Emergency room use at " SAVE - ME!! "Hospital peaks on Saturday nights during the period from 7:00 P.M.to 2:00 A.M. Historically, the hospital has provided space for five stations (examining rooms) for non emergency cases and two stations for emergency cases during that period. Non emergency patients are examined on a first - come, first - served basis, and emergency cases are treated on a most - serious, first - served basis, after a triage nurse has screened all cases. An area competitor hospital recently announced discontinuation of emergency services within six months. " SAVE - ME!! "estimates that current arrival patterns during the 7:00 P.M. - 2:00 A.M. period would increase by one - third for non emergency cases and would double for emergency cases. The hospital wants to know how additional resources in the ER might reduce congestion and waiting time, as well as the overall cost of operations for non emergency and for emergency patients. The past year 's operating data were gathered from the information systems; they included records of arrival and service times. Preliminary examination of the data revealed little seasonal variation in ER use for that year, and ER personnel stated that their protocols and procedures had remained relatively constant since the reorganization of the ER two years ago. The arrival pattern of patients, tabulated for twenty Saturday nights (total of one hundred hours), showed that 900 non emergency and 150 emergency patients came to the ER during that time. The arrival pattern approximates a Poisson distribution. After a lengthy time - motion study, the average service time was found to be thirty minutes per non emergency and seventy - five minutes per emergency patient. A separate study conducted by the fi nance/accounting department provided estimates for relevant costs as shown in Table
Cost type\Patient Type NonEmergency Emergency
Busy server cost/hr 100 200
Idle server cost/hr 450 800
Customer waiting cost/hr 200 400
Customer being served cost/hr 100 300
a. Using Excel queuing template, analyze both the emergency and the non emergency capacity requirements for current conditions and for six months later, and fill in the Performance Evaluation Table.
b. Recommend the number of examining rooms for current and the future conditions on the basis of the above performance - evaluation statistics. Source: Screen shots reprinted by permission from Microsoft. Figure 14.14. Capacity Analysis.
