A few weeks ago I was honoured to be on faculty for a fantastic course run in Ireland for the first time, resuscitate.ie
This superb initiative was organised by EM SpR Shane Broderick and Jason van der Velde and was billed as an Emergency Surgical Skills trauma course. Critical life-saving skills were taught during this 2-day resuscitation extravaganza using fresh unembalmed human cadavers. If you have dipped your toes in the #FOAMed world you would recognise some familiar international faces on the faculty such as Mike Abernathy, MJ Slabbert, Ann Weaver and Mark Forrest as well as the best of Irish talent
Earlier in the year, I attended the Coventry Regional Anaesthesia Workshop and Lectures in the UK. Ultrasound guided nerve blocks (USGNB) are one of the few POCUS applications that can be practised using cadavers. We have really encouraged the use of fascia iliaca compartment blocks for all femoral neck fractures in the Mater Hospital Emergency Department and have also been using other novel ultrasound guided regional anaesthetic techniques for common painful conditions (serratus anterior plane block)
Before we dive into the blocks, there are a few things to consider if you are keen to start using USGNB in your department
Should we use US guided blocks in ED?
Yes – this one is a no brainer! Here’s why:
- We manage acute pain in ED and US guided blocks are part of a multimodal approach to pain management. The more options available, the better for your patients
- The explosion of POCUS in ED has democratized the use of regional anaesthetic techniques. The ability to localise a fascial plane using US, introduce a needle in real time under direct sonographic vision to deposit local anaesthestic agent (remote from the nerve tissue) makes these procedures safe and feasible in the ED. The idea involves the use of a large volume (20 – 40ml) of a dilute (0.25% levobupivacaine) agent to bathe the nerve and achieve analgesia safely. For a plane block, ACEP recommendeds that your patient has cardiac monitoring during the procedure and for 15 minutes afterwards. This is in contrast to the recent RCEM recommendation stating that vital signs should be recorded for up to 30 minutes following the procedure
- US guided blocks may be the only available option for some patients in which procedural sedation is contraindicated. Using US blocks means that we can avoid opioids with the unwanted side effect profile. The most obvious example that comes to mind is serratus anterior plane block as an alternative to opioid use for rib fracture analgesia in a population that is already at risk of respiratory compromise
If that’s the case then why are we not using nerve blocks more often in the ED?
One of the major hold ups when getting started is the lack of a single location for all your supplies – you need to get one piece of kit from the store room and another piece from a resus press. How many times have you walked around the ED assembling your kit to find that the US machine is already in use somewhere else?!
To make life easier, we recently introduced a block trolley to our ED – it has all the necessary supplies in a single location ready for use. I borrowed this concept from our anaesthetic colleagues in Galway hospital where I spent a few weeks in their well established ‘block bay’. For our set up, we prefer the Pajunk pack as it has all the necessary pieces of kit in a single easy- to-use pack – a syringe, block needle, sterile probe cover and tubing. See this fantastic ACEPNow paper by Arun Nagev on this topic
Practice point : for large volume blocks (> 10ml) it is recommended to use a 2-person operator technique while a single operator is usually adequate for lower volume blocks (< 10ml)
To get started, you could choose a specific painful condition and build your nerve block trolley around this for example FICB for hip fracture. Once this pathway is established, you can then use your trolley for other similar conditions (SAPB for rib fractures)
The set up
The set up is all important as you approach your patient for a nerve block
- Orientate the needle, transducer and the US screen in a direct line of vision so that the operator does not move her/ his head during the procedure. This may mean that you place the screen on the contralateral side of the bed from the operator
- The transducer of choice is the linear transducer – this is a high frequency transducer that will give you the highest resolution screen images necessary for visualising superficial nerve structures
- When I insert a needle into my patient, I am extremely careful that I visualise the needle tip at all times – this is done by using a in-plane approach. This is a video of a piece of tofu that we use for US teaching – you can see the needle shaft and tip in plane at all times as it approaches the target (credit to Jenn Cotton for introducing the tactile tofu task trainer)
Using the in plane approach will help avoid complications such as inadvertant nerve or vascualr injury
Practice point : use a small volume of saline in a syringe to hydrodissect the tissue plane before you deposit local anaesthetic – this will allow you to maximise the volume of LA that is delivered to the plane
NOW FOR THE BLOCKS….
It is difficult to describe how to do a block in a blog but I think that there are 2 core elements involved when teaching this skill
- localising the interfascial plane or the peripheral nerve
- needle guidance skills
Both of these are important to master and are probably best considered separately as a new user
Serratus anterior plane block
This is a relatively new block and was first described in 2013 by Blanco – the co-author on this paper is John McDonnell, consultant anaesthetist in Galway University Hospital. Serratus anterior deposits local anaesthetic solution over the top of the serratus anterior muscle as it wraps over the top of the rib. It works by blocking the intercostal nerves as the emerge through intercostal muscle. The solution is then dispersed by the patient’s respiratory movement to effect multilevel analgesia
These videos show how this block is done – much better than I could describe it here!
Erector spinae plane block is a new block that provides better analgesia for lateral and posterior rib fractures. Similar to SAPB, this is a plane block but the insertion site is more posterior. Read this paper to learn more about it
Fascia iliaca compartment block
Fascia iliaca compartment block (FICB) is our preferred plane block for neck of femur fractures. The interfascial plane containing the femoral nerve is infiltrated just medial to and inferior to the anterior superior iliac spine, using an infra-inguinal approach
For a fantastic description of how this block is performed, check out Jacob Avila’s 5minsono website
No blog post would be complete without a list of resources by experts that produce high quality educational resources. Here are my top recommendations
5minsono – everything on this site is amazing
highlandultrasound – my go to site for block related material
Needle guidance tips from pocustoronto.com
Mike Stone on Vimeo – everything!
Finally, here’s a super infographic compiled by Shane that you can use to access all the learning materials from Resuscitate.ie