The skin is pretty elastic and will wipe away any blood on the tip of the needle. Which is also why in healthy people needle sites don’t tend to bleed much if at all.
Dexter is a fictional story, it is not real. The needles in it are props.
In real life however, the needle is so small that when it pulls out of your body, your elastic skin hugs around the needle essentially ‘wiping the blood’ off the needle..
It’s also that once it pulls out, depending on how good the one administering is, there will not be any external bleeding either.
There’s no visible blood because the needle is polished stainless steel; your skin just wipes it off. There is, however, some blood, which is why those that use illegal drugs very-often get (very expensive) infections when sharing needles.
[Insert rant about how needle-exchange programs are a spectacular idea, both saving addicts’ lives and saving money, and actively restricting access to needles is inhumane, cruel, and stupidly counter-productive. At the very least, syringes should be easy to at least purchase.]
ELI5: your skin has layers. Most shots are done in layers without many blood vessels, so they rarely cause bleeding, and if they do it’s very minor. The needles are so small that you wouldn’t see blood on them anyway.
ELI18: Most injections are done subcutaneous or intramusucular. Both of these are designed to avoid blood vessels and inject medication where it will diffuse slowly into neighboring tissues. You may see the provider aspirate (pull back on) the plunger to make sure there’s no blood return, to ensure that the injection hasn’t hit or ruptured a blood vessel. On top of that, the gauge (25-30 usually) of needle used is usually quite small. Under a microscope there may be blood cells on the metal, but you won’t see the residue with the naked eye. Your body naturally wipes the needle as it’s removed.
Getting an intravenous injection (into the vein) is different. Your goal is to see a blood return, usually in the form of a flash chamber, to make sure your catheter is in the correct area before placement. You may sometimes see blood on a large diameter IV needle like a 14 or 16ga, usually around the tip. Again, this is designed to enter into a blood vessel, so its quite obvious.
Most tissue has very small blood vessels. Big blood vessels are useful for moving lots of blood around, but the only way to get its stuff to the cells that need it is through super tiny blood vessels that make up the vast majority of the blood vessels in the body. As long as you don’t hit one of the rarer big blood vessels with a needle, the tiny ones don’t bleed enough to be an issue.
There’s trace amounts but basically, you’re injecting a fluid so you’re sort of pushing blood away from the needle. And you sort of scrape blood off the needle as you retract it pay the skin layers, which are flexible and abrasive.
Because all your fear is stored in the blood. Your blood is afraid of needles.
You know how when someone goes pale, people say they look like they’ve seen a ghost? That’s because blood is afraid of ghosts and runs away to hide.
Obviously this isn’t a serious answer. But if an actual 5 year old asked me that question, I’d probably tell them this. It’s a good thing I don’t have kids
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Because when a shot of given you are pushing fluid out of the needle. Any blood that got in the needle when first inserted gets pushed out with it.
The skin is pretty elastic and will wipe away any blood on the tip of the needle. Which is also why in healthy people needle sites don’t tend to bleed much if at all.
Dexter is a fictional story, it is not real. The needles in it are props.
In real life however, the needle is so small that when it pulls out of your body, your elastic skin hugs around the needle essentially ‘wiping the blood’ off the needle..
It’s also that once it pulls out, depending on how good the one administering is, there will not be any external bleeding either.
There’s no visible blood because the needle is polished stainless steel; your skin just wipes it off. There is, however, some blood, which is why those that use illegal drugs very-often get (very expensive) infections when sharing needles.
[Insert rant about how needle-exchange programs are a spectacular idea, both saving addicts’ lives and saving money, and actively restricting access to needles is inhumane, cruel, and stupidly counter-productive. At the very least, syringes should be easy to at least purchase.]
ELI5: your skin has layers. Most shots are done in layers without many blood vessels, so they rarely cause bleeding, and if they do it’s very minor. The needles are so small that you wouldn’t see blood on them anyway.
ELI18: Most injections are done subcutaneous or intramusucular. Both of these are designed to avoid blood vessels and inject medication where it will diffuse slowly into neighboring tissues. You may see the provider aspirate (pull back on) the plunger to make sure there’s no blood return, to ensure that the injection hasn’t hit or ruptured a blood vessel. On top of that, the gauge (25-30 usually) of needle used is usually quite small. Under a microscope there may be blood cells on the metal, but you won’t see the residue with the naked eye. Your body naturally wipes the needle as it’s removed.
Getting an intravenous injection (into the vein) is different. Your goal is to see a blood return, usually in the form of a flash chamber, to make sure your catheter is in the correct area before placement. You may sometimes see blood on a large diameter IV needle like a 14 or 16ga, usually around the tip. Again, this is designed to enter into a blood vessel, so its quite obvious.
10 year Paramedic/Medical provider.
Most tissue has very small blood vessels. Big blood vessels are useful for moving lots of blood around, but the only way to get its stuff to the cells that need it is through super tiny blood vessels that make up the vast majority of the blood vessels in the body. As long as you don’t hit one of the rarer big blood vessels with a needle, the tiny ones don’t bleed enough to be an issue.
There’s trace amounts but basically, you’re injecting a fluid so you’re sort of pushing blood away from the needle. And you sort of scrape blood off the needle as you retract it pay the skin layers, which are flexible and abrasive.
Because all your fear is stored in the blood. Your blood is afraid of needles.
You know how when someone goes pale, people say they look like they’ve seen a ghost? That’s because blood is afraid of ghosts and runs away to hide.
Obviously this isn’t a serious answer. But if an actual 5 year old asked me that question, I’d probably tell them this. It’s a good thing I don’t have kids
I got yelled at in bootcamp, after receiving 5 vaccines, for bleeding. 🙁
I am a diabetic. Two shots a day in the stomach for something like twenty years. Never seen any blood at all.