PPM intervals - how do *you* decide yours?!
Where you don't stick to manufacturer's recommendations , how do you justify & document the reasons?

Start by using the manufacturers interval, and recording any defects or adjustments that have to be made. If the instrument is constantly working within specification you now have the documentation to justify the extension of the period between ppm visits.

What about the manufacturers "life" for some parts? If they say you have to change the O rings every 3 months, say, but they never look knackered, can you justify leaving them in? Do you just extend it to 6 months and then see what they are like? Who carries the can if one fails during use and causes an incident? The failure might be nothing to do with the age of the part, but you can bet they'd use it as a handy hook to hang you on!
Sometimes, the only way to find out what a parts REAL life expectancy is, is to leave it in use till it fails - but you can't do that with medical equipment! Can we trust the manufacturers to give us accurate information, or is it in their interests to sell us lots of O rings and/or justify their engineer coming in every few months?

Do we really know the inner workings of the humble 'O'ring? If the manufacturer says change them, on life support equipment I'd change them..pay pence now than pounds later on....

Julian
It is not just the cost of the o ring, what about manhours? I think that if the device usage is normal, service as recommended. If it is low then you have justification to lengthen the service interval.
As Simon said (no pun intended)
Justify your decisions. You could increase the service interval to 6 months and monitor the breakdown levels between servicing. If they do not go up you are justified in what you have done.

The worst scenario is that you extend the service interval to see what happens - something fails and causes an incident (maybe even kills somebody) - and then whose in deep trouble ? I've heard stories of EBME managers being pilloried by coroners over a device failure where the PPM was done in-house, but on extended periods and the failure wasn't even on a part which would have been changed during a PPM !
We are at risk of being the scapegoat when something goes wrong, but if the manufacturer is servicing it, you just waive the service report at the coroner - and it goes through on a nod !
They always assume that if we are doing it, it's being done on the cheap and corners are being cut. I've seen what some manufacturers engineers do for a service and it bears no relation to what it says in the manual. When you querry it, they say they work to a PPM schedule which isn't in the manual - but won't tell you what it is ! We've tried to force them to tell us by getting Supplies to insist that we need to know what we are paying for under the contract, but they normally don't get anywhere either. The usual excuse is that the PPM schedule is an internal document and is not available to anyone outside the company. One even claimed that it contained sensitive information which may be of use to a competitor ! !
Do you suppose they mean us ?

Roy
I agree that even manufacturers don't always follow their own guidance.
At the end of the day you need broad shoulders and good reasons as to why you moved away from the manufacturers schedule. Write these down, look at the risks, and decide.
We follow our own service procedures based on years of experience, and common sense.
Any coroner would have to take into account your reasons why you follow your own procedures.

Reminder! All this talk of coroners and getting into trouble, shouldn't the BIG issue be that you don't want to injure/kill someone? and this should be at the forefront of your mind when working with medical equipment! You can insure yourself against litigation, but you can't turn back the clock after a death or injury.

Controversial topic or what? Looks like we're all doing our own thing again!
Does anyone have any PPM interval limits they would never exceed for more critical stuff, like defibs say, regardless of previous reliability?

As we weren't funded or staffed to do PPM on all the equipment (we were just about coping with the repairs !) we persuaded users to put the critical stuff on contract. The defibrillators have almost all been replaced by H.P. Codemasters (not my choice ) which have a five year cover deal built into the price, but we are now doing all the patient ventilators and anaesthetic machines in house. We stick strictly to the manufacturers schedule.
I agree absolutely with the point made further back - we should be doing everything possible to prevent incidents and death / injury rather than worrying about who gets blamed. Err on the side of safety !

[This message has been edited by Roy (edited 20 September 2000).]