Peri-operative SARS-CoV-2 infection increases postoperative mortality. The aim of this study was to determine the optimal duration of planned delay before surgery in patients who have had SARS-CoV-2 infection. This international, multicentre, prospective cohort study included patients undergoing elective or emergency surgery during October 2020. Surgical patients with pre-operative SARS-CoV-2 infection were compared with those without previous SARS-CoV-2 infection. The primary outcome measure was 30-day postoperative mortality. Logistic regression models were used to calculate adjusted 30-day mortality rates stratified by time from diagnosis of SARS-CoV-2 infection to surgery. Among 140,231 patients (116 countries), 3127 patients (2.2%) had a pre-operative SARS-CoV-2 diagnosis. Adjusted 30-day mortality in patients without SARS-CoV-2 infection was 1.5% (95%CI 1.4-1.5). In patients with a pre-operative SARS-CoV-2 diagnosis, mortality was increased in patients having surgery within 0-2 weeks, 3-4 weeks and 5-6 weeks of the diagnosis (odds ratio (95%CI) 4.1 (3.3-4.8), 3.9 (2.6-5.1) and 3.6 (2.0-5.2), respectively). Surgery performed ≥ 7 weeks after SARS-CoV-2 diagnosis was associated with a similar mortality risk to baseline (odds ratio (95%CI) 1.5 (0.9-2.1)). After a ≥ 7 week delay in undertaking surgery following SARS-CoV-2 infection, patients with ongoing symptoms had a higher mortality than patients whose symptoms had resolved or who had been asymptomatic (6.0% (95%CI 3.2-8.7) vs. 2.4% (95%CI 1.4-3.4) vs. 1.3% (95%CI 0.6-2.0), respectively). Where possible, surgery should be delayed for at least 7 weeks following SARS-CoV-2 infection. Patients with ongoing symptoms ≥ 7 weeks from diagnosis may benefit from further delay.

SARS-CoV-2 has been associated with an increased rate of venous thromboembolism in critically ill patients. Since surgical patients are already at higher risk of venous thromboembolism than general populations, this study aimed to determine if patients with peri-operative or prior SARS-CoV-2 were at further increased risk of venous thromboembolism. We conducted a planned sub-study and analysis from an international, multicentre, prospective cohort study of elective and emergency patients undergoing surgery during October 2020. Patients from all surgical specialties were included. The primary outcome measure was venous thromboembolism (pulmonary embolism or deep vein thrombosis) within 30 days of surgery. SARS-CoV-2 diagnosis was defined as peri-operative (7 days before to 30 days after surgery); recent (1-6 weeks before surgery); previous (≥7 weeks before surgery); or none. Information on prophylaxis regimens or pre-operative anti-coagulation for baseline comorbidities was not available. Postoperative venous thromboembolism rate was 0.5% (666/123,591) in patients without SARS-CoV-2; 2.2% (50/2317) in patients with peri-operative SARS-CoV-2; 1.6% (15/953) in patients with recent SARS-CoV-2; and 1.0% (11/1148) in patients with previous SARS-CoV-2. After adjustment for confounding factors, patients with peri-operative (adjusted odds ratio 1.5 (95%CI 1.1-2.0)) and recent SARS-CoV-2 (1.9 (95%CI 1.2-3.3)) remained at higher risk of venous thromboembolism, with a borderline finding in previous SARS-CoV-2 (1.7 (95%CI 0.9-3.0)). Overall, venous thromboembolism was independently associated with 30-day mortality ). In patients with SARS-CoV-2, mortality without venous thromboembolism was 7.4% (319/4342) and with venous thromboembolism was 40.8% (31/76). Patients undergoing surgery with peri-operative or recent SARS-CoV-2 appear to be at increased risk of postoperative venous thromboembolism compared with patients with no history of SARS-CoV-2 infection. Optimal venous thromboembolism prophylaxis and treatment are unknown in this cohort of patients, and these data should be interpreted accordingly.

BackgroundBiopsy of the temporal artery is considered fundamental to making the diagnosis of temporal arteritis. Besides carrying a significant false negative rate owing to skip lesions, the procedure has a small risk of significant complications including facial nerve injury1, scalp necrosis2 and stroke3. The procedure may be contraindicated by delay in undertaking the biopsy from commencement of treatment, patient's wishes or bleeding diathesis.ObjectivesTo study the incidence of biopsy-proven temporal arteritis in the population surrounding Chesterfield Royal Hospital, United Kingdom.MethodsA retrospective review of 235 consecutive patients who underwent a temporal artery biopsy in Chesterfield Royal Hospital from January 2009 to January 2015. Study variables included age at diagnosis, gender, CRP, ESR and ALP results prior to treatment.ResultsAmong these 235 patients who underwent temporal artery biopsy, the mean age of those in the biopsy-positive group, 76.4 years (95% CI 73.8, 79.0), was higher than that of those in the biopsy-negative group, 70.4 (95% CI 69.0, 71.8). Using a two sample t-test, this generated a p value of 0.0002. A logistic regression model showed there is a statistically significant increase in the odds of a positive temporal artery biopsy of 1.072487 (CI 1.03045 to 1.116238) for every year increase of age, in addition to an odds increase of 1.022069 (CI 1.011327 to 1.032925) for every 1mm/hr increase in ESR. There was no statistical correlation between biopsy positive and biopsy-negative groups for CRP or ALP level; but a number patients had no CRP (97) or ALP (71) measured prior to diagnosis.ConclusionsOur results show there is a significant increase of likelihood of a positive temporal artery biopsy as the patient's age increases and the higher the value of ESR. Given a large enough sample, these results suggest that a scoring system may be created which can attempt to predict the likelihood of a positive temporal artery biopsy. This may be useful for patients in which temporal arteritis is suspected and biopsy is precluded.ReferencesSlavin ML. Brow droop after superficial temporal artery biopsy. Arch Ophthalmol 1986. 1041127.Dummer W, Zillikens D, Schulz A. et al. Scalp necrosis in temporal (giant cell) arteritis:implications for the dermatologic surgeon. Clin Exp Dermatol 1996. 21154–158.158.Haist SA. Stroke after temporal artery biopsy. Mayo Clin Proc 1985. 6053.Disclosure of InterestNone declared

Background: The use of three-dimensional printing (3D) application technology continues to shine in oral and maxillofacial surgery. Current applications of in maxillofacial surgery include trauma surgery, pathology induced defects, tissue engineering, complex temporomandibular joint reconstruction and correction of complicated facial asymmetry. Objective: The aims of this study were to review the current methods of 3D printing in the literature and explore their application in oral and maxillofacial surgery. Methods: A PubMed search was performed to review current methods of 3D printing within surgery and to look at their merits and pitfalls. Their use within facial surgery was then noted. Findings: We found there were three types of technology mainly used in surgical 3D printing. The main use within facial surgery included 3D reconstruction planning, custom implants and novel tissue engineering. Conclusion: 3D printing technology in surgery has advanced greatly since its infancy in 1994. Its use within maxillofacial surgery continues to show growth and exciting prospect.