EBME Forums Forums Maintenance Test Equipment Using IDA-4 Infusion Tester

it's been a while since I last used an IDA-4 but from my recollections the IDA-4 is not accurate enough to be used for calibration purposes. I'm sure we had a "do not use for calibration" label stuck on ours. We mainly used it for long term soak tests, i.e. MS16A at 2mm/h over 16-18 hours.
I beleive that our guys follow the manufacuter's instructions for the PPM.

As an aside, around 2002?, Baxter stated that the IDA was not a suitable method of accuracy determination for the flow delivery of the Colleague Volumetric Pump, and stated that its use contributed to reported inaccurate readings.

The EBME Department I was working in, were instrumental in identifying under delivery, possibly caused by shuttle mechanism drift and changing the manufacturing specification on the giving sets and raised this issue with Baxter and the MDA (as was).

But on a scheduled visit to Baxter Northampton, what did I see being used in the calibration bay by the Baxter Technicians?

Using the IDA for checking purposes is perfectly acceptable I have been using my IDA 2 for many years. An experienced engineer should be able to determine from using the IDA if calibration is required, then I would be inclined to follow the recommended procedure. Going back to the point 'you have to follow the manufacturers recommendations', Nellcor 560 manual recommends the battery is changed every 2 years we all do that dont we

Just checked the IDA manual, page 3 if you are interested. The accuracy is stated as either 1% or 2% (+/-1lsd)depending on the flowrate & test volume. It may be acceptible for calibrating volumetric pumps but isn't good enough for syringe drivers.
Burette or scales & stopwatch are best option (and cheapest!).

Good Point BiomedBill, Alaris GH pump is a Syringe pump and Alaris GP is a Volumetric pump.....

I would have thought scales are less accurate than 1% unless you have some high quality laboratory ones.
And can you read a burette to better than 1% accuracy? If you infuse a full 50ml syringe you will have to be able to read it to less than 0.5ml and be able to operate a stop watch to that accuracy as well. And remember if you use two instruments to measure anything you have to add the two inaccuracies which means you have to be able to measure each one to 0.5% to make an overall 1% apparatus.
May be the IDA is not so bad after all.
Robert

Our burettes are graduated to 0.1ml, can't speak for anyone else's of course.

In the case of the Signature and Alaris GP pumps, you calibrate according to the volume delivered rather than the time. In fact, the GP PVP doesn't actually specify a delivery time.

So far as syringe pumps go, I would have thought it better to use a linear gauge than measuring fluid delivery, since the linear guage would take out small variations in the syringes.

The other point is you are supposed to use a calibrated giving set......

Sometimes you have to take a step back and ask yourself what it is you're trying to achieve.

How accurate are the pumps (drivers, whatever) supposed to be? And what about repeatability of the results?

What do the specs. say? Then how accurate do they need to be (in the Real World, that is); how accurate is your test kit (or testing method), and how much time have you got? Are you just "checking", "testing" ... or "calibrating" to the n-th degree?

You also need to decide what you should be measuring (what is important); volume delivered, flow-rate, occlusion alarm pressure etc., etc. Pumps work in different ways, and some designs emphasise different aspects. And all the well-known test kit (and testing methods) have strengths and weaknesses.

Volumetric pumps and syringe pumps are doing different things. You need to understand what it is you're trying to do. Could that be the Golden Rule?

This is why I took a step back from infusion devices. Too many conflicting views for such a simple device, added to which we have to put up with over reliance on software and never ending agruments about drug protocols and things like Guardrails etc.
A simple piece of medical equipment complicated by fear mongering (sorry, clever marketing!) and a " we've got a processor let's invent stuff for it to do whilst it is carrying out a simple task" attitude.
These were the first devices that got me into thinking that we need to temper (computer) technology by keeping an eye on the function of the device in question. Infusion devices have gone through many iterations whereby they rely more on the ability of a software programmer than the physical engineering required to make a safe, accurate & durable (emphasis on the last one) device.

Sorry to go a bit off topic, rant over.

Where did I put that burette?