Where should the BUBBLE Be

wilbur's mom · Mar 8, 2008

Hi!

I am an old :bugeyes:nursing instructor. A teaching standard is that up to .2cc of air can be drawn into the syringe prior to administration of some types of meds. The air bubble 'floats' to the end away from the needle by rule of gravity and is intended to purge the tissue track of the med, (in this case due to the caustic nature of heparin and lovenox), and minimize leakage and bruising. However, lovenox comes PREFILLED with this nitrogen bubble, and as noted, is not to be purged prior to injection. An additional bubble of room air can be drawn up and ADDED to the med in the syringe, or in a prefill, drawn in just before giving it. Note that the length of needle for SQ injections can vary, based on the size of the patient. And site. The requirement is not using a certain length of needle, but seeing the pt. and injecting into the sq tissue. A thin pt, perhaps use a 1/2 inch needle. A heavy pt, perhaps a 1 inch. And injecting at a 90 degree angle, straight in is fine, or at a 45 degree angle if you only have a longer IM needle, or assess that the pt is thinner than you thought so you change your angle as you inject. The preferred site for Heparin and Lovenox is the lower abd, at least 1 inch away from the umbilicus. Anterolateral thighs can be used for prolonged therapy needs. Aspiration for sq meds is not necessary as anatomically this tissue doesn't contain vessels. My students worry if they see small amts of bleeding on the prep pad, but this is common and happens if a tiny capillary vessel in the dermis has been nicked on the way by. Pinching up the tissue is an old teaching techinique, and again is not nec. if there is adequate subcutaneous tissue where you are jabbing. In fact, if tenting is necessary, it might be a sign you need to check with the MD, as you can't give any med if you have doubt about the site's safety. I.E. an infiltrated IV, an atrophyied or wasted muscle mass, or lack of sq tissue from prolonged malnutrition.

lsyorke, RN · Mar 8, 2008

I agree. Since I'm the only one saying the air goes in first, heck I may be wrong but I remember the first time I gave it, probably 5 years ago, the package insert said the air goes in first. I'll check on it and get back to you. Sorry for all the confusion.

Air goes in last to "push" the lovenox into deeper sub q tissue and prevent surface bruising, at least that's what our many Lovenox inservices have told us. The package insert just says to "not expel the air"....it isn't specific about location of air bubble prior to injection.

lsyorke, RN · Mar 8, 2008

so, sanofi-aventis, the manufacturer of lovenox is wrong? hum...
the reason for not rubbing the site after the injection is to decrease the incidence of bruising it has nothing to do with the nitrogen.

then they need to teach their drug reps!! every single inservice i've had from the company, which are many, says....liquid then air bubble.

DutchgirlRN, ASN, RN · Mar 8, 2008

then they need to teach their drug reps!!

maybe you could write and suggest this to them?

every single inservice i've had from the company, which are many, says....liquid then air bubble.

it is not an "air bubble" it's nitrogen which is used as a preservative for the lovenox, nothing more, nothing less

grandee3 · Mar 9, 2008

:redbeathe

I agree. Since I'm the only one saying the air goes in first, heck I may be wrong but I remember the first time I gave it, probably 5 years ago, the package insert said the air goes in first. I'll check on it and get back to you. Sorry for all the confusion.

Love ya Dutchgirl! Thanks for admitting you may be wrong. Wish we had more like you:yeah:

Warpster · Mar 20, 2008

I know I'm a little late to this, but using physics and critical thinking skills, the answer should be obvious.

Unless you want to assume a very uncomfortable and embarrassing position and want the patient to do the same, the air bubble will float to the top of the medication, just under the plunger, before you inject it.

That's your answer. There is no rationale for injecting the air first, and it requires gymnastics from people who shouldn't be doing them for you to do so.

DutchgirlRN, ASN, RN · Mar 21, 2008

there is no rationale for injecting the air first, and it requires gymnastics from people who shouldn't be doing them for you to do so.

there is no air bubble, it is nitrogen, not air. that aside, for years when they did recommend the bubble go in first...i gave many a lovenox with the bubble going in first and it did not require any kind of gymnastics on my part or the patients. it was just as easy as injecting it last. fyi.

AirforceRN, RN · Mar 21, 2008

Hydrogen? You mean the highly flammable, even explosive gas hydrogen? Nitrogen I can believe...hydrogen though?

DutchgirlRN, ASN, RN · Mar 21, 2008

hydrogen? you mean the highly flammable, even explosive gas hydrogen? nitrogen i can believe...hydrogen though?

sorry my mistake....i did mean nitrogen :uhoh21: we certainly don't need anymore confusion...