Tricky IV access


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Author: Charlotte Davies, Dan Paschoud / Editor: Liz Herrieven / Codes: / Published: 14/01/2020

The next patient to be seen is a 45-year-old IVDU with a possible pulmonary embolism. They’re difficult to bleed, so the Nurses and Techs have not obtained bloods, or access. You realise you need a CT scan, so access is down to you… …

Tricky IV access. We all see it all the time. Some people are great and “lucky”, and some people always struggle. I struggled to become confident with IV access. Initially, I didn’t like “hurting” people by sticking a needle in them – and then I realised the best way of not hurting them was to do it well. I was most put out when as an FY1 struggling to gain access, the Urology Consultant I was working with put a grey in, with no sweat. What’s the secret? Here’s a few tips and tricks to get you going.

IV isn’t always the only option. IV fluid doesn’t clear alcohol any quicker, yet we still seem to try it. An oral fluid challenge may be as effective as an IV challenge, depending on how unwell the patient is. There’s thousands of papers citing oral antibiotics are as good as IV for cellulitis. Macrolides like clarithromycin have good oral effectiveness – as good as IV – and we know IV paracetamol doesn’t work any better than oral (it really doesn’t!). Furosemide works in about an hour if you give it orally and peaks in about 30minutes IV (it used to say that in the BNF but now I can’t find it). IV metoprolol may work quicker than oral bisoprolol – but bisoprolol is preferred by most as it lasts longer. There are plenty of options for administrating analgesia that aren’t IV – intranasal, sub-cut, intra-muscular or even oral! We really try not to give IV analgesia to our sickle cell patients – not because we’re mean, but because repeated IV cannulations make cannulation even trickier when it is needed.

We’re really good at (mostly) not cannulating children unless we need to. Before you cannulate an adult, ask yourself if you’d cannulate them if they were a child. If not…why are you cannulating them as an adult?

I asked on Twitter what everyones tips were for gaining access. For the responses, have a look at this fabulous twitter thread.

The responses broadly fall into a few groups:

a) Self Positioning and Preparation

You need to get yourself into a cannula zen zone. Go in with a positive can do attitude and convince the patient that you are the person for this job! Whilst you’re generally talking to the patient – and relaxing them – ask them what works.

Get comfortable. For some people that’s sitting, kneeling, crouching – what ever works for you. But take time to get it right.

b) Patient Positioning and Preparation

Make sure the patient is comfortable. If they need a pre-cannula wee, and it’s safe to do so, let them wee! Talk to them, which will help them relax. Give them a positive suggestion that their veins are nice and juicy with good blood flowing. Then get the patient’s arm warm. Lots of techniques have been suggested – warm water in gloves, warm towels, hot water bottles, normal saline from the fluid warmer etc.
Once your patient is comfortable make sure that you use gravity to help.
If they’re really oedamatous, you may need to massage oedema gently out to give you the best shot at the vein.

In children, the patient preparation is so so so so so so very important! Topical anaesthetic gel (ametop, EMLA etc.) is a must unless there’s a good reason not to. Even neonates feel pain – sucrose drops are often used in some departments, although not analgesic and probably more of a distraction. Older children also need to be distracted. A play therapist will be invaluable here. Hypnosis can also be used – if in doubt, don’t forget the bubbles! Positioning is uber important. There’s some more resources available here.

c) Equipment Preparation

There is no question that you need to get your equipment ready. Make sure you’ve got it all ready and open – nothing frightens a patient more than hearing rustling and people popping out to get more stuff mid-procedure! Think about whether you want a small 22G, as a blue in is better than a grey out, or whether you need a grey at all costs. If you’re using a small cannula in frail patients, curving the needle slightly can help make sure you don’t go too deep.

Make sure you have a big enough cannula:

but do listen to this RCEM podcast before choosing your cannula size for a CTPA.

Choose your tourniquet really carefully – you need a good one. By a good tourniquet we don’t mean a rubber glove tied round the patient’s arm. Ideally an old fashioned re-usable tourniquet is preferable. A BP cuff can be a useful tourniquet as can an arm squeeze. But make sure the tourniquet doesn’t obliterate the pulse! Two tourniquets may also be useful.

Consider pre-filling the cannula with normal saline, to get much quicker flash back especially if the cannula is small.

d) Look for different veins

Firstly, there’s some evidence to suggest using the ipsilateral arm of breast cancer is OK (also here).

Secondly, the basilic vein in the medial upper arm is often missed. Think about the external jugular in adults or older children and the lateral border of the foot in babies. There’s often a “cheeky vein around the thenar eminence”. Remember to look under the watch and the chest wall may also be appropriate.


You can also consider using the external jugular – described here by ALIEM.

Ultrasound is great when cannulation is difficult. I use it nearer a last resort as it doesn’t fit into the bay, is never charged and…isn’t good when the veins have collapsed. But, it’s undeniably a useful skill. For more information, look at our learning module – remember not to push too hard and to have a long cannula (also reviewed here). This technique is probably not great in children – ultrasound makes cannulation harder!

Cannulae being too short was the topic of a recent St Emlyns journal club review – check out the replies to the tweet for some more fabulous pictures.

a) Red Light is supposed to be as good as a cold light. However, there has been at least one incident of a red bike light causing burns to a neonate so we would advise against using this technique.

A caveat toys arent designed to be used as medical equipment, and may not have undergone rigorous medical testing.

b) AccuVein

Some people love this, some people hate it. Learn how to use it here.

c) Cold Light

by Dan Paschoud

We’ve all been (or will be) there; a patient in cardiac arrest.

We need access…

We all have our tricks and tips that we’ve picked up over the years – a favoured tourniquet, a larger vein often overlooked by most, and fortunately the now rarely seen repeated slapping of an area in some vein (!) attempt to bring that hidden vessel to prominence.

We know that as cardiac output diminishes, peripheral vascular shutdown occurs.
So; as the minutes tick by the task of gaining an intravenous route for medications and fluids will become tougher. There are central lines of course, but these take time, finesse and appropriate preparation.

Intraosseous access is a technique that most are aware of, however there still appears to be a reluctance to use it, or reliance on the traditional vascular access that we feel more familiar with; to ‘have a go, and then IO’, but why is IO still considered plan B or C?

Clinicians I have taught often see this as tough, but when you think about it; bones are far more palpable than most vessels we have ever inserted a cannula into. In the in-hospital setting there are two main sites that we use for intraosseous access on an adult; the proximal tibia and the humeral head. Whilst both sites will provide vital access for these patients, I often see clinicians (in both practice and teaching) favour the proximal tibia. The common rationale tends to be that landmarking is easier and the lower limb area tends to be ‘less busy’ in cardiac arrest situations.

I cannot refute either of these points, but what I will say is that comparable to the humeral site the proximal tibia offers inferior flow rates and medications administered via the humeral site can take less than 3 seconds to reach the heart. When you consider the critical situations where we would typically consider IO access these two factors should bare consideration.

So, how do we overcome these two hurdles?

It’s all about the positioning of both the patient and the practitioner.

Previously I have been taught this position for landmarking of the insertion site

In the context of a cardiac arrest; you can probably imagine how challenging this would be. Stabilising the limb for landmarking and insertion in this position could also obstruct CPR provision and is difficult to maintain with CPR ongoing.
I recommend trying this instead; adducting and internally rotating the limb…

This position not only increases the prominence of the humeral head; it is stable and will not Impact CPR provision.

So, here is the arrest scene.

It’s the same question I have been asking myself since I was an angsty teenager:
Where do I fit in?

As you can see from the diagram, this inverse approach leaves plenty of room at both airway and the chest.

In an ideal clinical setting, you would have a CPR provider, and someone ready to take over CPR on the alternate side optimizing changeover, minimizing interruptions in CPR.

As with all cardiac arrests the key here is COMMUNICATION.
If situationally you have one side of the patient being used for CPR due to environment or because the team is using a step, then just ask someone to join you in the CPR 2 position.

Once you have picked the appropriate humeral head to approach (with consideration to contra-indications and relative environment) wait or ask for CPR relief on the side opposite yourself. There is a large sharp driven by power, so the team should be aware of what you are doing.

Now ask CPR 2 to help you position the patient for landmarking and insertion; stabilising the limb by the forearm in the position from image 2.

To landmark I now use an ‘inverted’ approach relative to the patient position, running my thumbs up towards me along the humerus until I feel the ‘golf-ball-on-a-tee’ denoting the surgical neck. I can now locate from this the appropriate humeral head site and insert my IO device into a site that will deliver optimal flow rates for vital infusions.

Full credit to the fantastic educators from the Teleflex procedural lab course that helped to me to develop competency and confidence in this important skill, and gave me the tips I have discussed in this blog.

How to Insert an IO:

  • Check there’s no contraindications
  • Clean the site
  • Find your landmarks (humerus and tibia)
  • Collect your equipment and size your needle
  • Push down through the skin until you feel bone
  • Drill until you feel a give
  • Remove the needle, leaving the stylet
  • Aspirate
  • Attach the dressing, then connect a flushed giving set
  • Consider initial flush with lignocaine – check trust protocol.

Teleflex has a wide range of educational resources free to access, and free to help teach.

This used to be taught as part of ATLS, but other techniques have now taken over. I’ve included it here incase you’re desperate. And maybe some hospitals still use it?

We hope you liked this crowd-sourced style of #RCEMBlog. We’re hoping to compile a few more blogs like this and we’re thinking one every two to three months. We’ve created our shortlist – please vote for your favourites on the google form/survey monkey, and we’ll compile and release the most popular first. We can’t do this without your help though. Keep an eye out on #RCEMBlogs for the upcoming topic, and send us your tips and hints for how to manage that procedure. Please complete our survey here, or get in touch.

Related Posts & References

Twitter thread on cannulation from docbenh.


  1. Montez, D. F., Puga, T., Miller, L., Saussy, J., Davlantes, C., Kim, S., & Philbeck, T. (2015). 133 Intraosseous Infusions from the Proximal Humerus Reach the Heart in Less Than 3 Seconds in Human Volunteers. Annals of Emergency Medicine, 66(4), S47.
  2. Stein;, J. P. M. D. S. F. B. H. C. C. M. R. T. (2015). Intraosseous infusion rates under high pressure: A cadaveric comparison of anatomic sites. Journal of Trauma and Acute Care Surgery, 78(2), 295299.


  1. Sardar Nouman Akmal says:

    This Tricky IV access topic from RCEM Learning is quite informative and will be much helpful for me while working in Emergency Department.

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