The POP, the Chief, his risk assessment and her thromboprophylaxis

So, we’ve already talked about this. But changing times call for changing posts. And we want to know what you think…

A 30 year old comes in 10 days after being put in an equinus POP for an Achilles rupture. His leg hurts more now than ever. You split the pop – swollen to mid thigh. Whole leg CUS shows a popliteal thrombus. Oh dear. 3 months of warfarin for you, my boy.

The next one out of the box is a 30 year old woman with a similar injury. She has no risk factors for VTE. You ask for an equinus cast. She is half way out the door.  But then you stop to think. And you scratch your chin. And you ponder…

Thromoboprophylaxis for ambulatory limb trauma is not a new idea. The French and Germans have been interested in this for ages. There are individual centres in the UK that have tried to tackle the problem head on (and also provide nice slides to say how – good FOAMed even prior to its inception!).  Both NICE and ACCP recognise the issue, but fall short of digging into it based on potential issues with the evidence (see below for the NICE effort). Some people even think it’s not a problem. But we keep seeing harsh lessons in both the media and medical literature. So we need to ask ourselves – how can we manage this issue in an evidence based way?

There is actually a lot of evidence for perusal, including several systematic reviews and a well conducted meta-analysis. As well as this, there are loads of studies from different countries looking at incidence and reiterating the issue: a certain proportion of ambulatory trauma patients discharged in POPs, wherever they are, whoever they are and whatever their injury, will develop VTE. As a global specialty, we should be on top of this.

One of the difficulties with the evidence is trying to segregate the data that applies directly to our patients from the mass of heterogeneous papers looking at post-op patients. I would suggest the evidence is already there to support extended prophylaxis in the majority of patients who have had orthopaedic surgery. What I want to know is: does the plaster on its own warrant prophylaxis?

I think it does. Along with some Virchester colleagues I have recently had the pleasure of reviewing all the evidence and attempting to provide a pragmatic appraisal and translate this into a workable guideline. The result is a 2 page clinical decision support tool (And a lot of additional light reading) recently endorsed  by the UK College of Emergency Medicine – it is front page news at the moment but will be easily found in the guidelines section when the buzz dies down.

Some people have worried about potential morbidity from use of prophylactic anticoagulation. I think the evidence suggests that low molecular weight heparin (LMWH) in prophylactic dose is actually fairly harmless to the majority of these punters, provided you use it properly. And I think any DVT (including distal/calf) is something to be avoided. The risks of untreated thrombi include propagation, embolization, post thrombotic syndrome, symptomatic progression and impaired fracture healing. I’ll take a few weeks of LMWH over that lot any day thank you very much.

Does everyone need it? – probably not. There is good evidence to suggest that low risk punters (those with minor injuries/no fracture/no POP/no additional risks for VTE) will probably have a low chance of subsequent VTE.  But the main thing we wanted to try and change with this guideline is the thought process. Think #/POP?  – think risk assessment for VTE. You’ll be amazed how many 25 year old women say yes to the COCP/Smoking/FH/Long haul travel next week if you take the time to ask them about it properly.

Where next? I know the Dutch are currently in the throes of evaluating Nadroparin in a large sample size for this very indication. I know people demand and expect a higher level of evidence prior to establishing as routine what may involve a significant cost and a degree (likely very small) of morbidity. I personally also think the new oral anticoagulants (NOACs) might have a role to play here. Anyone keen for an international multicentre trial should get in touch – we could knock that out in no time with the right support and funding.

But until this evidence comes, I think there is enough overall to warrant strong consideration on an individual basis. I personally don’t need to see a flawless systematic review to make me think a treatment may benefit my patient. I need to see face validity, a reasonable level of evidence of benefit and a reasonable level of evidence suggesting little harm from the intervention.

Have a read and see what you think. Very very interested to know your opinions and happy to field any queries anyone might have.

And remember – POP in the ED? Think VTE. Don’t let your patient end up RIP. Like the Notorious BIG. Or Eazy E. Or Heavy D. Or ODB.

But not Warren G.

Fo’ real.

Dan

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