RESUMEN
BACKGROUND: The incidence and outcome of pulmonary aspergillosis in coronavirus disease (COVID-19) patients on extracorporeal membrane oxygenation (ECMO) are unknown and have not been fully addressed. We investigated the incidence, risk factors and outcome of pulmonary aspergillosis in COVID-19 ECMO patients. In addition, the diagnostic utility of bronchoalveolar lavage fluid and CT scans in this setting were assessed. METHODS: We conducted a retrospective study on incidence and outcome of pulmonary aspergillosis in COVID-19 ECMO patients by reviewing clinical, radiological, and mycological evidence. These patients were admitted to a tertiary cardiothoracic centre during the early COVID-19 surge between March 2020 and January 2021. Results and measurements: The study included 88 predominantly male COVID-19 ECMO patients with a median age and a BMI of 48 years and 32 kg/m2, respectively. Pulmonary aspergillosis incidence was 10% and was associated with very high mortality. Patients with an Aspergillus infection were almost eight times more likely to die compared with those without infection in multivariate analysis (OR 7.81, 95% CI: 1.20-50.68). BALF GM correlated well with culture results, with a Kappa value of 0.8 (95% CI: 0.6, 1.0). However, serum galactomannan (GM) and serum (1-3)-ß-D-glucan (BDG) lacked sensitivity. Thoracic computed tomography (CT) diagnostic utility was also inconclusive, showing nonspecific ground glass opacities in almost all patients. CONCLUSIONS: In COVID-19 ECMO patients, pulmonary aspergillosis incidence was 10% and associated with very high mortality. Our results support the role of BALF in the diagnosis of pulmonary aspergillosis in COVID-19 ECMO patients. However, the diagnostic utility of BDG, serum GM, and CT scans is unclear.
RESUMEN
BACKGROUND: In a tertiary respiratory centre, large cohorts of patients are managed in an outpatient setting and require blood tests to monitor disease activity and organ toxicity. This requires either visits to tertiary centres for phlebotomy and physician review or utilisation of primary care services. OBJECTIVES: This study aims to validate remote capillary blood testing in an outpatient setting and analyse impact on clinical pathways. METHODS: A single-centre prospective cross-sectional validation and parallel observational study was performed. Remote finger prick capillary blood testing was validated compared with local standard venesection using comparative statistical analysis: paired t-test, correlation and Bland-Altman. Capillary was considered interchangeable with venous samples if all three criteria were met: non-significant paired t-test (ie, p>0.05), Pearson's correlation coefficient (r)>0.8% and 95% of tests within 10% difference through Bland-Altman (limits of agreement). In parallel, current clinical pathways including phlebotomy practice were analysed over 4 weeks to review test predictability. A subsequent pilot cohort study analysed potential impact of remote capillary blood sampling on shared decision making. A final implementation phase ensued to embed the service into clinical pathways within the institution. RESULTS: 117 paired capillary and venous blood samples were prospectively analysed. Interchangeability with venous blood was seen with glycated haemoglobin (%), total protein and C reactive protein. Further tests, although not interchangeable, are likely useful to enable longitudinal remote monitoring (eg, liver function and total IgE). 65% of outpatient clinic blood tests were predictable with 16% of patients requiring further follow-up. Patient and clinician-reported improvement in shared decision making given contemporaneous blood test results was observed. CONCLUSIONS: Remote capillary blood sampling can be used accurately for specific tests to monitor chronic disease, and when incorporated into an outpatient clinical pathway can improve shared decision making and patient experience. Further research is required to determine health economic impact and applicability within telemedicine-based outpatient care.