Using Queuing Theory and Simulation Model to Optimize Hospital Pharmacy Performance

Abstract

Background:Hospital pharmacy is responsible for controlling and monitoring the medication use process and ensures the timely access to safe, effective and economical use of drugs and medicines for patients and hospital staff.Objectives:This study aimed to optimize the management of studied outpatient pharmacy by developing suitable queuing theory and simulation technique.Patients and Methods:A descriptive-analytical study conducted in a military hospital in Iran, Tehran in 2013. A sample of 220 patients referred to the outpatient pharmacy of the hospital in two shifts, morning and evening, was selected to collect the necessary data to determine the arrival rate, service rate, and other data needed to calculate the patients flow and queuing network performance variables. After the initial analysis of collected data using the software SPSS 18, the pharmacy queuing network performance indicators were calculated for both shifts. Then, based on collected data and to provide appropriate solutions, the queuing system of current situation for both shifts was modeled and simulated using the software ARENA 12 and 4 scenarios were explored.Results:Results showed that the queue characteristics of the studied pharmacy during the situation analysis were very undesirable in both morning and evening shifts. The average numbers of patients in the pharmacy were 19.21 and 14.66 in the morning and evening, respectively. The average times spent in the system by clients were 39 minutes in the morning and 35 minutes in the evening. The system utilization in the morning and evening were, respectively, 25% and 21%. The simulation results showed that reducing the staff in the morning from 2 to 1 in the receiving prescriptions stage didn't change the queue performance indicators. Increasing one staff in filling prescription drugs could cause a decrease of 10 persons in the average queue length and 18 minutes and 14 seconds in the average waiting time. On the other hand, simulation results showed that in the evening, decreasing the staff from 2 to 1 in the delivery of prescription drugs, changed the queue performance indicators very little. Increasing a staff to fill prescription drugs could cause a decrease of 5 persons in the average queue length and 8 minutes and 44 seconds in the average waiting time.Conclusions:The patients' waiting times and the number of patients waiting to receive services in both shifts could be reduced by using multitasking persons and reallocating them to the time-consuming stage of filling prescriptions, using queuing theory and simulation techniques.

Analysis of Waiting Time for Filing Prescriptions in Hospital Pharmacy

“…9 Discipline in the service should also be implemented. Patients who come first are patients who are served first, unless for patients who have more serious medical conditions 10,11 Conclusion Several strategies should be performed to decrease waiting time, e.g., the use of computer-based queuing system and the imporvement of the quality and quantity of human resources in the hospital pharmacy, Acknowledgement None. …”

Simulation of a Queuing System of a Post Office in Anylogic Software

“…An event represents a change in the state of the system at a time. There are two event types in simpler event-based simulation models arrival of customer and an end of service [10][11][12][13]. employee works with an information system.…”

“…Therefore it is advisable to use a simulation method to get the system model closer to the real system, as much as possible. Contribution of the simulation method is in the ability of capturing the dynamic side of the system and complicated probabilistic relationships [10][11][12][13][14][15].…”

Queuing Management Simulation Using Lean in Pharmacy Department of Hermina Yogya Hospital: Exploiting the Potential of Reducing Cycle Time

“…The pattern of prescription arrival, the percentage of pharmacy department staff, work order, and interactions between fellow pharmacy employees as well as between pharmacy employees and patients often inhibits efficiency [3], [4]. The decrease in efficiency is reflected in the length of the queue for drug purchasing, which in turn causes dissatisfaction of the patients [5] - [7]. A number of studies confirm how the service in the pharmacy department affects the overall patient satisfaction on hospital services [3], [8], [9].…”