Xiaolan Xie, Vincent Augusto, Lei Wang.
ORAHS 2006

• Presentation of the CHU-Saint-Étienne
• Goal of the study
• Modelling the flows of the current pharmacy department
• Simulation and first results
• Engineering the future pharmacy organisation (in progress)
• Conclusion and future work
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
2

• 1921 beds with 1142 for medical, surgery and obstetric activities.
• 6550 workers.
• 56 clinical services.
• 18 medico-technical services.
• 4 main hospitals : Nord, Bellevue, la
Charité, Saint Jean Bonnefonds.
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
3

27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
4

The CHUSE has currently two pharmacy departments :
– the central pharmacy in hôpital Nord which delivers :
• Short-stay departments.
– The pharmacy annexe of Bellevue which delivers :
• Short-Middle and long-stay departments.
• Emergency department.
Only medication delivery flows are taken into account in this study.
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
5

Delivery of short-stay departments Daily deliveries from outside suppliers
Mobile
Pharmacy department of Hôpital Nord medicine-chests
Weekly deliveries
Delivery of middleand long-stay departments
La Charité – Saint-
Jean-Bonnefonds
27/07/2006
Pharmacy department of Hôpital Bellevue
Mobile
Medicine-chests
Xiaolan Xie - Vincent Augusto -
Lei Wang
6

• Presentation of the CHU-Saint-Étienne
• Goal of the study
• Modelling the flows of the current pharmacy department
• Simulation and first results
• Engineering the future pharmacy organisation (in progress)
• Conclusion and future work
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
7

Modernisation process of CHUSE :
– Modification of the medical and surgery departments organisation ;
– Activities are being grouped into its largest hospitals :
• Hôpital Nord ;
• Hôpital Bellevue.
– Merging the 2 pharmacy departments into one in Hôpital Nord.
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
8

 Decision-aid for re-engineering the pharmacy department of CHUSE
(april – september 2006) :
– Step 1 : Modelling and simulating the current delivery process ( as-is system ).
– Step 2 : Reengineering the organisation of the future central pharmacy ( to-be system ) : answer questions and solve basic transport problems.
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
9

• Presentation of the CHU-Saint-Étienne
• Goal of the study
• Modelling the flows of the current pharmacy department
• Simulation and first results
• Engineering the future pharmacy organisation (in progress)
• Conclusion and future work
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
10

There is no specific modelling tool for health care systems.
To the contrary, there is a lot of industry modelling tools :
– GRAI ;
– ARIS ;
– SADT ;
– UML…
A comparison of existing modelling tools with healthcare applications is performed in [Trilling et al.
, 04] .
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
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UML is a tool (not a methodology) of object oriented modeling (OOM).
• Numerous applications : software engineering, industrial engineering, etc.
• Rich formalism (9 types of static/dynamic diagrams), easy to understand.
• UML is used in a few healthcare studies
[Vasilakis et Kuramoto, 05] .
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
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Activity diagrams are used to model flows.
Example of a simplified surgery process :
Every entity is an object
Patient id : integer lastname : string firstname : string takeAppointment() attributes operations
(transporter)
Transport
(surgeon, OR)
Surgery
(recovery bed)
Recovery
Needed resources
(transporter)
Transport
Entry point
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Activity
Xiaolan Xie - Vincent Augusto -
Lei Wang
Exit point
13

• 6 main processes :
• Supply of mobile medicine-chests ;
• Regular supply of nominated medicines (different in Nord and
Bellevue) ;
• Emergency supply of nominated medicines ;
• Patient flow at the individual dispensary ;
• Medical solutions delivery ;
• Reception process (only in Hôpital Nord).
• 5 types of resources :
• Pharmacists (5) and interns (2);
• Assistants (17);
• Storekeepers (8) and transporters (4).
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
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Supply of mobile medicine-chests (M.C.)
Entities : mobile medicine-chests based on planning
(transporter)
Transportation to pharma.
based on distance servicepharmacy
(assistant)
Inventory assessment.
small : 15~45 min.
med. : 20~40 min.
big : 35~50 min.
(assistant)
Collect of med.
Fill the m.c.
small : 25~35 min.
med. : 20~60 min.
big : 40~70 min.
(transporter)
Transport to its service based on distance servicepharmacy
The supply planning gives :
• the day and hour of arrival ;
• the name of the affected assistant ;
• the size of the mobile medicine-chest (small, medium or big).
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Lei Wang
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List of prescriptions by a service based on planning prescription
[error on order]
(assistant)
Validate
30 sec.
15%
(pharmacist)
Solve the problem
5~20 min.
[order ok]
(assistant)
List the med
1~2 min.
List of prescriptions by a service
(assistant)
Collect of medicines in a box
(transporter)
Transport the box to its service
Box of medicines box of medecines
20~30 min.
based on distance service-pharmacy
Medicines are not nominated but grouped by service in Hôpital Nord.
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
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Mobile nominated medicine-chest based on planning prescription
[error on order]
(assistant)
Validate
30 sec.
15%
(pharmacist)
Solve the problem
5~20 min.
[order ok]
(assistant)
Collection.
Supply of m.c
.
1~2 min.
(transporter)
Transport the m.c. to its service based on distance service-pharmacy
Mobile nominated
Medicine-chest
Medicines are nominated when collected in Hôpital Bellevue.
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
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Medication prescription
Exponential
(see table)
[error on order]
(assistant)
Validate
1 min.
15%
(pharmacist)
Solve the problem
5~20 min.
[order ok]
(assistant)
Collection
Packaging
1~2 min.
box of medecines
Medication prescription
(transporter)
Transport the box to its service based on distance service-pharmacy
Box of medicines
Arrivals
Monday
Tuesday
Wednesday
Thursday
Friday
PM
AM
PM
AM
PM
AM
PM
AM
PM
AM
Saturday AM
Total
Arg. of exp. law
9
6
18
26
11
19
158
16
11
19
7
16
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
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Entities : patients or nurse from a service
(assistant)
Validate prescription
Exponential
(see table)
1 min.
[error on order]
4%
(assistant)
Execution
[order ok] classic order : 4~5 min.
special order : 8~15 min.
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
Arrivals
Monday
Tuesday
Wednesday
Thursday
PM
AM
PM
Friday
AM
PM
Saturday AM
Total
AM
PM
AM
PM
AM
Number of patients
Number of nurses
8
3
2
91
11
6
18
3
7
12
9
12
27
9
9
16
23
21
187
7
35
4
21
15
19

Order sheet
Based on planning
(storekeeper)
Order analysis
1~6 min.
(storekeeper)
Prepare the order box : 1~2 min.
carriage : 30 min.
pallets : 12 min.
(storekeeper)
Pre-transport from store to pharmacy
Order sheet solutions
(transporter)
Transport to the service based on distance service-pharmacy solutions
This process describes the arrivals of medicines from external suppliers in H. Nord.
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
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• Presentation of the CHU-Saint-Étienne
• Goal of the study
• Modelling the flows of the current pharmacy department
• Simulation and first results
• Engineering the future pharmacy organisation (in progress)
• Conclusion and future work
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
21

• The current system was simulated under
Rockwell Arena® 8.0.
– Arena has proven itself efficient for healthcare simulation studies.
– Arena offers a large panel of analysis tools.
• Several approximations were made in order to convert the UML model to the flow chart model.
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
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
1. Process modelling
(transporter)
Transport to pharma.
(preparer)
Inventory of the m.c.
(preparer)
Collect of med.
Supply of m.c.
2. Data gathering
(transporter)
Transport to pharma.
(preparer)
Inventory of the m.c.
(preparer)
Collect of med.
Supply of m.c.
based on distance service-pharmacy small : 15~45 min.
med. : 20~40 min.
big : 35~50 min.
3. Simulation with Arena®
Create chariot_reserve matin
Assign chariot_reserve matin
0
Request transporteur pour chariot_reserve aller small : 25~35 min.
med. : 20~60 min.
big : 40~70 min.
Transport vers pharmacie pour chariot_reserve
(transporter)
Transport the m.c. to its service
(transporter)
Transport the m.c. to its service based on distance service-pharmacy
Station station_pharmacie
Assign date_entree chariot_reserve
Free transporteur pour chariot_reserve aller
27/07/2006
Seize preparateur
Delay inventaire chariot_reserve
Delay collecte chariot_reserve
Release preparateur
Request transporteur pour chariot_reserve retour
Transport vers service pour chariot_reserve
Xiaolan Xie - Vincent Augusto -
Lei Wang
23

• Length of stay of mobile medicine-chests in the pharmacy.
• Execution times of prescriptions.
• Workload of assistants.
• End of service time for each day.
 Useful to validate the simulation model.
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
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• Length of a replication : 5 weeks.
• Number of replications : 5.
• Common weekly planning without day-off.
• All resources are available during their shift (no illnesses or vacations).
25 27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang

Average
Simulation results
(min.)
Theorical
Results
(min.)
85.39
70.9
-
Half Width Minimum
Average
3.14
81.38
Maximum
Average
87.80
Minimum
Value
39.98
Maximum
Value
151.54
35 120
Theoric value + Waiting times ~= Simulation Value
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Lei Wang
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Average Half Width Minimum
Average
9.53
0.09
9.45
Regular order
(min.)
Emergency order
(min.)
16.00
Individual dispensary
(min.)
15.63
0.46
2.91
15.39
12.79
Maximum
Average
9.63
Minimum
Value
3.09
16.31
18.99
7.00
5.88
Maximum
Value
37.08
29.73
24.1
Like reality, emergency or individual medication dispensation are longer than regular medication.
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
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12
Monday
10
8
6
4 All nominated orders arrive by fax,
2 all assistants start at the same time.
0 h0
08 h3 h3
0
0
09 h0 h0
0
0
09 h3 h3
0
L
0
10 h0 h0
0
0
10 h3 h3
0
11
11 h0 h0
0
11 h3
0
0
12 h0 h0
0
0
12 h3
Activities of assistants begin when
L
08
L
08
L
09
L
09 10
L
10
L L
11
L
12
L
12
0
0
L
13 h0
13 h0
L
0
0
13 h3
13 h3
0
0
L
14 h0
14 h0
0
0
14
L
14 h3
0 h3
0
15 h0
L
15 h0
0
0
15
L
15 h3 h3
0
0
16 h0
L
16 h0
L
0
0
16 h3
16 h3
0
0
L
17 h0
17 h0
L
0
0
17 h3
0 h0
0
17 h3
0
18
L
18 h0
0
18 h3
0 mobile medication-chests arrive.
Tuesday
12
10
8
6
4
2
0
Ma
08 h0
0 0
Ma
08
8h h3
30
0 0
Ma
09
00
0 0
Ma
09
Ma
30
0 1
10
00
0 1
Ma
10
0h
30
0 1
Ma
11
1h
00
Ma
0 1
11
30
0 1
2h
00
0 1
Ma
12
Ma
12
2h
30
0 1
3h
00
0 1
Ma
13
Ma
13
3h
Ma
30
0 1
14
00
0 1
Ma
14
4h
30
0 1
Ma
15
5h h0
00
On tuesdays, mobile medication-chests are h0 h3 h0 h3 h0 h3 h0 h3 h0 h3 h0 h3 supplied in the morning and in the afternoon.
5h
30 h3
0 1
6h h0
00
0 1
Ma
16
Ma
16
6h h3
Ma
30
0 1
17
7h
00 h0
Ma
0 1
7h h3
30
0 1
8h
00
17
Ma
18 h0
0 1
8h
30
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
28

• Presentation of the CHU-Saint-Étienne
• Goal of the study
• Modelling the flows of the current pharmacy department
• Simulation and first results
• Engineering the future pharmacy organisation (in progress)
• Conclusion and future work
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
29

Modelling of the future pharmacy has been discussed with the pharmacy staff :
• All activities are grouped in the pharmacy of Hôpital Nord (no more pharmacy at
Bellevue).
• A large part of medical departments are moved from Bellevue to Nord.
• Flows are almost identical.
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
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• 7 main processes :
• Supply of mobile medicine-chests ;
• Regular supply of nominated medicines (like Bellevue) ;
• Emergency supply of nominated medicines ;
• Patient flow at the individual dispensary ;
• Medical solutions delivery ;
• Reception process ;
• Bellevue daily delivery process.
• 5 types of resources (same as before) :
• Pharmacists and interns;
• Assistants ;
• Storekeepers and transporters.
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
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• Is it OK to keep a medical solutions store in Bellevue ?
• External delivery of medical solutions :
– All solutions are delivered to Nord and then to
Bellevue ;
– Solutions for Nord are delivered to Nord, solutions for Bellevue are delivered to
Bellevue.
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
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• Organisation of medication transports
(planning, distances, mapping) :
– From and to medical departments in Nord ;
– between Nord and Bellevue.
• Organisation of the pharmacy staff shift in order to reduce idle times.
• Physical organisation of the dispensation hall in order to reduce dispensation times.
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
33

• Presentation of the CHU-Saint-Étienne
• Goal of the study
• Modelling the flows of the current pharmacy department
• Simulation and first results
• Engineering the future pharmacy organisation (in progress)
• Conclusion and future work
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
34

• UML has proven itself efficient for modelling a complex healthcare department.
• Migration towards Arena has been successfully made.
• The AS-IS system has been simulated, the model has been validated with the pharmacy staff.
27/07/2006 Xiaolan Xie - Vincent Augusto -
Lei Wang
35

• The same methdology is being used to model the future system.
• How the object oriented modelling can be fully used with simulation ?
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Lei Wang
36