[Top Research-based Tips for IV Access]
This lecture offers research-based tips [Top Research-based Tips for IV Access]
on how to gain IV access. (The subtitles are in English
whereas the audio is in Swedish)>>JONATHAN: I was planning to start with
something dramatic, but I’m a bit nervous actually. Looking out in the audience I can see several experienced nurses and today I, who can’t draw blood am going to tell you, who draw blood every day, about the science of phlebotomy and tourniquets. I was thinking about how to best convey this feeling I have and then I found this picture from an ED. [nurses eat junior physicians] [laughter] So I hope you understand if I’m a bit nervous. [laughter] The first question is:
why talk about intravenous access and tourniquets? And the answer to that is, like the answer
to many other things, 42. Every year we attempt to gain IV access
42 million times just in Sweden. Gaining intravenous access is healthcare’s
most common invasive procedure, and arguably one of its most important,
because if we can’t access veins it becomes very hard to diagnose and treat both common and dangerous medical conditions. My name is Jonathan Ilicki and I’m a physician at the emergency department at the Karolinska University Hospital in Stockholm. A year ago, I participated in an innovation program run by the county council, where my team spent several months studying intravenous access. We interviewed nurses, we did tests and surveys,
we performed an extensive literature review. We looked at everything we could find. And based on that we are now developing an innovative tourniquet which will make it even easier to gain intravenous access. I mention this for two reasons:
Firstly, thanks to support from the County Council and Vinnova, my team has continued to work on this and started a company.
So it’s important that I declare my conflicts of interest in this area. And secondly, during this journey I’ve read
a lot of articles. Without the journey, I wouldn’t have read
the articles. And without the articles I wouldn’t be here
today. And when I’ve told colleagues about the
research I’ve found they’ve told me, and these are quotes: “That was actually really clever” “I’m going to try that next time” And “Jonathan, you’re such a nerd” [laughter] The first thing I realized when I was going
to draw blood for the first time in ten years, is that it is hard. And it’s even harder if you have external
factors making it even harder. That mug you saw in the beginning,
this is the other side of it. And it would be great if we could just remove
all distracting factors, but we can’t, and that’s why gaining IV access
is hard. According to the literature 66-86% of first
attempts at IV access succeed. I also sent out a survey to Swedish practitioners, who responded giving an average of 77%. Many factors affect this.
Some things, like the patient’s age and BMI, are beyond our control. Likewise, in the short term one can’t
quickly change one’s experience level. Other things, such as temperature,
the application of the tourniquet, and other external factors,
are things we can affect and that’s what I’ll be discussing today. But before we start: you can learn
things in different ways. Some things are best learnt by reading, Other things are best learnt by doing. Some things are best learnt through cakes. [laughter] This is a very effective and disgusting way to learn
the Bristol Stool Scale. I do not have a cake with me today, and that’s because IV access
is best learnt by doing. However, practical skills like this can be
augmented by understanding the underlying physiology. So today people use tourniquets and blood
pressure cuffs to gain venous access. Who here prefers cuffs? Ok, a small group there. And who prefers tourniquets? Ok, about fifty-fifty. I think that if I would ask each and every
one of you, most would say that it depends on the patient and the context. In the literature, as well as the interviews
I’ve done, cuffs are perceived to be better in enlarging veins, but are used more rarely
as they are bulky and take more time to use. But is that true? In 2011 a group of researchers studied
this using ultrasound. They studied the venous dilation caused
by cuffs, tourniquets and lowering the arm. They wanted to see if lowering the arm
beneath the heart for 30 seconds, prior to applying the tourniquet or cuff,
caused a greater dilation. This is the dilation with a blood pressure
cuff: an 17% increase in diameter. The tourniquet gave a slightly smaller dilation. Lowering the arm before applying the cuff
cause a similar dilation and using a tourniquet and lowering
the arm gave the smallest dilation. In other words, lowering the arm
decreased the venous dilation. [laughter] This shows why it’s to read the whole study
and not just skim the article. This study didn’t look at the antecubital vein – they studied the basilar vein,
one we don’t commonly use for IV access. And it is possible that the basilar vein’s
particular physiology explains the results, that the lowering somehow affected
or blocked the venous return. They can’t explain it in their discussion,
and in short, neither can I. But according to this data, you should not
lower the patient’s arm if you’re attempting to access the basilar vein. And blood pressure cuffs give a
larger vein than tourniquets. But vein size is not everything. Gaining intravenous
access also depends on how compressable and palpable a vein is. And these guys looked exactly at that. They compared a single tourniquet, double tourniquets I have no idea why [laughter] and a blood pressure cuff. Pardon me?
>>AUDIENCE MEMBER: They were bored.>>JONATHAN: They were bored, yes,
that could explain it. They saw the same thing as the previous study.
The cuff gave a larger vein size as well as a sturdier and more palpable vein.
Two tourniquets came in second place, and a single tourniquet was slightly worse. However, there are two key
questions about their study: Firstly, they don’t specify how long the
tourniquets and cuffs were applied. And secondly, we don’t know if increased
vein size translates to more successful IV attempts. Fortunately, other studies have
looked at that. Nelson studied patients in whom IV access
was difficult. These patients had already had two failed IV attempts and were about
to receive a venous cannula using ultrasound. They compared a tourniquet to a
blood pressure cuff inflated to 150 mm Hg. Using the cuff around 50%
of the attempts succeeded, but with the tourniquet 80%
of the attempts succeeded. It’s easy to think “Wow, there’s our
answer, tourniquets are better”, but if you read the whole study
you’ll see that the failed attempts with the cuff were due to
that patients experienced too much pain, that the high pressure blew the veins,
and that the high pressure made it hard to differentiate between veins and arteries
using ultrasound. The authors themselves suggest that if they would
have used another pressure the results would have been different. Not only that, these IV access
attempts lasted an average of 9 minutes, so you probably can’t extrapolate these results
to the normal IV attempts at our EDs. And their conclusion was that tourniquets
were better than blood pressure cuffs. However, in my opinion, if you think about this study in relation to the common
IV access attempts in our EDs, you can summarize its relevance with one word: meh. [laughter] It doesn’t say a lot. However, if 150mmHg is too high,
which these authors seemed to imply, what pressure is optimal? Our national guidelines say 30-40mmHg,
which is based on an American standard, CLSI. To the best of my knowledge that recommended range
is based on consensus, not on any studies. A few years ago a Japanese group
of researchers looked at this. On the x-axis you have time and on the Y-axis
you have the relative increase in vein area. This is the dilation they got with a cuff
inflated to 20 mmHg. They saw an initial rapid dilation and then
the increase stabilized at around 20%. And this is the effect of 40 mmHg. This is 60mmHg, in other words
an even faster and larger dilation. 80mmHg, a slightly larger dilation. And 100mmHg. That is, 100mmHg gave a worse
dilation than with 80mmHg. And this means three important things: Firstly, the amount of pressure applied matters alot. 60-80mmHg gave the greatest and fastest dilation, which means that the current
recommendations are too low. And you’ll probably want a lower pressure for older
patients who have more fragile veins. In short, this speaks against our current guidelines. Secondly, regardless of what pressure is applied,
most of dilation occurs within 30 seconds. So attempting IV access before that is simply
not giving yourself optimal conditions. So if it’s possible, and it’s not very
urgent, wait 30 seconds to ensure that you get past that first peak. Thirdly: after 60 seconds you only get a
minor increase in venous diameter, so there isn’t any point waiting longer than that. And all this may sound obvious, but it isn’t. We often apply tourniquets
too briefly or too long. Is there anyone here from the Vrinnevi Hospital? Yes, in 2007 Titti Peltonen performed a
study at your emergency department. Two men just raised their hands,
so I don’t think they’re called Titti. They’re shaking their heads [laughter] She studied hemolysis and sampling
through intravenous cannulas, as well as tourniquet time. She saw that people
applied tourniquets between 1 second to 7 minutes. In other words, many people were outside the optimal range. Not only that, we also often
apply the wrong pressure. In interviews with nurses in the Stockholm area,
only 40% applied a pressure within the optimal range And I believe this pinpoints
the value that cuffs can have: in allowing us to apply the right amount of
pressure and get better control over venous dilation. Another thing that popped up during my interviews
was the hygiene aspect. Many expressed a certain frustration
[TEXT: “Tourniquets are outright filthy”] mentioning that tourniquets might
not be especially hygienic. And I, being the nerd that I am,
wanted to
know if this was true. There have been several studies in which people
have grown bacterial cultures from tourniquets. This is a compilation of several studies.
The Y-axis is the percentage of tourniquets with a positive culture. 0% to 24% of tourniquets had MRSA on them,
depending on the study. However, these studies are from the US and the U.K.,
which have a much higher proportion of patients with resistant bacteria compared to Sweden. Unfortunately, the microbial
resistance is increasing in Sweden. This shows the annual number of cases
of multi-resistant bacteria in Sweden. And as the number of cases is increasing,
it is important to prevent the spread of resistant bacteria There are two ways to solve this: Either you can use disposable tourniquets,
which they do in the US, UK and have started to use in Denmark. Alternatively, you have
to ensure that tourniquets are regularly disinfected. Because if you regularly disinfect the tourniquets,
this isn’t a problem. So the question is: how good are we
at disinfecting our tourniquets? I sent out a survey asking that question.
Of the 240 respondents, 50% disinfected their tourniquets between each patient. 6% disinfected them several times a day and 15% didn’t know what routines they had. 8% disinfected once a day, 6% disinfected once a week, 4% disinfected once a month, 5% disinfected less than every month and 5% never cleaned their tourniquets. [laughter] Now, if you don’t have resistant bacteria,
this doesn’t matter, but if the number of resistant bacteria continues
to increase, this will become a problem. The take-home message here is that we have to
ensure that tourniquets are cleaned, or we have to start considering disposables. Tourniquets and IV access also affect
the risk of hemolyzed blood samples. And there are several ways to reduce
the risk for hemolysis. Everyone here probably knows that taking blood samples
through a syringe reduces the hemolysis risk, compared to taking samples through an IV cannula. Most of you also probably know that the
cannula’s position affects the risk of hemolysis. The studies I’ve found saw that placing a
cannula in the antecubital vein was associated with the lowest risk for hemolysis. This has
also been confirmed in a meta-analysis. Finally, tourniquet time also
affects the risk for hemolysis. One study saw 15 times increased relative risk for hemolysis
if a tourniquet was applied for more than one minute. Not only that: an Italian researcher has shown that
lab values can be affected by tourniquet time. WCC can be reduced by almost 10% and ALT can increase by nearly 20%
if a tourniquet is applied for 3 minutes or longer. And these kind of errors could, in some situations,
influence clinical decisions. These three factors reduce the relative risk
for hemolysis with 50 to 80%. So if you have high rates of hemolysis at your department,
you can try working with these three relatively simple things. Something else that people told me about was that you can either ‘milk’ a vein,
pulling with one or two hands in order to fill it, or tap the veins in order to make them stick out. So which method is better? Oddly enough, a bunch of Japanese researchers
have done a study on exactly this [laughter] They saw that 10 taps during 5 seconds caused a significant
increase in venous diameter and elevation, whereas milking the vein had almost no effect at all. So don’t milk, it’s better to tap. [laughter] Another trick is applying heat to increase
vein size. So how good is heat?
And the short answer is: very good. In one study, hot towels saved 30 seconds
for each successful IV attempt, and gave a three times greater chance of success. It can often be tricky to apply it,
but it has a good effect. Another thing we often do is ask the patient to make a fist,
in order to increase the venous diameter. Most people know this. But there is a way to increase
the venous return even more. An ultrasound study showed that stretching your
fingers can pre-load the deep veins in the hand, which in turn can increase
the venous return by 40%. Making a fist increases the risk for hyperkalemia, but can be
avoided by not using the first specimen for electrolyte measurements. So this can be worth testing: fully extending
the fingers before forming a fist. The last trick is something I’ve seen both
in my resus room and in an article. Two British surgeons did this with 22 patients
who presented with hypovolemic shock, when they couldn’t place a
normal intravenous cannula. Using this method they managed to
place an IV in 70% of the cases. The other patients were so critically ill
that they either passed away in the resus room or had a central line placed. So, imagine now that you
are back at your department and you get a patient that is critically ill and you have to gain intravenous access. It’s difficult, when you look you don’t see any veins. Also, the patient is inebriated and annoying you [laughter] While he babbles on about his studies
about IV access you get a brilliant idea. You place a tiny catheter on
the back of his hand. You apply an optimal pressure (60-80mmHg)
with a cuff on his upper arm. You then flush in 100ml of Ringer’s
lactate (Hartmanns’) as fast as possible. The guy there in the mirror, he had no idea what we were doing
when we took these photos. [laughter] He was a bit worried at first. After 100ml you look at the antecubital vein and you are very pleased when you see
that the previously invisible vein now has become more visible and
suddenly it’s alot easier to cannulate the vein. You place a larger catheter, get a flashback and presto, after some fluid resuscitation
your patient is feeling a lot better [laughter] So this method consists of placing a small distal cannula,
applying a tourniquet above the elbow, rapidly infusing fluid and then placing
a larger bore cannula proximally. It’s simple – and may be
worth trying out. Now I’ve talked about lots of things.
So if you forget everything else I’ve said just try to remember my next slide. One: Apply 60-80 mmHg when using a cuff
in order to achieve maximal venous dilation. Two: Wait 30 seconds, for the initial fast dilation,
but don’t wait longer than 60 seconds, as very little dilation happens after that
and the risk for hemolysis increases significantly. Three: Ask the patient to stretch out their hand and then make a fist,
in order to maximize the venous return. Four: Tap veins, don’t milk them. And then the other tricks: Use heat: it’s effective. If your patient doesn’t have any visible veins,
try the distal placement-method. If you can, place cannulas in the antecubital fossa
to reduce the risk of hemolysis. And four: Remember to clean the tourniquets regularly or use disposables. I hope some of this was new for you and I hope this helps you in the future
when you place cannulas and take bloods. Thank you!

Intravenösa stick: lyckas oftare!
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5 thoughts on “Intravenösa stick: lyckas oftare!

  • August 11, 2016 at 1:12 pm

    många läkare tar in blåbär ( helt ny kläckta sköterskor ) som inte kan nåt , efter 6 stick tar dom in en som är van

  • January 28, 2018 at 2:23 am

    läste nånstans att genom att knyta handen flertal gånger så kan man få missvisande prov och därför ska man inte göra så (kanske va vid nåt specifikt prov, får kolla upp det)

  • April 12, 2019 at 7:16 pm

    5:23 V. basilica
    heter den, inte V. basilaris. Annars väldigt intressant video.

  • August 14, 2019 at 7:57 am

    Jag undrar om patientens egna blodtryck påverkar hur mycket ökar ven diameter. Jag menar, kan det vara så att patienten med låg blodtryck kräver mindre pumping (t.ex upp till 30-40 mmHg) och patienten med normal eller hög blodtryck kräver mer (60-80 mmHg)?

  • September 5, 2019 at 4:56 pm

    Gammal video men att slå och knyta näven vid intravenösa instick menar du enbart vid pvk eller insättning av andra infarter? Eller menade du verkligen att ta venprover också? För de ger hemolys.. Annars intressant video.


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