Study design
We carried out an observational study according to a retrospective approach. The study protocol and the related informed consent form were approved by the local Ethical Review Board (protocol study number: 1382/20).
Our research primarily aimed at evaluating the impact of the extraordinary measures issued by the Italian MoH concerning the occurrence of infections at the surgical site in patients undergoing elective breast cancer surgery. To this purpose, two patients’ cohorts were retrospectively identified and compared according to the methods reported below.
Data collection
The data herein analyzed and presented relate to breast cancer patients with an indication to non-deferrable breast surgery according to the Guidelines for Surgical Care released by the American College of Surgeons (ACS)2 (Table 1). We also judged suitable for inclusion those breast cancer patients whose diagnosis had been made more than 1 month before. On this basis, the original table issued by the ACS has been enriched by this additional criterion, reported in the bottom row. Breast cancer patients who contributed data to our analysis were from 2 cohorts, namely, cohort 1, the lockdown cohort (LDC), and cohort 2, the non-lockdown cohort (NLDC). For patients from both these cohorts, a minimum 12-month follow up from breast surgery was required. Patients from the LDC underwent breast cancer surgery between the 15th March 2020 and the 4th May 2020. Within this latter time frame, an ad hoc multi-disciplinary team oversaw the selection of breast cancer patients undergoing surgery according to the previously cited criteria. To this aim, weekly meetings were held. One single representative member for each of the following professional figures was involved: a general surgeon, oncologist, radiotherapist and plastic surgeon. Adequate social distance and mask wearing were constantly respected10.
Patients from the LDC were compared with patients from the NLDC, i.e., patients having undergone non-deferrable breast cancer surgery and whose diagnosis had been made within the same time window postponed to the year 2019, i.e., between the15th March 2019 and 4th May 2019. Patients were deemed not eligible and excluded if one or more among the following characteristic/s was/were represented: aged 80 years or older, diagnosed with autoimmune disorders, in course of therapy with steroids and/or within the past 6 months, American Society of Anesthesiologists (ASA) score equal to/greater than (≥) 4, body mass index (BMI) equal to greater than 35, kidney/liver/bone marrow failure. Ad hoc, pre-piloted forms were used for data retrieving from medical records. Data extraction was performed by specifically trained personnel and focused on demographic features, relevant clinical and pathological characteristics, ASA score, type and exact duration of surgery, drains, pre-surgical therapy/ies and co-morbidities.
For all the patients who contributed data to the present analysis, breast surgery was performed by the same team. In addition, postsurgical controls were performed regularly and, as already mentioned, for a minimum of 12-months. The interval length between consecutive controls varied mainly on the basis of breast implants positioning. Indeed, in the presence of implants, controls were set biweekly over the first three months and every two weeks for two additional months. Conversely, if no implants had been placed, controls were scheduled twice per week for a minimum of 30 days. A culture specimen was collected when an infected wound was suspected by the surgeon or in case of pain or tissue tenderness, swelling, redness or heat, purulent drainage or body temperature > 38°C. SSIs were defined according to the criteria established by the Center for Disease Control and Prevention (CDC): purulent drainage (CDC#1), a positive aseptically collected culture, (CDC#2), at least one sign of inflammation with opening of the incision and absence of a negative culture (CDC#3), or physician diagnosis of infection (CDC#4)11.
The time elapsed between breast surgery and infection onset, prior therapy/ies (either medical or surgical), the need of re-hospitalization, and the impact on the postsurgical treatment administration were all recorded for each case of SSIs.
The present analysis does not include data from patients who were referred to other ambulatories following surgery or for whom the post-surgical controls were partially or totally unfeasible. The peri-operative measures routinely in place at our Surgical Division for the prevention of SSIs are fully consistent with the related recommendations from the World Health Organization (WHO) and have not changed over the last two years12 (Table 2). The measures adopted by the health care management team during the lockdown period in terms of limiting hospital accesses, sanitizing common areas such as ambulatories, waiting rooms and surgical rooms, interpersonal distancing, and use of individual protective devices are summarized in Table 3.
Statistical analysis
Results were reported as means, medians, standard deviations and ranges if related to quantitative variables, while qualitative variables will be reported as absolute frequencies. Associations were estimated throughout chi-square or fisher exact test. For quantitative variables, groups were compared by Mann-Whitney test. All the analyses were performed using the SPSS 21.0 software (SPSS Inc., Chicago, Illinois, USA).
Additional information
Ethical standards
Informed consent was obtained from all patients participating in the study. The research was conducted according to the principles established by the Declaration of Helsinki.