A simulation study of the winter bed crisis.

The winter bed crisis is a cyclical phenomenon which appears in British hospitals every year, two or three weeks after Christmas. The crisis is usually attributed to factors such as the bad weather, influenza, older people, geriatricians, lack of cash or nurse shortages. However, a possible alternative explanation could be that beds within the hospital are blocked because of lack of social services for discharge of hospital patients during the Christmas period. Adopting this explanation of why the bed crisis occurs, the problem was considered as a queuing system and discrete event simulation was employed to evaluate the model numerically. The model shows that stopping discharges of rehabilitating patients for 21 days accompanied by a cessation of planned patients for 14 days precipitate a bed crisis when the planned admissions recommence. The extensive "what-if" capabilities of such models could be proved to be crucial to the designing and implementation of possible solutions to the problem.

Evaluating the costs of alternative options for dementia services.

In the next decade the number of demented people is likely to increase. This has a financial impact on the resources allocated for health and social care. Classical methodologies for dealing with dementia include the historic model that has been criticised for its poor co-ordination between general practitioners, psychiatrists, social workers and the treatment services, and the needs-based approach that, although it involves a co-ordinating needs manager, does not prevent leapfrogging of patients. In order to overcome these problems we propose an annual screening of patients to take place in the needs-based models and compare this with a more sophisticated model in which after being screened patients are investigated for potential drug treatment. We also consider mix intervals for under 75 and over 75. Decision analysis is used to assess the different screening options. Assuming a 20% reduction by treatment of the cost of care we find optimal the investigation/treatment of all patients after screening. Sensitivity analysis shows that even an 8.5% reduction would make the needs-based models non-optimal.

A simulation modelling approach to evaluating length of stay, occupancy, emptiness and bed blocking in a hospital geriatric department.

The flow of patients through geriatric hospitals has been previously described in terms of acute (short-stay), rehabilitation (medium-stay), and long-stay states where the bed occupancy at a census point is modelled by a mixed exponential model using BOMPS (Bed Occupancy Modelling and Planning System). In this a patient is initially admitted to acute care. The majority of the patients are discharged within a few days into their own homes or through death. The rest are converted into medium-stay patients where they could stay for a few months and thereafter either leave the system or move on to a long-stay compartment where they could stay until they die. The model forecasts the average length of stay as well as the average number of patients in each state. The average length of stay in the acute compartment is artificially high if some would-be long-term patients are kept waiting in the short-stay compartment until beds become available in long-stay (residential and nursing homes). In this paper we consider the problem as a queueing system to assess the effect of blockage on the flow of patients in geriatric departments. What-if analysis is used to allow a greater understanding of bed requirements and effective utilisation of resources.