Things We Say We Love But Never Do

We haven’t had that many chances to chat about something that really matters – analgesia. Here’s a post on things to do with needles by Andrew Weatherall. No acupuncture involved. 

I like drugs. I like the ones that make people drift into their own special ether world. I like the ways they bend light right or left. I like the ones that make vessels open, myocytes contract and gates stay open.

I particularly like the ones that find ways to interrupt pain pathways. Whether they antagonise or agonise (not the best derivation of that word, granted) I am a fan of most of them. This is at least in part because so much of the time we could do better with analgesia. For all the techniques at our disposal and all the agents we have, most often the literature I read on the actual delivery of pain relief would be marked with a “Could do better”.

Despite my broad ranging endorsement of pharmacological agents, when it comes to analgesia, I actually think the best option is sometimes the one that lets you use less drugs.

Which is where regional analgesic techniques really stand out from the bunch.

Providing Clarity

I should really specify a bit. Not all regional techniques seem apt for the prehospital or retrieval environment. For starters I really mean peripheral nerve blockade because the neuraxis just isn’t a place for  a needle in the great outdoors.

And not all techniques are quick enough to make the administration feasible, particularly once you consider the positioning and preparation required.

If there is one block that should be right at the top of everyone’s list though it is the fascia iliaca block to make mute a firing femoral nerve.

Of all the blocks I can think of it is the one that should be a ready-grab technique for most prehospital providers. It is quick to perform. It is reliably effective. It takes away big pain. And I’ve heard people mention it as a great technique lots of times in the cosy space of bases in all sorts of spots.

Yet, whichever way I cut my Medline searches, I get < 50 entries in the literature for prehospital care and fascia iliaca block. And when I mention I’ve used it, I sometimes draw quizzical looks. As if I’d suggested a pot of green tea to the kids at a birthday party.

Yet a well performed peripheral nerve block can mean less of all those other drugs we use for analgesia (particularly the opioids or ketamine) and those agents can have their own issues on occasion.

It tends to provide a better quality of analgesia, along with a patient who has an entirely unclouded sensorium. That super lucid patient can now become a really crucial agent in clinical assessment. At the same time they can be more aware of what’s going on without the distress of pain. I’m inclined to think that a patient who can be reassured and coached effectively through each step probably has a better journey in the long run than the one dozing in and out a bit. I’ve seen patients with both femurs smashed up cracking jokes in the emergency department with their doctors and nurses thanks to functioning nerve blocks.

So is the issue that the technique seems too forbidding? That hardly seems possible.

The Nuts and Bolts

The fascia iliaca technique was first described in the literature by Bernard Dalens, a paediatric anaesthetist. He and his colleagues had gone back to the anatomical drawing board in search of a better femoral nerve block than the ‘3-in-1’ technique. It arose from paeds anaesthesia for a pretty good reason – Dalens was after a block that would work in patients who couldn’t give you good feedback about experiencing paraesthesia, or for whom rationalising the sensation of nerve stimulation might be a bit much.

It’s a while back that this work appeared too – 1989. At the start of 1989, Milli Vanilli were still thought to be a legitimate music act and Rain Man won big at the Oscars. This is not a new technique.

In a comprehensive description of the anatomy involved (complete with radiographic demonstration of local anaesthetic spread) Dalens and crew also report success compared to the ‘3-in-1’ technique – 55 of 59 patients with a successful block of all the nerves they were aiming for (vs only 11 of 51 having block of all the nerve branches in the ‘3-in-1’ group).

They also reported higher first time success rates and less motor blockade. Sounds perfect.

It also just seems more sensible than looking for the femoral nerve. Why approach the nerve with a needle when you can produce the same block with the needle away from the nerve? Why be any closer to the vascular bundle than you need to be? I can’t figure out why you’d bother.

So what are the key points in the technique? (I start with an assumption that as much monitoring as possible is on the patient.)

1. Define the spot for the ‘X’ that marks the spot.

Join the anterior superior iliac spine and the pubic symphysis (draw a line if necessary). Divide it into 3 parts. The mark for where the outer third starts is your staging point. Now drop down a couple of centimetres. There’s your ‘X’. Want a double check? Feel for the femoral pulse. You should be at least a couple of centimetres closer to the edge of your (probably imaginary) bed.

2. Prepare the skin

You still have to be clean. It’s also nice to put a little bit of quick-acting local under the skin to make the rest more pleasant. So wait 1 minute.

3. Use the right needles

I think it helps to make a hole in the skin for the subsequent needle to work through. Sometimes the force required with the short bevel needle makes you really dive through the first ‘pop’ just by the effort to get through the skin. Everything is easier if that resistance at skin level is gone by using a standard needle first.

For the actual procedure, something with a short bevel. It’s the short bevel that lets you feel the two pops. The whole technique (when doing it by feel) relies on the two pops. The first is when you pop through the fascia late. The second is when you pop through fascia iliaca.

My other tips here – once the short bevel needle is through the skin, come right back to almost skin level. You don’t want any doubt as to which is the first pop. Second tip – steady pressure on the needle once you start. Steady pressure leads you to distort the fascia until you suddenly pop through. Then you rest for a second, start your steady pressure again and you’ll feel the sudden give more obviously. If you make short, sharp moves you can fool yourself into thinking you’ve had a pop.

4. Mix the drugs

This one isn’t from Bernard. For prehospital use you do want that block working quickly (that might be less relevant in theatres and maybe even ED). You also have that nagging worry about using solid doses of long-acting agents that might be a bit intractable if they find the heart and cause mischief.

There’s nothing that says you have to use the one agent. I tend to mix in some lignocaine with something longer acting in low concentrations. The longer-acting drug is worth it too – I’ve had patients with a fractured femur get all the way to their operation later in the day without any need for ongoing analgesia.

I'd choose 11 if I could.
I’d choose 11 if I could.

5. Turn up the volume

In the original paper, Dalens used 0.7 mL/kg for the under 20 kg child, working up to 15 mL for those in the 20-30 kg range, 20 mL for 30-40 kg kids, 25 mL for 40-50 kg and 27.5 mL for those over 50 kg (using 1% lignocaine with some adrenaline). The whole idea is spread through a plane, so more is better. I commonly think up to 1 mL/kg, with the local anaesthetic diluted to allow that volume. More volume guarantees spread without dropping speed of onset too much.


Things I don’t do? Well I don’t think using ultrasound adds anything in the prehospital or retrieval context. So I don’t do it. That said the description right here from NYSORA is pretty good.

I do still use it in some patients with other injuries – a block that works and takes away the pain of a femoral fracture, apart from being inherently good for the patient, will still decrease the overall need for analgesia because it’s like one big painful injury didn’t happen.

But What About the Prehospital Space

Well why wouldn’t we do it? Worried about local anaesthetic toxicity? Then use less of the drug. Worried about compartment syndrome? There’s no evidence that having a block changes how often that occurs or causes problems. What I think is pretty clear is that it’s entirely feasible for the prehospital environment.

It’s been described in the care of a 6 year old. Back in 2003 Lopez et al reported use in 27 patients prospectively and saw a big drop in pain scores by the 10 minute mark. 1 block didn’t work. A French group (well, in the abstract as my French isn’t quite that good) report   63 successful blocks in a total series of 107 (other techniques were on the table).

More recently, a group in the Netherlands looked at a process for training the local EMS-nurses in this technique. Their results? 96 of 100 patients had a perfectly working block.

So why isn’t everyone doing it? I couldn’t find good research on that. So maybe it’s just that we spend so much time talking about other options, we forget what is, at its heart,

Or maybe it’s just habit and we need to people to remember there’s nothing about being able to block rapidly firing signals along sensory nerves with drugs in the same loose family as cocaine that shouldn’t be considered sort of astonishing.

Maybe next time there’s a patient with a badly bent femur you could start with a simple question: can I block this pain?

(Pssst … you know the answer already.)


I did a second edit to add a little more description (paragraphs 2 and 3) in the “Use the Right Needle” section. I also added a paragraph to clarify why I’d choose it over the femoral nerve block just before launching into the list of technique tips. It’s the paragraph that starts with “It also just seems more sensible …”

The original Dalens paper is sort of a joy.

Here’s that letter regarding use in a 6 year old.

Here’s the Pubmed link for the Lopez paper.

Here’s the Pubmed link for the French paper.

And here’s the SJTREM paper where they trained up EMS-nurses.

Oh, and to really understand how much can be offered by good regional techniques in retrieval medicine, it’s worth looking up this account of a soldier injured in Iraq. They had most of a calf blown away. With the addition of two nerve catheters (lumbar plexus and sciatic) they had initial debridement and subsequent operations interspersed with multiple long flights to finally make it back to Washington via Germany. All with good pain relief.

The image in this piece is in the Flickr Creative Commons section and is unaltered from the image posted by amp.




Teaching an Old Dog New Tricks – Or A Visit To An Alien Planet

One of the excellent things about retrieval work is the opportunity a clinician is presented with to try new things. Dr Alan Garner reflects on his recent experiences trying out a very particular branch of retrieval medicine – neonates and paediatrics. 

I have recently had the opportunity to do some work with NETS in NSW due to some staffing issues they have had (completely outside their control). For those not familiar with NETS they are the Newborn and Paediatric Emergency Transport Service in New South Wales (NSW). They are busy too, moving about 2700 patients are year, and fielding calls and offering advice on perhaps another 1500. There are also some perceptions out there in New South Wales that NETS cases take a long time, a good part of which is spent in conference calls.

I am an old dog. It is more than 20 years since I passed my fellowship exam and I have never really had much exposure to neonates, particularly significantly prem ones. My ED practice is in a hospital with a high risk obstetric unit and NICU. These patients never come near the ED. So this has been a scary experience for me dealing with patients that might as well be aliens as they bear so little resemblance to what I know. NETS also has a few legends attached. Mostly of long phone calls and even longer jobs. I came to the job keen to see things for myself.

When they’re the scary sort of alien

Some of my colleagues from CareFlight who are also helping out on the NETS roster are paediatric anaesthetists in their non-retrieval life. The first solo NETS shift that any of us did was by one of my paed anaesthetic colleagues. She was sent to a neonate with severe meconium aspiration in a metropolitan hospital in Sydney. After intubation and ventilation on 100% O2 the baby had airway pressures in the 40s, an unmeasurable tidal volume and pre-ductal saturations of 80. I had nightmares that night wondering what I had got myself into and feeling completely out of my depth.

Despite my initial terror I still managed to front up for my first shift and discovered that my colleague’s patient was possibly the sickest NETS had moved all year. Slightly calmer now I have survived several shifts and thought it might be time to give the old dog’s perspective of the alien landscape I have found myself in.

Describing other planets

For all the adult retrievalists out there that dabble in some paediatrics i.e. people like me, let me try and explain what it is like. Imagine a service set up to do only interhospital transports of patients with respiratory failure. There would be lots of people with COPD and asthma, pneumonia and ARDS. For the first two groups you might spend hours at the scene stabilising a patient on NIV before feeling it is safe to move them.

This represents excellent care as we know that once they are intubated the mortality rises sharply. Same with the pneumonia and ARDS patients – good critical care at the referring site is what it is all about and may even include getting an ECMO team to them. There is absolutely nothing time critical about moving any of them and it would indeed be poor practice to attempt to move them too early.

Now if you have been able to imagine such a service, this is what the population that NETS transports is overwhelmingly like. There is rarely any time critical intervention waiting at the receiving hospital, and getting them stable for transport can take a very long time. Neonates with hyaline membrane disease are the absolutely classic example of the stay and play patient. Intubate them, give some surfactant then wait for it to work. This is excellent management for these patients.

And you also have to understand how physiologically brittle these little creatures are. Just give them a poke and their sats are 70% (you think I am exaggerating). You really want to be sure that you have some sort of stability before you start bouncing a patient like this around in a moving vehicle.

The smallest patient that I have moved was 950gms. The only reason that I agreed to do the move was the kid was basically OK and was being moved from a NICU associated with a paediatric hospital to one closer to the family’s home so that another baby that needed paediatric surgical input could be accommodated.

This baby was “well” with just some air running by high flow nasal prongs. However if you picked him up, he cried or you shook him about (in a moving vehicle) his sats were high 70s/low 80s. And this was a well baby by their definition. The nurse I was with did a fantastic job (thanks Charlotte!) and I did my best to not look like I was getting in the way.

Space and time

For those that think NETS take a long time then you just really don’t get the patient population they deal with. There is no urgent interventional cardiology or transport to stroke centres. There is no parallel in their alternate universe to these patients from the adult world. The closest they get is trauma patients. Trauma however is a tiny proportion of the caseload, and the trend is increasingly to non-operative management wherever possible anyway. I have been hoping to do a trauma case when I have been working for NETS as that is right in my comfort zone. However there have not been any for me to do. Rather it has been lots of prem and term babies, and infants with either respiratory issues or seizures. The one nagging question I have is how a system more used to steady movement of a patient springs into action when they really do have to push it along. A bit more time and I might get to see that too.

Not those sorts of alien but there is a link to phoning home sort of ...
Not those sorts of alien but there is a link to phoning home sort of …

Connecting Across Space

As a team member I have also had the opportunity to listen in to a lot of coordination calls. NETS coordination is a bit of a legend in NSW and rightly so. With a NETS transfer everyone at both ends (and the retrievalists in the middle) is involved in the initial conference call, and often any update calls along the way. And they can be long calls. There is a big plus though everyone knows what the plan is and they own it.

Just last week I was visiting one of the paediatric trauma hospitals in Sydney and they were lamenting that this is sometimes not the case when the adult system was moving a severely injured child, where it’s always been the case that the retrieval team takes the job and gets on with the job. That’s just how it’s been for as long as I’ve been around. They did not know what was happening or when the child would arrive. This is never the case with the NETS system. Although this theoretically is supposed to be the case in the adult world too there are lots of instances where it just does not happen unfortunately (I take as a reference point this report).

People find it easy to point out flaws with their approach, but I think the NETS coord system has several strengths:

  1. NETS encourage the concept of “there is no dumb question” for all the non-paediatric hospitals in NSW. NETS accept that they will field some silly stuff that should probably never have got to them so that they don’t miss any child who really is sick. For the low level stuff they patiently patch the caller in with the local paediatrician (sometimes in the hospital the caller is in) so that the local systems can manage the case wherever possible.
  2. An extension of this is they look for the nearest solution to the problem and don’t assume that a call equates to a request for transport. Getting the right people involved locally can often solve a problem locally. Or the closest solution for the patient might be a service somewhere else like across a state border.
  3. As they work at finding the best solution for the patient, all the players talk together to agree and own the plan. As I have already said, there is never any confusion about who is doing what on a case that NETS coordinate.
  4. The nurses who coordinate the calls at NETS are actually moving babies themselves the day before and after. They know all the logistical and clinical challenges as coordination and transport are both part of the same job. It is notable that London HEMS has a dispatch system which works because the dispatchers are paramedics who work on the helicopter as part of the same job. I don’t think this a coincidence.

Retrieving Little Aliens Produces Other Big Challenges

If NETS has a weakness compared with the adult services it is perhaps the fact that not many of their cases are done by specialists except when they are coaching new registrars. Particularly on the neonatal front some of the babies are fiendishly difficult to stabilise adequately for transport (like the first case done by my poor anaesthetic colleague mentioned above). They really need a consultant neonatologist for these cases as they seriously stretch the capabilities of both the humans and machines (see below) involved in caring for them. Perhaps an unexpected bonus of the recent challenges in staffing will be a few extra specialists in the shift mix seeing as the whole team benefits from their experience when they’re online.

Another issue is the equipment. Across all age groups NETS currently have four different ventilators which is a bit of a nightmare for new registrars coming into their system (although the skill of the nurses is a big mitigator here). Over the years as they have added new lines to the roster to keep up with increasing demand, they have added just enough equipment to keep up without retiring any of the old stuff. Some of the ventilators date from the 1980s. Although they still work, you would not find a machine of that vintage operating in an intensive care unit anywhere in NSW.

Infants are a particular problem. They have some Oxylog 3000 +s but they just will not ventilate a child with an ETT less than 4.5mm diameter and they struggle with bigger kids too if they have any lung pathology. There are newer turbine transport ventilators out there that can deliver a 2ml tidal volume and also ventilate a 100kg 15 year old. One ventilator could do the lot which would significantly decrease the training burden and hence increase patient safety too.

It will take a cash injection to fix this I suspect and it is not just buying the ventilators. The neonatal systems and paediatric bridges will need modification to mount the ventilators and in the aeromedical environment that means engineering certifications etc. etc. No cheap fix here. I understand this is currently being investigated but it can’t come soon enough.

And a final comment on the staff. As I am doctor, I have not had the chance to work directly with many of the NETS doctors as the standard team is doctor/nurse. I have now worked with a number of the nurses though and have been really impressed with their professionalism. It should be obvious from the caseload that I have described above that the little details really matter with these patients.

Like all good critical care nurses the NETS nurses have just the right level of OCD to be obsessive about the stuff that matters, but not quite enough to drive you nuts. I have been impressed with the risk management approach and planning, like discussing best and worst case scenarios with appropriate plans for each on the way to every case.

For me this has been a real learning experience. I am still way out of my comfort zone but hopefully there is still room for a new trick or two from the old dog.

Notes and References:

Here’s that CEC report on Retrieval and Interhospital Transfer again.

The image here is from the Flickr Creative Commons area (unaltered) and was posted originally by JD Hancock.

In the meantime, Alan can’t be the only one who has found something that really challenged them recently. Any stories to share? There are comments for that.