Study outcomes
| Primary feasibility outcomes | Proportion of eligible patients approached for consent |
| Proportion of participants receiving their first protein supplementation within 72 hours of enrolment | |
| Participant accrual, defined as an average monthly enrolment of at least one participant per centre | |
| Protocol adherence, defined as >80% of protein target administered according to the protocol in the intervention arm | |
| Secondary clinical outcomes | PICU mortality |
| PICU LOS 28-day PICU-free days | |
| Hospital LOS | |
| MV duration 28-day ventilator-free days | |
| Development of AEs including feeding intolerance, diarrhoea, GI bleeding, and treatment used for GI bleeding | |
| Change in muscle size (eg, ultrasound guided cross-sectional area of the rectus femoris, diaphragm thickness) during PICU stay, at PICU discharge, hospital discharge and 6 months later | |
| Change in anthropometric measurements (height, weight, BMI) at PICU discharge, hospital discharge and 6 months later | |
| Change in functional status (PEDI-CAT score, FSS score, hand-grip strength and 6-minute walk test) at hospital discharge and 6 months later |
AE, adverse effects; BMI, body mass index; FSS, Functional Status Score; GI, gastrointestinal; LOS, length of stay; MV, mechanical ventilation; PEDI-CAT, Paediatric Evaluation of Disability Inventory—Computer Adaptive Test; PICU, paediatric intensive care unit.