SARS-CoV-2 Infection
Conditions
Keywords
lung thrombosis, pulmonary embolism, lung scintigraphy, alveolar albumin uptake
Brief summary
Investigators aimed to better understand the pathophysiology of SARS-CoV-2 pneumonia in non-critically ill hospitalized patients secondarily presenting with clinical deterioration and increase in oxygen requirement
Detailed description
Investigators plan to consecutively enrol 25 patients without clinical or biological evidence for superinfection, without left ventricular dysfunction and for whom a pulmonary embolism was discarded by computed tomography pulmonary angiography. Investigators will investigate lung ventilation and perfusion (LVP) by LVP scintigraphy, and, 24 hours later, left and right ventricular function by 99mTc-labelled albumin gated-blood-pool scintigraphy with late (60 mn) tomographic albumin images on the lungs to evaluate lung albumin retention that could indicate microvascular injuries with secondary edema
Interventions
DIAGNOSTIC_TESTlung ventilation/perfusion scintigraphy
Chest CT-scan will be performed with blocked inspiration. Lung ventilation/perfusion scintigraphy imaging will be performed within 24hrs after CT pulmonary angiography, 410MBq of Technegas will be inhaled by patients and ventilation tomography performed thereafter. Then, 185MBq 99mTc-macroaggegates will be injected intravenously followed by the perfusion tomography. A combined CT acquisition will be performed. The day following lung ventilation/perfusion scintigraphy, 740MBq of Tc99m labeled albumin will be intravenously administered. Cardiac gated-blood-pool scintigraphy will be then performed in best septal left anterior oblique and left profile according to specific parameters. 45-60 min after injection, a non-gated tomographic acquisition over the lungs will be done, with the same parameters than for PS SPECT, resulting in a late albumin acquisition.
Sponsors
Centre Hospitalier Princesse Grace
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Non-critically ill patients hospitalized in the COVID-19 Unit of the Centre Hospitalier Princesse Grace of Monaco * Presenting with a sudden clinical deterioration defined by a respiratory rate impairment and/or a rise of oxygen flow to reach a peripheral capillary oxygen saturation (SpO2) of more than 95% during at least 48 hours * a diagnosis of pulmonary embolism was discarded by CT pulmonary angiography * no clinical or biological (procalcitonin levels) evidence of lung superinfection * without clinical evidence for LV dysfunction
Exclusion criteria
* Non confirmed COVID-19 pneumonia according to the WHO guidance by a positive result of RT-PCR assay of nasal and pharyngeal swabs, * Patients without peripheral pulmonary ground-glass opacities or air-space consolidation on their chest CT scan at admission and common laboratory findings including lymphocytopenia, eosinopenia, significantly elevated markers of organ inflammation such as fibrinogen and C-reactive protein. * Patients could not be included if their medical condition was unstable or precluded a safe transfer to the nuclear medicine department, if they were under mechanical ventilation (either non-invasive or invasive), if they required critical care unit, or in case of a pregnancy.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Scintigraphic pattern of peripheral lung thrombosis | During hospitalization | Determination of the number of patients/pulmonary segments with scintigraphic pattern of peripheral lung thrombosis on the basis of a mismatch between normal ventilation and abnormal perfusion |
| Pulmonary microvascular injury | During hospitalization | Determination of the number of patients/pulmonary segments with evidence for microvascular injury on the basis of a lung 99mTc albumin retention, calculated as albumin uptake normalized by the macro-aggregates perfusion uptake |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Prognosis evolution at 15 days | 15 days after hospitalization | Determination of prognosis using categorical variables: worsening or stability vs improvement in the 15 following days, delay to the recovery of a 95% or more SpO2 in ambient air below vs above 15 days, hospitalization duration below vs above 15 days |
| CT abnormalities prognostic value | 15 days after hospitalization | The prognostic value of the extent of CT abnormalities, a right ventricular ejection fraction below vs above 50%, a significant albumin uptake (AI/PI) above or equal to 1.7, and the presence and/or number of paradoxically hypoventilated and hypoperfused normal segments will be evaluated by Fisher's exact test and Mann Whitney U test |
Countries
Monaco
Outcome results
None listed