This study presents a methodology that integrates discrete event simulation (DES) with design of experiments (DoE) to maximise operational efficiency, with a focus on sustainability and resilience in the context of industry 5.0. Thus, a DES model is developed in FlexSim 2025 that represents the areas of interest. In addition, to parameterise the process times, 60 observations are recorded to adjust the probability distributions with the Fitted Distribution tool. Thus, a DoE based on a 23 full factorial design with three factors is implemented: doctors, nurses and two-level triage. Here, 80 replicates per scenario are run in the Experimenter tool to evaluate two demands of 10 and 40 patients per day. In this context, two metrics are analysed to evaluate the operational performance: the total patient time in the system (TTS) and the waiting time to enter the medical consultation. Consequently, the results of the experiment determine that the medical consultation is the bottleneck. Therefore, it is validated that the number of doctors is the determining factor in operational performance management. Thus, increasing the number of doctors from one to two reduces TTS by 20% with low demand and by 28% with high demand, the impact of which is reflected in the waiting time to enter the medical consultation, which is reduced by 91% with low demand and by 56% with high demand. Finally, this study can serve as a guide for other healthcare centres to anticipate bottlenecks and validate changes virtually, thus ensuring improvements with a guaranteed impact.