Separating and accurately collecting specific cellular fractions of blood by apheresis remains a challenge despite significant advances in technology.
Visualizing simple physics principles allows one to successfully make adjustments that result in a better product. Understanding the basic principles allows the operator to make decisions based on science rather than just pushing buttons or using charts and shortcuts.
We generally think higher density objects sink deeper. But that is not the case in almost half of the situations in apheresis. We will simple practical everyday examples, with a little math as possible, to explain the counterintuitive phenomena.
The following topics will be covered in addition to glimpse of others related topics:
How cell separation should work and what can go wrong with it?
Error messages: what is actually going on inside the separator
“What if situations”: how changing parameters influence separation.
Why do the same physical principles cause cells to behave differently in different situations? How does centrifugation work? How Inlet flow, Dwell Time and Packing factor/Separation factor etc are adjusted for different protocols?
How does Nonequilibrium-Centrifugation give rise to apparently-paradoxic arrangement of cell layers? What is stokes law? What is elutriation? How is it deployed differently by different machines for various purposes?
Various examples of counterintuitive phenomena will be explained including examples in apheresis chambers and elutriation chambers. A few historic inventions will also be glimpsed.
How to approach and troubleshoot different types of expected and unexpected problems in different types of instruments and procedures? Just two or three basic biophysics principles can explain almost all of the above and help troubleshoot. Lack of their understanding can not only cause collection/depletion of wrong layers but even jeopardize patient/donor’s life. These will be explained in extremely simple way with pictures and real-life examples and a lot more.
Appreciate how the same principles are exploited differently by the various inventions and their historic journey that revolutionized apheresis.
Identify the apparently counterintuitive phenomena in cell separation in apheresis & elutriation by using simple physical principles.
Apply the basic principles in different instruments & procedures, and systematically complete troubleshooting in such situations.
MS, MD, Diplomate of the American Board of Pathology (CP, BBTM),
Assistant Professor, All India Institute of Medical Sciences, Jodhpur