Browsing by Author "Lang, Eddy S."

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    Improving Emergency Department Efficiency: A Study of Physician Scheduling Strategies to Reduce Patient Wait Times
    (2024-06-17) Ganjouhaghighi, Negar; Bijvank, Marco; Sabouri Bagh Abbas, Alireza; Alp, Osman; da Silveria, Giovani Jose Caetano; Lang, Eddy S.; Lahrichi, Nadia; Weinhardt, Justin
    Prolonged wait times and overcrowding in emergency departments (EDs) represent significant national challenges in Canada. Within this thesis, I examine three distinct approaches aimed at assisting managers, decision-makers, and schedulers within EDs in addressing these pressing issues. Emergency departments serve as the initial point of contact for patients within the healthcare system, constituting a crucial yet interconnected component of healthcare provision. This study narrows its focus to the aspect of physician scheduling within EDs, recognizing its pivotal role in mitigating wait times and improving efficiency. The initial focus of my investigation lies in optimizing physician schedules within EDs to align with the fluctuating supply and demand dynamics. Extensive literature review and our own dataset reveal the variable productivity levels among physicians in these settings. In this thesis, productivity primarily refers to the number of new patients seen (or treated) by a physician per hour of their shift—a crucial metric in our pursuit of reducing patient wait times. Acknowledging this variability, I first delve into incorporating physician productivity (measured in Patients Per Hour, or PPH rate) into a staffing and shift scheduling problem for physicians. Numerical results show that significant improvements can be obtained in terms of average wait times for patients if we consider the variable productivity if physicians in the staffing and shift scheduling problem. Despite the optimization of schedules, the inherent stochastic nature of ED operations implies occasions where patient volumes exceed expectations, which lead to increased wait times. In response to these fluctuations, in the second and third studies, I propose and assess two distinct strategies aimed at managing ED crowding levels. Particularly, I derive optimal policies for EDs on when and how to extend physicians' shifts or call in physicians in response to a surge in demand. Using the simulation model to evaluate these strategies, I show the effectiveness of having flexibility in physicians schedules in reducing the average wait time of patients.
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    Optimally Linking Prehospital and Health System Data: The Association between Emergency Medical Services Offload Time, Response Time and Mortality
    (2020-01-14) Blanchard, Ian; Doig, Christopher James; Lang, Eddy S.; Dean, Stafford R.; Hagel, Brent Edward; Niven, Daniel J.; Williamson, Tyler S.
    INTRODUCTION: Delays in offloading Emergency Medical Services (EMS) patients in the hospital may impact timely response to emergencies, but no published studies are available. Little research has been conducted on the potential for bias when EMS data are linked to health system outcome and on the optimal EMS response time for survival of critically injured or ill patients. METHODS: Three years of EMS data from a large urban system were used to create hourly estimates of median hospital time and response time, and linked to health system outcome. Multivariable modelling and descriptive statistics were used to: 1. Explore the association between paramedic hospital time and response time while controlling for the effects of system volume, time of day, and season; 2. Describe the linkage rate between the standard strategy and one designed to optimize linkage; and 3. Explore the association between response time and mortality in critically injured or ill patients who did not experience an out-of-hospital cardiac arrest while controlling for age and sex. RESULTS: Depending on the time of day, there was between a one and three minute increase in predicted median response time when the system was experiencing a median hospital time of 90 minutes, during the winter in heavy system volume, compared to a 30 minute median hospital time, during the summer in light system volume. The optimized strategy increased the linkage rate from 88% to 97.1%, and reduced linkage failure in key clinical sub-groups. There was no significant association between response time and mortality except in one secondary analysis subgroup, which suggested longer response decreased mortality. CONCLUSIONS: There is an association between EMS hospital time and response time, but the relationship is complex and influenced by system level factors such as time of day, volume and season. An optimized strategy for linking EMS data to health system outcome improved the linkage rate and reduced the potential for bias. No consistent association between response time and mortality could be demonstrated. These analyses underscore the importance of research quality linked EMS data in the development of knowledge for EMS and paramedic practice.
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    Use of prehospital ultrasound in North America: a survey of emergency medical services medical directors
    (BioMed Central, 2014-03-01) Taylor, John; McLaughlin, Kyle; McRae, Andrew; Lang, Eddy S.; Anton, Andrew