Why does a bubble in a bloodstream cause your body to go haywire?
In: 78
Put air in an oil line and see what the pump does… Same concept.
It can create a situation where the blood no longer flows correctly. No blood, no oxygen (or nutrients/energy/cleaning).
The problem? Squeezing gas along is a hell of a lot more work than liquid. Squeeze a liquid it forces itself along is doesn’t compress in actual volume much at all, gas/air however does.
Now as long as the gas is fully pushed by the liquid it works fine (see big vessels), but if it gets to a point where compression is doing the majority of the driving work, or where the liquid has another path and the bubble fills a path this creates a problem especially in smaller, higher resistance paths.
You may have heard of bleeding a pump – that is the process to remove air.
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The route of the problem though – gases compress in volume you may as well consider that liquids don’t.
Air bubbles can freely travel through large blood vessels but eventually, the vessels get narrower and narrower. The air bubble will eventually get stuck in smaller vessels, blocking blood flow to wherever the vessel delivers blood. This is known as an air embolism.
If the blockage is in the brain, lungs, or heart, the effects can be deadly. Blockages elsewhere can still cause damage from the lack of blood.
I once got sick when on vacation. (Diarrhea, vomiting.) Part of the treatment at the Dr office was a fluid IV. But…. the Dr and the nurse were not careful and I could see bubbles in the tube. I pointed it out to them and they flicked the tube and messed with it a bit and still had bubbles. They didn’t offer to do anything different. (There were like…. three.) I said….. “That’s OK, I don’t need the IV. Can you remove it, please?” and noped out of there.
Imagine your blood as a tube full of marbles. Imagine the heart as pushing on those marbles.
Now imagine taking one of the marbles out and replacing it with a small balloon (an air bubble).
It should be easy to envisage how this will reduce the effectiveness of pusing the blood around. There will simply be less force on everything after the balloon, because the balloon can squish. Marbles (just like blood) can’t squish.
Paramedic here-I’ve had this convo with an interventional cardiologist after he purposely foamed up some blood and injected it into cath line…
He said that he did that so that he could see the blood flow (bubbles show on the Xray video)through the heart. He explained that the air bubbles will dissipate as they pass through the lungs and that it would need to be a fairly large volume of air to cause any problems.
In order to cause any problems, there would need to be a large volume of air in a standard IV line, like more than 20 inches, injected into a vein…a few bubbles isn’t going to hurt in a vein. It would cause a problem in an arterial line, though. I don’t think art lines are going to be in place very often in a non-hospital setting
Same basic reason you bleed brake lines, the air bubble can prevent fluid from passing in critical parts of the body. The bubble needs to be pretty significant, multiple cubic centimeters of air to kill you. It is called an air embolism and they are exceedingly rare.
3 to 5 ml/kg of air injected into the circulation is thought to be fatal. However it’s considerably less if the patient has a ‘hole’ in their heart (pfo, asd, vsd).
In a normal heart, such a large volume of air – an air embolism – can get trapped in the right side leading to a sudden and dramatic fall in cardiac output and cardiac arrest. I’ve seen it. The air can also get trapped in the pulmonary circulation and, like a pulmonary embolism, cause a cardiac arrest.
These air emboli can happen by accident. If a patient has a central venous catheter in place and a cap comes off, air can get sucked into the circulation. Brain surgery in the upright position can also cause this as can any upright surgery where veins are open to air.
A hole in the heart connecting the right side to the left side is particularly dangerous. A relatively small volume of air can enter the circulation on the right side, cross to the left side (completely bypassing the lungs) and go into the brain circulation causing a stroke. Again, I’ve seen this too. The worrying thing? 10 – 20% of adults have asymptomatic PFOs (patent foramen ovale). That’s why it’s a good idea to minimise the amount of air that gets into the venous circulation.
Small volumes of air in veins isn’t a big deal, it just goes to the lungs and you breathe it off. Any amount of air in an artery is a big deal; as the vessels become smaller the bubble will eventually block the flow of blood and cause ischemia to the tissue supplied by that vessel. If it’s a vessel that supplies the brain, it causes a stroke (which can range from clinically silent to a large deficit based on where the stroke is and how big etc)
Nurse anesthetist here. Blood vessels and your heart are designed to move blood, a liquid, not air. If about 10cc per kilogram of weight gets into the right side of the heart, it will probably stop pumping blood because its just squeezing air and not moving blood.
However, small bubbles in small blood vessels can stop blood flow in that vessel. This is real bad in the lungs or in the brain. In the brain this can lead to a stroke.
Physician here: without going into too much detail, essentially, as little bubbles float around your vessels, they can block up vessels smaller than the bubbles. In a vein, these can block off vessels in the lungs. In an artery, they can block whatever tissue is at the end of the artery injected. Inject lots of air, and there’s a nonzero chance of a big bubble forming and not breaking down much.
Some gases dissolve well in blood. In fact, CO2 is used to see X-ray anatomy of vessels on patients who can’t get contrast.
Nitrogen is not well dissolved in blood and will create the bubbles we don’t want. Our atmosphere is mostly nitrogen.
Why does a bubble in a bloodstream cause your body to go haywire?
In: 78
Put air in an oil line and see what the pump does… Same concept.
It can create a situation where the blood no longer flows correctly. No blood, no oxygen (or nutrients/energy/cleaning).
The problem? Squeezing gas along is a hell of a lot more work than liquid. Squeeze a liquid it forces itself along is doesn’t compress in actual volume much at all, gas/air however does.
Now as long as the gas is fully pushed by the liquid it works fine (see big vessels), but if it gets to a point where compression is doing the majority of the driving work, or where the liquid has another path and the bubble fills a path this creates a problem especially in smaller, higher resistance paths.
You may have heard of bleeding a pump – that is the process to remove air.
—
The route of the problem though – gases compress in volume you may as well consider that liquids don’t.
Air bubbles can freely travel through large blood vessels but eventually, the vessels get narrower and narrower. The air bubble will eventually get stuck in smaller vessels, blocking blood flow to wherever the vessel delivers blood. This is known as an air embolism.
If the blockage is in the brain, lungs, or heart, the effects can be deadly. Blockages elsewhere can still cause damage from the lack of blood.
I once got sick when on vacation. (Diarrhea, vomiting.) Part of the treatment at the Dr office was a fluid IV. But…. the Dr and the nurse were not careful and I could see bubbles in the tube. I pointed it out to them and they flicked the tube and messed with it a bit and still had bubbles. They didn’t offer to do anything different. (There were like…. three.) I said….. “That’s OK, I don’t need the IV. Can you remove it, please?” and noped out of there.
Imagine your blood as a tube full of marbles. Imagine the heart as pushing on those marbles.
Now imagine taking one of the marbles out and replacing it with a small balloon (an air bubble).
It should be easy to envisage how this will reduce the effectiveness of pusing the blood around. There will simply be less force on everything after the balloon, because the balloon can squish. Marbles (just like blood) can’t squish.
Paramedic here-I’ve had this convo with an interventional cardiologist after he purposely foamed up some blood and injected it into cath line…
He said that he did that so that he could see the blood flow (bubbles show on the Xray video)through the heart. He explained that the air bubbles will dissipate as they pass through the lungs and that it would need to be a fairly large volume of air to cause any problems.
In order to cause any problems, there would need to be a large volume of air in a standard IV line, like more than 20 inches, injected into a vein…a few bubbles isn’t going to hurt in a vein. It would cause a problem in an arterial line, though. I don’t think art lines are going to be in place very often in a non-hospital setting
Same basic reason you bleed brake lines, the air bubble can prevent fluid from passing in critical parts of the body. The bubble needs to be pretty significant, multiple cubic centimeters of air to kill you. It is called an air embolism and they are exceedingly rare.
3 to 5 ml/kg of air injected into the circulation is thought to be fatal. However it’s considerably less if the patient has a ‘hole’ in their heart (pfo, asd, vsd).
In a normal heart, such a large volume of air – an air embolism – can get trapped in the right side leading to a sudden and dramatic fall in cardiac output and cardiac arrest. I’ve seen it. The air can also get trapped in the pulmonary circulation and, like a pulmonary embolism, cause a cardiac arrest.
These air emboli can happen by accident. If a patient has a central venous catheter in place and a cap comes off, air can get sucked into the circulation. Brain surgery in the upright position can also cause this as can any upright surgery where veins are open to air.
A hole in the heart connecting the right side to the left side is particularly dangerous. A relatively small volume of air can enter the circulation on the right side, cross to the left side (completely bypassing the lungs) and go into the brain circulation causing a stroke. Again, I’ve seen this too. The worrying thing? 10 – 20% of adults have asymptomatic PFOs (patent foramen ovale). That’s why it’s a good idea to minimise the amount of air that gets into the venous circulation.
Small volumes of air in veins isn’t a big deal, it just goes to the lungs and you breathe it off. Any amount of air in an artery is a big deal; as the vessels become smaller the bubble will eventually block the flow of blood and cause ischemia to the tissue supplied by that vessel. If it’s a vessel that supplies the brain, it causes a stroke (which can range from clinically silent to a large deficit based on where the stroke is and how big etc)
Nurse anesthetist here. Blood vessels and your heart are designed to move blood, a liquid, not air. If about 10cc per kilogram of weight gets into the right side of the heart, it will probably stop pumping blood because its just squeezing air and not moving blood.
However, small bubbles in small blood vessels can stop blood flow in that vessel. This is real bad in the lungs or in the brain. In the brain this can lead to a stroke.
Physician here: without going into too much detail, essentially, as little bubbles float around your vessels, they can block up vessels smaller than the bubbles. In a vein, these can block off vessels in the lungs. In an artery, they can block whatever tissue is at the end of the artery injected. Inject lots of air, and there’s a nonzero chance of a big bubble forming and not breaking down much.
Some gases dissolve well in blood. In fact, CO2 is used to see X-ray anatomy of vessels on patients who can’t get contrast.
Nitrogen is not well dissolved in blood and will create the bubbles we don’t want. Our atmosphere is mostly nitrogen.
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