In 2020, on March the 9th, the Italian Prime Minister announced the lockdown, which was officially closed on May the 4th. This extraordinary measure was necessary to contain the COVID-19 pandemic spread in Italy (1, 2). Healthcare systems were deeply reorganized, in order to both hold the burden of the pandemic and guarantee essential health services, with direct consequences on the organization of surgical activity (3, 4).

During this phase, patients' access to Emergency Department (ED) dramatically decreased, as already documented during the Taiwan SARS Epidemic in 2003 (5–8). This population's behavior, strongly motivated by the common perception of Hospitals as hotspots for infection, could have led to severe consequences. For example, the Italian Pediatric Hospital Research Network reported a small series of 12 cases of delayed access in severe conditions resulting from fear of COVID-19 infection (9), and similarly, a dramatic increase in the rate of out-of-hospital cardiac arrest was reported (10). Moreover, data from ISTAT (Statistical Italian Institute) revealed an increased overall mortality in the period between 20 February and 31 March 2020, if compared with the average of the previous years (11).

As well as cardiologic emergencies, emergency surgery outcomes could have been significantly affected by diagnostic delay due to the lockdown (12–14). In fact, a survey from the ACOI network showed a significant reduction in urgent interventions and an unusual delay in the presentation of non-traumatic abdominal emergencies (15). Moreover, a retrospective study about surgical emergencies documented a 32% reduction in the number of people presenting at the ED, compared with the previous year (16). A WSES survey documented the increased incidence of severe septic abdominal abscesses during the pandemic, especially for appendicitis and cholecystitis (16). However, clear data about the consequences of delayed access in ED to emergency surgery during the Pandemic are not available.

The aim of this study is to provide a detailed description of surgical emergencies and outcomes during the lockdown in a tertiary referral Italian hospital, compared with historical data from the same center.

During the 2020 lockdown, even if the overall number of ED accesses decreased, the number of patients surgically treated in emergency-urgency conditions did not decrease in an Italian tertiary referral center for emergency and trauma surgery. The overall analysis showed a statistically significant difference in abdominal pain prevalence as the main symptom and the complete absence of trauma patients in the 2020 group. This last result is easily understandable since this was a direct consequence of the travel limitation imposed by the Italian government. On the other hand, the data on pain as the main symptom finds a more complex explanation, which could be clarified by the sub-analysis results.

Peritonitis' sub-analysis showed that, in our series, 2020 patients waited significantly more before hospital access, as already hypothesized in other studies (7, 16) compared to 2019. A similar situation had already been described during SARS Epidemic in Taiwan in 2003 (6). Thus, this behavior is, very likely, a direct consequence of the fact that hospitals were perceived, especially during the early phase of the pandemic, as unsafe places, despite emergency cares never stopped on the national territory. Indeed, health facilities and, consequently, health workers were the most affected by the COVID-19 infection, as reported by Italian Istituto Superiore di Sanità (ISS) and by the Chinese experience (19).

The effects of delayed diagnosis in emergency conditions, especially in abdominal sepsis, are well known, as well as morbidity and mortality are time-dependent factors in those patients (20, 21). This diagnostic delay was, consequently, associated with a more severe clinical condition and a significantly worse prognosis. The most evident consequence was the dramatic increase in postoperative mortality in peritonitis patients in the 2020 group. Moreover, the lower incidence of ileostomy and the increased frequency of Hartmann's procedures performed in 2020 could be a direct consequence of more severe peritonitis found in this group of patients. On the other hand, secondary to a safer approach favored by surgeons to avoid unnecessary complications and re-interventions in a phase of great stress for the hospital, especially the intensive care units. Therefore, the cost of the pandemic was not only paid in terms of direct deaths from SARS-CoV2 infection, but also paid in terms of deaths due to delayed emergency condition treatments.

Nevertheless, the surgical approach did not change the use of minimally invasive techniques, despite the recommendations of some surgical societies (18), without consequences on the intra-hospital spread of COVID-19. Indeed, none of the staff of our Department, nor the patients, tested positive for the COVID-19 swab test during the lockdown. Actually, only one patient treated for emergency surgery, was resulted positive for the admission swab test, but it was completely asymptomatic. He was isolated in a COVID area before and immediately after surgery, and he has never passed through the General Surgery ward that was kept safe.

The retrospective design, the heterogeneity, the complexity of conditions and treatments, and the relatively small sample are the main limits of the study. However, this sample size allowed us to show the differences in terms of diagnostic delay and mortality. Moreover, even if the conclusions of the study are limited to the Italian Health System, a similar behavior was observed during the Taiwan SARS epidemic, in completely different conditions (5–8). We should consider that, in the early phase, all the involved Countries were equally unprepared and the national scientific societies produced similar guidelines. Furthermore, the modality of transmission and the consequences of the disease were not fully known and an effective vaccine had not yet been developed, which resulted in extremely cautious behavior of patients and institutions.

In conclusion, our results seem to confirm some previous observations about the severe consequences of diagnostic delay, in emergency surgery, during the early phase of the pandemic outbreak. Those findings could help health authorities to consider adequate countermeasures in order to guarantee hospital access to urgent-emergent non-pandemic conditions, in a difficult situation such as a pandemic outbreak.