Abstract
Background
Methods
Results
Conclusion
Introduction
- Di Marzo F.
- Sartelli M.
- Cennamo R.
- et al.
Elective surgery cancellations due to the COVID-19 pandemic: global predictive modelling to inform surgical recovery plans [e-pub ahead of print].
Methods
Setting
Nederlandse Federatie voor Medisch Specialisten. Pre-operative work-up for COVID-19 infection in asymptomatic patients scheduled for surgery under general anesthesia. 2020. https://www.nvtnet.nl/sites/thorax.productie.medonline.nl/files/bijlagen/Practice%20Guideline%20Preoperative%20work%20up%20on%20possible%20COVID-19%20infection%20in%20asymptomatic%20patients%20V3.0.pdf. Accessed April 2020.
Inclusion and exclusion criteria
Data acquisition and management
Study parameters
Risk stratification: Risk stratification before elective surgery.
Study end points
Statistical analysis
Results
Description of the cohort

Unmatched patients | Propensity score-matched patients | |||
---|---|---|---|---|
SARS-CoV-2 positive patients n = 161 | SARS-CoV-2 negative patients n = 342 | SARS-CoV-2 positive patients n = 123 | SARS-CoV-2 negative patients n = 196 | |
Age category–no (%) | ||||
<50 y | 14 (8.7) | 89 (26.0) | 13 (10.6) | 19 (9.7) |
50–<70 y | 51 (31.7) | 138 (40.4) | 47 (38.2) | 80 (40.8) |
≥70 y | 95 (59.0) | 115 (33.6) | 63 (51.2) | 97 (49.5) |
Female sex–no (%) | 72 (44.7) | 161 (47.1) | 56 (45.5) | 93 (47.4) |
BMI–no (%) | ||||
<18.5 | 7 (4.3) | 29 (8.5) | 6 (4.9) | 10 (5.1) |
18.5–<25 | 49 (30.4) | 117 (34.2) | 41 (33.3) | 65 (33.2) |
25–<30 | 46 (28.6) | 112 (32.7) | 39 (31.7) | 66 (33.7) |
30–<35 | 32 (19.6) | 49 (14.3) | 24 (19.5) | 38 (19.4) |
35–<40 | 12 (7.5) | 21 (6.1) | 10 (8.1) | 15 (7.7) |
≥40 | 5 (3.1) | 3 (0.9) | 3 (2.4) | 2 (1.0) |
Missing | 10 (6.2) | 11 (3.2) | 0 | 0 |
Current smoker–no (%) | 18 (11.2) | 47 (13.7) | 18 (14.6) | 33 (16.8) |
Missing | 33 (20.5) | 71 (20.8) | 0 | 0 |
Diabetes–no (%) | 44 (27.3) | 42 (12.3) | 22 (18) | 35 (18) |
Hypertension–no (%) | 80 (49.7) | 105 (30.7) | 53 (43.1) | 87 (44.4) |
Missing | 0 (0.0) | 13 (3.8) | 0 | 0 |
Congestive heart failure–no (%) | 13 (8.1) | 19 (5.6) | 8 (6.5) | 13 (6.6) |
Myocardial infarct–no (%) | 21 (13.0) | 24 (7.0) | 12 (9.8) | 19 (9.7) |
Peripheral vascular disease–no (%) | 26 (16.1) | 40 (11.7) | 16 (13) | 27 (14) |
Chronic pulmonary disease–no (%) | 20 (12.4) | 26 (7.6) | 10 (8.1) | 20 (10) |
CVA–no (%) | 24 (14.9) | 31 (9.1) | 13 (11) | 21 (11) |
Chronic renal disease–no (%) | 22 (13.7) | 25 (7.3) | 10 (8.1) | 16 (8.2) |
Cancer–no (%) | 30 (18.6) | 123 (36.0) | 27 (22) | 47 (24) |
Transplant–no (%) | 1 (0.6) | 7 (2.0) | 1 (0.8) | 1 (0.5) |
Missing | 2 (1.2) | 2 (0.6) | 0 | 0 |
Immunosuppression–no (%) | 10 (6.2) | 17 (5.0) | 9 (7.3) | 10 (5.1) |
Missing | 0 | 6 (1.8) | 0 | 0 |
ECOG score | ||||
0–1 | 93 (57.8) | 288 (84.2) | 92 (75) | 155 (79) |
2 | 26 (16.1) | 29 (8.5) | 21 (17) | 25 (13) |
3–4 | 30 (18.6) | 18 (5.3) | 10 (8.1) | 16 (8.2) |
Missing | 12 (7.5) | 7 (2.0) | 0 | 0 |
Charlson comorbidity index–median (IQR) | 4 (2–7) | 4 (2–6) | 4 (2–6) | 4 (2–6) |
Missing | 0 (0.0) | 1 (0.3) | 0 | 0 |
ASA classification–no (%) | ||||
I–II | 60 (37.3) | 169 (49.4) | 54 (44) | 87 (44) |
III–IV | 97 (60.2) | 170 (49.7) | 69 (56) | 109 (56) |
Missing | 4 (2.5) | 3 (0.9) | 0 | 0 |
Anesthesia–no (%) | ||||
General | 118 (73.3) | 291 | 98 (80) | 156 (80) |
Other (including spinal) | 43 (26.7) | 51 | 25 (20) | 40 (20) |
Missing | 0 (0.0) | 0 (0.0) | 0 | 0 |
Type of operation–no (%) | ||||
Elective | 87 (54.0) | 252 (73.7) | 76 (62) | 131 (67) |
Emergency | 73 (45.3) | 84 (24.6) | 47 (38) | 65 (33) |
Missing | 1 (0.6) | 6 (1.8) | 0 | 0 |
Surgical risk score–no (%) | ||||
1–2 | 42 (26.1) | 72 (21.1) | 35 (29) | 48 (25) |
3 | 64 (39.8) | 135 (39.5) | 47 (38) | 86 (44) |
4 | 36 (22.4) | 100 (29.2) | 31 (25) | 48 (25) |
5 | 10 (6.2) | 31 (9.1) | 10 (8.1) | 14 (7.1) |
Missing | 9 (5.6) | 4 (1.2) | 0 | 0 |
SARS-CoV-2 positive patients

SARS-CoV-2 positive patients Survivors n = 135 | SARS-CoV-2 positive patients Nonsurvivors n = 26 | P value | |
---|---|---|---|
Patient characteristics | |||
Age category–no (%) | <.001 | ||
<50 y | 14 (10.4) | 0 (0.0) | |
50–<70 y | 49 (36.6) | 2 (7.7) | |
≥70 y | 71 (53.0) | 24 (92.3) | |
Female sex–no (%) | 62 (45.9) | 10 (38.5) | .63 |
BMI–no (%) | .93 | ||
<18.5 | 5 (3.7) | 2 (7.7) | |
18.5–<25 | 40 (29.6) | 9 (34.6) | |
25–<30 | 40 (29.6) | 6 (23.1) | |
30–<35 | 26 (19.3) | 6 (23.1) | |
35–<40 | 10 (7.4) | 2 (7.7) | |
≥40 | 4 (3.0) | 1 (3.8) | |
Current smoker–no (%) | 14 (10.4) | 4 (15.4) | .71 |
Diabetes–no (%) | 32 (23.7) | 12 (46.2) | .04 |
Hypertension–no (%) | 64 (47.4) | 16 (61.5) | |
Congestive heart failure–no (%) | 7 (5.2) | 6 (23.1) | |
Myocardial infarct–no (%) | 13 (9.6) | 8 (30.3) | .27 |
Peripheral vascular disease–no (%) | 16 (11.9) | 10 (38.5) | .002 |
Chronic pulmonary disease–no (%) | 14 (10.4) | 6 (23.1) | .14 |
CVA–no (%) | 18 (13.3) | 6 (23.1) | .33 |
Chronic renal disease–no (%) | 15 (11.1) | 7 (26.9) | .07 |
Cancer–no (%) | 26 (19.3) | 4 (15.4) | .85 |
Transplant–no (%) | 0 (0.0) | 1 (3.8) | 1.00 |
Immunosuppression–no (%) | 9 (6.7) | 1 (3.8) | .92 |
ECOG score | .002 | ||
0–1 | 84 (62.2) | 9 (34.6) | |
2 | 22 (16.3) | 4 (15.4) | |
3–4 | 19 (14.1) | 11 (42.3) | |
Charlson comorbidity index–median (IQR) | 4.0 (2.0–6.0) | 6.5 (4.0–8.9) | .001 |
Surgery characteristics | |||
ASA classification–no (%) | .02 | ||
I–II | 56 (41.5) | 4 (15.4) | |
III–IV | 75 (55.6) | 22 (84.6) | |
Anesthesia–no (%) | .79 | ||
General | 100 (74.1) | 18 (69.2) | |
Other (including spinal) | 35 (25.9) | 8 (30.8) | |
Type of operation–no (%) | 1.00 | ||
Elective | 73 (54.1) | 14 (53.8) | |
Emergency | 61 (45.2) | 12 (46.2) | |
Surgical risk score–no (%) | .06 | ||
1–2 | 39 (38.9) | 3 (11.5) | |
3 | 47 (34.8) | 17 (65.4) | |
4 | 31 (23.0) | 5 (19.2) | |
5 | 9 (6.7) | 1 (3.8) | |
SARS-CoV-2 characteristics | |||
Timing of diagnosis–no (%) | .001 | ||
Preoperative | 67 (49.6) | 2 (7.7) | |
Postoperative | 68 (50.4) | 24 (92.3) | |
Symptomatology–no (%) | 1.00 | ||
Asymptomatic | 9 (6.7) | 2 (7.7) | |
≥1 symptom | 117 (86.7) | 23 (88.5) |
Primary outcome
Unmatched patients | P value | Propensity score-matched patients | P value | |||
---|---|---|---|---|---|---|
SARS-CoV-2 positive patients n = 161 | SARS-CoV-2 negative patients n = 342 | SARS-CoV-2 positive patients n = 123 | SARS-CoV-2 negative patients n = 196 | |||
30-d postoperative mortality | ||||||
30-d follow-up–no (%) | <.001 | <.001 | ||||
Alive at hospital | 26 (16.1) | 25 (7.3) | 21 (17.1) | 13 (6.6) | ||
Alive at rehabilitation | 35 (21.7) | 21 (6.1) | 25 (20.3) | 16 (8.2) | ||
Alive at home | 74 (46.0) | 282 (82.5) | 62 (50.4) | 158 (80.6) | ||
Deceased | 26 (16.2) | 14 (4.1) | 15 (12.2) | 9 (4.6) | ||
30-d postoperative complications | ||||||
Number of complications per patient, median (IQR) | 1 (0–3) | 0 (0–1) | <.0001 | 1 (0–2) | 0 (0–1) | <.001 |
Comprehensive complication index, median (IQR) | 20.9 (0–42.7) | 0 (0–20.9) | <.0001 | 20.9 (0–39.5) | 0 (0–12.2) | <.0001 |
Pulmonary complications–no (%) | 39 (24.2) | 11 (3.2) | <.0001 | 25 (20.3) | 6 (3.1) | <.0001 |
Thromboembolic complications–no (%) | 11 (6.8) | 1 (0.3) | <.0001 | 8 (6.5) | 1 (0.5) | .004 |
Hemorrhagic complications– no (%) | 22 (13.6) | 28 (8.2) | .052 | 16 (9.9) | 20 (10.2) | .49 |
Infectious complications–no (%) | 13 (8.1) | 27 (7.8) | .97 | 11 (8.9) | 12 (6.1) | .42 |
Secondary outcomes
Discussion
- Worldometer Age
Nederlandse Federatie voor Medisch Specialisten. Pre-operative work-up for COVID-19 infection in asymptomatic patients scheduled for surgery under general anesthesia. 2020. https://www.nvtnet.nl/sites/thorax.productie.medonline.nl/files/bijlagen/Practice%20Guideline%20Preoperative%20work%20up%20on%20possible%20COVID-19%20infection%20in%20asymptomatic%20patients%20V3.0.pdf. Accessed April 2020.
Leidraad COVID-19 coagulopathie.
Conflict of interest/Disclosures
Funding/Support
First Name | Middle Name(S) | Last Name | Affiliation |
---|---|---|---|
Djamila | Boerma | Department of Surgery, Antonius Ziekenhuis, Nieuwegein, The Netherlands | |
Sarah | L | Gerritsen | Department of Surgery, Antonius Ziekenhuis, Nieuwegein, The Netherlands |
Wout | van der Meij | Department of Surgery, Bernhoven, Uden, the Netherlands | |
André | S | van Petersen | Department of Surgery, Bernhoven, Uden, the Netherlands |
Charles | T | Stevens | Department of Surgery, Bernhoven, Uden, the Netherlands |
Marc | van Sambeek | Department of Surgery, Catharina Ziekenhuis, Eindhoven, the Netherlands | |
Marleen | Hölscher | Department of Surgery, Catharina Ziekenhuis, Eindhoven, the Netherlands | |
Apollo | Pronk | Department of Surgery, Diakonessenhuis, Utrecht, the Netherlands | |
Wouter | J | Bakker | Department of Surgery, Diakonessenhuis, Utrecht, the Netherlands |
Patrick | WHE | Vriens | Department Of Surgery, Elisabeth Tweesteden Ziekenhuis, Tilburg, The Netherlands |
Thymen | Houwen | Department of Surgery, Elisabeth Tweesteden Ziekenhuis, Tilburg, the Netherlands | |
Johannes | A | Wegdam | Elkerliek, Helmond, the Netherlands |
Tammo | S | de Vries Reilingh | Elkerliek, Helmond, the Netherlands |
Ellis | Schipper | Elkerliek, Helmond, the Netherlands | |
Pascal | HE | Teeuwen | Elkerliek, Helmond, the Netherlands |
Tessa | M | van Ginhoven | Department of Surgery, Erasmus Universitair MC, Rotterdam, the Netherlands |
Charlotte | L | Viëtor | Department of Surgery, Erasmus Universitair MC, Rotterdam, the Netherlands |
Mark | JW | van der Oest | Department of Plastic, Reconstructive and Hand Surgery, Erasmus MC, Rotterdam, The Netherlands Department of Rehabilitation Medicine, Erasmus MC, Rotterdam, The Netherlands Hand and Wrist Center, Xpert Clinic, the Netherlands |
Sarah | L | Gans | Department of Surgery, Gelre Ziekenhuis, Apeldoorn, the Netherlands |
Peter | van Duijvendijk | Department of Surgery, Gelre Ziekenhuis, Apeldoorn, the Netherlands | |
Tanneke | Herklots | Department of Surgery, Gelre Ziekenhuis, Apeldoorn, the Netherlands | |
Tom | de Hoop | Department of Surgery, Gelre Ziekenhuis, Apeldoorn, the Netherlands | |
Michelle | R | de Graaff | Department of Surgery, Gelre Ziekenhuis, Apeldoorn, the Netherlands |
Didi | AM | Sloothaak | Department of Surgery, Gelre Ziekenhuis, Apeldoorn, the Netherlands |
Marieke | J | Bolster-van Eenenennaam | Department of Surgery, Gelre Ziekenhuis, Apeldoorn, the Netherlands |
Jedidja | Baaij | Department of Surgery, Gelre Ziekenhuis, Apeldoorn, the Netherlands | |
Maarten | Vermaas | Department of Surgery, IJsselland Ziekenhuis, Capelle aan den IJssel, the Netherlands | |
Kelly | R | Voigt | Department of Surgery, IJsselland Ziekenhuis, Capelle aan den IJssel, the Netherlands |
Gijs | A | Patijn | Department of Surgery, Isala Clinics, Zwolle, the Netherlands |
Amarins | TA | Bransma | Department of Surgery, Isala Clinics, Zwolle, the Netherlands |
Wouter | KG | Leclercq | Department of Surgery, Maxima Medisch Centrum, Veldhoven, the Netherlands |
Julie | ML | Sijmons | Department of Surgery, Maxima Medisch Centrum, Veldhoven, the Netherlands |
Martine | Uittenbogaart | Department of Surgery, Maxima Medisch Centrum, Veldhoven, the Netherlands | |
Paul | M | Verheijen | Department of Surgery, Meander Medisch Centrum, Amersfoort & Baarn, the Netherlands |
Thijs | A | Burghgraef | Department of Surgery, Meander Medisch Centrum, Amersfoort & Baarn, the Netherlands |
Marloes | Emous | Department of Surgery, Medical Center Leeuwarden, Leeuwarden, the Netherlands | |
Ralph | Poelstra | Department of Surgery, Medical Center Leeuwarden, Leeuwarden, the Netherlands | |
Manon | Teunissen | Department of Surgery, Medical Center Leeuwarden, Leeuwarden, the Netherlands | |
Herman | Frima | Department of Surgery, Noordwest Ziekenhuisgroep, Alkmaar & Den Helder, the Netherlands | |
Said | Bachiri | Department of Surgery, Noordwest Ziekenhuisgroep, Alkmaar & Den Helder, the Netherlands | |
Lennaert | CB | Groen | Department of Surgery, Noordwest Ziekenhuisgroep, Alkmaar & Den Helder, the Netherlands |
Philip | R | de Reuver | Department of Surgery, Radboud University Medical Center, Nijmegen, the Netherlands |
Floris | M | Thunnissen | Department of Surgery, Radboud University Medical Center, Nijmegen, the Netherlands |
Britt | AM | Vermeulen | Department of Surgery, Radboud University Medical Center, Nijmegen, the Netherlands |
Anna | Groen | Department of Surgery, Radboud University Medical Center, Nijmegen, the Netherlands | |
Ramon | RJP | van Eekeren | Department of Surgery, Rijnstate, Arnhem, the Netherlands |
Ernst | J | Spillenaar Bilgen | Department of Surgery, Rijnstate, Arnhem, the Netherlands |
Niels | J | Harlaar | Department of Surgery, Rode Kruis Ziekenhuis, Beverwijk, the Netherlands Department of Surgery, Noordwest Ziekenhuisgroep, Alkmaar & Den Helder, the Netherlands |
Frederik | HW | Jonker | Department of Surgery, Rode Kruis Ziekenhuis, Beverwijk, the Netherlands Department of Surgery, Noordwest Ziekenhuisgroep, Alkmaar & Den Helder, the Netherlands |
Sjirk | W | van der Burg | Department of Surgery, Rode Kruis Ziekenhuis, Beverwijk, the Netherlands |
Lisanne | AE | Posma-Bouman | Department of Surgery, Slingeland Ziekenhuis, Doetinchem, the Netherlands |
Steven | J | Oosterling | Department of Surgery, Spaarne Gasthuis, Haarlem & Hoofddorp, the Netherlands |
Josephine | Franken | Department of Surgery, Spaarne Gasthuis, Haarlem & Hoofddorp, the Netherlands | |
David | R | Nellensteijn | Department of Surgery, Curacao Medical Center, Willemstad, Curaçao |
Elena Argia Bianca | Bensi | Department of Surgery, Curacao Medical Center, Willemstad, Curaçao | |
Wim | van den Broek | Department of Surgery, Sint Anna Ziekenhuis, Geldrop, the Netherlands | |
Eduard | R | Hendriks | Department of Surgery, Tergooi, Hilversum & Blaricum, The Netherlands |
Anna | AW | van Geloven | Department of Surgery, Tergooi, Hilversum & Blaricum, The Netherlands |
Schelto | Kruijff | Department of Surgery, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands | |
Jean-Paul | P.M. | de Vries | Department of Surgery, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands |
Pieter | J | Steinkamp | Department of Surgery, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands |
Pascal | KC | Jonker | Department of Surgery, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands |
Willemijn | Y | van der Plas | Department of Surgery, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands |
Wouter | FW | Bierman | Department of Internal Medicine and Infectious Diseases, University of Groningen, University |
Medical Center Groningen, Groningen, the Netherlands | |||
Michel | MRF | Struys | Department of Anesthesiology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands |
Yester | F | Janssen | Department of Surgery, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands |
Gooitzen | M | van Dam | Deptartments of surgery, nuclear medicine and molecular imaging, medical imaging center, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands |
Frank | FA | IJpma | Department of Surgery, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands |
Claire | van der Riet | Department of Surgery, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands | |
Elisabeth | A | Feitsma | Department of Surgery, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands |
Kirsten | F | Ma | Department of Surgery, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands |
Simone | F | Kleiss | Department of Surgery, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands |
Milan | C | Richir | Department of Surgery, University Medical Center Utrecht, Utrecht, the Netherlands |
Menno | R | Vriens | Department of Surgery, University Medical Center Utrecht, Utrecht, the Netherlands |
Mando | D | Filipe | Department of Surgery, University Medical Center Utrecht, Utrecht, the Netherlands |
Frank | C | den Boer | Department of Surgery, Zaans Medisch Centrum, Zaandam, the Netherlands |
Nicole | AM | Dekker | Department of Surgery, Zaans Medisch Centrum, Zaandam, the Netherlands |
Tim | Verhagen | Department of Surgery, Ziekenhuisgroep Twente, Almelo & Hengelo, the Netherlands | |
Floor | ter Brugge | Department of Surgery, Ziekenhuisgroep Twente, Almelo & Hengelo, the Netherlands | |
Emmanuel | AGL | Lagae | Department of Surgery, Zorgsaam Zeeuws Vlaanderen, Terneuzen, the Netherlands |
Evert-Jan | G | Boerma | Zuyderland Medical Center, Heerlen & Sittard/Geleen, the Netherlands |
Donald | Schweitzer | Zuyderland Medical Center, Heerlen & Sittard/Geleen, the Netherlands | |
Mark | HF | Keulen | Zuyderland Medical Center, Heerlen & Sittard/Geleen, the Netherlands |
Shirley | Ketting | Zuyderland Medical Center, Heerlen & Sittard/Geleen, the Netherlands |
Acknowledgments
Supplementary data


- Supplemental Table I
- Supplemental Table II
- Supplemental Table III
References
- COVID-19 Map.
- Recommendations for general surgery activities in a pandemic scenario (SARS-CoV-2)[e-pub ahead of print].Br J Surg. 2020; (Accessed April 23, 2020)https://doi.org/10.1002/bjs.11652
- Elective surgery cancellations due to the COVID-19 pandemic: global predictive modelling to inform surgical recovery plans [e-pub ahead of print].Br J Surg. 2020; (Accessed May 12, 2020)https://doi.org/10.1002/bjs.11746
- Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study.Lancet. 2020; 396: 27-38
- National surgical mortality audit may be associated with reduced mortality after emergency admission.ANZ J Surg. 2017; 87: 830-836
- Postoperative mortality in the Netherlands: a population-based analysis of surgery-specific risk in adults.Anesthesiology. 2010; 112: 1105-1115
- Factors associated with surgical mortality and complications among patients with and without coronavirus disease 2019 (COVID-19) in Italy.JAMA Surg. 2020; 155: 1-14
Nederlandse Federatie voor Medisch Specialisten. Pre-operative work-up for COVID-19 infection in asymptomatic patients scheduled for surgery under general anesthesia. 2020. https://www.nvtnet.nl/sites/thorax.productie.medonline.nl/files/bijlagen/Practice%20Guideline%20Preoperative%20work%20up%20on%20possible%20COVID-19%20infection%20in%20asymptomatic%20patients%20V3.0.pdf. Accessed April 2020.
- Research electronic data capture (REDCap)-A metadata-driven methodology and workflow process for providing translational research informatics support.J Biomed Inform. 2009; 42: 377-381
- Overheid.nl. Covid-19 cumulatieve aantallen per gemeente | Data overheid.https://data.overheid.nl/dataset/11508-covid-19-aantallen-gemeente-cumulatief#downloadable-filesDate: 2020Date accessed: June 15, 2020
- A new method of classifying prognostic comorbidity in longitudinal studies: development and validation.J Chronic Dis. 1987; 40: 373-383
- Risk stratification: Risk stratification before elective surgery.https://www.uclahealth.org/anes/risk-stratificationDate accessed: May 28, 2020
- Classification of surgical complications a new proposal with evaluation in a cohort of 6336 patients and results of a survey.Ann Surg. 2004; 240: 205-213
- The comprehensive complication index a novel and more sensitive endpoint for assessing outcome and reducing sample size in randomized controlled trials.Ann Surg. 2014; 260 (discussion 762-763): 757-762
Little RJA, Rubin DB. Statistical Analysis with Missing Data. 2nd ed. Hoboken (NJ): John Wiley & Sons, Inc; 2002.
- mice: multivariate imputation by chained equations in R.J Stat Softw. 2011; 45: 1-67
- MatchIt: nonparametric preprocessing for parametric causal inference.J Stat Softw. 2011; 42: 1-28
- sex, existing conditions of COVID-19– cases and deaths.https://www.worldometers.info/coronavirus/coronavirus-age-sex-demographics/#pre-existing-conditionsDate: 2020Date accessed: June 19, 2020
- Clinical characteristics and outcomes of patients undergoing surgeries during the incubation period of COVID-19 infection.EClinicalMedicine. 2020; 0: 100331
- Mitigating the risks of surgery during the COVID-19 pandemic.Lancet. 2020; 396: 2-3
- The effect of anaesthesia and surgery on plasma cytokine production.Anaesthesia. 1999; 54: 733-738
- Incidences and variations of hospital acquired venous thromboembolism in Australian hospitals: a population-based study.BMC Health Serv Res. 2016; 16: 511
- Coagulation abnormalities and thrombosis in patients with COVID-19.Lancet Haematol. 2020; 7: e428-e440
- Incidence of venous thromboembolism in hospitalized patients with COVID-19.J Thromb Haemost. 2020; 18: 1995-2002
- Incidence of thrombotic complications in critically ill ICU patients with COVID-19.Thromb Res. 2020; 191: 145-147
- The incubation period of coronavirus disease 2019 (COVID-19) from publicly reported confirmed cases: estimation and application.Ann Intern Med. 2020; 172: 577-582
- Clinical characteristics of coronavirus disease 2019 in China.N Engl J Med. 2020; 382: 1708-1720
- Leidraad COVID-19 coagulopathie.https://www.demedischspecialist.nl/nieuws/leidraad-covid-19-coagulopathieDate: 2020Date accessed: June 21, 2020
Article info
Publication history
Footnotes
This article was submitted on behalf of the Dutch Surgical COVID-19 Research Collaborative (please refer to Supplemental File 1 for the list of collaborators and contact details)
Pascal K.C. Jonker, Willemijn Y. van der Plas, and Pieter J. Steinkamp contributed equally to this work.
Identification
Copyright
User license
Creative Commons Attribution (CC BY 4.0) |
Permitted
- Read, print & download
- Redistribute or republish the final article
- Text & data mine
- Translate the article
- Reuse portions or extracts from the article in other works
- Sell or re-use for commercial purposes
Elsevier's open access license policy