So the doctor advised the patient PRP(Platelet rich plasma) for treatment. Then the patient was sent to blood bank to donate blood and extract platelet rich plasma from it for treatment. The patient has consulted the transfusion medicine(blood bank) with doctors written advised form and the patient was underwent all the prerequisites and tests before donating blood. The patient was perfect for blood donation. For unilateral knee pain(osteoarthritis) 75 ml of whole blood is taken out while for bilateral knee pain(osteoarthritis) 100ml of whole blood is taken. Then this blood bag is sent for preparation of platelet rich plasma(PRP). We already know that it is a quadruple bag and one bag which contains CPDA or CPD will be having this 100 ml of whole blood. The other bag contains SAGM. The another bag labelled as Fresh frozen plasma or cryoprecipitate and another one transfer bag. So here, The SAGM is transported to small bag and it got emptied.

Seperation of Red blood cells and plasma with platelets

Then the Quadruple blood is kept for 1st centrifugation(soft spin) in the machine and it is kept at 1350 RPM for 10 mins at 22 °C, Red blood cells get settled down and the plasma with platelets will be on the top of it.
Watch the video for crystal clear understanding.

I will show you how platelets looks like don't worry.... then we have to separate the plasma which contains platelets from red blood cells which are at the bottom of the blood bag. So for this one instrument will be there and it is called plasma extraction and we have to keep the blood bag in it and slowly we have to press then it will slowly transfer the plasma and the platelets into the transfer bag.

Then, we have to close the blood bag and should not allow the red blood cells go into the transfer bag. Then the bag which contains the red blood cells and the small bag which contains SAGM should be discarded.

Two bags are discarded

Now we have only two bags- one is the transfer bag which contains plasma with platelets and another one fresh frozen plasma/cryoprecipitate bag.

Preparation of platelet rich plasma

we will get platelet rich plasma. Watch the video of my youtube channel

Then the bag which contains plasma and platelets needs to go centrifugation which is hard spin(2nd centrifugation) at 3474 RPM for 10 mins at 22°C so that the platelets will be settled at the bottom of the bag and the supernatant one is plasma. Now using the same plasma extraction instrument separate the plasma and platelets. The plasma is extracted and leaving a little amount of plasma with the platelets and this is called platelets rich plasma(PRP). We have to weight it should be 20-40 gms or 20-40 ml in weight. Then we have to give this to patient so that it wil be loaded into syringes and given as injections to treat osteoarthritis for the patients. Plz watch the below video for understanding.

Platelet rich plasma with platelets in it

This is how platelet rich plasma is prepared. I hope you understood and next post we will come with random donor platelets.

References

• Kawthalkar SM. Essentials of Clinical Pathology. 2nd edition 2018.
• TRANSFUSION MEDICINE TECHNICAL MANUAL Third Edition 2023

Thanks for reading,
With regards,