Objective: This was a pilot study to determine the utility of daily lung ultrasound (LUS) in patients requiring veno-venous extracorporeal membrane oxygenation (VV-ECMO) for acute respiratory distress syndrome (ARDS). Design: This was a prospective, observational study. Setting: The study took place in the intensive care unit at Royal Papworth Hospital in Cambridge, UK. Participants: We recruited adult patients receiving VV-ECMO for ARDS. Interventions: All patients received a lung computed tomography (CT) scan and LUS on admission. Bedside chest radiography (CXR) and LUS were done on a daily basis until patients were decannulated. Measurements and main results: Daily LUS aeration scores were calculated according to the appearance of four defined patterns. An independent radiologist calculated corresponding scores for CT and CXR, retrospectively. These were checked for correlation with LUS aeration scores. There were statistically significant correlations between LUS versus CT ( r = 0.868, p = 0.002) and LUS versus CXR ( r = 0.498, p = 0.018) with good agreement and no evidence of proportional bias. LUS was able to detect 13.5% of pleural effusions and 54.2% of pneumothorax that were not picked up on CXR. In most of the patients who were weaned off VV-ECMO, a progressive reduction of LUS aeration scores corresponding to lung re-aeration was observed. Conclusions: LUS correlated with findings on CT and CXR for quantifying lung aeration and the clinical presentation of patients. LUS also picked up more pleural effusions and pneumothorax than CXR. Together with traditional imaging techniques, the routine use of LUS should be considered for this patient group.

Objectives Continuous positive airway pressure (CPAP) may be a useful treatment strategy for patients with severe COVID-19 pneumonia but its effectiveness in preventing mechanical ventilation is unknown. We aimed to evaluate the outcomes of COVID-19 patients treated with CPAP and determine predictors of CPAP response. Design This was a retrospective observational cohort study. Setting The study took place in the intensive care unit (ICU) at Royal Papworth Hospital (RPH) in Cambridge, UK. Patients We included all consecutive patients with confirmed COVID-19 pneumonia who were transferred from neighbouring hospitals between 14th March and 6th May, 2020 for consideration of ventilatory support. Intervention We instituted the use of CPAP for all patients who arrived in RPH not intubated and were not making satisfactory progress on supplemental oxygen alone. Measurements and main results Of 33 self-ventilating patients included in this study, 22 (66.7%) were male and the mean age was 54 ± 13.23 patients received CPAP. They were more hypoxaemic than those treated with oxygen alone (PaO2/FiO2 ratio; 84.3 ± 19.0 vs 170.0 ± 46.0 mmHg, p = 0.001). There was a significant improvement in PaO2/FiO2 ratio 1–2 hours after CPAP initiation (167.4 ± 49.0 from 84.3 ± 19.0 mmHg, p = 0.001). 14 (61%) patients responded to CPAP and 9 required intubation. There was no difference between these two groups in terms of the severity of baseline hypoxaemia (PaO2/FiO2 ratio; 84.5 ± 16.0 vs 83.9 ± 23.0 mmHg, p = 0.94) but CPAP responders had significantly lower C-reactive protein (CRP) (176 ± 83 vs 274 ± 63 mg/L, p = 0.007), interleukin-6 (IL-6) (30 ± 47 vs 139 ± 148 pg/mL, p = 0.037), and D-dimer (321 ± 267 vs 941 + 1990 ng/mL, p = 0.003). CT pulmonary angiogram was performed in 6 out of 9 intubated patients and demonstrated pulmonary emboli in 5 of them. All patients were discharged from ICU and there were no fatalities. Conclusions In this cohort, CPAP was an effective treatment modality to improve hypoxaemia and prevent invasive ventilation in a substantial proportion of patients with severe respiratory failure. Accepting the small sample size, we also found raised biomarkers of inflammation (CRP and IL-6) and coagulopathy (D-Dimer) to be more useful predictors of CPAP responsiveness than the severity of hypoxaemia, and could help to guide intubation decisions in this clinical setting.