Purpose This case1 provides the opportunity to apply simulation models to assess operating practices

Purpose This case1 provides the opportunity to apply simulation models to assess operating practices in an orthopaedic surgery application at Hipkins Hospital. Suggestions for improvements in the rate of surgeries and average patient flow time are sought. Assignment Surgeons at the Department of Orthopaedic Surgery at Hipkins Hospital currently each complete an average of four to five total hip (THA) or total knee (TKA) replacement (arthroplasty) surgeries per day. While Hipkins is a teaching hospital, with training commitments that may slow the rate of surgeries, it is important to note that surgeons in private practice typically finish an average of approximately eight similar surgeries in a day. The Director of Orthopaedic Surgery at Hipkins Hospital is therefore seeking suggestions for operational improvements that will: • Increase the number of surgeries an orthopaedic surgeon can finish in a 10-hour day, to six (or more), and • Reduce patient flow time. Reduced patient flowtime may lead to an increase in the number of surgeries that can be completed in a day, but likely provides the added benefits of reducing stress and improving the well-being of patients and their family members. The flow time of a patient is measured from the time of their arrival to the completion of their surgery. Background Information on Knee (TKA) and Hip (THA) Arthroplasty Surgical Procedures The American Joint Replacement Registry (AJRR), the cornerstone of the American Academy of Orthopaedic Surgeons (AAOS) Registry Program, released its 2021 Annual Report on hip and knee arthroplasty procedural trends, and patient outcomes at the American Association of Hip and Knee Surgeons’ (AAHKS) 2021 Annual Meeting. Despite the disruption to the delivery of joint replacement care during the initial impact of the COVID-19 pandemic (March through May 2020), procedures rebounded to historic averages by June 2020. Even with the temporary decline in procedures, the report demonstrates an overall cumulative procedural volume growth of 18.3% compared to the previous year. For both THA (Total Hip Arthroplasty) and TKA (Total Knee Arthroplasty), postoperative length of stay in the AJRR cohort has continued to decrease with a substantial decrease in non-home discharge (representing <6% of all discharges). The utilization of general anesthesia has declined for both THA and TKA, with an increase in regional and neuraxial anesthesia. After adjustment in multivariate models, higher surgeon volume was associated with a lower risk of complications, lower rates of readmission and reoperation, shorter length of hospital stay, and a higher likelihood of being discharged home. Higher hospital volume was associated with a lower risk of mortality, lower risk of readmission, and a higher likelihood of being discharged home. The impact of process standardization was substantial; maximizing adherence to evidence-based processes of care resulted in improved clinical outcomes and shorter length of hospital stay, independent of hospital or surgeon procedure volume. Although surgeon and hospital procedure volumes are unquestionably correlated with patient outcomes in total joint arthroplasty, process standardization is also strongly associated with improved quality and efficiency of care. The exact relationship between individual processes of care and patient outcomes has not been established; however, findings suggest that process standardization could help providers optimize quality and efficiency in total joint arthroplasty, independent of hospital or surgeon volume2 . Many studies have shown that longer operative times (OTs) are associated with an increased frequency of postoperative complications. Patient Demographics The 2021 AJRR Annual Report reported on 2,244,587 primary and revision hip and knee arthroplasties between 2012 and 2020. The majority of the surgeries were primary TKA (54.5%) and primary THA (38.6%). Female patients represented 58.5% of all procedures while male patients represented 38.6% of cases. THA patients were on average 66.1 years old, whereas TKA patients were on average 67 years old. Although race was not recorded in 15.8% of instances, most patients were Caucasian (75.6%). The relationship between patient characteristics such as demographics and comorbidities and the risk of revision after initial TKA and THA has been a focus of AJRR's research. The 2021 Annual Report used age by decade for those aged 65 years and older to further the investigate risk of revisions based on age. A trend was identified suggesting older age was associated with increased cumulative percent revision. This trend was statistically significant comparing male patients older than 84 years to those aged 65-74 years and comparing female patients aged 75-84 years to those aged 65-74 years. There is also evidence (see Table 1 below) that morbidly obese patients, those with Body Mass Index (BMI) greater than 40 Kg/m2 , require longer operating times compared with normal weight, overweight, and obese patient categories. There are also operationally significant increases in operating times with increases in BMI. The hospital operates two groups of two operating rooms (ORs). Six patients are scheduled each day for knee or hip replacements (arthroplasties) in each OR group, starting at 7.30am, and with an interarrival time of 90 minutes. The 10 hour (600 minutes) work day ends at 5.30pm. Many of the patients who are scheduled for surgery at the end of a work day have to be bumped to the next day, creating significant dissatisfaction and disruption of their arrangements. Statistics of the surgery (procedure) time are shown in Table 2 for five body mass index (BMI) categories. The process is as follows. Patients are registered, receive preoperative preparation and anaesthesia, and then their procedure. After a period of recovery, most patients are able to return home the same day. Most of the rest spend the night in the hospital and then return home the next day. There are four ORs at Hipkins Hospital, divided into two OR groups - A and B. Two staff members work in a registrar pool to register the patients in both OR groups. Each OR group has a dedicated anaesthesiologist and orthopaedic surgeon, who alternate between the two ORs assigned to them, to maximize patient flow. Surgeries cannot commence until environmental services (EVS) has cleaned and restocked an OR with the appropriate instrumentation. Two EVS staff members work in the EVS pool to clean and restock all four ORs. An AnyLogic model of the process is shown in Figure 5. Recent process duration statistics for registration, delivery of anaesthesia, surgery, and housekeeping are shown in Table 3. The procedure mean and standard deviation are computed using the weighted means and variances from Table 2. Are improvements in the workflow possible that could reduce patient flow times and increase the number of hip and knee replacement surgeries that can be completed in a 10-hour day? Using simulation models to estimate and contrast the surgery rate and average patient flow time, consider improvements using the following four lenses: 1. Does utilization matter? For example, should some registrars, anaesthesiologists, surgeons, and/or EVS staff members be hired or fired? Should the number of ORs be increased? 2. Does pooling matter? For example, should the surgeons be pooled (so that the two surgeons can work in all four ORs)? Should the anaesthesiologists be pooled? 3. Does variance hurt? For example, would reductions of say 10 or 20% in the variance of durations make any real difference? 4. Does psychology matter? Is the difference between actual and perceived waiting time important in this application for the patients, their family members, and hospital staff? How can perceived waiting be reduced? Note that some patients whose surgeries are bumped to the next day perceive that night to be waiting time. Additionally, address the following questions posed by the Director: 1. What type of process is the surgery workflow (e.g. job shop, batch, line flow, continuous flow)? 2. What is the flow time of the workflow before and after your proposed improvements? 3. Where are you seeing bottlenecks? 4. Are any of your proposed changes in conflict with fostering diversity, equity, and inclusion? Bozic et al (2010) and Healy (1995) point to the benefits of standardization. Khanuja (2023) does not believe that robotics will meaningfully reduce procedure times, with the possible exception of patients in the morbidly obese BMI category. Khanuja et al (2019) and Wang et al (2013) emphasize the importance of BMI for surgery efficiency. Other authors (e.g., von Eiffe et al (2019)) have investigated TKA and FHA process improvements. Tools Discrete event simulation models are available for the analysis: AnyLogic model and HOWTO video playlist. The AnyLogic model is shown in Figure 5.

******CLICK ORDER NOW BELOW AND OUR WRITERS WILL WRITE AN ANSWER TO THIS ASSIGNMENT OR ANY OTHER ASSIGNMENT, DISCUSSION, ESSAY, HOMEWORK OR QUESTION YOU MAY HAVE. OUR PAPERS ARE PLAGIARISM FREE*******."