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Stroke Ambulances are an example of what Rev Père Lafontant often refers to as “appropriate technology”.
“Do you know what ‘appropriate technology’ means?” He asks
“It means good things for rich people and shit for the poor.”
Why is this the case?
Well...
“Do you know what ‘appropriate technology’ means?” He asks
“It means good things for rich people and shit for the poor.”
Why is this the case?
Well...
There are a few issues at play.
1. The flagship problem
2. Effect sizes and marginal gains
3. Research competition
4. Resource allocation and restriction
1. The flagship problem
2. Effect sizes and marginal gains
3. Research competition
4. Resource allocation and restriction
The flagship problem:
What is the issue that stroke ambulances are trying to solve?
Well there are a few issues, but the most compelling one is that
‘Stroke patients have the best outcomes when they get early clot retrieval (or sometimes thrombolysis)”
Fairly straightforwards
What is the issue that stroke ambulances are trying to solve?
Well there are a few issues, but the most compelling one is that
‘Stroke patients have the best outcomes when they get early clot retrieval (or sometimes thrombolysis)”
Fairly straightforwards
In order to make this happen
We need to do everything possible to
A. Decrease the time between symptom onset to stroke recognition.
B. Decrease the time between symptom recognition to CT scan
And
C. Decrease the time between CT scan to clot retrieval (...or lysis
)
We need to do everything possible to
A. Decrease the time between symptom onset to stroke recognition.
B. Decrease the time between symptom recognition to CT scan
And
C. Decrease the time between CT scan to clot retrieval (...or lysis
)
Here is the issue.
Parties often call for an ambulance and get taken to hospitals that don’t have clot retrieval or super specialist stroke services.
So they need transfer
Which causes delays
And hospitals move slowly
Parties often call for an ambulance and get taken to hospitals that don’t have clot retrieval or super specialist stroke services.
So they need transfer
Which causes delays
And hospitals move slowly
So, the argument has been made that by having a mobile stroke unit we can triage appropriately in the field and save time!
Get them to a hyper acute hospital for clot retrieval first time...or even lyse them in the field in some cases-(this has some, but very minimal benefit)
Get them to a hyper acute hospital for clot retrieval first time...or even lyse them in the field in some cases-(this has some, but very minimal benefit)
The flagship issue boils down to this:
Why have you spent 10-20 million dollars creating an ambulance that can see about 300 patients a year at best, instead of actually reforming your health system pathways and developing hyper acute stroke centre bypass protocols?
Why have you spent 10-20 million dollars creating an ambulance that can see about 300 patients a year at best, instead of actually reforming your health system pathways and developing hyper acute stroke centre bypass protocols?
It’s flashy
It is a media grabber
Health ministers like to point at it and say “look how great we are”
It’s a flagship. But like many navy flagships throughout history, it is no representation of the capabilities of the rest of the fleet (or in this case, the health system)
It is a media grabber
Health ministers like to point at it and say “look how great we are”
It’s a flagship. But like many navy flagships throughout history, it is no representation of the capabilities of the rest of the fleet (or in this case, the health system)
So,
It is distasteful in that it benefits few, at great cost, and is a distraction from the real thankless work of system reform.
It is distasteful in that it benefits few, at great cost, and is a distraction from the real thankless work of system reform.
Issue 2- Effect sizes and marginal gains:
“How can you support mobile ECMO units or helicopter critical care teams and not stroke ambulances?”
Well
Let’s discuss the effect size of the intervention.
“How can you support mobile ECMO units or helicopter critical care teams and not stroke ambulances?”
Well
Let’s discuss the effect size of the intervention.
If we examine the ECMO literature, it is impressive.
It appears to radically change outcomes in refractory OHCA.
Its impressive effect sizes come down to patient selection.
Stroke ambulances also engage in patient selection. They have to. All specialist resources must.
It appears to radically change outcomes in refractory OHCA.
Its impressive effect sizes come down to patient selection.
Stroke ambulances also engage in patient selection. They have to. All specialist resources must.
The difference here is that when we examine the effect size or rather, the gross impact of the intervention, ECMO teams, HEMS in rural areas, and other similar assets are demonstrably beneficial. They radically improve outcomes for their select patient group.
Stroke ambulances do not.
The entirety of the literature on stroke ambulances relies on an argument of marginal gains and cost effectiveness where the total DALY are reduced by a number which is significant if you squint hard enough.
The entirety of the literature on stroke ambulances relies on an argument of marginal gains and cost effectiveness where the total DALY are reduced by a number which is significant if you squint hard enough.
If one is to make the argument that stroke ambulances are cost effective because they save the health system and improve outcomes through marginal but cumulative gains then fine.
But one must then put stroke ambulances everywhere to have an actual impact on population-wide outcomes
I would think there are more cost effective interventions than this.
I would think there are more cost effective interventions than this.
Issue 3 - Research competition:
There are now more than 15-20 stroke ambulances programs worldwide. Each of whom has yet to demonstrate any Singh docs to breakthrough. Each of whom have invested tens of millions.
There are now more than 15-20 stroke ambulances programs worldwide. Each of whom has yet to demonstrate any Singh docs to breakthrough. Each of whom have invested tens of millions.
And each of whom seem to believe that their solution is somehow different to everyone else’s and superior.
“Sure their program didn’t demonstrate p=<0.05 benefit but OURS will!”
This is a classic case of multiple teams vying and competing for a phantom prize.
“Sure their program didn’t demonstrate p=<0.05 benefit but OURS will!”
This is a classic case of multiple teams vying and competing for a phantom prize.
Competition is good
Certainly we value reproducibility in science.
But in a world of limited funds and limitless needs, stroke ambulances are not where every rich nation needs to spend our precious research budgets
Certainly we value reproducibility in science.
But in a world of limited funds and limitless needs, stroke ambulances are not where every rich nation needs to spend our precious research budgets
Finally Issue 4 - Resource Allocation and Restriction.
The primary issue at play here is that stroke ambulances are manifestly an example of unjust allocation of resources.
The primary issue at play here is that stroke ambulances are manifestly an example of unjust allocation of resources.
Why so?
At least a metropolitan hospital can receive patients from afar and treat them inside.
A stroke Ambulance is SEVERELY location restrictive.
It can ONLY serve the small geographic region that can be reached within about 45 minutes of driving.
At least a metropolitan hospital can receive patients from afar and treat them inside.
A stroke Ambulance is SEVERELY location restrictive.
It can ONLY serve the small geographic region that can be reached within about 45 minutes of driving.
How is an ECMO or critical care team any different?
These teams can utilise multiple transport platforms to access patients if designed correctly.
Hell, even an ECMO bus can at least serve regional patients a few hours drive away for inter hospital retrieval!
These teams can utilise multiple transport platforms to access patients if designed correctly.
Hell, even an ECMO bus can at least serve regional patients a few hours drive away for inter hospital retrieval!
If one was to put a CT scanner on a helicopter this would be a completely different argument.
In fact, I would be quite supportive of this because of its ability to seriously impact stroke to clot retrieval times for rural patients.
Potentially the difference between tPa and EVT
In fact, I would be quite supportive of this because of its ability to seriously impact stroke to clot retrieval times for rural patients.
Potentially the difference between tPa and EVT
But unlike a tertiary hospital, or a mobile ECMO team, or a HEMS Team who can go by 
or by 
, a stroke ambulance can only ever benefit a small group of people in a small area, in a very small way.
Whilst staring in the face of glaring health outcome inequality
or by , a stroke ambulance can only ever benefit a small group of people in a small area, in a very small way.Whilst staring in the face of glaring health outcome inequality
And that is why I think Stroke Ambulances are essentially an emblem of unethical and unjust resource distribution, and a ploy by joint venture government and interest groups to attract buzz instead of doing the real work of system reform.
