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More movies!

This is a great video of a widely used device which shows interaction problems - thanks for sharing Geoff! (I had seen the video before but didn't realise that Harold had put it on YouTube). I do like a good video

Firstly, is there really a problem? The anaethetist gets his job done after all.

Is this common? Intuitively one could imagine lots of interruptions where this timeout becomes an issue - perversely this may be at its worse at the most critical times! In more normal situations, how many restarts happen needlessly around the country/world everyday - in the video it happened twice in just one operation!?

Does the anaethetist just need more training, surely he should know how to use the device properly and press cancel rather than switching it on and off to restart.

Why is there this timeout function anyway? Couldn't the number entry be better designed so we don't have this problem and the need for training to cope with it?

How about a return to the thumbwheel rate switches, as used on Imed's first volumetric pump (the 922)? No room (excuse) for dumb mistakes there!

Meanwhile, anyone interested in (older) infusion devices in general might like to have a browse through this one.

This thread seems to have gone a bit quiet ...

... so here's another movie.

And here is the Q-Core website.

Been quiet on the forum for a while but the project is still moving along. To mark World Usability Day last week one of our professors gave a public lecture on usability, human error and patient safety so I thought I'd share it for those that are interested:

Very interesting! And thanks for sharing that with us.

Here are a few of the points I picked up there:-

1) Checklists are still given the thumbs-up (all engineers make lists, do they not?)
2) The realisation that nurses are too busy caring for patients to be focusing on technology
3) In general, hardware does not get Beta tested in the way that (most) software does
4) Some NHS Trusts are apparently negligent in the way they have un-checked (insufficiently trained, or just incompetent) people working in home-care settings

And, right at the end, the speaker could not give a definition for one of the words used throughout the presentation!

Meanwhile, here are a few questions of my own:-

1) How (and when) do manufacturers decide to introduce new equipment?
2) How is new (to market) checked out (in the UK) before being offered for sale?
3) Can anyone cite an example in recent times when it was the equipment (or its design) that was clearly at fault in any of the tragic cases reported in the press?
4) How about the ones that the Public were never told about?
5) In cases where equipment was clearly at fault (if any) ... would it have been likely that such faults would have been picked up during regular maintenance?
6) In cases where user error had tragic consequences ... would it have been likely that such errors would have been avoided by user training on the equipment involved?

Hi Geoff,

Thanks for taking the time to watch the video. Following some of your points I thought this might be interesting: I stand to be corrected but I think there is a gap between the current understanding of 'user error' and 'device error' that people don't readily look at. The default position appears to be that if there is a mistake and the device has done what it says in the manual then the nurse needs more training.

Psychological studies show that training is effective in reducing mistakes and knowledge based errors, but not effective in reducing slip errors. Knowledge based errors are things related to not knowing how to work something, e.g. not knowing how to operate a new blood glucose monitor. Slip based errors are errors associated with pressing the wrong button because they look the same, mixing things up like putting your orange juice in your cornflakes, forgetting where you have left the patient notes or controlled drugs cupboard keys etc.

The example (which is now dated so it wouldn't happen now but it shows the gap I am referring to): A nurse was in a very busy emergency situation where there are multiple audio alerts going off and she has to do too much. One of the infusion pump alerts is easily silenced by pressing the alarm silence button. The reason the pump alert was going off was that it wanted more information (I can't recall the reason). Whilst dealing with all the other things the nurse silenced this alarm three times as it repeatedly went off. However, she was actually raising the rate of the infusion each time she silenced the pump because she was hitting the up button rather than the silence button - this also meant the alarm was silenced.
The view of the expert reviewing this case was that it was clearly a user error i.e. the nurse should have been more careful about the buttons they pressed and should always check the device after interacting with it. Therefore there is no issue with the device and the nurse is blamed and needs more training (if she still has a job).
I thought that the design was at least partly at fault. The expert considered my view and conceded that the buttons could have been placed further apart. However, I wanted him to go further than this, why did the up button silence the alarm in this way which led to the mistake? A good design would have prevented this error. To me this interaction set the nurse up to fail.

I can't recall where I read it but we can use what is called a substitution rule in these instances. We don't know enough about the incident, but from what we do know, if we substitute that nurse with another nurse could we reasonably expect them to act in the same way. I would say 'yes' in this busy situation. This to me points to the design being at fault so it shouldn't only be classed as a user error.

So I would argue that this is not just a 'user error,' and it is not a 'device error' as it follows the instructions. I think there is a gap - a 'usability error' or 'design error' or 'interaction error' whatever you want to call it. I think these sorts of errors are confidently and wrongly categorised similar to the expert above, and that people don't readily look for usability issues. I'd be interested to hear people's views on this.

Hi Dominic

Have a look at this video ( in fact the site is good ) :

http://www.risky-business.com/talk-18-story-of-bethany-bowen-2.html

Note the comments about the investigation and the expert witness into this death by the mother ( very tragic )

Geoff these could answer some of your questions if you can get copies :

• Wang B, Fedele J, Pridgen B, Rui T, Barnett L, Granade C, Helfrich R, Stephenson B, Lesueur D, Huffman T, Wakefield JR, Hertzler LW & Poplin B. Evidence-Based Maintenance: Part III, Enhancing patient safety using failure code analysis, J Clin Eng, 2011, 36:72-84.

• Wang B, Fedele J, Pridgen B, Rui T, Barnett L, Granade C, Helfrich R, Stephenson B, Lesueur D, Huffman T, Wakefield JR, Hertzler LW & Poplin B. Evidence-Based Maintenance: Part II - Comparing maintenance strategies using failure codes, J Clin Eng, 2010, 35:223-230.

• Wang B, Fedele J, Pridgen B, Rui T, Barnett L, Granade C, Helfrich R, Stephenson B, Lesueur D, Huffman T, Wakefield JR, Hertzler LW & Poplin B. Evidence-Based Maintenance: Part I - Measuring maintenance effectiveness with failure codes, J Clin Eng, 2010, 35:132-144

@Dominic: good post!

Yes, we all make mistakes. But it is my sense that the "kit" gets blamed more often than not just to ease the embarrassment that other options would involve!

In the kind of examples you cite (and in the Real World), people often work in chaos. Sometimes they are under tremendous pressure, but sometimes (based on my own observations, at least) that crazy situation appears to be "self inflicted".

"Do one thing at a time (and do it properly)" wouldn't be a bad idea, in my view.

Easy to say sitting here, perhaps. But there needs to be a discipline (oh yes, there's that word again) about the workplace (any workplace), especially when working as part of a team effort, and/or in critical, stressful etc. situations.

So, what's the answer:- staffing levels! Back to the Numbers Game, then.

@George: thanks for that. Yes, I know a bit about "codes" (job codes, and the like). Believe me, when it comes to listing, numbering, classifying, categorising and coding ... then I'm your man! Sometimes to the n'th degree. How sad is that?

But take my tip:- sometimes analysing stuff to death can end up as mere procrastination. And, again, I write from great (chronic) experience of that, believe me.

If you can provide links to anything like those papers you mention, I would be very interested, Mate. Although I suspect that what those august academically inclined blokes are saying amounts to the same old stuff.

That's the trouble with research papers and the like:- when are we going to see some practical benefit from it all at the Sharp End?

1) What's the point of measuring maintenance if you're not doing it in the first place?
2) What's the point of measuring maintenance if you already know you're unlikely to ever have enough resources to do it properly?
3) What's the point of measuring maintenance when the Bean Counters (suits) can't understand what you're talking about anyway?
4) Etc. etc. ...

There's some interesting stuff at that link you gave, George. I'll take a look later on (when we're into the "quiet phase" of the day). But ... surgeons feeling infallible? Well, they need to be confident in their approach, do they not? After all, it's no good them dithering about all day, is it?

Surely competence and confidence go hand in hand. But when does confidence become over-confidence? And at what point does over-confidence become arrogance? And ... how often should they be let get away with it by the rest of the team? Now, there's a whole new topic for debate!

Thanks for sharing that video George - very moving and powerful.

There really is a need for people to admit their fallibility and try to create a better culture of openness and learning. There are big difficulties in changing the culture but after having just watched the video I wouldn't want to detract from its message. I hope others watch it too.

I posted this previously but this video by Martin Bromley makes a nice companion to Clare Bowen's tragic story: http://video.google.com/videoplay?docid=-6738698910009425483#
Martin Bromley is also trying to spread the lessons of the accident his wife was involved in through the Clinical Human Factors Group http://www.chfg.org/ . These people should really be applauded for their efforts.