IV air bubble compensation

[JL123]

Hello, I hope someone can help me with this question. I am a nursing student and it's been bothering me for a long time. What happens to air that enters the blood stream through a peripheral IV? I understand how the air can become an embolism, but my question is related to the scientific or physiologic mechanism that happens in the body that prevents complications. I have seen many air bubbles enter through PIVs and the people are fine. I just wonder, what really happens to the bubbles once in the body?

*Does the air bubble get absorbed somehow in the body? If so, how? Or, how does the body get rid of the small bubbles?

I've read in other forums that the lungs filter the bubbles but I don't understand exactly how, since I thought the blood stays separate from actual air in the alveoli. And also, the bubble would have to pass the right heart before getting to the lungs.

I would appreciate any explanation! Thank you!

[barbshortt]

of course, you cannot use daytonite's method when you are running chemo through an IV line....you can either pull the air out into a syringe, or push the air back up into the bag with compatible fluid (NS or D5W, depending on the chemo).

[RNin2007]

I have a friend who was a vet tech for 17 years. She asked the same question of her vet...he proceeded to inject 30 cc's of air directly into an IV line of a KITTEN to show her nothing would happen. Nothing happened...but yikes, lol. I can't imagine that was necessarily *good* for the kitten, and this was many years ago...but your reply was interesting Daytonite - thank you.

~J

[anc33]

Now, having said that doesn't give nurses free rein to permit this to happen. Efforts should be taken to prevent air from getting into the IV line and the patient's vein. You should know the immediate first aid for a large amount of air that enters the blood stream: turn the patient onto their left side with the head of the bed elevated to trap the air bubble in the upper right atrium of the heart.

I believe Trendelenburg is the proper bed position for a patient with a suspected air embolism.

[Mulan]

I believe Trendelenburg is the proper bed position for a patient with a suspected air embolism.

That is my understanding as well.

[JL123]

oh yes head of the bed down, because then the air would be trapped in the R. atrium because it is lighter than blood. I didn't read that reply carefully. Thanks!

[augigi, CNS]

I think it's Trendelenburg so the air is trapped in the right ventricular apex. If you were head up, you could be in trouble with a cerebral embolus is the air is ejected.

[Balder_LPN, LPN]

I'm a nursing student and a diving intructor. In regards to trendelenburg position, we no longer use this as first aid for a diver who has embolised or is suffering DCS.

I did find this at eMedicine - Dysbarism : Article by Stephen A Pulley, DO

"Do not put the patient into the Trendelenburg position.Placing the patient into a head-down, Trendelenburg position previously was considered standard in the ED management of diving injuries to prevent cerebral gas embolization.

A more recent study suggests that this practice should be abandoned. The process actually increases intracranial pressure and exacerbates injury to the blood-brain barrier"

and from Effect of the Trendelenburg position on the distribution of arterial air emboli in dogs -- Butler et al. 45 (2): 198 -- The Annals of Thoracic Surgery

"Trendelenburg position does not prevent arterial bubbles from reaching the brain. "

Here is a interesting note of a pt injected with 90ML of air, admitted to hosp with dyspnea etc, rapidly recovered with no treatmet Ten Foot Stop News Blog » Venous Air Embolism

Now my questions are...Why does the literature on diving focus on keeping the bubbles away from the brain, and seems to ignore the anatomy of the heart as brought up in some of these posts?

Also, if I (or someone I am with) suffer AGE or DCS while diving do we use trandelenberg or not?

one more.... No one here is distinguishing between AGE and VAE ie arteries or veins, is there a difference in treatment.

[anc33]

Insults secondary to decompression are very different from the ones we generally see in a hospital setting. In diving situations, depressurization causes nitrogen in the body to come out of solution. The gas bubbles formed can be found throughout the body unlike insults where we know where the air entered the body (ie. while removing a central line). That may be the reason why the head down position is not advised after diving injuries.

[penguin2]

I like the explanation I heard a cardiologist give to a patient once, who was stressing over a few air bubbles: It would take a whole IV tubing full of air w/a great force behind it pushing it thru to cause any harm.

[jojotoo, RN]

You should know the immediate first aid for a large amount of air that enters the blood stream: turn the patient onto their left side with the head of the bed elevated to trap the air bubble in the upper right atrium of the heart.

So once you put the pt in this position and the air is "trapped" - then what?

[Balder_LPN, LPN]

Insults secondary to decompression are very different from the ones we generally see in a hospital setting. In diving situations, depressurization causes nitrogen in the body to come out of solution. The gas bubbles formed can be found throughout the body unlike insults where we know where the air entered the body (ie. while removing a central line). That may be the reason why the head down position is not advised after diving injuries.

Note too that the presence of nitrogen bubbles in the blood is termed DCS (decompression sickness), and most of the nitorgen will initially be found in the veins as the pressure is slightly lower than the arteries. A diver may also suffer AGE (arterial gas embolism) when holding their breath on ascent, forcing air through the membrane of the alveoli and therefore placing the embolism into the artery. AGE is usually a more immediate threat to life than DCS. We are reccomended not to use trendelenberg for either with divers.

What about clots formed around the gas bubbles, this is not addressed either by trandelenberg?

I still dont get why you do it in the hospital, but not for divers with the same type of injury.

Also did you know that the divemaster/instructor is taught to accompany the injured diver to the hospital to (attempt to) ensure such things as ; medivac maintains lowest possible altitude, administration of 100% O2, no trandelenberg, and immediate recompression therapy? This may be old fashioned, but the dive industry doesnt think that healthcare teams know how to properly treat a diving injury.

[MurseNeutron]

how many licks does it take to get to the center of a tootsie pop? my standpoint would probably be to just not put any air in the patient, lol.

im at work right now so i asked one of the high speed ICU docs i work with how they would remove air from the patient after you caught the embolism in the right atrium of the heart. he stated that you should actually put the patient in trandelenberg position on the right side with the chest slightly up catching the embolism on the apex of the heart, which still allows blood to flow normally through.

He mentioned that if held in that position long enough, eventually most amounts would be broken down; considering a main reason of blood is to carry oxygen. If they had to remove the embolism it would be pulled out with a longer triple lumen. say a 30 cm cath, which actually is used for nothing impaticular, but removing air due to its length. they would thread the catheter through and pull the air out. pretty cool. he also said that 10ccs of air really wouldnt do anything, which is the basic length of an IV line.

Now if you were to inject it arterially you probably would want to start looking for another profession or a good lawyer.