COVID-19: Pandemic surgery guidance

Abstract

Based on high quality surgery and scientific data, scientists and surgeons are committed to protecting patients as well as healthcare staff and hereby provide this Guidance to address the special issues circumstances related to the exponential spread of the Coronavirus disease 2019 (COVID-19) during this pandemic. As a basis, the authors used the British Intercollegiate General Surgery Guidance as well as recommendations from the USA, Asia, and Italy. The aim is to take responsibility and to provide guidance for surgery during the COVID-19 crisis in a simplified way addressing the practice of surgery, healthcare staff and patient safety and care. It is the responsibility of scientists and the surgical team to specify what is needed for the protection of patients and the affiliated healthcare team. During crises, such as the COVID-19 pandemic, the responsibility and duty to provide the necessary resources such as filters, Personal Protective Equipment (PPE) consisting of gloves, fluid resistant (Type IIR) surgical face masks (FRSM), filtering face pieces, class 3 (FFP3 masks), face shields and gowns (plastic ponchos), is typically left up to the hospital administration and government. Various scientists and clinicians from disparate specialties provided a Pandemic Surgery Guidance for surgical procedures by distinct surgical disciplines such as numerous cancer surgery disciplines, cardiothoracic surgery, ENT, eye, dermatology, emergency, endocrine surgery, general surgery, gynecology, neurosurgery, orthopedics, pediatric surgery, reconstructive and plastic surgery, surgical critical care, trans-plantation surgery, trauma surgery and urology, performing different surgeries, as well as laparoscopy, thora-coscopy and endoscopy. Any suggestions and corrections from colleagues will be very welcome as we are all involved and locked in a rapidly evolving process on increasing COVID-19 knowledge.

Full text

COVID-19: Pandemic surgery guidance
Björn L.D.M. Brücher
1,2,3,*
, Giuseppe Nigri
4
, Andrea Tinelli
5
, Jose Florencio F. Lapeña Jr.
6
, Eloy Espin-Basany
7
,
Paolo Macri
8
, Edouard Matevossian
9
, Sergio Ralon
10
, Ray Perkins
11
, Rainer Lück
12
, Rainer Kube
3
, Jose MC da Costa
13
,
Yoav Mintz
14
, Mesut Tez
15
, Sixtus Allert
16
, Selman Sökmen
17
, Arkadiusz Spychala
18
, Bruno Zilberstein
19
,
Frank Marusch
20
, Mohammad Kermansaravi
21
, Witold Kycler
18
, Diego Vicente
22
, Michael A. Scherer
23
,
Avraham Rivkind
14
, Nelson Elias
24
, Grzegorz Wallner
25
, Franco Roviello
26
, Lúcio Lara Santos
27
,
Raimund J.C. Araujo Jr.
28
, Amir Szold
29
, Raúl Oleas
30
, Marjan Slak Rupnik
1,2,31
, Jochen Salber
32
,
Ijaz S. Jamall
1,2,33
, Alexander Engel
34
, for the Pandemic Surgery Guidance Consortium (PSGC)
1
Theodor-Billroth-Akademie
Ò
, Germany, USA
2
INCORE, International Consortium of Research Excellence of the Theodor-Billroth-Academy
Ò
, Germany, USA
3
Department of Surgery, Carl-Thiem-Klinikum, Cottbus, Germany
4
Department of Medical and Surgical Sciences and Translational Medicine, Sapienza University of Rome, St. Andrea University
Hospital, Rome, Italy
5
Department of Obstetrics and Gynecology, Veris delli Ponti Hospital, Scorrano, Lecce, Italy
6
Department of Otorhinolaryngology, College of Medicine-Philippine General Hospital, University of the Philippines Manila, Manila,
Philippines
7
Department of Surgery, Vall d’Hebron, Universitat Autonoma de Barcelona, Barcelona, Spain
8
Department of Thoracic Surgery, Istituto Clinico Humanitas CCO, Catania, Italy
9
Department of Surgery, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
10
Department of Surgery, Hospital General San Juan de Dios, Universidad de San Carlos de Guatemala, Calle, Guatemala
11
New Liberty Proteomics Corporation, New Liberty, KY, USA
12
Department of Surgery, Sana Klinikum Hameln-Pyrmont, Hameln, Germany
13
Centro de Imunologia e Biologia Parasitária, Scientific Director of Center for Study in Animal Science, ICETA, University of Porto,
Porto, Portugal
14
Department of General Surgery and Shock Trauma Unit, Hadassah-Hebrew University Medical Center, Ein Kerem,
Jerusalem, Israel
15
Department of Surgery, Ankara Numune Hospital, Ankara, Turkey
16
Department of Plastic, Aesthetic and Hand Surgery, Sana Klinikum Hameln-Pyrmont, Hameln, Germany
17
Colorectal and Pelvic Surgery, Dokuz Eylül University Hospital, Medipol University, Izmir, Istanbul, Turkey
18
Gastrointestinal Surgical Oncology Department, Greater Poland Cancer Centre, Poznan, Poland
19
Cancer Institute, Hospital das Clínicas, School of Medicine, University of São Paulo, São Paulo, Brazil
20
Department of Surgery, Ernst von Bergmann Hospital, Potsdam, Germany
21
Minimally Invasive Surgery Research Center, Iran University of Medical Sciences, Tehran, Iran
22
Department of Surgery, Uniformed Services University of the Health Sciences & the Walter Reed National Military Medical Center,
Bethesda, MD, USA
23
Department for Orthopedics and Trauma Surgery, Helios Amper Hospital Dachau, Dachau, Germany
24
Orthopedic Department, Vila Velha Hospital, Vila Velha, Espirito Santo, Brazil
25
Department of Surgery, Medical University of Lublin, Lublin, Poland
26
Surgical Oncology, University of Siena, Siena, Italy
27
Surgical Oncology Department –Portuguese Institute of Oncology, Porto, Portugal
28
Department of Surgery, Federal University of Piauí, Teresina, Piauí, Brazil
29
Assia Medical Group, Assuta Medical Center, Tel Aviv, Israel
30
Surgical Oncology, HPB and Liver Transplantation, Ecuadorian Cancer Institute, Quito, Ecuador
31
Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
32
Department of Surgery, UK Knappschaftskrankenhaus, Ruhr University, Bochum, Germany
33
Risk-Based Decisions Inc., Sacramento, CA, USA
34
Department of Colorectal Surgery, Royal North Shore Hospital, University of Sydney, Australia
*Corresponding author: b-bruecher@gmx.de
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0),
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
4open 2020, 3,1
Available online at:
ÓB.L.D.M. Brücher et al., Published by EDP Sciences, 2020
www.4open-sciences.org
https://doi.org/10.1051/fopen/2020002
BRIEF REPORTBRIEF REPORT

Abstract
–
Based on high quality surgery and scientific data, scientists and surgeons are committed to pro-
tecting patients as well as healthcare staff and hereby provide this Guidance to address the special issues cir-
cumstances related to the exponential spread of the Coronavirus disease 2019 (COVID-19) during this
pandemic. As a basis, the authors used the British Intercollegiate General Surgery Guidance as well as recom-
mendations from the USA, Asia, and Italy. The aim is to take responsibility and to provide guidance for surgery
during the COVID-19 crisis in a simplified way addressing the practice of surgery, healthcare staff and patient
safety and care. It is the responsibility of scientists and the surgical team to specify what is needed for the pro-
tection of patients and the affiliated healthcare team. During crises, such as the COVID-19 pandemic, the
responsibility and duty to provide the necessary resources such as filters, Personal Protective Equipment
(PPE) consisting of gloves, fluid resistant (Type IIR) surgical face masks (FRSM), filtering face pieces, class
3 (FFP3 masks), face shields and gowns (plastic ponchos), is typically left up to the hospital administration
and government. Various scientists and clinicians from disparate specialties provided a Pandemic Surgery
Guidance for surgical procedures by distinct surgical disciplines such as numerous cancer surgery disciplines,
cardiothoracic surgery, ENT, eye, dermatology, emergency, endocrine surgery, general surgery, gynecology,
neurosurgery, orthopedics, pediatric surgery, reconstructive and plastic surgery, surgical critical care, trans-
plantation surgery, trauma surgery and urology, performing different surgeries, as well as laparoscopy, thora-
coscopy and endoscopy. Any suggestions and corrections from colleagues will be very welcome as we are all
involved and locked in a rapidly evolving process on increasing COVID-19 knowledge.
Keywords: Anesthesia, Cancer, Cardiothoracic surgery, China, Coronavirus, COVID-19, Dermatology,
Elective surgery, Emergency, Endocrine surgery, Endoscopy, ENT, Epidemic, Epidemiology, Europe, Face
masks, General surgery, Germany, Guidance, Gynecology, Inflammation, Italy, Laparoscopy, Laparotomy,
Morbidity, Mortality, N95 masks, Neurosurgery, Orthopedics, Pandemic, Patient safety, Pediatric surgery,
Pneumonia, Protection, Reconstructive and plastic surgery, Surgical critical care, Respiratory masks, SARS-
CoV-2, Sepsis, Surgery, Thoracoscopy, Transplantation surgery, Trauma surgery, Urology, Virus
Introduction
On January 30, 2020 the World Health Organization
(WHO) stated on its Situation Report –10 that “the Emer-
gency Committee on the novel coronavirus (2019-nCoV)
under the International Health Regulations (IHR 2005) is
meeting today to discuss whether the outbreak constitutes
a public health emergency of international concern”[1]
and stated on March 11, 2020 in its Situation Report –
51, that “....the assessment that the Coronavirus disease
2019 (COVID-19) can be characterized as a pandemic”[2].
COVID-19 is caused by a single-stranded ribonucleic
acid (ssRNA) virus associated with severe acute respiratory
syndrome corona virus 2 (SARS-CoV-2) which was first
detected in Wuhan, Hubei province in China in December
2019 [3]. COVID-19 is a clade within the subgenus Sarbe-
covirus, Orthocoronavirinae subfamily, but differs from
two other strains, the Middle East respiratory syndrome
coronavirus (MERS-CoV) and the severe acute respiratory
syndrome coronavirus (SARS-CoV), and is suggested to
have originated in bats and/or pangolins [4,5].
Before the outbreak, SARS-CoV-2 circulated among
individuals for several weeks and one way it likely entered
Europe was through an unrecognized infection by a traveler
from Singapore to France on January 24, 2020 where some
21 people were exposed at a ski resort [6]. Coronavirus trans-
mission occurs by physical contact, and through the inhala-
tion or mucous membrane absorption of airborne droplets
from infected individuals [7,8] and contrary to assumptions,
SARS-CoV-2 has shown no weakening in warm and humid
conditions to date [9]. After entering the host, the SARS-
CoV-2 genome is transcribed and translated with common
cold-like symptoms after an incubation time of 2–14 days
with a mean incubation period of 5.2 days (95% confidence
interval [CI]: 4.1–7.0) [3]. The wide spectrum of reported
symptoms includes fever, cough, myalgia and fatigue with
the most common serious manifestation being pneumonia.
Less common symptoms are headache, sputum produc-
tion, diarrhea, malaise, shortness of breath/dyspnea and
respiratory distress and even anosmia, hyposmia, and dys-
geusia [10] explain why its impact in COVID-19 patients
from the ENT perspective was raised [11]. Importantly
anosmia (loss of smell) as a symptom of COVID-19 infec-
tion in the absence of other symptoms was reported which
is of significance, as “those patients do not meet current cri-
teria for testing or self-isolation”[12].
In terms of severity, some 81% are mild (e.g., no or mild
pneumonia), 14% have been reported as being severe
(dyspnea, respiratory frequency 30/min, blood oxygen
saturation 93%, partial pressure of arterial oxygen to frac-
tion of inspired oxygen ratio <300, and/or lung infiltrates
>50% within 24–48 h) and 5% have been noted to be crit-
ical (respiratory failure, septic shock, and/or multiple organ
dysfunction or failure) with an overall case-fatality rate
(CFR) of 2.3% [13]. It is important to note that patients
between the ages of 70–79 years have an 8.0% CFR and
cases 80 years and older have a 14.8% CFR with 49% of
critical cases reporting a fatal outcome. Taken together,
some 80% of infections will be mild, and 20% will be mod-
erate or seriously ill.
B.L.D.M. Brücher et al.: 4open 2020, 3,12

These data have made clear that such an outbreak with
an exponential increase of infected patients can rapidly
overwhelm any healthcare system. To understand why hos-
pital capacities need to be increased rapidly, an assumption
of a triple 10% scenario (a likely underestimation of the
reality but provided here as an illustration) calculation for
Germany with 83,783,942 citizens, which has 450,000 hospi-
tal beds and 28,000 intensive care unit (ICU) beds shows
that hospital capacities will urgently need to be increased
(Fig. 1,Data retrieved from [14]).
A detailed, complete comprehensive and robust infec-
tion workflow for a COVID-19 case had been proposed
most recently [15,16]. Otherwise practical guidance was
missing, until our British colleagues provided on March
26, 2020 the Intercollegiate General Surgery Guidance on
COVID-19 and updated it on March 27, 2020 (Fig. 2)[17].
The following recommendations serve as Pandemic Sur-
gery Guidance during the current exponential spread of the
COVID-19 throughout the world (Fig. 3).
The objective is to take responsibility to provide guid-
ance for surgery in the COVID-19 crisis in a more practical
way addressing practice, healthcare staff and patient safety.
As scientists and surgical teams decide what is needed for
the protection of patients and staff during such a pandemic,
the hospital administration together with the government
have the obligation to provide the necessary supplies such
as filters, Personal Protective Equipment (PPE) consisting
of gloves, fluid resistant (Type IIR) surgical face masks
(FRSM), filtering face pieces (FFPs), class 3 (FFP3 masks),
face shields, and gowns (plastic ponchos). The suggested
Guidance is a simplified way to address decision-making
for our colleagues and staff performing surgery, for the
healthcare team and to ensure patient safety and care
(Fig. 3).
Suggestions and corrections from colleagues will be wel-
come as we are all involved in a dynamically developing
process on increasing our collective COVID-19 knowledge.
Therefore, the proposed recommended steps are listed fol-
lowed by the rationale for each component of the Guidance.
Considerations
(1) Emergency Surgery
!COVID-19-testing and risk assessment.
!Pneumonia assessment by plain chest X-ray versus 3
quadrant ultrasound versus thoracic CT.
!Every surgery entails higher patient and staff risk.
1 Rationale
1.1 COVID-19-testing and risk assessment
Each patient should undergo COVID-19-testing including a
health risk assessment. The European Centre for Disease
Prevention and Control (ECDC) defined discharge criteria
[18]. In Accordance to the Ministero della salute, Consiglio
Superiore di Sanità, Italy (February 28, 2020), “a COVID-
19 patient can be considered cured after the resolution of
Figure 1. Calculated assumption of a triple 10% scenario for Germany with 83,783,942 citizens, which has 450,000 hospital beds and
28,000 intensive care unit (ICU) beds although it is a likely underestimation of reality. This figure reveals the necessity of increasing
hospital capacities urgently needed during COVID-19 pandemic. Citizen numbers in accordance to Worldometers Website [14].
(Access at March 19, 2020).
B.L.D.M. Brücher et al.: 4open 2020, 3,1 3

Figure 3. Pandemic Surgery* Guidance. *Surgery includes surgical procedures by distinct surgical disciplines such as numerous
cancer surgery disciplines, cardiothoracic surgery, ENT, eye, dermatology, emergency, endocrine surgery, general surgery, gynecology,
neurosurgery, orthopedics, pediatric surgery, reconstructive and plastic surgery, surgical critical care, transplantation surgery, trauma
surgery and urology, performing different surgeries, as well as laparoscopy, thoracoscopy and endoscopy.
Figure 2. Intercollegiate general surgery guidance on COVID-19 [17].
B.L.D.M. Brücher et al.: 4open 2020, 3,14

symptomsand2negativetestsforSARS-CoV-2at24-hour
intervals”. In China, patients considered to be discharged,
need to meet the following criteria: afebrile for >3 days,
Improved respiratory symptoms, pulmonary imaging shows
obvious absorption of inflammation, and nucleic acid tests
negative for respiratory tract pathogen twice consecutively
(sampling interval 24 h). Currently, the recommendation
is improved clinical signs plus two 2 negative tests for
SARS-CoV-2.
Nucleic acid amplification tests (NAAT), such as real-
time polymerase chain reaction (RT-PCR) are mandatory.
Information about specimen collection and procedures are
available from the WHO [19]. At present, RT-PCR is the
gold-standard performed on nasopharyngeal and/or throat
specimens in accordance to the Centers of Disease Control
(CDC) with a high specificity (low/no rate of false positive
findings) but with a low sensitivity ([20,21]reviewed in
[22]). There is a dynamic process of development of new
serological assays and their approval by the regulatory
agencies.
A recent study showed that negative SARS-CoV-2
nasopharyngeal testing does not mean that the individual
is not infected as 8 out of 10 children with negative
nasopharyngeal testing revealed persistently positive rectal
swabs testing suggesting the possibility of fecal–oral trans-
mission [23]. This is concordant with the most recent
findings that COVID-19 was measured in sewage
3 weeks before the first case was reported in the Nether-
lands [24].
Despite the need for clinicians to be aware of false nega-
tive tests, and although RT-PCR is the gold-standard, rapid
tests may be considered such as IgG/IgM antibody lateral
flow assay or nCoV-19 Antigen in NP swabs. In Wuhan,
China, “throat-swab specimens were obtained for SARS-
CoV-2 PCR re-examination every other day after clinical
remission of symptoms, including fever, cough, and dyspnea,
but only qualitative data were available”[25].
The WHO released early guidance for laboratory screen-
ing [19,26]. Because it takes 5–10 days to make IgM anti-
bodies (and IgG antibodies develop later), there will be a
highfalsenegativerateforIgG/IgMtestsamongthose
tested early without symptoms. Around day 10 after symp-
tom onset, IgG and IgM antibodies increased with serocon-
versionwithin3weeks[27].
The ECDC released on March 25, 2020 the 7th update
of a rapid risk assessment [28]. However, this document
describes the dynamics of the COVID-19 pandemic in Eur-
ope as rapid information but does not provide a risk assess-
ment for practical use. Health care employees need a risk
assessment for patient triage. To meet these needs, various
hospitals individually have developed a risk assessment to
try to stratify the decision-making process of where each
patient should be triaged.
Recently the date providing endpoints, such as of
admission to intensive care units, or invasive ventilation,
or death from 1590 laboratory-confirmed hospitalized
patients in 575 hospitals in 31 province/autonomous
regions/provincial municipalities across mainland China
between December 11, 2019 and January 31, 2020 were
analyzed [29]. After adjusting for age and smoking status,
the following comorbidities with their hazard ratio (HR)
and 95% CIs were determined:
COPD (HR: 2.681, 95% CI: 1.424–5.048);
Diabetes mellitus (HR: 1.59, 95% CI: 1.03–2.45);
Hypertension (HR: 1.58, 95% CI: 1.07–2.32); and
Malignancy (HR: 3.50, 95% CI: 1.60–7.64).
Patients were further stratified in accordance with com-
posite endpoints in terms of numbers of comorbidities as a
greater number of comorbidities correlated with poorer clin-
ical outcomes:
1 comorbidity (HR: 1.79, 95% CI: 1.16–2.77);
2 comorbidities (HR: 2.59, 95% CI: 1.61–4.17).
Clinically it is urgently necessary to stratify COVID-19
patients before admission and/or any surgical procedures
during the COVID-19 pandemic.
Laboratory tests in COVID-19 patients often show a
decrease of platelets and lymphocytes with increases of lac-
tate dehydrogenase (LDH), troponin, C-reactive protein
(CRP), D-dimer, serum ferritin, and interleukin 6 (IL-6)
[25]. A recommendation using a specimen collection kit with
instructions has been developed and is in accordance to the
provided CDC criteria [30].
1.2 Pneumonia assessment e.g. by plain chest
X-ray/3 quadrant ultrasound/thoracic CT
Early COVID-19 infection and effects on the lungs are cru-
cial in this pandemic, as the disease dynamics in many
reported patients can occur within a couple of days result-
ing in increased mortality. Pneumonia assessment can be
done alongside clinical investigation and auscultation e.g.,
by plain chest X-ray, 3 quadrant ultrasound, and thoracic
computed tomography (CT). Although controversial, chest
CT should be considered and where indicated, an abdomi-
nal CT or an additional chest CT scan should be taken into
consideration as well.
Chest CT might contribute as an early diagnostic and
monitoring tool for COVID-19 pneumonia. Patients with
chest CT scans and signs of pneumonia could be quaran-
tined while waiting for RT-PCR test results but it needs
to be taken into account that chest CT in COVID-19
patients reveals a high specificity between 93 and 100%
but a moderate sensitivity of between 72 and 94% [31].
Additionally, chest CTs might help to stratify patients
especially in the absence of rapid access of COVID-19 test-
ing, although a negative chest CT might not exclude
COVID-19 infections [32].
Some have argued that the chest CT should not be part
of COVID-19 diagnostic criteria [33–37], while others favor
CT scans [38–43]. One major argument for performing a
CT chest scan is the fact that pneumonia was radiologically
diagnosed in some 67% of COVID-19 negative cases and in
94% of COVID-19 positive patients [44]. In Hubei, China,
CT findings were included as evidence of clinical diagnosis
of COVID-19 patients [45] while this recommendation was
B.L.D.M. Brücher et al.: 4open 2020, 3,1 5

removed in the sixth published version [46]. Even the rates of
RT-PCR confirmed COVID-19 infections and synchronous
normal CT-findings vary greatly between 2% [47,48]and
56% [49].
1.3 Every surgery entails higher patient and staff risk
In general, every kind of surgery (including endoscopies and
minimally invasive surgery, such as laparoscopy, thora-
coscopy) is seen as entailing higher risks.
(2) Planned Surgery
!COVID-19-testing and risk assessment.
!Walking/climbing stair-test & blood gas.
!Postpone if possible (every surgery entails higher
patient risk).
!Determine planned list and execute cancelation.
2 Rationale
2.1 COVID-19-testing and risk assessment (see 1.1)
2.2 Walking/climbing stair-test and blood gas
Easy, inexpensive, and almost forgotten approaches con-
sist of walking/climbing stair-test and blood gas analysis.
For example, the 2 stairs climbing capacity with post-test
pO
2
> 91% has peri-operative prognostic importance [50].
2.3 Postpone if possible (every surgery entails higher
patient risk)
The President of the Robert-Koch-Institute (RKI) sug-
gested postponing all elective surgical procedures and inter-
ventions in an interview on February 28, 2020 [51].
Furthermore, surgery in general is seen at higher risk for
transmission of respiratory infections and especially poten-
tially inducing fatal patient outcome in cases where a
COVID-19 diagnosis is overlooked and/or diagnosed later
[52]. Therefore, surgery is a high-risk venture for COVID-19
patients.
In Germany, hospitals acted early to increased risk
posed by COVID-19 risk, followed by the German Govern-
ment. On Thursday March 12, 2020 the German Govern-
ment decided that all justifiable elective admissions,
surgical procedures and interventions should be postponed
to increase expected capacities in terms of patient beds,
intensive care unit (ICU) beds and ventilators [53]. Hospi-
tals were advised to postpone elective surgeries as
COVID-19 capacities were judged to be increased nation-
wide immediately and surgical care should be limited to
life-threatening diseases to minimize unnecessary resources
in manpower, patient beds and ICU beds, ventilators,
antiseptic foaming and use of PPE.
Tufts Medical Center in Massachusetts canceled all
planned (elective) surgery early in 2020 calendar week 2,
which was followed by the US Surgeon General Jerome
Adams’advice on March 14, 2020 via Twitter [54]. The
Centers for Medicare and Medicaid Services (CMS) released
on March 18, 2020 a tiered framework as potential help for
hospitals and health systems to evaluate suspected
COVID-19 needs [55]. On March 19, 2020, the CMS
together with the CDC recommended postponing elective
surgery in a press release [56]. The United Kingdom reacted
on March 17, 2020 [57].
Citing evolving evidence from China, Italy and Iran that
otolaryngologists were among the highest risk group of
contracting the virus while performing upper airway proce-
dures and examinations, the American Academy of
Otolaryngology Head and Neck Surgery AAO-HNS) issued
a policy statement limiting care to time-sensitive and emer-
gent problems and the routine use of appropriate PPE
whentreatingpatientsinallagegroups[58].
2.4 Determine planned list and execute cancelation
Complex surgery which itself is associated with higher mor-
bidity and mortality should be deferred [59]. The ACS has
provided guidelines for triage to potentially determine
planned lists of those procedures which can be canceled
[60]. This decision is a clinical one depending on the patient,
hospital infrastructure and actual local COVID-19 burden.
(3) Strategy
!Prefer Non-surgical approach
!conservative if justifiable
!Consider Risk Reduction (for patients and staff)
!Surgery in selected cases only
!Risk Laparotomy = Laparoscopy if use of
!Filtered Gas Smoke Exhaust or
!Water Lock Filters
!Consider Gasless Laparoscopy
!Stoma > Anastomosis
3 Rationale
3.1 Prefer Non-surgical approach
(conservative if justifiable)
COVID-19 pneumonia carries a high mortality rate espe-
cially during peri- and post-operative times, which is why
any kind of surgical treatment should be scrutinized very
carefully and postponed if possible. Therefore, preoperative
check-up is of importance in terms of patient history (con-
tact within the last 14 days with suspected/confirmed
infected cases).
The Australian and New Zealand Hepatic, Pancreatic
and Biliary Association (ANZHPBA) provided three surgi-
cal COVID-19 response phases into (Phase I)Semi-Urgent
Setting (Preparation Phase) (few COVID-19 patients, hos-
pital resources not exhausted, institution still has ICU ven-
tilator capacity and COVID-19 trajectory not in rapid
escalation phase), (Phase II)Urgent Setting (many
COVID-19 patients, ICU and ventilator capacity limited,
operating room supplies limited) and (Phase III)
B.L.D.M. Brücher et al.: 4open 2020, 3,16

“Wartime”footing (Hospital resources are all routed to
COVID-19 patients, no ventilator or ICU capacity, operat-
ing room supplies exhausted; only patients in whom death
is likely within hours if surgery is deferred) [61]. Within this,
a complex triage scenario is provided including categoriza-
tion of hepato-biliary surgical procedures.
Otherwise, emergency patients may be subdivided surgi-
cally in an easy way into: (1) urgent surgery required (no
time delay allowed), (2) emergency operation required
and (3) observation.
Various scoring systems and/or calculators are available
for stratification of pre-hospital health status and comor-
bidities, physiology and outcome risk which often had not
been explicitly validated [62]:
!American Society of Anesthesiologists Physical Status
Grading (ASA-PS) [63];
!Charlson Comorbidity Index (CCI) [64];
!Physiological and Operative Severity Score for the
Enumeration of Mortality and Morbidity (POSSUM)
[65];
!Surgical Risk Scale (SRS) [66];
!Surgical Mortality Score (SMS) [67];
!Surgical Risk Score [68];
!Physiological Emergency Surgery Acuity Score
(PESAS) [69];
!Surgical Apgar Score (SAS) [70];
!Perioperative Mortality Risk Score (PMRS) [71];
!American College of Surgeons National Surgical Qual-
ity Improvement Programme (ACS-NSQIP) universal
surgical risk calculator [72];
!Surgical Outcome Risk Tool (SORT) [73];, and
!Emergency Surgery Acuity Score (ESAS) [74].
Although there is no Level 1 evidence, surgery in poten-
tial COVID-19 patients is seen as a high-risk venture which
is why recommendations from various international soci-
eties favor a non-surgical approach, if justifiable. Non-
operative conservative treatment for example includes
cholecystotomy and drainage for acute cholecystitis, inser-
tion of percutaneous transhepatic cholangiography drai-
nage (PTCD) in cholangitis, interventional embolization
of acute gastrointestinal bleeding, antibiotic treatment for
appendicitis, or even hernia reduction under sedation for
incarcerated hernia.
3.2. Consider Risk Reduction (for patients and staff)
3.2.1 Surgery in selected cases only
The general recommendation is to select surgical cases to
minimize the surgical trauma as much as possible indepen-
dent of the size of incision for ports in laparoscopy or
laparotomy.
3.2.2 Risk Laparotomy = Laparoscopy (includes endoscopy
and thoracoscopy) “if use of”
3.2.2.1 Filtered Gas Smoke Exhaust or
3.2.2.2 Water Lock Filters
We review at first the development of how recommenda-
tions were created and point out, which knowledge needs
to be taken into account, which explains why the stated risk
of laparotomy compared to laparoscopy needs to be seen in
a much more differentiated way if available knowledge is
addressed and some conditions are considered.
At first, surgeons in Wuhan, China recommended
highly selecting laparoscopy [75]; subsequently laparo-
tomy was judged to be more favorable than laparoscopy
due to the following arguments put forward by various
societies:
The surgical smoke during laparoscopy using electri-
cal or ultrasonic equipment for 10 minutes results in
a significantly higher particle concentration within
the smoke compared to laparotomy ([76]reviewed in
[77]) although it is possibly the result of the smoke
concentrating in a closed space in contrast to smoke
that is emitted continuously during laparotomy.
The standard “surgical masks alone do not provide
adequate protection from surgical smoke”[78].
More than 600 compounds and gases or more can be
identified in surgical smoke [79,80].
This includes viruses such as human immunodefi-
ciency virus (HIV), human papillomavirus (HPV),
bovine papillomavirus (BPV) and hepatitis B virus
(HBV) [76,81–89].
“Human papillomavirus (HPV) types ... seem to have
a predilection for infecting the upper airway mucosa,
and laser plume containing these viruses may repre-
sent more of a hazard to the surgeon”[83]. Recurrent
respiratory papillomatosis (RRP) is caused by HPV-
type 6 (HPV-6) and HPV-type 11 (HPV-11) and asso-
ciated with exophytic lesions of the airway that are
friable and bleed easily [90].
“Swabs from 110 patients in nine separate treatment
sessions as well as from five pre-filter canisters, four
fume vacuum tubes, and from the nasopharynx, eye-
lids, and ears of the laser surgeon before and after
laser surgery”revealed in up to 60% papillomavirus
DNA to be identified in swabs and even in one of five
pre-filter canisters where HPV DNA was positive [81].
In a recent study, the “concentration number of 0.3
lm and 0.5 lm particles reached the maximum after
10 min of electrosurgical treatment; however, the con-
centration number of 5 lm particles began to decrease
after 5-15 min of the treatment”plus “the cumulative
particle numbers of 0.3 lm and 0.5 lm in laparoscopic
operation were higher than those of laparotomy after
10 min of the treatment”suggesting that “surgical
smoke prevention should use smoke evacuator”and
that “health-care workers should also wear a highly
efficient tight seal-fit mask in the OR”to avoid risk
and damage [76].
The Royal College of Surgeons of England (RCS), Royal
College of Physicians and Surgeons of Glasgow, the Royal
College of Surgeons of Edinburgh and the Royal College
of Surgeons of Ireland released guidance for surgeons on
March 20, 2020 [91]. The American College of Surgeons
(ACS) released elective case triage guidelines for surgical
care on March 24, 2020 [60]. Afterwards an intercolle-
giate general surgery guidance arrived on March 26, 2020
which was updated on March 27, 2020 (Fig. 2)[17].
B.L.D.M. Brücher et al.: 4open 2020, 3,1 7

The recommendations of British and US societies had
been reviewed [17,55–57,60,91]. Therefore, it had been
assumed that laparotomy was favored over laparoscopy,
and laparoscopy, thoracoscopy, and endoscopy should be
performed on selected cases only and that although
COVID-19 data in terms of surgical smoke are still missing,
protection of viral transmission by surgical smoke would
need to be addressed through the use of PPE based on
earlier evidence.
Following publication of these guidelines, surgical soci-
eties around the world expressed disagreement with the
recommendation to strictly avoid laparoscopy. Although
laparoscopic surgery is considered an aerosol generating
procedure (AGP), this aerosol together with the CO
2
pneu-
moperitoneum is in a controlled cavity.
In open surgery electrosurgical instruments produce
smoke and aerosolization of tissue as much as in laparo-
scopy; however the dissipation of this material is to the
open operating theatre space affecting all staff. Smoke evac-
uation attached to monopolar devices are helpful but have
limited efficacy. Moreover, glove tearing and fluid or blood
splashing can cause direct contact with bodily fluids
whereas in laparoscopy these are avoided.
The Society of American Gastrointestinal and Endo-
scopic Surgeons (SAGES) together with the European
Association for Endoscopic Surgery (EAES) stated that
“either open, laparoscopic or robotic”surgeries need to be
taken into account and that “protective measures are
strictly employed for OR staff safety and to maintain a func-
tioning workforce”[92].
However, it was pointed out by the SAGES that the evi-
dence in terms of favoring laparotomy over laparoscopy is
low ([77]reviewed in [92]).
Another parameter that needs to be considered is the
quicker discharge of patients following laparoscopic surgery.
In this COVID-19 pandemic, hospital resources are scarce
and hospital beds, healthcare personnel and equipment
should be saved for critically ill patients rather than stan-
dard post-operative care of surgical patients. Laparoscopy
allows for faster discharge from hospitals and less dealing
with surgical wounds and surgical site infections (SSIs). This
is why the two largest world associations dealing with
laparoscopy, the Society of American Gastrointestinal and
Endoscopic Surgeons (SAGES) and the European Associa-
tion for Endoscopic Surgery (EAES), quickly released their
recommendations regarding surgical response to COVID-
19 (Fig. 4)[93].
Experience in laparoscopic surgery was published to dis-
seminate knowledge and provide guidelines for minimally
invasive surgery procedures. The China and Italy experi-
ences are particularly helpful by providing suggestions like
using low pressure peritoneum, use of balloon trocars, evac-
uating all pneumoperitoneum before trocar removal or spec-
imen extractions [77].
Figure 4. Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) and the European Association for Endoscopic
Surgery (EAES) recommendations regarding surgical response to COVID-19 crisis [93].
B.L.D.M. Brücher et al.: 4open 2020, 3,18

Remark
Knowledge which needs to addressed
Screening 3363 individuals enrolling 246 individuals with
exhaled breath samples explored the value of respiratory
droplets and aerosol routes of transmission with a particular
focus on coronaviruses, influenza viruses, and rhinoviruses
and showed that surgical face masks significantly reduced
detection of influenza virus RNA in respiratory droplets
and coronavirus RNA in aerosols, with a trend toward
reduced detection of coronavirus RNA in respiratory dro-
plets [94].
The importance of the appropriate smoke extraction
equipment had been pointed out earlier [95]. Although cell
particles had been found in the smoke plume, until now the
risk to the OR staff is still not defined [96] and the hazards
in terms of tumor cells in the surgical smoke from tumor dis-
section by ultrasonic scalpel are unclear at present [88].
Mintz et al. together with the Technology Committee of
the EAES pointed out that “Standard electrostatic filters
used for ventilation machines have the capability of filtering
known bacterial and viral loads with great efficiency and
most are certified for 99.99% effective protection against
HBV and HCV which have a diameter of 42nm and 30-60
nm respectively”and that “SARS-CoV-2 has a larger diam-
eter of 70-90 nm”which is why “the same filtering efficiency
can be expected to apply for new virus”([97–99]reviewed in
[100]).
Due to this, the capability of evacuating smoke was
effectively shown by surgeons in Israel and Italy in five
operations without using an active suction system, which
was accepted for publication in Annals of Surgery on April
03, 2020 [100]:
!Cholecystectomy,
!Inguinal hernia repair,
!Total Mesorectal Excision (TME),
!Transanal Total Mesorectal Excision, and
!Anterior resection of the rectum.
Each surgeon reported very good efficiency of the pas-
sive smoke evacuation system during laparoscopic proce-
dures and that “the filter system should be discarded
according to hospitals protocols for infection control ”.
The EAES technology committee provided guidance for
safe use of laparoscopy, to evacuate gas and smoke from the
abdomen through a simple low cost adequate filter, to evac-
uate smoke and aerosol using standard ventilation machines
filtering device and available connecting components to
reduce the risk of OR staff infection [100]. This publication
even includes two videos, (1) how the system can be assem-
bled with standard OR equipment and (2) the demonstra-
tion during a total mesorectal excision procedure. Despite
regular instrument cleaning during surgery as well as deflat-
ing pneumoperitoneum prior to trocars as previously recom-
mended by colleagues from China and Italy [77], we
recommend adding such filters (mentioned above) to the
suction system both in laparoscopy and laparotomy
(Fig. 1 in Mintz et al. Ann Surg 2020, not included here)
[100].
3.2.2.3 Consider Gasless Laparoscopy
A nearly forgotten approach is performing laparoscopic
0surgery in the old-fashioned way, gasless for acute appen-
dicitis, acute cholecystitis and as a diagnostic tool.
3.2.2 Stoma > Anastomosis
The Royal College of Surgeons suggested that “stoma
formation rather than anastomosis to reduce the need for
unplanned post-operative critical care for complications”
be considered [17].
(4) Operation Room (OR)
!OR and Team
!COVID-19-testing and risk assessment
!Hot and cold OR and Team (high vs. low risk)
!Minimally required (senior) staff only
!Smoke extraction (and/or use bi-polar –smoke ;)
!Anesthesia
!Consider epidural/spinal/sedation
!In-/extubation within OR (consider aerosol box)
!No positive pressure ventilation
4.1 OR and Team
4.1.1 COVID-19-testing & risk assessment
The OR team should be tested and undergo a risk assess-
ment. In an evolving scenario it may be possible to select
OR staff with proven COVID-19 exposure to man the hot
ORs. When serology tests become available all theater staff
should undergo serology testing.
4.1.1HotandcoldORandTeam(highvs.lowrisk)
We recommend to use –if possible –a hot (H-OR) and cold
operation room (C-OR) and designating an area to differen-
tiate between operations on confirmed/suspicious COVID-
19 positive versus negative/non-suspicious patients. As
mentioned earlier, we are aware that there are infected
patients with negative testing. Within the H-OR area, fil-
tering of ventilation is important and –if possible negative
pressure operating rooms should be used. Emergency oper-
ations, on which no time delay due to life-threatening con-
dition occurs while to date no rapid COVID-19 test is
widely available, should always be operated within the H-
OR area. PPE is required for H-OR.
4.1.3 Minimally required (senior) staff only
In order to avoid any potential risk of infection for the
patient and the surgical staff and to minimize further
spread of SARS-CoV-2 virus, the personnel required to per-
form a necessary operation should be kept to a minimum
[101]. This strict implementation has several advantages.
ORs usually have positive pressure technology in the oper-
ating area (aseptic zone) and are separated from other areas
B.L.D.M. Brücher et al.: 4open 2020, 3,1 9

by doors. But when the doors to the anterooms are opened,
the well-directed laminar air flow will be disrupted and thus
particles and aerosols within the OR air can be swirled
which provides an explanation why it should be considered
to not apply a positive pressure ventilation in the OR under
this specific COVID-19 situation.
Recently, it was even recommended to set up a negative
pressure in the operating theatre to reduce virus dissemina-
tion beyond the OR [102]. Such an approach is recom-
mended since a long time, but the direction of airflow in
respiratory isolation rooms is often not correct [103]and
should be evaluated.
Nevertheless, air-turbulences are worse the more people
are in the OR with or without negative air ventilation.
Small expert teams of lead surgeons (N= 2), mechanical
devices to provide for optimal exposure, most experienced
surgical assistants (N= 2; one instrumentalist, one in-room
OR nurse) and anesthesiologist with one anesthesia nurse
(N= 2) act as a well-coordinated team, another reason to
minimize human movements within the aseptic zone. The
team should perform a huddle before surgery to talk
through the surgical and anesthesiological process and asso-
ciated risks and perform a time out at the end of surgery to
discuss postoperative risks and consequences as well as
quality of the COVID-19 risk management.
Hospital transmission was reported being responsible for
some 41% nosocomial SARS infections [15]. Even postpon-
ing and/or suspending postoperative visits were reported in
Singapore to minimize exposure and spread [102].
Protecting OR staff includes “surgeons, anesthetists,
and nurses and all possible transiting persons in the OR”
[77]. Limiting medical staff in the OR results in decreased
exposure and spread of COVID-19 with increased protec-
tion of health care teams. Only senior experienced staff
and not trainees or students should be involved in surgical
cases during this pandemic [52]. In some academic centers,
pathology service is included into the OR tract. We recom-
mend suspending this kind of pathology service during the
current outbreak.
4.1.4 Smoke extraction (and/or use bi-polar –smoke ;)
Major content has been reviewed in detail above (see
3. Rationale). Any form of electrosurgery produces smoke,
which should be minimized as much as possible decreasing
potential aerosolization and consecutive harming the
patient and/or OR staff. If available, bi-polar diathermy
including smoke suction/evacuators should be used.
The argument of the necessity of smoke extraction and/
or use of bi-polar tools which produce less smoke derives
from the evidence reviewed in the rationale for point (3).
Due to the high viral load in asymptomatic patients which
is comparable to symptomatic patients, and was implicated
that the very early transmission during the COVID-19
course differs significantly in terms of strict regulations
compared to the earlier SARS-CoV epidemic between
2002 and 2003 [104].
Screening 3363 individuals enrolling 246 individuals
with exhaled breath samples explored the value of respira-
tory droplet and aerosol routes of transmission with a
particular focus on coronaviruses, influenza viruses and rhi-
noviruses showed that surgical face masks significantly
reduced detection of influenza virus RNA in respiratory
droplets and coronavirus RNA in aerosols, with a trend
toward reduced detection of coronavirus RNA in respira-
tory droplets [105].
Furthermore, any airway procedures are now seen as
enhancing risk to the performer: intubation and ventilation
by anesthetists, and surgical procedures (including various
procedures by distinct surgical disciplines such as numerous
cancer surgery disciplines, cardiothoracic surgery, ENT,
eye, dermatology, emergency, endocrine surgery, general
surgery, gynecology, neurosurgery, orthopedics, pediatric
surgery, reconstructive and plastic surgery, surgical critical
care, transplantation surgery, trauma surgery and urology,
performing different surgeries, as well as laparoscopy, tho-
racoscopy and endoscopy) and this is why protection is
mandatory. Various specialties and especially ear nose
throat (ENT) surgeons are at high risk. The various specific
roles and responsibilities of all OR team members have been
reviewed by the ACS including the in- and extubation
within the operating room [106].
4.1 Anaesthesia
4.1.1 Consider epidural/spinal/sedation
Epidural combined spinal-epidural anesthesia was shown to
be safe for Cesarean delivery in parturients with COVID-
19, although the incidence of hypotension appeared exces-
sive [107]. This approach should certainly be used for inci-
sion and drainage of large abscesses, strangulated femoral
and inguinal hernia with low risk of bowel ischemia. Inade-
quate sedation may result in high risk during intubation in
case the patient gets agitated and/or has a coughing attack
with further risk of pathogen transmission.
4.1.2 Intubation and extubation within OR
(consider aerosol box)
“Bag valve-mask ventilation, non-invasive ventilation,
and intubation (in spontaneously breathing patients), may
create localized aerosol generation that can allow airborne
transmission to those closely involved in the procedure”
([108]reviewed in [109]). Extubation is associated with
increased coughing [110]. To minimize risks to health care
providers, in- and extubation should only be done –if
possible –within the OR.
An “aerosol box”consisting of a transparent plastic box
has been widely adapted for use in various ORs around the
world “that effectively shields a provider’sfacefroma
patient’s airway while allowing the provider to move his/
her arms freely to perform all necessary tasks during
endotracheal intubation”[111]. This aerosol box has been
developed pro bono by the anesthesiologist Hsien Yung
Lai from Mennonite Christian Hospital in Hua Lian,
Taiwan, and registered under a Creative Commons license.
Lateral ports have been added by Philippine ENT surgeons
for tracheostomy and upper aerodigestive tract surgery.
Virological analysis of COVID-19 patients showed
high pharyngeal virus shedding during the first week,
B.L.D.M. Brücher et al.: 4open 2020, 3,110

(on day 4: 7.11 108 RNA copies per throat swab) with
confirmation of active viral replication followed by serocon-
version after day 7 in up to 50% of patients (14 days in all)
[112]. This even serves as an argument that anaesthetists
only should be within the OR during intubation and/or
extubation.
4.1.3 No positive pressure ventilation
Positive airway pressure (continuous positive airway pres-
sure, CPAP/Bilevel Positive Airway Pressure, BiPAP) is
recommended to be avoided in procedures on COVID-19
patients due to the potential risk of pathogen transmission
over distances ([113]reviewed in [109]) although safe
reports are available ([114]reviewed in [109]).
Personal Protective Equipment (PPE)
!Low risk patients (LRP)
Double gloves, booties, surgical gown
FFP3 (N99) or P3 (N100) face mask
Face shield (+/googles), head cover
!High risk patients (HRP)
As in LRP plus overalls under surgical gown
Gowns (plastic ponchos)
Train dressing/undressing and supervision
In general, any kind of surgical procedure should include
wearing low risk PPE and as provided in Figure 3,and
high-risk PPE in case of emergency operations (without
testing), positively tested patients, and negatively tested
patients with a patient history of COVID-19 exposure.
Even non-symptomatic people can spread COVID-19
with high efficiency [115]. To date, there has been confusion
about the silent carrier transmission rate. A statistical
modeling approach to derive the delay-adjusted asymp-
tomatic proportion of infections estimated a silent carrier
rate of 17.9% [116] but the reality seems to be worse with
reported 46.5% non-symptomatic infected people during
the outbreak on the Diamond Princess Cruise ship [117].
This emphasizes the need for urgent aggressive protection
approaches to be implemented immediately. “The basic
reproduction rate was initially 4 times higher on-board com-
pared to the epicentre in Wuhan, China”and it was esti-
mated, that evacuating all Diamond Princess Passengers
and crew early during the outbreak “would have prevented
many more passengers and crew from infection”[118].
Based on the outbreak definition in accordance to
German Law –transmission of disease of two or more people
with a common cause probable or strongly suspected, §6
IfGS (= Infection Protection Act, In German: Infektionss-
chutzgesetz) –, the local health department (In German:
Gesundheitsamt) ordered a shutdown of a teaching hospital
in Germany and put it under quarantine (personal commu-
nication). For the firsttime,allpatientsplusallemployeesof
one German hospital (physicians, nurses, and health care
providers) were tested from Friday April 03 through
Sunday April 05, 2020. The teaching hospital’sproven
COVID-19 patient load on Friday, April 03, 2020 was:
34 patients, of whom 11 on intensive care unit (ICU) (on ven-
tilation), 1 on intermediate care unit(IMC), and 22 on infec-
tion ward; another 32 patients on another infection ward
were suspicious for COVID-19 with pending test results.
The following information is given anonymously by
ercentages only to protect the identity of the hospital in
Germany:
A total of 1,162 PCR test were performed, 774 in hospi-
tal staff, 260 in patients and in 128 physicians, resulting
into n= 19 COVID-19 positive individuals, resulting into
a silent carrier (asymptomatic) rate of 1.6%. Positive tested
individuals were isolated and the quarantine lifted.
These experiences underpin the necessity to strictly
follow the guidance of the RKI. Furthermore, it reveals,
that COVID-19 transmission can be low but it is impossible
to prevent in a hospital setting even when the system is not
completely overwhelmed with COVID-19 positive patients.
Therefore we recommend the testing as provided in Figure 3
out of protection reasons for patients and staff.
SARS-CoV-2 and SARS-CoV are both similar in size
(approximately 85 nm). Virus particles can penetrate five
surgical masks stacked together why it is recommended
that health care providers wear N95 (series # 1860) and
not the usual surgical masks [119]. Decreasing the rate of
virus particles to as small as 10–80 nm size by inhalation
can be decreased to a 5% penetration rate simply by using
N95 masks (series #1860) [120]. Protection management
must include eye protection (either goggles or full-face
shield) as well [121,122]. During the chaotic phases of
COVID-19 spread in Asia and Italy, any kind of eye protec-
tion was used, even personal goggles (model 9302-245;
Uvex, Germany).
PPE recommendation in treating critically ill COVID-
19 patients include using double gloves, booties, fluid-resis-
tant surgical gown, FFP3 (N99) or P3 (N100) face masks,
and eye protection face shield (+/googles), and a head
cover ([108]reviewed in [22,109]).
Furthermore, any health care provider above 65 years of
age with an increased co-morbidity risk (heart failure,
hypertension, lung disease, etc.) is at high risk in being part
of the H-OR, unless swab proven exposure to COVID-19
and a minimum 2 weeks isolation, or non-OR presence after
last symptoms.
We recommend differentiating low risk patients (LRP)
with no history and/or clinical and/or laboratory sign of
COVID-19 versus high risk patients (HRP) who have a pos-
itive COVID-19 test and/or history of COVID-19 exposure.
In HRP it is mandatory to wear PPE as in LRP patients
plus additional gowns such as plastic ponchos. The dressing
and undressing should be regularly done under trained
supervision, and in real time requires a buddy system to
be in place (much like scuba diving).
Based on what we currently know, patients and health
care providers are at high-risk for severe COVID-19 illness if
65 years of age or older, are living with home care or are
cared for in a long-term facility for the elderly. Further-
more, people of all ages with certain comorbidities are at
higher risk for severe illness, particularly if the underlying
medical conditions are not well controlled. Chronic lung dis-
B.L.D.M. Brücher et al.: 4open 2020, 3,1 11

ease or moderate to severe asthma, serious heart conditions,
people in immune compromised situation, including cancer
treatment, smoking, bone marrow or organ transplantation,
immune deficiencies, poorly controlled HIV or acquired
immune deficiency syndrome (AIDS), and prolonged use
of corticosteroids and other immune weakening medica-
tions, severe obesity (body mass index [BMI] of 40 or
higher), diabetes mellitus, chronic kidney disease, in need
of dialysis, and liver diseases are all such illnesses that have
to be taken into account and these patients need PPE from
patient admission to the OR, during the operation, and
after discharge via recovery room to the ward [22].
Discussion
Responding to the COVID-19 pandemic, countries
around the globe have increased hospital capacities, espe-
cially in terms of ICU beds and ventilators. Next to
patients, any health care provider needs to be protected
as well. It is imperative to functionally sustained healthcare
capacity to avoid a worst case scenario: widespread
COVID-19 transmission to OR staff increasing individual
risk to physicians and nurses and subsequent depletion of
essential human resources.
Our comprehensive and robust recommendation serves
as Pandemic Surgery Guidance during the exponential
spread of the COVID-19 or future similar outbreaks
throughout the world (Fig. 3).
Protective procedures in the operation room at Shang-
hai East Hospital, Tongji University, were provided in an
interview with Xiaohu Jiang, MD, PhD, Professor of Sur-
gery [75]. We review them here as each single step has
sound practical value:
1. Operations should be done in a negative pressure
OR with separate passage. Operation observation
is forbidden.
2. Operation sheets should be waterproof.
3. PPE shall be in accordance with level III protection
standards.
4. The wearing process of personnel on the operating
table (wearing two-layer surgical caps, three-layer
sterile gloves, two masks, two pairs of shoe covers,
two disposable surgical gowns, one medical protec-
tive clothing, one goggles, one protective screen and
one boot cover).
Step 1: Enter the OR, disinfect hands, change protec-
tive slippers, and enter the dressing room. Wash
hands in seven steps, change personal clothes, wear
hand washing clothes, remove personal articles such
as jewelry, watches, mobile phones, etc., and wear dis-
posable surgical caps.
Step 2: Wear medical protective mask and do a tight-
ness test.
Step 3: Wear goggles, shoe covers and disinfect hands.
Step 4: Enter the buffer zone after self-inspection.
Hand disinfection, inspection of medical protective
clothing (model, integrity, etc.), wearing disposable
medical protective clothing.
Step 5: Disinfect hands, wear the first layer of sterile
gloves, cover the cuff of protective clothing, and use
adhesive tape to fix the cuff if necessary.
Step 6: Wear disposable surgical cap.
Step 7: Wear disposable surgical mask.
Step 8: Wear disposable surgical clothes.
Step 9: Disinfect the hands, wear the second layer of
sterile gloves, and cover the cuff of disposable surgical
clothes.
Step 10: Wear a protective screen.
Step 11: Wear waterproof boot cover.
Step 12: Wear outer shoe cover.
Step 13: Disinfect the hands, confirm the correct don-
ning of clothing with the help of others, check whether
all PPE is complete, intact and appropriate in size,
ensure that the two layers of medical personnel are
tightly protected and the body is not exposed, and
enter the operating room after self-inspection in a
mirror.
Step 14: Disinfect surgical hands (disinfect hands and
wrists with hand sanitizer, i.e. the scope of the second
pair of gloves), and wear disposable sterile surgical
clothes.
Step 15: Wear the third layer of sterile gloves, and
cover the cuff of sterile surgical gown.
5. Measures to prevent aerosol transmission.
The smoke generated by the use of the electrosurgical
equipment will form aerosols. During the operation,
an aspirator can be used to absorb the smoke, but
the suction operation can also cause the generation
of aerosols. Therefore, it is recommended to reduce
the negative pressure suction operation during the
operation, and use the electrosurgical smoking device
to reduce the diffusion of aerosols.
Closed negative pressure suction system shall be used.
The disposable negative pressure suction bag shall be
added with effective chlorine containing disinfectant
of 5000 mg/L –10,000 mg/L before operation, and
sealed after operation, and treated as infectious med-
ical waste.
Endoscopic surgery should be minimized, because
there is no evidence to rule out whether the leakage
of pneumoperitoneum pressure in endoscopic surgery
contributes to aerosol transmission pathways, or
whether there is the possibility of increasing the risk
of infection of the operating personnel.
Summary
A consortium of scientists and clinicians from various
specialties provided a compact Pandemic Surgery Guidance
to serve as more practical guide during the exponential pan-
demic COVID-19 spread (Fig. 3). The guidance is relevant
for surgical procedures by distinct surgical disciplines such
as numerous cancer surgery disciplines, cardiothoracic
surgery, ENT, eye, dermatology, emergency, endocrine
surgery, general surgery, gynecology, neurosurgery, ortho-
pedics, pediatric surgery, reconstructive and plastic surgery,
surgical critical care, transplantation surgery, trauma
surgery and urology, performing different surgeries, as well
B.L.D.M. Brücher et al.: 4open 2020, 3,112

as laparoscopy, thoracoscopy and endoscopy. The present
Pandemic Surgery Guidance could even serve as the basis
for other future potential pathogen crises yet to come.
Suggestions and corrections from colleagues will be wel-
comed as we are all involved in a dynamically developing
process to increase our collective COVID-19 knowledge.
Nomenclature
AAO-HNS American Academy of Otolaryngology
Head and Neck Surgery
ACS American College of Surgeons
ACS-NSQIP American College of Surgeons National
Surgical Quality Improvement Pro-
gramme universal surgical risk calculator
AIDS Acquired immune deficiency syndrome
ANZHPBA Australian and New Zealand Hepatic,
Pancreatic and Biliary Association
ASA-PS American Society of Anesthesiologists
Physical Status Grading
BiPAP Bilevel Positive Airway Pressure
BMI Body mass index
BPV Bovine papillomavirus
CCI Charlson Comorbidity Index
CDC Center of Disease Control
CFR Case-fatality rate
CMS Centers for Medicare & Medicaid Services
C-OR Cold (low risk) operation room (OR)
COVID-19 Coronavirus disease 2019
CPAP Continuous positive airway pressure
CRP C-reactive protein
CT Computed tomography
EAES European Association for Endoscopic Sur-
gery
EASA Emergency Surgery Acuity Score
ECDC European Centre for Disease Prevention
and Control
FFP3 Filtering Face Pieces, class 3
FRSM Fluid resistant (Type IIR) surgical face
masks
HBV Hepatitis B virus
HIV Human Immunodeficiency Virus
HPV Human papillomavirus
HPV-6 Human papillomavirus type 6
HPV-11 Human papillomavirus type 11
H-OR Hot (high risk) operation room (OR)
HR Hazard ratio
ICU Intensive care unit
IL-6 Interleukin 6
IMC Intermediate care unit
LDH Lactate dehydrogenase
LRP Low risk patients
HRP High risk patients
MERS-CoV Middle East respiratory syndrome coron-
avirus
NAAT Nucleic acid amplification test
OR Operation room
PESAS Physiological Emergency Surgery Acuity
Score (PESAS)
PMRS Perioperative Mortality Risk Score
POSSUM Physiological and Operative Severity
Score for the Enumeration of Mortality
and Morbidity
PPE Personal Protective Equipment
PTCD Percutaneous transhepatic cholangiogra-
phy drainage
RCS Royal College of Surgeons of England
RKI Robert-Koch-Institute
RT-PCR Real-Time Polymerase Chain Reaction
SAGES Society of American Gastrointestinal and
Endoscopic Surgeons
SARS-CoV Severe Acute Respiratory Syndrome
Coronavirus
SARS-CoV-2 Severe Acute Respiratory Syndrome Coro-
na Virus 2
SAS Surgical Apgar Score
SMS Surgical Mortality Score
SORT Surgical Outcome Risk Tool
SRS Surgical Risk Scale
WHO World Health Organization
Supplementary material
Supplementary Material is available at https://www.
4open-sciences.org/10.1051/fopen/2020002/olm
Acknowledgments
The manuscript was created in very focused and fast
way (4 days). By this, we used a new way of a social med-
ium to receive and exchange material fast for review and
points of criticism. None of the colleagues was used to it,
but anyone who accepted that logistical way made it hap-
pen, to review, edit and change content fast (< 24 h). The
manuscript was supported by the Theodor-Billroth-
Academy
Ò
(TBA
Ò
) and INCORE, (International Consor-
tium of Research Excellence) of the (TBA
Ò
). We express
our gratitude to the discussions on the web group of the
Theodor-Billroth-Academy
Ò
(TBA
Ò
) on LinkedIn, the ex-
change with scientists at Researchgate.com, as well as per-
sonal exchanges with distinguished colleagues who
stimulated our thinking –we thank each one. The authors
highly acknowledge the extreme helpful and professional
fast peer-review process of the handling Editor as well as
of the excellent peer-reviewers.
Dedication
The authors dedicate the publication to all COVID-19
victimsaswellastoallphysicians,nursesandhealthcare
providers who gave everything they had and lost for the
benefit of their patients.
B.L.D.M. Brücher et al.: 4open 2020, 3,1 13

Conflict of Interest
The author reports the following conflict of interest:
Björn LDM Brücher is Editor-in-Chief in Life Sciences-
Medicine of 4open by EDP Sciences. Ijaz S Jamall, Marjan
Slak Rupnik, Ray Perkins and Bruno Zilberstein are Senior
Editorial Board members. The following colleagues are Edi-
torial members in Life Sciences-Medicine of 4open by EDP
Sciences: Jochen Salber, Avraham Rivkind, Jose Florencio
F Lapeña Jr., Rainer Kube, Michael Scherer, Jose da Costa,
Rainer Lück, Mesut Tez, Selman Sökmen, Edouard Mat-
evossian, Nelson Elias, Grzegorz Wallner, and Mohammad
Kermansaravi. The authors, of their own initiative, sug-
gested publishing the manuscript as a Rapid Publication
with online reviewing including to the Managing Editorial
to perform a transparent peer-review of their submittals.
No author took any action to influence the standard sub-
mission and peer-review process, and all report no conflict
of interest. The authors alone are responsible for the con-
tent and writing of the manuscript. This manuscript con-
tains original material that has not previously been
published. The idea for this manuscript came from the first
author. After a structure was created, INCORE members,
such as Björn LDM Brücher, Ijaz S Jamall, and Marjan
Slak Rupnik revised it and the body text was created. Each
single author contributed to acquisition and/or analysis and
interpretation of data. Every single author read, reviewed
and edited the manuscript. All authors contributed to the
manuscript and its discussion and summary and approved
the final manuscript. Each author agrees to be accountable
for all aspects of the work. The Uniformed Services Univer-
sity of the Health Sciences author reported no proprietary
or commercial interest in any product mentioned or concept
discussed in this article. The opinions or assertions con-
tained herein are the private ones of the author and are
not to be construed as official or reflecting the views of
the Department of Defense, the Uniformed Services Univer-
sity of the Health Sciences or any other agency of the U.S.
Government.
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Cite this article as: Brücher B.L.D.M, Nigri G, Tinelli A, Lape~
na Jr J.F.F, Espin-Basany E, et al. 2020. COVID-19: Pandemic
surgery guidance. 4open, 3,1.
B.L.D.M. Brücher et al.: 4open 2020, 3,1 19