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>prick-sized droplet may simply not be a large enough sample size for the tests they want to run This was always the main criticism of Theranos. Finger-stick b
by onewaystreet 11y ago
>prick-sized droplet may simply not be a large enough sample size for the tests they want to run
This was always the main criticism of Theranos. Finger-stick blood tests have never been considered reliable for clinical diagnostic tests because you don't get enough blood and the blood you do get can be contaminated.
- brandon272 11y agoHow does the blood become contaminated?
- paulcole 11y agoStuff on your fingertips.
- CamperBob2 11y agoFor one thing, it's almost impossible to get your skin perfectly clean. Any test that uses a single drop of blood will be very sensitive to even the slightest amount of soil or contamination on the fingertip where the drop is extracted.
- brandon272 11y agoCouldn't this be alleviated with a finger prick method that prevents the droplet from sitting on the surface of the skin before it is collected? (i.e. a tiny needle that reaches below the epidermis to extract a drop of blood)
- learc83 11y agoThe needle breaks the skin and moves through any contaminants that were on the skin's surface--potentially mixing the contaminants with the sample regardless of whether the blood sits on the surface of the skin or not.
- enraged_camel 11y agoIsn't it common practice to wipe the skin with a disenfectant to prevent this very thing? A 60-70% alcohol-based solution will kill the vast majority of germs on the skin.
- learc83 11y agoContaminants don't have to be alive to confuse results. Also many contaminants we're talking about were never alive in the first place.
- firasd 11y agoI wonder if you could apply some substance on the skin or needle so that after the prick it doesn't heal up instantly? Keeps the blood flowing for a few seconds.