OPTIMAL PATIENT SERVICE DESIGN IN A RADIODIAGNOSTIC MEDICAL FACILITY
C. O. Arimie*1 and E. H. Etuk2
1Department of Radiology, University of Port Harcourt Teaching Hospital, Port Harcourt
2Department of Mathematics/Computer Science, Rivers State University of Science and Technology, Port Harcourt
E-mail: codarimie@yahoo.com
ABSTRACT
Queuing theory is a powerful quantitative tool that enables healthcare facilities to uncork chronic bottlenecks in the flow of patients but, healthcare systems have some peculiar features that impact on their modeling in the framework of the queuing theory. To redesign the radiodiagnostic facility of the University of Port Harcourt Teaching Hospital (U.P.T.H) using queuing theory, and to assess the impact of the time lag between patients arrival and the commencement of imaging procedures, occasioned by absences and lateness to work by healthcare personnel and other logistic problems, on the operating characteristics and the optimality criterion. The patients’ service schedule was altered so that only outpatients were allowed service during the peak period of 8.00 a.m. to 1.00 p.m. daily. Arrival and service rates data were collected and used to fit the Poisson model. Prior to this time, data were not available on arrival rates and service times. The steady-state probabilities, measures of performance, the probability of an arrival joining the queue, and the joining rate were calculated. The rescheduling revealed that the system was M/M/c/GD/¥ /¥ as the patients’ arrival and service rates data collected fitted the Poisson model. We discovered an improvement in the various measures of performance especially, the throughput of outpatients although, the time lag between arrival and commencement of service increased the queue length and waiting time. Patient service in the radiodiagnostic facility can be optimized using the queuing theory but, service must commence as the patients arrive in order to achieve optimal performance. Secondly, performance of a queuing system may just be specified in terms of probabilities.
Key words: Queuing, Optimization, Markov chain, Radiodiagnostic facility, Medical.