Experience from a Singapore tertiary hospital with restructuring of a vascular surgery practice in response to national and institutional policies during the COVID-19 pandemic.

Singapore was one of the first countries to be affected by COVID-19, with the index patient diagnosed on January 23, 2020. For 2 weeks in February, we had the highest number of COVID-19 cases behind China. In this article, we summarize the key national and institutional policies that were implemented in response to COVID-19. We also describe in detail, with relevant data, how our vascular surgery practice has changed because of these policies and COVID-19. We show that with a segregated team model, the vascular surgery unit can still function while reducing risk of cross-contamination. We explain the various strategies adopted to reduce outpatient and inpatient volume. We provide a detailed breakdown of the type of vascular surgical cases that were performed during the COVID-19 pandemic and compare it with preceding months. We discuss our operating room and personal protective equipment protocols in managing a COVID-19 patient and share how we continue surgical training amid the pandemic. We also discuss the challenges we might face in the future as COVID-19 regresses.

Assessment of Flow after Lower Extremity Endovascular Revascularisation: A Feasibility Study Using Time Attenuation Curve Analysis of Digital Subtraction Angiography.

OBJECTIVES: Endovascular revascularisation is the mainstay of the treatment of lower extremity peripheral arterial disease. Improvement in perfusion after treatment is often quantified by a corresponding increment in ankle or toe brachial indices. These measurements are difficult to obtain in patients with foot wounds, and have to be performed at a separate time and setting after revascularisation. This preliminary study aimed to evaluate the use of parametric colour coding and analysis of time attenuation curves as a real time quantitative measure of perfusion after endovascular revascularisation. METHODS: Forty-seven consecutive patients with critical limb ischaemia were retrospectively enrolled and analysed. Parametric colour coding and generation of time attenuation curves in the main pedal vessel was performed for pre- and post-intervention digital subtraction angiograms of each patient. The change in time attenuation curve parameters was compared with the change in ankle or toe brachial indices before and after intervention. RESULTS: Comparing before and after lower extremity endovascular intervention, there were significant changes in the washout parameters derived from the time attenuation curve. The percentage of contrast decay 4 seconds after peak (I 4s) demonstrated the strongest correlation (R = .482) with the change in ankle or toe brachial indices. CONCLUSIONS: Parametric colour coding and time attenuation curve analysis might be a helpful tool that can provide real time intra-procedural quantitative data on pedal perfusion which can improve clinical outcomes.

Successful Endovascular Management of a Case of Aorto-oesophageal Fistula Presenting as Life Threatening Upper Gastrointestinal Bleed.

INTRODUCTION: Aorto-oesophageal fistula is a rare but life threatening cause of upper gastrointestinal haemorrhage. Severity of presentation and complexity of subsequent management depends on the size of the defect on both the aortic side and oesophagus. REPORT: The patient was a 67 year old Chinese man, who presented initially with a Stanford type A dissection with caudal extension to the right common iliac artery. The patient underwent replacement of the ascending aorta and proximal arch with debranching of the right innominate artery and aortic valve replacement. A follow up computed tomography (CT) aortogram done in the post-operative period showed a stable appearance of the caudal extension of the aortic dissection. The patient was discharged with a plan for future stenting of the thoracic aorta. Three weeks later the patient re-presented with an upper gastrointestinal bleed from an aorto-oesophageal fistula. The patient underwent endovascular stenting of the descending aorta for management of the fistula. Repeat oesophagogastroduodenoscopy showed a small erosion 35 cm from the incisors where the previous bleeding site had been. No further bleeding was seen. DISCUSSION: The patient recovered uneventfully after the procedure. Follow up CT aortogram done at 6 weeks demonstrated thrombosis of the false lumen of the descending thoracic aorta. Aorto-oesophageal fistula related to chronic type B aortic dissection is an extremely rare clinical entity and presents a challenge to the treating surgeon. This case demonstrates that selected cases can be judiciously managed by thoracic endovascular aneurysm repair alone.