Definition – To suss: to look into something deeper, and acquire more information; or to solve a problem or puzzle using ingenuity.
This is a concept I have been thinking up for a while. And it turns out others have also been to the same place. Dr James Rippey (Ultrasound Village) and colleagues published this paper in 2009 that “brainstormed” all the possible uses of bedside US in trauma patients.
So what the heck is a “SUSS IT” – and why is it any different to what you do now? It stands for Secondary UltraSonographic Survey In Trauma. If nothing else it has a cool acronym! It is not a single scan, or protocol – it is more like a shopping list of all the scans that just might come in handy when dealing with a trauma.
I reckon there is are two types of US-users out there. There are some true diagnosticians who do scans to a standard that allows them to produce a reportable finding. Then there are the rest of us: ED docs with a probe and a prayer… we have a varying degree of experience and know our limitations. I am certainly in the second category – as are most ED docs I know. For me bedside US is basically an extension of my clinical examination. Often it provides a lot more information which allows me to change my management. My scan will never be comparable to a CT in terms of sensitivity, but it is a whole lot better than me using my eyes, ears and fingers only. Some parts of the ‘SUSS IT’ are clearly validated, have a basis in evidence and are used extensively eg. FAST, lung scans.
Well – same as you currently do a primary and secondary survey, but you use your US probe to sharpen your diagnostic screen. We know that a lot of the clinical examination that we do is insensitive and unlikely to change management (Chris Nickson posted a great example of the inadequacy of rectal examination in trauma this week. Check out LITFL “Adding insult to injury”
Sure, if you are going to do a panCT you probably will get a lot of the info from that. So why bother?
– Avoid radiation in the lesser trauma patient
– If you work in a CT-free hospital, like many in rural Australia
– If you are in a completely Xray free place – as in many places, at night, or on weekends
– If the patient is too sick to go to CT
– To diagnose those minor injuries that go along with major injuries, without having to go back to radiology dept.
– To get info early in the resus
– The haemodynamic and functional assessments eg. ECHO, IVC, ETTube / line placement – you need this data now – not after the CT.
– Because it is more useful than doing nothing whilst waiting for the flight team.
- Assessing for intubation difficulty by US might be more accurate than clinical asseesment – small pilot study, suggests it is more accurate than our usual techniques, and can be done in an unconscious / supine patient.
- Pre-induction marking of the neck for potential surgical airway has been widely used.
- US-guided surgical cricothyroidotomy – it might work – see this from the US podcast boys, paper pending – watch this space
- Verification of ETT placement and bilateral lung ventilation has been shown to be fast and accurate by Pfieffer et al
There are a number of applications for US in diagnosing and assessing the circulatory status of trauma patients. Also good for access in the tough cases
- IVC diameter / change with respiration – has been used a lot to assess for hypovolemia / fluid responsiveness. A few studies show it can show subtle loss AJEM published this. Emcrit has a video showing you how to do it here (IVC collapse). Its not too hard.
- A focused ECHO looking at the LV for hyperdynamic motion in the context of trauma blood loss is good evidence you need to give red stuff! Another great clip from Ultrasound Village.
- Arterial line placement – sure we can do it without an US, but sometimes in the truly shut-down patient it can be tough. I found this study in Acad. Emerg. Med 2008 which shows it might be quicker, and require less stabs to get it in with the US probe in the other hand.
- IV access – surely the biggest IVC you can get in the biggest vein is a good thing – but in the world where obese people with deep veins can make you earn your keep – I think having the probe nearby just might come in handy.
- CVC placement. For me I always go for an IJ line in trauma if possible. Check out Sonoguide’s guide to all things US-guided venous access here
Disability / Neuro
This is maybe a bit more controversial. The use of US measurement of optic nerve sheath diameter (ONSD) to detect raised intracranial pressure has been studied by a few groups in the last 5 years. Mostly small studies, comparing to CT changes or the readings from an invasive pressure monitor. Certainly the numbers they come up with look good in terms of sensitivity. I did a review on this last year (Raised ICP – Can we pick it?)
. Not sure if this is ready for “prime time” but it has to be worth a look (it is quick and easy) and add the data to your overall ‘gestalt’ – maybe you will do your RSI a bit differently? Get that CT earlier?
What I want to see is a basic statistical study that looks at 1000+ ONSDs and established a normal curve – there seems to be a wide range of “cut offs” used in the papers I am reading – so I want to know – when is it really 2+ SD outside the norm? Any takers? Come on – US Village, US Podcast….
When it comes to eye trauma – US is the only way to fly. You can see it all, even if the brow injury has swollen the lids tight shut! Lens dislocation, globe rupture, retinal detachment, IO foreign body, bleeds – you can see them all. Much better than the ophthalmoscope in a patient who cannot follow intructions etc. Check out Sonoguide’s Ocular section fo
r some good pics.
Picking a hyphema might require you to look with your own eyes – but the rest US is great for!
Already covered most chest / lung injuries under “Breathing” above – but not the heart injury.
Traumatic pericardial effusion / tamponade – Beck’s triad [low BP, muffled heart sounds and distended neck veins] is the teaching, but it sucks in reality. So use US / ECHO – as shown at Ultrasound Village here
Aortic injury – probably outside the scope of the average ED US user.
Pulmonary contusion – Toby Thomas suggested this link – Chest 2006
Soldati e al suggest US is as good as Ct for contusion.
- FAST scans are well studied and used all over the planet. There are well defined clinical algorithms for the use of FAST scans such as this one from the Scand. J of Trauma, Resus and E Med 2009. I think most of us know and can use the FAST – so I will say no more about it here.
- Pregnancy assessment – in trauma there are a few questions you need to ask:
- Is this woman pregnant?
- Is the fetus alive?
- What is the gestation? ie. are we past the point of viability should delivery occur?
- Are there any obvious injuries. NB: using US to exclude an abruption is not a good idea, proven to be an insensitive exam (~50%).
Whenever I do a secondary survey I “spring the pelvis” and wonder – what is the sensitivity of this? My guess not that great, and we know that PR exam is terrible for detecting pelvic injury. I recently saw this paper (thanks Cliff Reid @ resus.me) from Journ of EM 2011
, which suggests the simple act of scanning down onto the pubic symphysis and measuring the “gap” is prety good for detecting open-book fractures [for me this is a great example of a quick US technique which allows me to make my exam sensitive and objective – thus allowing earlier intervention – get that binder on, arrange transfer to somewhere they can deal with a pelvic injury. ]
So what about other pelvic fractures? well, it is a big bone that you can see on US – I reckon I could pick an iliac wing fracture pretty easily
- Long bone fractures are usually clinically obvious, but sometimes they can be subtle – especially in the unconscious patient. It can be easy to miss a radius or fibula fracture when you are busy fixing the chest or head injury.
- I have often been in the scenario where I finally get around to looking at the littler bones after all the resus is done and find something minor. Usually we just clean, plaster and tie it up for transit – but why not use the probe to confirm the injury – and avoid another trip to Xray with the ventilator? At least you can warn the receiving team about it – embarrassing to diagnose it on day 3 when the patient wakes up !
- Is there a fractured bone in that messy deep wound? Have a look – might need a proper washout sooner rather than later…
- Need to find some shrapnel, Us is good for this – it would be remiss to not have a link to an article from Dr Blaivas (Journ of US in Med)- so check out this one that looked at gunshot wounds in limbs. Blaivas is the guru of US in Emergency medicine in case you need to look something up.
I hope I have convinced you of the following:
- Ultrasound is a useful extension to clinical examination. I am not suggesting that you use US in place of X-ray or CT if appropriate – I am saying you can use US as a way of sharpening the clinical exam and finding the pathology etc quicker.
- We know that our clinical skills are just not that great for much of what we need to achieve early in managing trauma
- Despite working in a small hospital – you can get a lot of information quickly using US techniques in trauma cases.
- If you are in the field or on a plane – then the SUSS IT is ideal. The evidence from disaster scenes shows it does make a difference to disposition and other decisions in the early stages of management.
- The SUSS IT is a smorgasbord of techniques that you can use as required to get information and modify your management in real-time.
- Most of these ‘scans’ take seconds to do – in a busy resus, they may be seconds well spent if you have the resources to do it…
I hope this gives you a platform to explore the utility of US in trauma. This is a rapidly expanding field of evidence, and I know I have missed some great US-tricks. So please let me know – are there any more morsels we can add to the smorgasbord?
I hope to make this a “Clinical Resource” and update it as new evidence comes to light.
Happy scanning – Casey