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Research and Projects

PenCHORD - Determining the required size of a Clinical Decision Unit at Royal Devon & Exeter Hospital

Who is involved?

Theme: Evidence for Policy and Practice
Status: Live


The Royal Devon & Exeter Hospital (RD&E) would like to introduce a Clinical Decision Unit (CDU) to support processes at their A&E department. Initially, it was planned that the CDU should have space for four patients at any one time; however, it is not known whether this is the most efficient size, as the number of patients who would be suitable to be referred to the CDU varies considerably at different times. 

This modelling project will assess what size of CDU is most suitable, and what the effect of having a CDU would be on patients’ overall length of stay in the A&E department. It will also assess the optimum opening times for the CDU.

The project developed from an HSMA project by Alaric Moore, Performance Improvement Manager at the RD&E, which worked with clinicians and patients to map out the processes involved in A&E treatment at the hospital. This research highlighted the complexity and interdependencies of the current processes, providing vital groundwork for PenCHORD’s project.

Project objectives

The project has two key objectives:

  1. To produce a decision support tool that accurately reproduces the current level of patient attendance at A&E. This tool should allow the team to test out different admission policies for admitting patients into a CDU whilst taking into account different opening hours. This tool will be a discrete event simulation model which is a common choice when modelling patient flows in hospital departments such as this one. 
  2. To identify how different strategies for admitting patients into the CDU would affect its utilisation, particularly over time. The project team will also analyse what the effect would be if the CDU was only available at certain times (e.g. between 8am and 8pm) in contrast to a 24/7 provision. The final outcome will be a risk profile which quantifies the probability that a given number of beds in the CDU would be exceeded. 

Project activity

A prototype simulation model has been built, using historic anonymised data records in order to replicate the current activity in the hospital's A&E department. Together with the department’s Cluster Manager and Lead Consultant, admission policies have been developed which are currently being evaluated in extensive simulation experiments.

Anticipated outputs

The project team’s report to the Royal Devon & Exeter NHS Foundation Trust will feed into scoping for the CDU. This study aims to help inform a £multi-million decision around strategic planning in A&E at the Trust.

When the CDU is implemented, PenCHORD aim to track how much it is used and the rate of admissions, and compare this to the modelling outcomes, with a view to publishing a paper on the project. 

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Royal Devon & Exeter NHS Foundation Trust
Alaric Moore - Performance Improvement Manager, Operations Support Unit
Laura Custerson - Cluster Manager Acute and Emergency Medicine