Research published in the American Journal of Respiratory and Critical Care Medicine has shown clinical observations, imaging tests and point-of-care blood tests are all important indicators of pulmonary angiopathy (blood vessel disease) in COVID-19 and could help determine disease severity.
Preliminary results released earlier in the year from the Trust’s critical care service established a clear link between Covid-19 and blood clotting, by using hi-tech CT scans to take images of lung function in patients most seriously affected by the disease. Results found that all of those tested suffered a lack of blood flow, suggesting clotting within the small vessels in the lung. The research paper Pulmonary Angiopathy in Severe COVID-19: Physiologic, Imaging and Hematologic Observations is available here.
The research examined 39 patients with Covid-19 induced respiratory failure, who were either mechanically ventilated or put on extracorporeal membrane oxygenation and had undergone CT pulmonary angiography, including where feasible, DECT (hi-tech imaging scans).
Key findings from the study:
- Clinical observations, point-of-care testing and imaging data showed an increased likelihood of hypercoagulability (the increased tendency for their blood to clot)
- A markedly impaired blood flow was observed in the lungs of 21 out of 33 patients, with CT scans indicating abnormally dilated blood vessels – likely caused by blood vessel disease and thrombosis
- Deep Vein Thrombosis (DVT) and acute pulmonary embolism was observed in 15 out of 39 patients CT scans and although DVT occurs commonly in critically ill patients, the research suggests that in Covid-19 patients there may be two causes at play - acute pulmonary embolism from DVT and widespread pulmonary angiopathy.
The paper concluded that these observations made through imaging, coupled with biological and haemotologoical features, point to major pulmonary vascular involvement in severe cases of COVID-19.
Dr Brij Patel, senior intensivist and clinical senior lecturer at Royal Brompton Hospital and Imperial College and lead author of the paper, said: “This multi-modal approach to describing Covid-19 in the intensive care unit maps our multi-disciplinary team approach to severe acute respiratory failure. Indeed, the lung physiology, imaging and blood tests all point to a spectrum of lung failure which significantly, involves damage to the blood vessels within the lung.
The question is if these manifestations are treatable traits allowing more targeted interventions to treat the damage to the blood vessels. Although this is only part of the complex picture of Covid-19 induced lung failure, we feel these observations are very important to enable others around the world really find a treatment for this devastating condition.”