The advent of the Covid-19 pandemic has forced global organizations of all types to adopt new rules necessary to block the spread of the virus. The organizational changes particularly affected the healthcare sector, for which it was necessary, given the strong reduction in resources, to reorganize the services offered with the aim of highly effective and efficient provision. This study aims to evaluate the impact of the rules adopted by the Cardarelli hospital (Naples) on the performance of the activities carried out. The study was carried out considering the length of stay (LOS) as an indicator of the department’s performance and the DMAIC continuous quality improvement cycle was used to evaluate the impact of the actions adopted. The analysis therefore involved the statistical comparison of the LOS in the years 2019 (without the pandemic) and 2020 (during the pandemic). The Mann–Whitney test was implemented through the Jamovi platform. Despite the reduction in the number of hospitalized patients, an average increase in LOS was observed for each class of patients in 2020, except for female patients with comorbidities, but in any case, these differences were not statistically significant. These increases reflect the new steps introduced to address the pandemic emergency but do not negatively impact the department’s performance.