Auditing in-house laboratory slide staining protocol to reduce contamination

Hello and welcome to my podcast. My name is Claire Oglesby and when I entered the RCVS Knowledge Awards I was clinical nursing manager at Gower Vets in South Wales. As one of our services we offered in-house microscopy for FNAs and ear swabs. Normally the vets would stain these themselves using the three-stage DiffQuik system and dipping the slides into the containers.

However, one day a colleague approached me to say that three false positive results had been reported in as many months. This delayed diagnosis and treatment. It was really disappointing and we sat down to have a chat to see where we were going wrong. We thought it could be due to the stains getting contaminated.

So I decided to try introducing jars with necks that were narrower than the slides and supplying perpets to flood the slides with the stains. In addition, I made a stain bath from a wire rack and a container of cat litter underneath. The litter absorbed any excess stain and wash and it could be easily changed, making it also more environmentally friendly than rinsing over a sink like we used to do.

I introduced the new equipment with an SOP and I talked to my colleagues through the new process at a team meeting, making sure that I emphasise the potential benefits. I was really fortunate to work in a clinic where change was welcomed and the whole team were on board with the new process from the start. After a few months, I carried out an audit and found our results were more reliable.

In addition, the team were really in favour of the new rack and litter set up as the practice encouraged environmentally friendly methods. So in fact, there was a double advantage. However, I did find that the lids of the jars were often being left off and the stains were evaporating quickly, so we were using much more than before. I made a further change, which was putting the stains into wash bottles clearly labelled A, B and C.

Following that, the SOP was updated and communicated again to the rest of the team.

The new method eliminated any contamination and it also reduced the evaporation of the stains. So I carried out a final audit cycle and found that the changes had been adopted across the whole team. We had successfully eliminated all the false positives. It was so rewarding to be able to improve our processes and get better outcomes. This is something that can be adopted by any practice with very little equipment.

It’s low cost and only takes a quick revision of staining methods. The whole process was easy to follow using the resources on the RCVS Knowledge website and it was written up using a template for submitting to the wards. I would thoroughly recommend having a go for yourselves as even small changes in practice can really bring about positive change. Thank you for listening.