After checking S7, S6 and S5 lesions vascular supply, the hypertrophic right inferior phrenic artery was selectively catheterized, and LUF 2 mg emulsified with EPI 5 mg was injected (Figures 1a,1b). TACE procedure was immediately interrupted due to appearance of not previously described pulmonary shunts (Figure 1c). 

Thereafter, HCCs were treated with standard doses of LUF and EPI through the right hepatic artery. No adverse events related to TACE were recorded, during and immediately after the procedure. Twenty hours later, the patient presented with fever (38.0°C) and desaturation (SatO2 78%), in absence of pronounced dyspnea. Arterial blood gas analysis showed respiratory failure with pH 7.40, pO2 34, pCO2 49, SpO2 65%, lactates 1.2, P/F 161. Differential diagnosis was made. Acute Respiratory Failure should prompt a rapid evaluation and physicians are required to quickly rule out the most common acute pulmonary pathologies. Acquired infectious pneumonia is quite a common cause of rapid deteriorating respiratory function and acute respiratory distress syndrome. Among infectious pneumonia, due to current high incidence scenario with rapidly spreading intra-hospital potential outbreaks, COVID-19 should be the first pathology to be excluded in order to keep infected patients out of SARS-CoV-2 free departments and, on the other hand, to prevent SARS-CoV-2 negative patients to become ill. Although our patient had been tested for COVID-19 before hospital admission, high rates of false negative RT-PCR tests should suggest to keep a low threshold for re-testing, especially if we take into consideration our subject’s clinical presentation with fever, acute respiratory failure and the absence of frank dyspnea which are all clinical characteristics of acute SARS-CoV-2 infection.Also, in this specific case, pulmonary venous thromboembolism should be suspected given the sudden desaturation and considering the hypercoagulable state due to active cancer, the post-procedural bed confinement and the recent vascular maneuvers. 

Furthermore, the accidental injection of LUF + EPI into not previously known pulmonary shunt should raise the suspicion of possible adverse events related to the injection of relatively high doses of iodinated contrast agents into pulmonary parenchyma thus provoking chemical pneumonia. Oxygen support was then delivered (VM 50% 12 l/min), with benefit. Blood tests were repeated and they revealed unchanged white blood cells count (3,780/mm3), with relatively low lymphocytes (10%); hemoglobin, C-Reactive Protein, D-Dimer and ferritin were normal. 

Chest X-ray showed an interstitial lung reinforcement and a possible basal right pneumonia. Due to parallel high incidence clinical scenario and the radiologic findings, a third SARS-CoV-2 nasopharyngeal swab was obtained, which still tested negative. To rule out the other possible complications, the patient underwent chest CT-scan which revealed the presence of radio-opaque material within the apical and posterior segment of the lower right lobe, that was suggestive for lipiodol accumulation (Figures 2a,2b). Liver accumulation were as well noted (Figure 2c). Right basal pneumonia was not confirmed, despite the presence of mild pleural effusion and lobar dystelectasia. Both antibiotics and low-molecular-weight heparin prophylaxis were started, and patient’s respiratory function was closely monitored. The patient experienced a progressive improvement in respiratory function with oxygen weaning after 7 days, and was discharged without sequelae.