Thursday, May 10, 2018

First Aid: IVs

Hour 8

Today's lesson is on intravenous lines, or IVs.

Nota bene, please, the differences between intravenous access (which the well-dispersed knowing of how to obtain is a good thing) and intravenous therapy (the knowing and doing of which, in most states, requires paramedic or RN-levels of medical training, without which you'll be more of a danger than an asset, in any sense).

References: Warrior Skills Level 1 , pp. 3-44 through 3-49

Go over the steps in the above reference; making sure you understand them.

Then watch this video:

That's all there is to it.
I can teach a high-functioning orangutan to start IVs, if their eyes, ears, and hands work to the 90th percentile of awake, alert, oriented, standard vision, and moderate eye-hand co-ordination.

That being said, the things you need to know, from someone who's probably started 30-50K IVs so far:

1) Get all your sh*t together before you start. Assemble it, spike IV bags, pre-flush J-loops, etc. It's a lot easier to do with two hands, than trying to pull things apart or put them together with one hand is when you're in the middle of placing and securing the IV.

FTR, to start an IV saline lock, you need:
Alcohol or betadine swab(s)
Saline syringe flush
IV Cap or short 3-4" J-loop of tubing with included cap
Tegaderm or equivalent transparent site cover
a couple of gauze 2"x2"s for mopping up messes
at least one IV catheter needle (18G or 20G preferably) 
medical tape to secure J-loop and/or IV, in addition to Tegaderm 
 2) Any big vein between the knuckles and the armpits will work. Your go-to first choice is always the inside of either elbow, which is known as the antecubital (AC) space. Almost everyone has a big vein (or three) there on either side, especially military-age males. The veins there don't have as many nerve endings as anyone's hand does, so they hurt less there. More fluid can be pushed more rapidly (including IV contrast for CTs, which isn't your problem, but if you don't get the veins there, and they need a CT with injectable contrast later, it will be your patients problem when they require another stick), which makes it better for a host of reasons. Another of which is that medication pushed into the left AC will reach the heart faster (5 seconds or so, depending), which may be exactly what they need in critical cases for some drugs. Take any vein you can get when you need one, but go for the A/Cs on either side as your first choice.

3) IV catheter needles come in sizes, which are gauges.
They work just like shotguns: littler numbers mean bigger barrels.
14g and 16g: horse needles. 14g is used for blood extraction during transfusion, which has to go fast. 16g is for trauma, when you need to dump a lot of fluid or blood in rapidly. (Or, because the patient pissed you off, and you want it to hurt. I hear.)
18G Think of this as "Large". If you can get an 18, do it.
20G "Medium". Good enough, for medication, blood transfusion going in, etc.
22G "Small". If it's all you can get, better than nothing. May be too small for blood transfusion (blood may hemolyze, i.e. red cells "explode", which negates the point of the transfusion, but it can get fluid and medication into a patient, albeit very slowly.)
24G "Extra-small". Used for pediatric patients down to toddlers, and grown up geriatrics with piss-poor "little old lady" vasculature.
There are other sizes, but 18G and 20G, along with occasional 22G, should be 95% of what you'll ever use, even as a nurse in a hospital, other than pediatric settings.
The gauges have (mostly universal) standard color codes on the hubs:
18G: Green
20G: Pink
22G: Blue

4) Letting an arm dangle below the heart level gets gravity working on your side to fluff up your target before you poke.
You can also gently thwap the vein to fluff it up briefly just before you stick.

5) The flat bevel of the IV should be up (away from the patient/vein) when you begin.

6) Most IVs have a flash chamber, which lets you see that the tip of the needle is in the vein.
But the plastic catheter, which is the point of the exercise, isn't inside the vein yet. Advance it with your free hand - or your dominant index finger if you've got the "good" kinds of IVs that'll let you do that. Note that some of them are some low-budget p.o.s. bought by low-bidding purchasing A-holes who don't have to use them. Learn how to use what you've got.
Slide the catheter into the vein, as far as it will go.

7) Your veins (and everyone else's) have valves inside them, which keeps all your blood from pooling in your feet when you stand up. When the plastic catheter straw hits one, you won't go any farther. You may have the catheter in far enough to work, and secure it. Or, it may dislodge later on, after arm movement, or Murphy f**s up your careful work, because it wasn't in the vein very far to begin with. You can't help that, but you can (and must) monitor how things are infusing. This is why we check IV sites during infusions, to make sure we're not pumping up the surrounding tissue painfully full of fluid, blood products, and/or medicine that's not going where we want it to be. Some medicines burn or cause other tissue damage outside the veins, so this is a big deal.

8) Once you've got an IV inserted into a site, and capped the catheter, secure the hell out of it. Think of "secure" the way a Marine or Ranger platoon would if it was guarding a bank. The patient may be moved, jostled, struggle, etc. They may be bloody or sweaty, now, and/or later on. The IV site you establish may be the only way to get life-sustaining fluid and medication into them. Or, not. So once you get one, make sure it isn't going to get yanked loose, sweated off, or otherwise fornicated up by Murphy, Fate, or dumbasses down the line. Doing this will save lives.

9) Bubbles in IVs aren't a problem, unless they are. Anything the size of the lower-case 'o' in this sentence or smaller, will simply absorb into circulation. Tubing with inches to three feet of air will kill your patient when the air embolism reaches the heart, and it strokes out, and can't pass the bubble. Get the air out of the tubing, before you connect it to the patient.

10) Make sure you took the tourniquet off the arm after you started the IV.
Make sure you took the tourniquet off the arm after you tried to start an IV, and failed.
And make sure everyone else took the tourniquet off when they tried too. Tourniquets get left on. A few minutes is no big deal in the grand scheme of life (except that nothing is getting into the patient through the IV site, and their arm is getting number and bluer). An hour is another story. Check, and check again.

11) Keep the rat-nest of medical sh*t on any patient simple. If the IV is on the left side, hang the bag on the left side of the patient. And so on.

12) You can start IVs on feet and legs too. If it's attached to the patient, it'll still work. Because sometimes, unfortunately, they may not have arms. Or they may have them, but have no good veins in them. Use what you've got.

13) There are many adjuncts to IVs. EJ/IJ (external/internal jugular venous access), IOs (intraosseous - i.e. into the bone - access), and so on. They are beyond the scope of this material, but nothing precludes you from additional self-education on the subject.

14) Record the time and site of any working IV on the TCCC patient card.
Put a label (or a piece of white medical tape) on IV tubing, labeling what's going in it.

15) If you pull the spike out of an IV bag (because the bag is/is almost empty) you can either clamp the line first, or make the switch to another bag with the spike rapidly, before the fluid drips out of the drip chamber. This saves additional tubing usage and conserves supplies.

16) If you have the option, IV tubing that requires no needles for med admin or interconnection is both standard-of-care in the real world, and vastly preferable, because of lesser risks of needle sticks, and fewer sharps to dispose of. Use what you've got, but needleless is a better deal.

17) Tubing has a drip rate (abbreviated as gt. and gtts. in medical terminology, from drop/drops) noted in drips per milliliter (it will be marked on the packaging or labeled on the tubing).
There is a handy table in the back of the TCCC Guidelines for drips per minute for a given rate of fluid per hour, for the three most common gtt rates of IV tubing encountered. And several different volumes. That's nice, and useful.
Even better is this formula, courtesy of a Vietnam Army surgical nurse, and one of my professors of nursing back in the day:
X÷60/Y = Z
X= amount of fluid to be given, in mls
60= constant
Y=gtts per ml rating of tubing
Z= answer in drips (gtts)/minute
MLs of fluid per hour ÷  60/tubing drip rate per ml  = drips per minute.
E.g. 200ml of fluid per hour ÷ 60/15 gtt tubing = 50 gtts/min.
{200 ÷ (60/15)=200/4=50 gtts/min}
That number (gtts/minute) breaks down as well, as follows.
50 drops in 60 seconds means a little slower than 1/second.
If you adjust the sliding clamp until your drops are hitting a little slower than saying " a thousand one(Drip!)" and you watch them for several seconds, you've set a 200 mL/hr rate in about five seconds, with no notebook, no calculator, and no pump.
Walk away.
Check the bag in half an hour, and see if you've dumped 100 ml of fluid, or not, but odds are, you'll be right on.

Second example
100 mls per hour with 10gtt tubing
100 ÷ 60/10 = 100/6 = 16.66etc.
16.6 drips in 60 seconds is a hair faster than one drip every 4 seconds.
"A thousand one, a thousand two, a thousand three, and thousand four (Drip!)"
Adjust that so it's constant over 8-16 seconds, then walk away.
(Or, if you're anal-retentive, and have lots of time while treating patients, count out the drops for a full minute.)

X÷60/Y = Z
X= amount of fluid to be given, in mls
60= constant
Y=gtts per ml rating of tubing
Z= answer in drips (gtts)/minute

Then figure out how long per drop for a minute, and you can set your tubing manually, with a calibrated eyeball, and the ability to count.

In sharing that calculation formula, I've just condensed two months of nursing IV pharmacology dosing into a few small paragraphs.
For free. 
You're welcome.

That's what you need to do IV access.
For IV therapy, you need 6-48 months of paramedic or RN training, or an apocalypse, and the suitable self-study texts.
And to do it, you'll need metric buttloads of IV fluids and medications, and a room full of IV supplies.

But almost no one, anywhere, will ever bitch if you've sent them a patient with a properly started and well-secured working IV access point.
Usually, they just say "Thanks", and get on with their business.

Final note: You cannot, I repeat CANNOT, learn this skill task by reading about it.
Or practicing on IV practice arms (which have veins in them the size of freeway on-ramps, unlike actual patients.)

The ONLY way to learn this, properly and well, is to actually DO it, on willing, living, breathing volunteers, over and over again, under the eyes-on supervision of people who know how to do it already.

And yet the US Army thinks it important enough that it's now an all-hands everybody-learns-it skill, for every single GED-graduate swinging Richard in the Army.

So you can take it from me that it is officially not rocket science.
Get trained.


Anonymous said...

Great summary and lesson. Brings back training of almost 30 (!) years ago.
I was fortunate enough that when my friend (an 18D) was giving my son CLS training one-on-one (thanks once more Doc!!!) and was anticipating being the "subject" for the IV phase one of our techs came in brutally hung-over and begging for some fluids. HE got stuck instead of me - couple-three times IIRC - and was still OK with it.
I've still got my personal set and half-liter bags that are current but it'd gonna have to be BAD before I attempt it again, even after reviewing the EXCELLENT explanation you wrote and the video your Army made.
Boat Guy

Our Corpsman (RIP Doc) did make the point that as long as we got a line in whether we ran out of fluids before we got our guy back to help that was still a GOOD THING.

TFA303 said...

I'm getting a ton out of this series, please keep it up!

By distinguishing between IV Access and Treatment in terms of the qualifications required for each, is it safe to say that if you're not with someone qualified to determine proper treatment, don't bother obtaining IV access for a patient, as you're more likely to do harm than good by guessing what kind of treatment he needs?

Many thanks,

Aesop said...

Rule of Thumb: Anyone who needs* medevac/a trip to the ER, probably needs an IV, and is probably going to get one 90% of the time.
The main exceptions are timewasters with sniffles/sore throats, and the people with sprains rather than fractures, and superficial or minor lacerations.

Everybody else is going to need/want access for pain control, antibiotics, fluid therapy, baseline lab tests, and much more.

If you can determine that your patient needs a hospital or medevac, they probably meet criteria for an IV, after more serious problems have been dealt with.

Which is doubtless why Big Green now wants every swinging Richard who signs up to know how to do the skill, rather than keeping it a medic-or-above-only skillset.

*{Note I said needs, and not goes.}