Sorry folks, more on that 8 minute response time stuff. I keep coming across more ‘papers’. I ploughed through 2 of interest tonight. Firstly: Effect of reducing ambulance response times on deaths from out of hospital cardiac arrest: cohort study. Pell et al – available from BMJ June 2001.
This is the paper I remembered that had an analysis of how we got the ‘mythical’ 8 minutes. The study looked at “all out of hospital cardiopulmonary arrests due to cardiac disease attended by the Scottish Ambulance Service during May 1991 to March 1998″.
Results Of 13 822 arrests not witnessed by ambulance crews but attended by them within 15 minutes, complete data were available for 10 554 (76%). Of these patients, 653 (6%) survived to hospital discharge. After other significant covariates were adjusted for, shorter response time was significantly associated with increased probability of receiving defibrillation and survival to discharge among those defibrillated. Reducing the 90th centile for response time to 8 minutes increased the predicted survival to 8%, and reducing it to 5 minutes increased survival to 10 – 11% (depending on the model used).
Conclusions Reducing ambulance response times to 5 minutes could almost double the survival rate for cardiac arrests not witnessed by ambulance crews.
In their discussion they note:
Survival of out of hospital cardiac arrest in the United Kingdom is up to three times lower than that in some other countries. The American Heart Association described the “chain of survival” concept in which survvival depends on several factors including public awareness of symptoms, early basic life support by bystanders, rapid access to emergency medical services, and prompt defibrillation. Survival from cardiac arrest can be increased sixfold by providing first line responders with defibrillators.
Hey, guess which parts of the ‘chain’ we don’t cover in the UK. How about BLS in schools? Ooohhh don’t get me started on something else!
So, on to paper 2: Measurement of Healthcare Output and Productivity – Ambulance Response Times for Patients with Cardiac Arrest – DoH December 2005. Get a PDF copy.
This paper mentions that elusive ORCON study group report, Review of Ambulance Performance Standards:
A DH report, Review of Ambulance Performance Standards, July 1996, examined the health benefits to be gained by improving response times. The report presented estimates of the benefits of moving from the existing 1996 standard of 50% of emergency calls responded to within 8 minutes, to the current target of 75% of Category A calls responded to within 8 minutes, and an intended longer term target of 90% of Category A calls responded to within 8 minutes. [my emphasis]
The authors quote extensively from the first and produce all sorts of ‘estimates’ of Lives Saved and Quality Adjusted Life Years (QALYs) saved, and manage to place a financial costing on these ‘improvements’. For me the real problem was that they never, ever seemed to consider whether it would be physically possible to improve response times. Perhaps, in one of those parallel universes I posted about on Monday the ambulance could actually charge out the yard the second the phone rang in Control, and assuming it could do 0-60mph instantaneously and there were no obstacles (traffic lights, roundabouts, idiotic motorists) and supposing we got straight to the address without faffing about trying to find the number. We could still only get to calls within an 8 mile radius of the ambulance station. How many stations and ‘hot spots’ do these guys thing there are. They no doubt live in the same ‘cloud cuckoo land world‘ as commissar Hewitt.
Anyway enough ranting. Hidden away in the conclusions –
These estimates are based on a DH report from 1996, which may be somewhat outdated. – so that ORCON report is flawed???
However, the estimates presented are for cardiac arrest patients only and relate only to surviving the immediate event, rather than wider clinical outcomes for surviving patients. These patients represent less than 5% of the total number of Category A responses. [my emphasis]
So, once again we find that the 8 minute response time is based on survival for out-of-hospital cardiac arrests only – yet 95% of A category responses are for something else (usually rubbish) but we still have to respond in 8 minutes. Heaven knows what we’ll do if some
nutter, sorry Health Secretary ever gets the crazy idea to make it 90% of A cat calls in 8 minutes.