Yann Ferrand

Building Cyclic Schedules for Emergency Department Physicians

Physicians at a branch of the emergency department at Cincinnati Childrens Hospital Medical Center complained that their schedules were too erratic because of the multitude of operating requirements, regulatory constraints, physician preferences, and holiday requests. We addressed this issue by using integer programming to build cyclic schedules that can be repeated throughout the year. These schedules are flexible enough to handle incorporating holidays, work assignments, and vacation requests ex post. After we rolled out the calendar-year-based cyclic schedule, we captured statistics to assess the viability and the quality of the yearly schedule generated. Surveys of the physicians and the scheduler after implementation showed that the new schedule provides predictability and well-balanced work patterns.

Comparing two operating-room-allocation policies for elective and emergency surgeries

When organizing the operating theatre and scheduling surgeries, hospitals face a trade-off between the need to be responsive to emergency cases and to conduct scheduled elective surgeries efficiently. We develop a simulation model to compare a flexible and a focused resource-allocation policy. We evaluate these two policies on patient and provider outcome measures, including patient wait time and physician overtime. We find that the focused policy results in lower elective wait time and lower overtime, which leads to the conclusion that electives benefit more from the elimination of emergency disruptions than what they lose from the reduced access to operating rooms. Emergency patient wait time, however, increases significantly as we shift from the flexible to the focused policy. The sensitivity analysis showed that average emergency wait time can decrease as the processing time variability increases. The trade-off between efficiency and responsiveness calls for additional research on other operating-room-allocation policies.

Managing operating room efficiency and responsiveness for emergency and elective surgeries—A literature survey

This paper provides a review and classification of the state of research on the question of how a hospital can best utilize its operating rooms (ORs) to balance efficiency and responsiveness when performing surgeries on scheduled electives and high-priority emergencies. We first provide an overview of the specific research questions and conclusions in the literature, as well as a synthesis of the different types of approaches. Then we classify these approaches by methodology and performance measures considered. We also extend the review to other application domains that face a similar question, and highlight similarities and differences to identify potential learning points that apply to the surgery setting. We anticipate this survey highlights the need for future quantitative research that improves the balance of efficiency and responsiveness in the OR.

Partially Flexible Operating Rooms for Elective and Emergency Surgeries

In hospitals, the management of operating rooms faces a trade-off between the need to be responsive to emergency surgeries and to conduct scheduled elective surgeries efficiently. Operating rooms can be configured as flexible and handle both electives and emergencies, or as dedicated to focus on either electives or emergencies. With flexible rooms, the prioritization of emergencies over scheduled electives can lead to schedule disruptions. Focused rooms can lead to imbalances between capacity and surgery workload. Whereas hospital administrators typically handle this trade-off by employing either flexible rooms (complete flexibility) or dedicated rooms (complete focus), we investigate whether a combination of flexible and dedicated rooms (partial flexibility) could be a preferable alternative. The ensuing question is what is the right combination of flexible and dedicated rooms? A versatile simulation model is developed to evaluate different resource allocation policies under various environmental parameters and performance metrics, including patient wait time, staff overtime, and operating room utilization. The main result is that partial flexibility configurations outperform both complete flexibility and complete focus policies by providing solutions with improved values of expected wait time for both emergency and elective patients.

Biotechnology in Cincinnati

This research, conducted via interviews at 32 biotechnology firms, which provide rare information on actual firm interactions, elucidates the factors that influence the location and growth of the biotechnology sector in a typical American metropolitan area. Results indicate that most of the biotechnology firms within the Cincinnati region are there because of entrepreneurial ties with universities and research hospitals in the area, not because the region has specific advantages for biotechnology firms compared to other metropolitan areas of similar size. The authors find that interfirm linkages range from extremely weak to nonexistent. No specialized labor force exists to support biotechnology firms, nor are there specialized infrastructure and business services. No biotechnology-dedicated government office exists. In summary, the authors see more colocation than interactive clustering of biotechnology firms, implying that economic development efforts to enhance interfirm linkages are likely to be less effective than support for hospital and university research and education.

Comparative Effectiveness of Tacrolimus-Based Steroid Sparing versus Steroid Maintenance Regimens in Kidney Transplantation: Results from Discrete Event Simulation

Background. Corticosteroids used as immunosuppressants to prevent acute rejection (AR) and graft loss (GL) following kidney transplantation are associated with serious cardiovascular and other adverse events. Evidence from short-term randomized controlled trials suggests that many patients on a tacrolimus-based immunosuppressant regimen can withdraw from steroids without increased AR or GL risk. Objectives. To measure the long-term tradeoff between GL and adverse events for a heterogeneous-risk population and determine the optimal timing of steroid withdrawal. Methods. A discrete event simulation was developed including, as events, AR, GL, myocardial infarction (MI), stroke, cytomegalovirus, and new onset diabetes mellitus (NODM), among others. Data from the United States Renal Data System were used to estimate event-specific parametric regressions, which accounted for steroid-sparing regimen (avoidance, early 7-d withdrawal, 6-mo withdrawal, 12-mo withdrawal, and maintenance) as well as patients’ demographics, immunologic risks, and comorbidities. Regression-equation results were used to derive individual time-to-event Weibull distributions, used, in turn, to simulate the course of patients over 20 y. Results. Patients on steroid avoidance or an early-withdrawal regimen were more likely to experience AR (45.9% to 55.0% v. 33.6%, P < 0.05) and GL (51.5% to 68.8% v. 37.8%, P < 0.05) compared to patients on steroid maintenance. Patients in 6-mo and 12-mo steroid withdrawal groups were less likely to experience MI (11.1% v. 13.3%, P < 0.05), NODM (30.7% to 34.4% v. 37.7%, P < 0.05), and cardiac death (29.9% to 30.5% v. 32.4%, P < 0.05), compared to steroid maintenance. Conclusions. Strategies of 6- and 12-mo steroid withdrawal post-kidney transplantation are expected to reduce the rates of adverse cardiovascular events and other outcomes with no worsening of AR or GL rates compared with steroid maintenance.

Simulation-Based Design of ED Operations with Care Streams to Optimize Care Delivery and Reduce Length of Stay in the Emergency Department

Faced with the opportunity to significantly deviate from classic operations, a new emergency department (ED) and novel strategy for patient care delivery were simultaneously initiated with the aid of model-based simulation. To answer the design and implementation questions, a traditional strategy for construction of discrete-eventmodel simulation was employed to define ED operations for a newly constructed facility in terms of workflow, variables, resources, structure, process logic and associated assumptions. Benefits were achieved before, during and after implementation of an unprecedented operations strategy—i.e., the organization of the ED care delivery around four care streams: Critical, Diagnostic, Therapeutic and Fast Track. Prior to opening, it shed light on the range of context variables where benefits might be anticipated, and it facilitated staff understanding and judgements of performance. Two years after opening, the operations data is compared to the simulation with encouraging results that shed light on where to continue pursuit of improvement.

The Influence of Traffic, Area Location, and Other Factors on Operating Room Microbial Load

OBJECTIVE To determine how the movement of patients, equipment, materials, staff, and door openings within the operating room (OR) affect microbial loads at various locations within the OR. DESIGN Observation and sampling study. SETTING Academic health center, public hospital. METHODS We first analyzed 27 videotaped procedures to determine the areas in the OR with high and low numbers of people in transit. We then placed air samplers and settle plates in representative locations during 21 procedures in 4 different ORs during 2 different seasons of the year to measure microbial load in colony-forming units (CFU). The temperature and humidity, number of door openings, physical movement, and the number of people in the OR were measured for each procedure. Statistical analysis was conducted using hierarchical regression. RESULTS The microbial load was affected by the time of year that the samples were taken. Both microbial load measured by the air samplers and by settle plates in 1 area of the OR was correlated with the physical movement of people in the same area but not with the number of door openings and the number of people in the OR. CONCLUSIONS Movement in the OR is correlated with the microbial load. Establishing operational guidelines or developing OR layouts that focus on minimizing movement by incorporating desirable internal storage points and workstations can potentially reduce microbial load, thereby potentially reducing surgical site infection risk. Infect Control Hosp Epidemiol 2018;39:391-397.