ADHB Orderly Simulation Project

Objectives

-Use historical data out of the INFRA transit booking system to develop a simulation of in-patient transit between Radilogy and other departments with the assistance of orderlies.

-Once the simulation has been developed and validated, use it to explore different scheduling scenarios.

Expected outcomes

Summary of ADHB Meeting 25/11/10

-Ethics approval required as particular patients may be identified from the data

-Radiology Sites-Level 5 (main site), Level 2 (Emergency), Level 9 (Maternity)

-Focussed on inpatients, those already admitted. These patients are moved to/from radiology. This could be from any ward/theater/critical care.

-Two orderly teams. We are focussing on the non-maternity team.

-Transfers are scheduled using an online booking system by the MRT imagers.

-Bookings may not be communicated correctly, but we will assume they are for the purposes of this project

-The booking system is known as INFRA

-The time taken for the radiography procedures is relatively reliable, the main variability is in the set-up times for different patients, which depends on the condition of the patient.

-Approximately 2/3 of patients can be taken by orderlies on their own, and around 1/4 or more require the presence of a transit nurse due to the condition of the patient.

-Specific nurses are assigned to be transit nurses for a particular shift. The ratio of transit nurses to orderlies is around 1:4.

-The target is for a patient to reach their destination within 15 minutes of the scheduled time.

-As a measure of the arrival time, we use the time the orderly calls the dispatcher to report the job completed-assume that this is the arrival time, no delay from orderly.

-Dispatcher will schedule MRIs in preference to X-rays

-Return+transit jobs are handled by the same scheduler

-Need to do return jobs-if too many people are left waiting then beds fill up and people cannot be transferred into Radiology.

-Possible thing to explore with simulation: what happens if the orderly stays with the patient throughout the radiology procedure

-First step in simulation-use historical data.

Discrete Event Orderly Simulation

1. Daily plan/schedule created?

Event: Radiologist books an appointment for a patient

Triggers: Next booking event (if random?)

For each booking: Appointment booked is scheduled into list

by the dispatcher (use list container to hold sequence of transits?)

Event: Time of scheduled transit reached

Check if any free orderlies (Orderly class with isfree attribute)

If not, wait until an orderly is free

When there is a free orderly, the orderly travels to the patient

(Record current location of orderly in orderly class)

The orderly then takes the patient to their destination, and is freed

Use stochasticity for travel times

Non-event classes:

Orderly class:

Attribute isfree-stores whether the orderly is free

Attribute currentLocation-stores the current location of the orderly

Booking class:

Attribute-booking time