A Simulation Study of Outpatient Surgery Clinic with Stochastic Patient Re-Entrance

This study investigates how the variability of different stochastic elements affects the performance of operations at a Mohs Micrographic Surgery (MMS) clinic. MMS is a popular procedure to treat non-melanoma skin cancers. In MMS, the surgeon performs skin layer excisions on the patient one at a time, and the removed layer is then examined. If cancerous cells remain during examination, another excision will be conducted; otherwise the patient goes through wound repair before being discharged. Such repetitive excisions of thin layers lead to low re-occurrence rates and impressive post-surgery cosmetic results, but it requires uncertain amount of same-day surgeries which may lead to long patient waiting times and clinic overtime. We develop a simulation model to study the operational performance of an MMS clinic with a given appointment schedule used in practice. Our study reveals how the waiting time and clinic overtime is affected by different stochastic factors.