Aim: Use of contrast enhanced ultrasound (CEUS) in severe cases of COVID-19 infection to assess pulmonary changes near the pleura.
Material and methods: Bedside examinations by an experienced intensive care unit examiner using a multi-frequency probe (C1-6 MHz) with B-mode and CEUS to assess pleural-near changes in severe cases of COVID-19 infection with respiratory failure. CEUS with bolus delivery via a central venous catheter of 2.4 ml Sulphur hexafluoride microbubbles from the arterial phase (10-15 s) to the late phase of 5 min. Digital storage of cine sequences of the lung sound with abdomen for independent assessment with the subsequently performed contrast-enhanced dual-source CT.
Results: In 11 intubated and ventilated patients (arithmetic mean 62 years, 48 to 78 years, 3 women) with confirmed severe COVID-19 infections, a peripherally accentuated consolidation with irregular hyperemia was found in the CEUS and also in the CT examination. Of the 5 cases with pulmonary arterial embolisms, signs of right ventricular failure were found. In all cases, using CEUS low perfused areas of the pleura with adjacent hyperemia could be detected, while, with CT segmental contrast medium, gaps with subpleural compressions were found. Interstitial changes near the pleura led to B-lines and to ground glass opacities in the CT. Near the diaphragm a delayed arterial contrast of the liver was observed. In addition, in 2 cases partial atelectasis, in 3 cases marginal pleural effusions were found.
Conclusion: CEUS opens up new possibilities for bedside monitoring of pleural reactive inflammatory or peripheral thrombus embolism in severe cases of COVID-19 infection.
Keywords: COVID-19 infection; lung- Contrast-enhanced ultrasound (CEUS); peripheral embolic consolidation; pleural affection.