Variations in volume of emergency surgeries and emergency department access at a third level hospital in Milan, Lombardy, during the COVID-19 outbreak

A retrospective, observational study was performed to assess all the emergency surgeries performed and the attendance number at the ED of a level III university hospital immediately before, during and after a progressive community lockdown in response to the COVID-19 pandemic. By using an anonymous hospital-based administrative database, automatically generated with data from ED software (PSNet, Hitech SpA, Software Engineering), the data on ED attendances were collected and analyzed along four time periods:

For each of these four periods, attendances at the ED were stratified according to specialties: general medicine, surgery, specialist examinations (ophthalmology, otolaryngology, traumatology, and urology), psychiatric examinations and attendances for domestic violence. Number of deaths in the ED and numbers of patients who left the ED without being seen by a physician (LWBS) were also collected. All of these data were compared with the same time periods in 2019.

Similarly, emergency surgical interventions during the same time periods in 2020 and in 2019 were compared.

Data are presented as means, standard errors (SE), and 95% studentized confidence intervals (CI). All the 95% studentized confidence intervals were computed with 2500 bootstrap iterations.

The Wilcoxon rank signed test at a 0.05 significance level was used to assess the differences in the per-day access distribution according to the following groups: medicine, surgery, specialist examinations, psychiatry, domestic violence, LWBS, and deaths.

For each category, drop percentages of the number of events in 2020 (x₂₀₂₀) with respect to the number of events in 2019 (x₂₀₁₉) were computed as follows: drop% = abs(x₂₀₁₉-x₂₀₂₀)/ x₂₀₂₀.

Matlab software (The MathWorks, Inc., Natick, MA, USA) was used to perform data analysis and to generate plots.

Admittances to the ED for medical complaints decreased, but less than surgical diseases, due to the high influx of severe COVID-19 patients. Correspondingly, a mean increase in mortality of 196% occurred, with a peak in the second period, when Italy had the peak of infections and of hospital and ICU admissions for COVID-19.

ED attendances reduction, although more contained, was also reported in the UK, with a 25% fall in visits during –not before- the first week following lockdown [7].

A frequently cited index of ED functioning, i.e. the percentage of patients who leave the ED without being seen by a physician, or during the diagnostic process [8, 9], showed a decrease for all four time periods examined. To our knowledge, there are no published data available regarding LWBS during mass casualty events such as pandemics. In our ED, the marked reduction compared to a previous “normal” year clearly demonstrates that people seeking care had severe conditions which were not amenable to treatment outside the hospital. For all the people who do not ultimately receive medical advice, probably for minor complaints, faster alternative tracks should be implemented during pandemics. Possibly, ad hoc facilities established outside of hospitals should be considered.

There are many aspects of the present study which need explanation. For example, in our ED the trend in visit reduction began when it seemed there were no infections in Milan, with 56 and 81% reductions in accesses for surgical and specialist examinations. In general, it is likely that people were concerned about contracting COVID-19 in hospital. In particular, ED are often crowded, and this situation was further emphasized by the media during all the pandemic. It is likely that many people experiencing mild symptoms may have decided that an ED would be a dangerous and unsafe place for non-COVID-19 patients. This is the case for admissions due to ophthalmologic, otolaryngological, urologic and orthopedic diseases. The reduction in attendances inversely corresponded with the increasing trend of SARS-CoV-2 infections.

The drop in minor traumatic injuries caused by traffic collisions is easily attributable to home confinement and the drastic reductions in vehicle traffic, due to the lockdown started on March 8. Vehicle circulation was only allowed for essential workers or for serious emergency reasons. Auto-certification was required and heavy fines were imposed in cases of false declarations. On March 17, the Lombardy Government declared an overall 60% decrease in social mobility in the region [10].

For accidents at work, generally trauma falls, the drop could be due to the closures of building sites and factories. Less or no contact between people due to closure of places of socialization, with reduced alcohol and drug use, can explain the reduced attendances for stab wounds due to street crimes like assault and robbery. Such decrease was also observed in the United States [11]. However, this phenomenon should have been balanced by domestic violence, caused by home confinement of abused women and children, as it was reported in France [12] and the U.S. [13], but this was not the case in our hospital. It is possible these cases will emerge when it is easier for people to move and seek help, as evidenced by the increase in ED attendances during Period 4.

What about emergency surgical cases -infections, ischemia and obstruction- which must be promptly addressed? The impact of the COVID-19 outbreak on emergency surgery in Policlinico Hospital has been significant: compared to the same time periods in 2019, surgical interventions had a 60% drop in 2020. This decrease can only partially be explained by the redistribution of cases in hospital hub designed by the Lombardy Emergency Task Force, and dedicated to time-dependent diseases -trauma, cerebrovascular accidents, coronary disease. Ideally, ED accesses for urgent and emergency conditions, such as abdominal infections, obstruction and ischemia should have remained nearly unchanged. Conversely, emergency surgery for infections, such as appendicitis, cholecystitis and diverticulitis, was performed for 14 patients, compared to 24 surgeries performed in 2019. This represents a 42% reduction. We did not observe a delay in presentation, as reported by a recent survey performed by a questionnaire sent to Italian hospitals practicing emergency surgery [14].

Reasons for reduced hospital access for infectious surgical disease remains to be explained. We can speculate that people were not directed to the ED and instead were treated conservatively, i.e. with antibiotics, by their general practitioners. If this is the case, and it can be confirmed from future statistics, the medical community should revaluate the role of out-of-hospital medical therapies in treating diseases traditionally considered of surgical interest. In-hospital non-operative management (NOM) has been suggested in recent literature for uncomplicated appendicitis, selected cholecystitis patients and colonic diverticulitis [15‐21]. In the COVID-19 era, this strategy was suggested by many international recommendations [22‐24] and has many advantages, first of all protecting patients and staff from possible intrahospital and in theatre virus transmission. Furthermore, NOM can save human resources and devices, and can allow ICU beds to be available. Moreover, recent literature reported an unexpectedly high rate of postoperative complications and mortality even after elective surgery [25, 26],for both infected but asymptomatic patients before surgery and patients who contracted COVID-19 after surgery [27].

Bowel and gastro-duodenal perforations halved in 2020, with 4 interventions in 2020 vs 8 interventions in 2019. Surgery for incarcerated umbilical, inguinal and incisional hernia dropped to only one case in 2020, compared to 10 cases in 2019. We suppose that home-confinement, accompanied by reductions in physical activity and hard work, may have contributed to the reduced surgeries for incarcerated hernia. However, in Spain, an increase in surgery for incarcerated hernia was reported [28], and we know that containment measures as self-isolation and home confinement were introduced in Spain as in Italy.

For gastro-intestinal perforations, we cannot identify a convincing and plausible explanation. Covered duodenal perforations, which can be treated conservatively with nasogastric suction and antibiotics, usually represent a minority of observed cases, and it seems inconsistent that such patients could stay at home and be cured only by fasting. The same for colon perforation, often caused by a complicated cancer. Obstruction, another frequent complication of colon cancer, was an uncommon finding during COVID-19 outbreak. In one case endoscopic placement of an endoprosthesis allowed surgery to be postponed for 2 weeks.

The number of surgeries for small bowel obstruction did not significantly differ between 2019 and 2020. Conservative treatment, with naso-gastric suction, nil per os and intravenous fluids, was the treatment of choice for no more than 72 h, as suggested by literature [29], and it is usually performed in the Emergency Surgery Department of Policlinico Hospital. Surgery was performed when an obstruction did not resolve or when contrast medium computed tomography showed a need for intervention without delay.

Severe COVID-19 has been associated with a marked inflammatory and prothrombotic state [30]. However no cases of mesenteric ischemia were diagnosed and operated on in COVID-19 patients during the outbreak.

Overall, the results of this study confirm a decrease in ED attendances for all medical and surgical complaints during the COVID-19 pandemic. The decrease in surgical patients was impressive and this led to a significant reduction in emergency surgeries. It is possible that some diseases were managed conservatively. However, if our data are confirmed in other settings, it is important to determine what consequences were incurred for the patients who did not seek medical attention, as well as the possible future rebound on the health care system.

We must acknowledge some limitations of the present work. The study did not analytically analyzed the single diagnoses of ED access to assess which diseases were missing with respect to the previous year.

Moreover, no updated data regarding surgeries performed at other hospitals in the metropolitan area of Milan are available; however, informal communications between general and emergency surgeons confirm that a drop in emergency surgeries was observed.

Finally, patients may have died at home due to complications of untreated surgical urgencies. However, it is currently difficult to assess possible changes in mortality rates for non-COVID-19 diseases from national and regional death registries.