Early this afternoon, at Starship and Middlemore Hospitals, a stricken 9 month old baby and a lady diagnosed with cancer were wheeled into theatre for critical surgery.

While I don’t know the details, or the outcome of the surgery, I hope it went well, and they are now on the road to recovery.

Their surgery was in part possible because this morning I donated platelets and my blood type was a match.

Platelets are a blood component required for blood clotting. They play a vital role in surgery on patients with low platelet counts, (such as cancer patients undergoing chemotherapy), or in complex procedures, such as cardiopulmonary bypasses where there will be excessive bleeding that cannot be treated with just whole blood donations alone.

Unlike whole blood (donations), which can be kept in a blood bank for up to 30 days, platelets last at most 5 days. Consequently there is a chronic shortage, and life-saving surgery is reliant on platelet donors coming in at the appointed time. (This is complicated even further if it happens to be an Inter Island donation – although usually patients are transported to Starship or Middlemore)

While platelets can be extracted from whole blood donations, a sufficient yield typically requires processing approximately 12 matching whole blood donations. This increases risk of infections, and the amount of antibodies, and is not ideal for patients with an already beaten immune system.

The best source of platelets is from one donor and is obtained through a process known as apheresis, or plateletpheresis.

Plateletpheresis involves being strapped to a complicated machine resembling a sewing machine with a built-in centrifuge.

As Snug as a Bug, enjoying my cuppa. In just a few hours those platelets would be used in a life-saving transfusion on two very different patients.




The machine draws around 450mls of blood, mixes in some anti-coagulant, and then spins it around in the centrifuge filtering out the plasma and platelets. Once the platelets and plasma have been separated the machine returns the red blood cells back to the donor. This process then repeats 7 – 10 times and takes approximately 90 minutes. The final yield is approximately 350 – 400g of platelets, and a lesser amount of plasma that is incidentally extracted as well.

Because a healthy human body can regenerate the lost platelets within 3 days, it is possible to donate every two weeks.

So if you can spare yourself a couple of hours once or twice a month, and are some kind of O or A, ask one of the lovely phlebotomists at the Auckland Blood Donor Centre about it next time you go in to donate blood.

The procedure is painless (seriously), and the super-friendly staff will ensure you are well looked after, supplying you with cookies, tea, and drinks during the process. It’s also a great opportunity to finally finish reading that book you never seem to get around to.

And if you can’t spare the 90 minutes once a month, another option is to just donate plasma (plasmapheresis). Plasmapheresis is a similar procedure, but doesn’t require the centrifuge, thus usually only takes around 40 minutes – little more than a standard whole blood donation.

For the amount of effort involved apheresis is probably one of the most altruistic contributions you can make.

Plus, if you’re a bloke, being able to say you regularly save babies has to be a sure way of picking up women.

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