Bespoke rulers invented by hospital pharmacy staff led to 35% reduction in loss of controlled liquid drugs

Northampton General Hospital NHS Trust — where the rulers were trialled — says the device could save the NHS £1.2m a year if used across all NHS hospital trusts.

Image of the ruler device, which fit a range of controlled drug bottles — The first self-made iteration of the ruler device was developed by Siobhan Abrahams, an advanced clinical pharmacist at Northampton General Hospital NHS Trust

A ruler-type device for measuring the volume of controlled drug liquids, invented by two hospital pharmacy staff, reduced the loss of drug volume by 35% during a one-year pilot at Northampton General Hospital NHS Trust.

The ruler was developed by Rosemary Griffiths, a registered pharmacy technician and former dispensary manager at the trust, and Siobhan Abrahams, an advanced clinical pharmacist at the same trust, to fit a range of controlled drug bottles.

A press release, published by Northampton General Hospital NHS Trust on 17 March 2022, explained: “Unlike a standard ruler that measures length in consistent metric/imperial hatch marks, the marks on these rulers have been calculated so that they alter in line with the bottle shape.”

The rulers were initially trialled across Kettering and Northampton General Hospitals, which together form the University Hospitals of Northamptonshire NHS Group.

According to the press release, use of the tool resulted in the 35% reduction in unaccounted loss of controlled drug liquids, “saving money and improving patient safety”.

The device had the potential to save the NHS £1.2m a year if used across all NHS hospital trusts, the press release added.

Griffiths explained that the idea for the rulers came about when Abrahams showed her a self-made cardboard ruler that she used to calculate the volume of controlled drug inside each bottle.

Griffiths said that this “light bulb moment” then led them to consider whether they could come up with a ruler that others could use.

Prior to this, Griffiths said: “Working at Northampton General Hospital, our audits showed unaccounted loss on drugs, and it was hard to be sure why. It got me thinking that there had to be an effective way to minimise it.”

Griffiths has since set up a company called eezycd, which manufactures and distributes the rulers.

There are currently 35 types of ruler available, with orders having been placed by 17 hospitals and healthcare institutions, including Great Ormond Street Hospital.

The company also offers a consultancy service that alerts customers and issues an updated ruler if a manufacturer changes the shape of a controlled drug bottle.

Emma Davies, advanced pharmacy practitioner in pain management at Cwm Taf Morgannwg University Health Board, said the innovation was useful.

“That they’ve been used in practice and shown to reduce errors is a big factor for me — they’ve been trialled and carefully thought through,” she said

“I’d think anything that helps busy practitioners to undertake controlled drug checks more efficiently, without having to tip out contents and replace (which automatically reduces accuracy), and which are dead easy to use and make sense of, is a great idea and I wish Siobhan and Rosemary all the best with the venture.”