Emergency Services Generalized Flexible Simulation Model

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Emergency Services Generalized Flexible
Simulation Model

• Paola FACCHIN
• Department of Paediatrics, University of Padova,
  Italy
• Giorgio ROMANIN JACUR
• Department of Management and Engineering,
  University of Padova, Italy
• EURO 2006

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EMERGENCY SERVICE 1

• Any emergency service
• is devoted to supply first aid to outpatients
• may alternatively serve
• a hospital or a group of hospitals,
• a department or a group of departments, according
  either to pathologies (e.g., obstetrics, surgery)
  or to types of patients (e.g., neonatology,
  paediatrics)

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EMERGENCY SERVICE 2

• Any emergency service is characterized by
• high variability of patient arrivals, depending
  on
• time (different intervals of the day, week, year)
• randomness (e.g., accidents, weather, epidemics)
• hard requirements for
• quick (sometimes immediate) response, also in
  case of congestion

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EMERGENCY SERVICE 3

• Any emergency service shall be correctly designed
  and managed for what concerns
• structures (major treatment, minor treatment
  rooms, waiting rooms, short term admission rooms,
  beds)
• technological resources (specifical instruments)
• human resources (doctors, nurses, engineers and
  related working rules, turns of duty, etc.)
• in order to supply a high quality service at
  minimum cost

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EMERGENCY SERVICE 4

• Discrete simulation may be a useful tool
• in the design phase, to find the right dimension
  of employed structures and resources
• in the working phase, to analyze, check and
  possibly adapt the system behaviour, both in
  normal and in exceptional conditions
• Discrete simulation requires to
• build up a model with the right level of detail
• implement it in a friendly language

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MAXI-EMERGENCY
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MAXI-EMERGENCY

• Emergency services are in general correctly
  dimensioned in order to react to normal request
  behaviour, related to users amount and type of
  life.A maxi-emergency arises whenever the
  amount of requests cannot be born by (structural,
  technological and human) resources at
  disposition as a consequence it is evidenced a
  brutal, even if temporary, insufficiency of
  immediately available rescue with respect to
  assistance requests that happens for instance
  because of severe road accidents involving many
  vehicles, fires, building collapses, earthquakes,
  spread of toxic gas, etc.

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PAPER CONTRIBUTION

• We build up a generalized flexible model, able to
  correctly describe many existing emergency
  services, by reduced adjusting on model structure
  and fundamental parameters
• We implement it by specialized software Micro
  Saint 3.2, which presents a good compromise
  between abstraction level and user friendliness
• We adapt such a model to describe both different
  actual types of emergency service and the
  behaviour of a service in special situations like
  a maxi-emergency

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EMERGENCY SERVICE GENERAL MODEL (LOW DETAIL)
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EMERGENCY SERVICE MODEL ARRIVALS
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• EMERGENCY SERVICE MODEL ARRIVALS
• Average arrivals
• random independent
• time dependent mean
• groupable in classes (to be defined now)
• Special arrivals (e.g., epidemics,
  extraordinary weather, maxi-emergency)
• randomness to be defined according to the
  particular case
• time dependency to be defined according to the
  particular case
• Pseudo arrivals
• change of orders (deterministically at every
  duty change)
• other (e.g., short term admission room
  inspections)

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EMERGENCY SERVICE ARRIVAL SELECTION (TRIAGE)
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• EMERGENCY SERVICE ARRIVAL SELECTION (TRIAGE)
• All arrivals are selected by the same unique
  filter (triage) which is ruled by specialized
  nurses
• The selection is based on the presented life
  parameters (predefined and universal) which
  determine the immediate life danger
• The selection assignes a colour code, according
  to immediate life danger, and related urgency
• red code, aid shall be immediate, any wait may
  cause death.
• yellow code, aid shall not be delayed more than
  some minutes, wait may increase severity.
• green code, aid may be delayed, a limited wait
  (tenth of minutes to two hours) is permitted
  without danger assistance cannot be supplied
  out of the hospital.
• white code, no life danger, any wait cannot cause
  damage assistance might be supplied out of the
  hospital (g. p.).

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• PATIENT ROUTING AND SUPPLIED SERVICES 1
• Patients of red code are assisted as follows
• (first look triage, to realize risky life
  parameters)
• first inspection (with preemption) and
  assistance/stabilization
• inner and/or outer examination(s)
• second inspection after examinations result
• home return / hospital admission / short term
  admission
• possible third inspection after short term
  admission and decision about home return /
  hospital admission
• (death may interrupt the sequence)

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• PATIENT ROUTING AND SUPPLIED SERVICES 2
• Patients of yellow code are assisted as follows
• first look triage, to realize risky life
  parameters
• second look triage, measurements (temperature,
  blood pressure, e.c.g., ), first assistance
  (e.g., bandage),
• personal data collecting
• first inspection (with priority on lower codes)
  and assistance/stabilization
• inner and/or outer examination(s)
• second inspection after examinations result
• home return / hospital admission / short term
  admission
• possible third inspection after short term
  admission and decision about home return /
  hospital admission

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• PATIENT ROUTING AND SUPPLIED SERVICES 3
• Patients of green code are assisted as follows
• first look triage
• second look triage, measurements (temperature,
  blood pressure, e.c.g., ), first assistance
  (e.g., bandage), personal data collecting
• first inspection (with priority on white codes)
  and assistance
• inner and/or outer examination(s)
• second inspection after examinations result
• home return / hospital admission / short term
  admission
• possible third inspection after short term
  admission and decision about home return /
  hospital admission

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• PATIENT ROUTING AND SUPPLIED SERVICES 4
• Patients of white code are assisted as follows
• first look triage
• second look triage, measurements (temperature,
  blood pressure, e.c.g., ), first assistance
  (e.g., bandage), personal data collecting
• first inspection and assistance
• home return

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PATIENT ROUTING AND SUPPLIED SERVICES 5 Inner
examinations e.g. urine, emato-chemical, made
inside the service Outer examinations e.g.
Orthopedical assistance, ... Cardiological
consulting, Radiographies, computer assisted
tomography, made either inside or outside the
service for which the patient may compete with
external orderly patients
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• PATIENT ROUTING AND SUPPLIED SERVICES
• According to the assigned colour code the patient
  is characterized by
• different routing
• different treatments
• different resources utilized
• different service time
• different priority and possible preemption in
  the queues, in particular for external services,
  if required

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PATIENT ROUTING AND SUPPLIED SERVICES
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• RESOURCES AT DISPOSITION
• STRUCTURES
• Major treatment room(s) - Minor treatment
  room(s)
• Short term admission room(s) - Waiting room(s)
• INSTRUMENTATION
• Special instruments
• DOCTORS
• duty chief responsible of the service
• (possible) assistant(s) on duty
• available within minutes (e.g., ten, twenty)
• working in external services
• NURSES
• triage nurses
• nurses on duty

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MODEL IMPLEMENTATION BY SW MICRO SAINT
Micro Saint is based on task network modelling
Network is easily built up by a CAD method
Main elements of networks are tasks, decisions
and queues
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MODEL IMPLEMENTATION BY SW MICRO
SAINT Example of task description
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MODEL IMPLEMENTATION BY SW MICRO
SAINT Example of description of a decision
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MODEL IMPLEMENTATION BY SW MICRO
SAINT Example of queue description
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MICRO SAINT MODEL NETWORK
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MICRO SAINT MODEL NETWORK ARRIVALS AND TRIAGE
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MICRO SAINT MODEL NETWORK EXTERNAL SERVICES
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MICRO SAINT MODEL NETWORK RED CODE
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MICRO SAINT MODEL NETWORK YELLOW CODE
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MICRO SAINT MODEL NETWORK GREEN CODE
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MICRO SAINT MODEL NETWORK WHITE CODE
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MICRO SAINT MODEL NETWORK DATA
DEFINITION ARRIVALS are ruled by all time
dependency parameters TRIAGE chooses different
routing for every patient group PATIENT ROUTING
defines access to resources and to external
services and related priorities (and
preemption) RESOURCES WHICH MAY BE SEIZED,
PRIORITY AND PREEMPTION are different for the
various patient groups EXTERNAL SERVICE
UTILIZATION are ruled by time dependency and
different priority for the patients HUMAN
RESOURCE PRESENCE is ruled by turns of duty ALL
ABOVE PARAMETERS ARE ADJUSTED IN ORDER TO
CORRECTLY DESCRIBE THE ACTUAL STUDIED SERVICE
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MICRO SAINT MODEL NETWORK SIMULATION RESULTS
ABOUT A QUEUE
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MICRO SAINT MODEL NETWORK SIMULATION
RESULTS Results reportflow times queues
parametersresource utilization They may be
supplied referred to single groups whole
performance
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EMERGENCY SERVICE GENERALIZED MODEL APPLICATIONS
IN SOME VENETO REGION HOSPITALS LARGE CITY
HOSPITALS San Bortolo Hospital in Vicenza
(90,000 patients per year) Borgo Trento Hospital
in Verona (100,000 patients per year) Borgo Roma
Hospital in Verona (60,000 patients per
year) SMALL CITY HOSPITALS, SERVING A LARGE AREA
INCLUDING MANY SMALL URBAN NUCLEI Hospitals in
Legnago, Adria, Valdagno, Arzignano (20,000
70,000 patients per year) ambulance
management SPECIALIZED HOSPITAL, Paediatric
Department at Padova University (20,000 patients
per year)
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EMERGENCY SERVICE GENERALIZED MODEL APPLICATIONS
IN SOME VENETO REGION HOSPITALS URGENT
ASSISTANCE CENTRES, SUPPORTED BY MORE HOSPITALS,
in Lonigo and in Montecchio Maggiore MAXI-EMERGE
NCY at San Bortolo Hospital in Vicenza and
Arzignano EMERGENCY SERVICE HOSPITAL
DEPARTMENT INTERRELATIONS, at San Bortolo
Hospital in Vicenza, at Arzignano Hospital, at
Lonigo First Assistance Centre
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Borgo Roma E. S. Organization
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Emergency Service model of Verona Borgo Trento
Hospital
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Legnago Hospital Emergency Service task network
model
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West Vicenza Health Unit Area
ES VALDAGNO

ES ARZIGNANO
USC MONTECCHIO M.
USC LONIGO
4
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Lonigo Urgent Assistance Centre Task Network
RITORNO
SOSTITUTO
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Vicenza E. S. for maxi-emergency

• area rossa
• area gialla
•  area verde
• area bianca
• area triage maxi-emergenza
• area triage interno
• area nera
• area dimessi
• area pubbliche relazioni

Vengono allestite
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IL MODELLO
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CONCLUSIONS

• The presented model has been tested on many
  different actual services
• It is sufficiently detailed and extremely
  flexible, therefore it may be easily employed to
  simulate different emergency services
• It is a useful managing instrument to improve the
  service performance, as it permits to detect all
  possible critical points and consequently to
  suggest suitable correcting actions

Facchin P., Romanin Jacur G. "Emergency
Service a Generalised Flexible Simulation
Model, n Modeling and Simulation 2003, B. Di
Martino, L.T. Yang, C. Bobeanu, (vol. 1). ISBN
90-77381-04-X. GHENT Eurosis-Eti (BELGIUM),
2003, pp. 541-545.
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OPEN PROBLEMS

• Better analysis of interrelations
• between Emergency Service and other departments
  of the hospital (for consulting, external
  examinations and admissions)
• Between Emergency Service and ambulance
  transportation service