Esri European User Conference´s presentation by Grahame S. Davis, from Centre for Infection Prevention and Management of Imperial College London.

1. Converting Hospital Floor plans into
Maps for Spatial Analysis in GIS
Grahame S. Davis, MSc
Centre for Infection Prevention and Management (CIPM)
Imperial College London

2. About CIPM
• Tackling the issue of healthcare acquired infection (HCAI) via a
multidisciplinary approach that includes:
organisational research
social marketing
epidemiology
laboratory-based programmes
education
• 4 work streams:
Innovation Adoption & Behaviour Change
Network in Clinical Infection & Diagnostics
Infection Surveillance
Capacity Building

3. Outline of Presentation
1) Healthcare Acquired Infections (HCAIs) in UK
2) 3D Analysis Theory using GIS
3) Development of hospital floorplans
4) Future Work

4. 1) HCAIs in UK
• Serious problem in most countries with surveillance worldwide
• Estimated in the UK, that 8.2% of patients will become infected whilst
in hospital (1,2)
• Costs estimated at around £1billion per year (3)
• In NHS, this equates to:
increased waiting time
decrease in availability of beds
reduced overall resources (4)
(1) Stone, PW. Am J Infect Control 2005 (3) Kearney G. J Environ Health 2008
(2) Kho, A. Am J Infect Control 2006 (4) Kistemann, T. Int J Hygiene Environ Health 2000

5. 1) HCAIs in UK
• HCAIs cause severe complication in patients & lead to otherwise
preventable mortality
• Utilisation of spatial analysis within a hospital setting could provide
better understanding of the factors related to HCAI infection
transmission.
• This could improve control of HCAIs through:
faster identification of possible outbreaks
reducing the likelihood of transmission
• Yet mapping indoors has a number of challenges.

6. 2) 3D Analysis Theory using GIS
• Small area-analysis of micro-spatial environments has expanded
• Recent applications include:
Urban planning
Analysing layouts of buildings & how they are used (5)
Improving response to emergencies within buildings (6)
(5) Lee, J. Geographic Information Science 2004 (6) Kwan, MYW. Hong Kong Journal of Paediatrics 2009

7. 2) 3D Analysis Theory using GIS
In Health::
• Mapping distribution of SARS within a vertical indoor environment
• Micol et al. created a prototype of a Hospital GIS dedicated to the
investigation of HCAIs (7)
• Kruger et al. propose the use of GIS as an early warning system for the
emergence of drug-resistant strains (8)
• Kho et al. created medical dashboard linked into hospital databases (9)
(7) Micol, R. Proceedings AMIA Symposium 2002 (8) Kruger, H. Abs of the ICAAC 2002
(9) Kho, A. Am J Infect Control 2006

8. 3) Development of Hospital Floorplans
The Study Area
• Imperial College Healthcare NHS Trust in London.
• One of the largest NHS Trusts in UK
• 3 major hospitals: • 2 specialised hospitals:
Charing Cross Hospital Queen Charlotte’s & Chelsea
Hammersmith Hospital Western Eye Hospital
St. Mary’s Hospital

9. 3) Development of Hospital Floorplans
Steps in Design
• Development of Floor plans
• Introducing The 3rd Dimension
• Transfer into ArcGIS

10. 3) Development of Hospital Floorplans
Floorplans
• Architectural floor plans for our 3 main hospitals
• Stored in CAD (Computer-aided Design) format.
Ward Surveys
• Visual surveys carried out of clinical areas to ensure accuracy of the
floorplans, encompassing around 100 wards.
• The main discrepancies observed were designation of side room use,
sink sites and removal of minor interior walls.

11. 3) Development of Hospital Floorplans
Adaptions in AutoCAD
• Used for structural information by the Estates department
• Range of symbols and notations had to be removed prior to conversion
for use in ArcGIS.
• The layers removed include:
architectural data (i.e. room codes)
notations of room areas (i.e. ceiling heights)

12. 3) Development of Hospital Floorplans
3D representations of floorplans
• Floor plans need to be combined into a 3D structure
• Values for heights of the walls & ceilings defined within the CAD
floorplans
• Used to create 3D representations of the individual floors by extruding
the surfaces to the required vertical height
AutoCAD

13. 3) Development of Hospital Floorplans
Transfer to ArcGIS
• AutoCAD files can be directly imported into ArcGIS
• To use the files for mapping, the layers had to be separated
• Achieved by extracting each layer individually & exporting it as a
separate shape file

14. 4) Future Work
Creation of 3D Buildings
• Floor plans will be combined to create a 3D representation of the
hospital buildings.
• Requires a 3D coordinate that incorporates a z coordinate related to
the elevation i.e. (x, y, z) or (1m, 3m, 5.7m).
• Ceiling heights which were used for individual floors lack information
on the inter-floor distances
• These 3D building maps will then be transferred into ArcGIS.
.

15. 4) Future Work
Considerations of Indoor Mapping
• Development of an accurate 3D geo ref system for the interior of
buildings
• Method to measure distance across floors within the building
• Indoor environment involving physical structures:
Relative path distance
• Modelling connectivity relationships of internal structures:
horizontal directions (on a floor) defined by corridors
vertical direction (among floors) defined by stairways & elevators.

16. 4) Future Work
Testing With Trial Data
• Use of generated & real datasets to test model
• Necessary to identify issues or highlight required revisions
• Maps to be updated dependant on alterations to the hospital
environment
Display of Data
• Must define how data will be displayed to ensure standardisation of
results

17. 4) Future Work
Analysis of HCAI Distribution
• Utilisation of these maps as a research tool identifying:
Potential clusters
Areas of interest for further investigation.
• Utilise ArcGIS extensions to visualise & analyse the distribution of cases
• Evaluation of clusters will take two steps:
Statistical analysis to determine if ‘true’ cluster
Epidemiological investigations to determine significance of localised risk
factors.

18. Conclusion
• Production of significant information by GIS relies on the accuracy & level of
detail of the data available
• Requires up-to-date maps of the wards & accurate locational data for the
cases or factors of interest
• Dynamic hospital environment where patient movement, bed relocation and
ward closures must all be addressed
• There are many other issues that may arise during the development of these
maps

19. Conclusion
• The application of GIS in hospital based healthcare is an area of growing
interest.
• The utilisation of spatial analysis within a hospital setting could provide better
understanding of the factors related to HCAI infection transmission and help
improve control

20. Acknowledgements
• I would like to thank my supervisors Dr. Lydia Drumright and Dr. Nick
Sevdalis for their help and support.
• I would also like to thank the numerous people within the Infection
Prevention & Control teams and the Estates department for their on-going
help with my project.

21. Want to know more?
Grahame S. Davis
Centre for Infection Prevention and Management (CIPM)
Division of Infectious Diseases and Immunity
Department of Medicine
8th Floor Commonwealth Building
Imperial College London
Du Cane Road
London W12 0NN
Email: g.davis10@imperial.ac.uk