Clinical Case 124: Sand, Surf and Shattered Shin
Today’s case is maybe not unique to Broome. Representative of every Aussie town where teenagers, cars and boredom seem to intermingle to create crazy injuries… and sadly; occasionally tragic deaths.
Our 24 yo lad [almost always a male] presents to the ED with a bunch of his mates in the back of a ute [never a good sign]. They all seem very merry, aside from our hero.
He was “bonnet surfing”: a pastime in which an old car bonnet is inverted, tied to a length of rope and dragged behind a car on a beach / paddock / road. The aim of the game is for the young man to stay aboard the said bonnet whilst his mates try to dislodge him by driving it over obstacles such as tree stumps, sand dunes or edge markers…. genius!
The story: he was doing well until he hit a bump, flew in the air and his shin collided with a metal pole that was poking out of the ground. They estimate he was going about 45 km/hr when he hit. He did not hit his head and was able to stand on one leg… although the other leg is “munted” as we say in Oz.
So – here we are. We work about 1000 miles from the closest Orthopaedic services. This guy has a wound with bone and marrow on view. The wound is filled with sand and little bits of debris from the beach. As you are drawing up the ketamine to facilitate further inspection and immobilisation you are imagining the long days he will spend in a hospital somewhere fighting off infection, hoping his bones will heal and that the skin will survive. This is a nasty injury- one that could result in serious disability. Click here for more information on disability and benefits you can get from it.
Earlier in the day you flew a STEMI patient south and evacuated a sick neonate to the east… so all of the planes are in the air. There is going to be a long wait to get our man to somewhere that he can get his leg fixed.
He needs a washout and debridement ASAP. We have the ability to give him an anaesthetic and get the job started. So what exactly should we do?
Most big hospitals use all sorts of fancy irrigation systems, high-pressure pulse guns etc. Of course, we do not have these. So what is the best option in the bush for doing the best washout possible and hopefully allowing the wound every chance to get clean.
This is an interesting clinical scenario for me as we have always “done our best” in the bush with these sorts of injuries. I have always thought that we were doing OK, but felt that our capacity to do “best care” was limited by the kit we have available. So I was very interested to read this article in the New England Journal last week.
A Trial of Wound Irrigation in the Initial Management of Open Fracture Wounds: the FLOW Investigators. Dec 31 2015. NEJM
Lets PICO this one.
POPULATION: This was a big trial (by Orthopaedic standards) which randomised over 2500 patients to a 3 x 2 design. They were patients from 41 hospitals in Canada, USA, India, Australia and Norway. They had a variety of fractures and severities. About 2/3 had lower limb fractures and there was an even spread over severity grades – 37% were Gustilo grade II – like our man.
An interim analysis resulted in an expansion of the number of patients recruited in order to cope with follow-up failure which was about 10%.
The INTERVENTIONS consisted of 2 different irrigation solutions [delivered by one of 3 pressure kits]:
- Normal saline
- a 0.45% solution of castile soap in normal saline
and 3 different pressure set ups [using the 2 different solutions].
- very low: gravity
- low pressure : 5 – 10 psi
- high pressure: > 20 psi
There was a very high level of adherence to the protocol (96.5% – 98.8%) on the initial washout, however this did decrease to about 75% on the subsequent interventions.
CONTROLS There was obviously no “placebo”- so each group acted as controls. Washouts occurred on average about 9 hours after injury with good consistency across the groups. The analysis was stratified by injury severity to compare apples with mashed apples. All the other demographics aligned well across groups.
OUTCOMES The primary end-point was “reoperation within 12 months after the index surgery for promotion of wound or bone healing or treatment of a wound infection.” This is an interesting one as it can cut both ways – inadequate washout may lead to more infections and revisit to theatre, whereas aggressive washout was thought to interfere with healing, may cause tissue damage and subsequent healing problems. But I think this is a good patient-oriented outcome as it reflects the things we care about – the need to do more interventions for whatever the reason.
As secondary endpoints: non-operatively managed infection and wound-healing and bone-healing problems within 12 months after the index surgery. These were all predefined and seem like reasonable things to count in this sort of trial.
They used a Cox regression analysis which is the flavour for these longer term outcome trials.
When we look at the various Pressure of irrigation – very low, vs low vs high… NO DIFFERENCE. So it did not seem that the pressure of the kit used made any difference to these outcomes.
When looking at the irrigant used – saline vs soap in saline there was a difference seen. The plain saline group came out better than the soap group 11.6 vs 14.8 % needing a repeat procedure – so a number needed to harm (or benefit) of about 31.
Subgroup analysis suggested the harm was mostly seen in terms of non-union requiring implant exchange surgery. So a bone healing problem – of course this is a subgroup, so don’t quote it aloud!
The authors discussed a number of subanalyses – looking at various fracture sites and antibiotic usage etc. Not much to say about any of that though there was a trend to better outcomes for tibial fractures [like our patient] using very low pressure and straight saline.
For me this is one of those papers that helps us as rural / remote and under-resourced providers feel good about what we are able to do in our smaller centres.
Our patient can go to theatre and have a generous washout using 6 litres of saline with low-pressure irrigation and we are doing as well as we can.. and are practicing best care. Sure- he is still going to have 24 hours delay to getting his ORIF done – but he doesn’t need to wait for a good washout.
Let me hear your thoughts.
I wonder if the temperature of the saline may make a difference? Fridge room versus body temperature?