What is the Preferred Screening Tool for COVID-19 in Asymptomatic Patients Undergoing a Surgical or Diagnostic Procedure?

INTRODUCTION: Since the outbreak of COVID-19, measures were taken to protect healthcare staff from infection, to prevent infection of patients admitted to the hospital and to distribute PPE according to need. To assure the proper protection without overuse of limited supply of these equipments, screening of patients before surgical or diagnostic procedure was implemented. This study evaluates the results of this screening. METHOD: All patients screened for COVID-19 before procedure warranting either general, locoregional anaesthesia or sedation were included. Screening included a symptom questionnaire by phone, PCR and HRCT chest testing. Surgical or procedural details were registered together with actions taken based on screening results. RESULTS: Three hundred ninety-eight screenings were performed on 386 patients. The symptom questionnaire was completed in 72% of screenings. In 371 screenings, PCR testing was performed and negative. HRCT chest found 18 cases where COVID-19 could not be excluded, with negative PCR testing. Three patients had their surgery postponed due to inconclusive screening, and additional measures were taken in three other patients. There were incidental findings in 14% of HRCT chest scans. DISCUSSION: Pre-operative screening will differentiate if PPE is needed for procedures and which patients can safely have elective surgery during this COVID-19 pandemic and in the times to come. HRCT chest has no additional value in the pre-operative screening of asymptomatic patients. Screening can be performed with a symptom questionnaire, and additional screening with PCR testing in high-risk patient groups should be considered.

The Hemashield Woven prosthesis in the thoracic aorta: a prospective computer tomography follow-up study.

BACKGROUND: Dacron prostheses in humans have been documented to present long-term fiber alterations, that may account for late graft dilatation. Late dilatation has been documented mainly in knitted prostheses, implanted in the abdominal and thoracic aorta. Dilatation of the collagen-impregnated Hemashield Woven prosthesis has not been studied prospectively in the thoracic aorta. METHODS: Twenty patients were prospectively included. The intraoperative performance of the graft and mid-term clinical behaviour were studied. The graft distensibility was evaluated by postoperative, 1 and 3 yr computed tomographic diameter follow-up. RESULTS: There were no hospital deaths. Two graft-unrelated deaths occurred at 3 yr. The graft performance was excellent or good for most aspects. No significant changes in CT diameter occurred throughout the 3 yr follow-up. CONCLUSION: The collagen-impregnated Hemashield Woven prosthesis is considered safe in replacements of the thoracic aorta. Future evaluation should focus on the very long-term behaviour in young adults.

Gelseal versus Gelweave dacron prosthetic grafts in the descending thoracic aorta: a two-year computed tomography scan follow-up study.

BACKGROUND: In the abdominal aorta, the use of knitted rather than woven dacron prostheses has shown an early and slow late dilation. The dilation of woven versus knitted dacron prostheses in the thoracic aortic position has not yet been investigated. METHOD: From 1992, 25 patients entered a prospective study: 13 Gelweave and 12 Gelseal prostheses (diameter 18-26 mm) were implanted in the descending thoracic aorta. Computed tomography (CT) scans without contrast-enhancement were performed 2 weeks, and 1 and 2 years postoperatively. The full length of the grafts was scanned and the diameter was measured in mm measured at a level outside the areas of intercostal artery reimplantation. Patient determinants analysed were age, hypertension and implantation diameter of the grafts. The Gelseal group had a mean age of 63.7 years and seven were males. The Gelweave group had a mean age of 67.8 years and seven were males. RESULTS: the mean implantation diameters were 19.6 +/- 1.7 mm and 22.0 +/- 2.7 mm (P = 0.02) for the Gelseal and Gelweave grafts, respectively. On the CT-scans at 2 weeks postoperatively, the diameter had increased by 18.8 +/- 4.8% (P = 0.0001) in the Gelseal and by 5.7 +/- 6.4% (P = 0.007) in the Gelweave grafts. This difference in diameter at 2 weeks between the two prostheses was significant (P < 0.0000 1). At 1 year the diameter had increased by 28.4 +/- 5.2% (P = 0.0001) and by 8.4 +/- 4.6% (P = 0.0003) for the Gelseal and Gelweave grafts, respectively, compared with the implantation diameter. The increase in diameter between the postoperative values at 2 weeks and those at 1 year was statistically significant in the Gelseal grafts (P = 0.0002) but not in the Gelweave grafts (P = 0.56). At 2 years an increase in diameter by 31.4 +/- 5.2% (P = 0.0001) and by 7.4 +/- 7.1% (P = 0.014) for the knitted and woven prosthetic grafts, respectively, was noted compared with the initial implantation diameter. The increase in diameter between the CT measurements at 2 weeks and those at 2 years was statistically significant in the Gelseal group (P = 0.001) but not in the Gelweave group (P = 0.86). The difference in this late increase in diameter between the two implanted grafts was also significant (P < 0.005). Age, hypertension and initial diameter did not appear to be significant determinants. CONCLUSION: In contrast to the Gelseal prosthesis in the descending aorta, the Gelweave prosthesis does not show any late dilation.