CASE 1

A 61-year-old woman patient (PADUA index: 4, Caprini index: 5) experienced 7 days of respiratory distress. She was confirmed COVID-19 positive thanks to a real-time reverse transcription polymerase chain reaction (rRT-PCR) test. After admission, high flow nasal cannula (HFNC) and supportive care were performed immediately. At day 4, she complained of fatigue of the right lower limb. Due to the low oxygen saturation, a cranial computerized tomography (CT) scan was not performed immediately. At day 6, a bedside chest X-ray was performed, as shown in Fig. 1A . At day 8, there was obvious edema of the right lower extremity. Consequently, the patient was scheduled for color ultrasound (US) detection to screen for deep venous thrombosis (DVT). The scan confirmed that there was fresh thrombosis in the right femoral vein. She was anticoagulated with enoxaparin sodium (4000U, q12 h). At day 10, the patient became drowsy and had evidence of right limb hemiplegia. A cerebral haemorrhage may have been the reason for these symptoms, a leading cause of morbidity in COVID-19 patients 6. Anticoagulation was consequently withheld indefinitely and recommended implantation of an IVCF to prevent fatal PE occurrence. A CT scan of the chest at Day 10 had showed typical COVID-19 features in the lungs (Fig. 1B ). She was transported to the digital subtraction angiograph (DSA) operation room for IVCF implantation. After a successful Seldinger puncture of the left femoral vein, a permanent VenaTech® LP IVC filter (B. Braun, Melsungen, Germany) was placed underneath the right renal vein, as shown in Figs. 1C-1D . Antibiotic and supportive therapies were also optimised. A repeat chest X-ray on day 13 (Fig. 1E ) had showed signs of improvement compared to day 6. She was followed up regularly with her blood work (Table 1 ). C-reactive protein (CRP), neutrophil count, D-dimer, and high-sensitivity Troponin I (hsTNI) levels were all on the rise. The lymphocyte count was however improving. This together with hsTNI normalised at day 21. CT scan of the chest at day 23 (Fig. 1F ).
She was eventually asymptomatic and discharged at day 28. This patient was the first case to receive DSA-guided IVCF implantation in our COVID-19 therapy centre. The DSA operation room and equipment was meticulously disinfected to safeguard the health of patients making use of the service in the future.