Table 1 Eligibility criteria for participants
Inclusion criteria | Exclusion criteria |
|---|---|
Confirmed or suspected COVID-19 If ‘suspected’, results must be pending or testing intended | Enrolled in another clinical trial that is unapproved for co-enrolment |
Ability to obtain informed consent/assent to participate in study | Heparin allergy or heparin-induced thrombocytopenia |
Age 18 years or older | APTT > 100 s |
Requiring high-flow nasal oxygen (>30l/min) or positive pressure ventilator support or invasive mechanical ventilation in the ICU for a time period of no greater than 48 h | Pulmonary bleeding, which is frank bleeding in the trachea, bronchi or lungs with repeated haemoptysis or requiring repeated suctioning |
D-dimers > 200 ng/ml | Platelet count < 50 × 109 per l |
Acute opacities on chest imaging affecting at least one lung quadrant. ‘Acute opacities’ do not include effusions, lobar/lung collapse or nodules | Uncontrolled bleeding |
Currently in a higher level of care area designated for inpatient care of patients where therapies including non-positive pressure ventilatory support (e.g. high-flow nasal oxygen) can be provided | Pregnant or suspected pregnancy (urine or serum HCG will be recorded) |
Receiving or about to commence ECMO or HFOV | |
Myopathy, spinal cord injury or nerve injury or disease with a likely prolonged incapacity to breathe independently, e.g. Guillain-Barre syndrome | |
Usually receives home oxygen | |
Fully dependent on others for personal care due to physical or cognitive decline prior to this illness (premorbid status) | |
Death is imminent or inevitable within 24 h | |
The clinical team would not be able to set up the study nebuliser and ventilator circuit as required including with active humidification | |
Clinician objection | |
The use or anticipated use of nebulised tobramycin during this clinical episode | |
Any other specific contraindication to anticoagulation including prophylactic anticoagulation not otherwise listed here | |
Relapse in clinical condition requiring advances respiratory support in patient that had fully weaned from advanced respiratory support | |
Receiving any direct/novel oral anticoagulant |