I'm Dr. Sanjay Juneja,

hematologist and medical oncologist.

I'm here to answer your questions from the internet.

This is Blood Support.

[upbeat music]

First up, What happens if person gets injected

with the wrong blood type?

It's gonna be really bad

and that's because it recognizes that protein as foreign,

as a virus, and it just goes rogue.

It's just like destroy, destroy, destroy, destroy, destroy.

Generally, we treat it with immediate steroids

and may need to consult some very fancy people

to try to churn the blood and get it right.

We have a question from @paydun.

Do we even know why we have different types of blood...

like really?

And the answer is we don't.

There's basically eight different basic ones

that are different variations.

You can have A, B, O or some combination.

And when we're saying those letters,

it basically reflects an antigen or a protein

on the surface of the red blood cells.

But we do know that certain areas

have more blood types than others.

One of the main reasons

is because of infections and viruses.

For example, malaria likes to get into red blood cells

and basically cause you all that sickness if you are type A.

So you'll see more type O in those areas

because they were less likely to die.

Next question from Ryan Rodriguez.

Could blood actually spray and/or jettison

from the human body as is sometimes seen

in movies, shows, and games?

The answer is yes.

If you cut an artery, that pressure is higher.

An artery is your oxygenated blood.

It's the stuff that just got the oxygen from the lungs

and is being pumped out.

It's the top number on your blood pressure,

and it carries oxygen and all the fuel and the stuff

that all your cells need to the tissue.

But when you're drawing blood

and the stuff that's the veins,

it shouldn't be at the pressure to be shooting out

at somebody.

Veins are a passive, more limpy process

because it's the bottom number of millimeters of mercury

on your blood pressure,

and it's the blood that is now deoxygenated.

It's done its job and the red blood cells are coming back

to get more oxygen into your lungs.

@Garrett_Sandlin, What the fuck is a hematologist...

Lol.

A very nerdy person usually that studies blood.

When we think of blood, you think of the the red stuff

and it carries oxygen, but it's actually far more than that.

It's constituted predominantly by three things.

Red blood cells, right? They carry oxygen.

They're like, Ooh, gimme oxygen, lungs

and then they go deliver it to the rest of your body.

But the other parts are white blood cells,

the antibody stuff that you hear about vaccines

that live for years.

The third part is platelets. Platelets help you clot.

They're the reason that when you get a cut,

it actually closes up.

Those are generally the three parts

and then the last one is what's called plasma.

And plasma is this beautiful harmony,

balance of taking care of things when it comes to clotting

and should you clot more, should you clot less

and fight infections.

Point being, there's a reason

that you have to do all of internal medicine for three years

and then an additional one or two years in hematology

just to understand how complicated this is.

Next question by Dr.Moxie Coms open,

What exactly is a hemorrhage?

A hemorrhage is a general term to just mean bleeding.

So you could be hemorrhaging, technically,

from your arm from a cut,

but we usually use it in a colloquial sense to mean a lot.

@spiidyy, What's the difference between red blood cells

and white blood cells?

Red blood cells are pretty much all the same thing

in your body.

They carry oxygen.

Oxygen is the fuel on every cell in your body.

White blood cells have all different kinds.

There's neutrophils and lymphocytes.

Neutrophils are stuff that go up with bacterial infection

and fight things when you inhale them

all the time walking around.

And then you have the lymphocytes,

which is all that antibody stuff.

Antibodies are smarter when it comes

to attacking pathogens or viruses and stuff.

That's why you get vaccines when you're young.

They're already prepped and ready.

They're hardwired because you gave them the wanted poster.

They're kind of smarter marines

and that's the whole concept behind vaccines

as well as just getting an infection.

Posted by ChampionK448, How do scabs work?

Scabs are basically the evidence of the clotting process.

The moment the endothelium,

that is the inner lining of the red blood vessel,

when it feels injury, it sends a whole cascade of markers

and signals and say, Yo, I'm like, I'm cut here.

And then the platelets, which are the things that float

in your bloodstream, they're actually yellow,

which is why they're found in plasma.

They basically are the endothelium,

the inside lining of the blood vessel floating around.

And then they go to that point of the injury

and then they get out these little tentacles

and they latch on and that's the platelet plug

and they start sending out a lot of signals.

Yo, yo, come. We need to regenerate this.

So when that platelet formation starts,

then you start getting a blood clot after that.

That is the immediate process that's happening

to quickly restore that as fast as possible.

Next question from @MugishaElliot, My doctor friends,

what causes a blood clot and how does it kill somebody?

A blood clot is actually a complicated downstream series

of events to make something that's hard

and put together, that's clotting.

We need to be able to clot, right, all the time.

I mean if you get a cut, you need to be able to clot it.

However, you can have a clot that comes out randomly.

This is an example of what happens if you get a blood clot.

Especially if this blood vessel was in your lungs,

a pulmonary embolism,

and you blocked the blood flow entirely

to be able to get oxygenated,

you're in big trouble.

Next question, @McCoyee,

What happens when you centrifuge blood?

We are basically spinning down the blood.

The blood has multiple components.

It has red blood cells that carry oxygen, it has plasma,

it has white blood cells that fight infection,

and it has those platelets.

So today, we'll be using an example,

back like science class, of oil, vinegar, and dye.

When you take that uniform solution

and you want to isolate your plasma,

if you put into the machine

and then the centripetal force forces the densest thing

to the outside, that's why it's angled.

And now you have a nice separation.

You have what looks like the plasma at the top,

which is clear, and that's the stuff

that if you get platelets

or you're getting the plasma stuff in a hospital,

you'll notice that the bag is yellow

and it's different than when you're getting red blood cells.

Next question, @ihatetrace,

Hey Siri, there's still blood in my urine.

How much is too much?

If you were seeing blood in your urine,

that's too much.

Even having red blood cells that you can't see

called microscopic hematuria

Any much is too much if you can see it.

@jacquesderridad, Is blood really blue in the body?

The blue concept is inaccurate.

The veins appear blue, which are the lining

or the piping that has the blood in it.

@uMthonos, How does the blood pressure arm thing work?

What a blood pressure cuff is doing

is assessing what pressure is your heart pumping at.

The left side of your heart is pumping blood

all throughout your body.

You continue to elevate the pressure

until the pressure in the cuff

is more than the pressure of your heart

pushing the blood to the end of your fingers,

and then you start to come down.

So you're at 180, 170, 160, 150, 140,

and then all of a sudden you hear that top number

of that strong left ventricle in your heart

able to start pushing.

That's when you know your top number.

And eventually, the beat fades away. Why?

Because the bottom number is the passive way that our blood

after it is done and given the oxygen to everything,

it needs to come back to the heart to get more oxygen.

By Deft with many Ts, Why do people faint

when they see blood?

The reason that we pass out in general

is because if our blood vessels dilate,

which is what's happening

when you see something that's scary,

and your brain is not receiving enough blood anymore.

So the theory is, through evolution,

our bodies learned that I'm having trouble getting blood

with oxygen and fuel to the most important organ in my body,

the least I can do is completely collapse

so I don't have to combat Newton's gravitational law

like downward.

Next question by Makala Phillips @98kala,

Every time I'm on my period,

I'm so confused how girls can bleed so much and still live.

Your bone marrow is constantly making blood.

And so if you were to check a reticulocyte,

which is a baby blood vessel, it's cute,

it's actually bigger than normal,

you'll see that during and after your cycle,

that reticulocyte count should be up.

That's showing that your bone marrow is spitting out

and trying to accommodate for the circumstances.

Because your red blood cells all only live

about 90 to 120 days so it's always doing it

and it knows when you need more.

@sirjeff32, Can someone die from high blood pressure?

Like this is a real question.

The answer is yes. Two times over.

You can die from acutely high blood pressure,

which means at that moment.

Too much, you know, Adderall, cocaine, methamphetamines

because they raise your blood pressure.

Now the blood pressure itself will not, you know,

kill someone,

but those blood vessels that are taking

that insult from the heart, it's 200, it's 220,

then if it cracks and pops open

now you're bleeding into your brain or anywhere else

and that can cause, obviously, immediate deaths.

But then over time, the reason people are so obsessive

about it is because that injury

from that flow of that blood pressure

over and over and over eventually start causing

this kind of stuff, plaque burdens and a little injury,

and then now this coronary artery disease

or cardiovascular disease is starting to clog up everything.

And remember the way that your heart functions,

your brain functions, your kidneys function,

all the things that are called vital organs

start losing the amount of circulating blood

and oxygen they need to operate correctly.

Next question from @MarkBski,

How often are new blood cells made

and what are they made from?

They're all made, for the most part, in the same place.

They are made in the same place and that's your bone marrow.

When you break a chicken bone, you see that dark,

you know, ruddy stuff.

It's in the bone, within the bone itself,

and they're basically prompted by stem cells

and your stem cells say, Hey, I need some more.

Your red blood cells live about 90 to 120 days.

So when they're getting kind of recycled in this spleen

and old, you make new ones from the bone marrow.

This next question from Ari, Weird question,

does anyone know if low white blood cell count

is ever serious?

If it deviates from your baseline

and you see this massive drop,

then that, generally, is thought to be something

to investigate or be serious.

But what's crazy is in Black Americans

and as well as some other minority groups,

ranges we have for normal are actually based

for the most part on Caucasian Americans

from like the 1980s.

They took 10,000 healthy people and were like

You look really healthy, let's see what your number is

and said, This is what we consider normal.

So up to one out of three to one out of five Black Americans

will actually repeatedly look low

on the white blood cell count,

but more specifically on the neutrophils.

That's something to be said about ranges.

So if you're ethnic and you're using the range

of someone in America of what our cutoffs are,

realize that we only know normal by sampling people

and saying You look healthy

and this is what we think is normal.

@Enoch_Nyanz, What are the signs of leukemia?

Leukemia is when something has gone very wrong,

very, very wrong in your bone marrow.

Your bone marrow has like a hierarchy and pecking order.

You have just the number of cells that you need

to differentiate and mature and grow.

When leukemia happens is it's not regulated anymore.

Cancer means unregulated cell growth.

If you have acute leukemia, market exhaustion,

market fatigue, your blood count is like super low,

and you may be losing weight,

and you're exquisitely sensitive to getting infections.

And oftentimes, you'll notice you start getting, you know,

spots of little pinpoint red dots out of nowhere

because your platelets are so low.

@Jinnah2Imran, Why do mosquitoes prefer some people,

but wouldn't bite others?

One of the main things that they're theorizing

is if you have more CO2,

which is bicarbonate, in your blood,

apparently mosquitoes can kind of almost sense

in the blood that has more bicarbonate.

Also, depending on what type you have, supposedly,

that may kind of trigger or have a predilection

on what mosquitoes favor.

But the truth is it's quite complicated

and we all wish that Noah

had just slapped those two mosquitoes.

Well, that's all the questions.

I really hope you learned something

and appreciate the blood system more.

We'll see you next time.