Comparison of carbon dioxide control during pressure controlled versus pressure regulated volume controlled ventilation in children (CoCO2): protocol for a pilot digital randomized controlled trial
Authors: Mozun Rebeca , Chopard Daphné , Zapf Florian , Baumann Philipp , Brotschi Barbara , Adam Anika , Jaeggi Vera , Bangerter Beat , Gibbons Kristen , Burren Juerg , Schlapbach Luregn J 
Published: March 2024

ABSTRACTIntroductionDigital trials are a promising strategy to increase the evidence base for common interventions and may convey considerable efficiency benefits in trial conduct. Although paediatric intensive care units (PICUs) are rich in routine electronic data, highly pragmatic digital trials in this field remain scarce. There are unmet evidence needs for optimal mechanical ventilation modes in paediatric intensive care. We aim to test the feasibility of a digital PICU trial comparing two modes of invasive mechanical ventilation using carbon dioxide (CO2) control as the outcome measure.Methods and analysisSingle-centre, open-labelled, randomized controlled pilot trial with two parallel treatment arms comparing pressure control (PC) vs pressure-regulated volume control (PRVC). Patients are eligible if aged <18 years, weighing >2 kg, have an arterial line, and require >60 minutes of mechanical ventilation during PICU hospitalization at the University Children’s Hospital Zurich. Exclusion criteria include cardiac shunt lesions, pulmonary hypertension under treatment, and intracranial hypertension. CO2is measured using three methods: end-tidal (continuous), transcutaneous (continuous), and blood gas analyses (intermittent). Baseline, intervention, and outcome data are collected electronically from the patients’ routine electronic health records. The primary feasibility outcome is adherence to the assigned ventilation mode, while the primary physiological outcome is the proportion of time spent within the target range of CO2(end-tidal, normocarbia defined as CO2≥ 4.5, ≤ 6 kPa). Both outcomes are captured digitally every minute from randomization until censoring (48 hours after randomization, extubation, discharge, or death, whichever comes first). Analysis will occur on an intention-to-treat basis. We aim to enrol 60 patients in total. Recruitment started in January 2024 and is planned to continue for 6 months.Ethics and disseminationThis study received ethical approval (BASEC 2022-00829). Study results will be disseminated through publication in a peer-reviewed journal and other media like podcasts.Trial registration numberNCT058431ARTICLE SUMMARYThis study compares two commonly used modes of invasive mechanical ventilation in a randomized design. The trial will provide feasibility data to inform the conduct of digital trials by using electronic patient data directly extracted from the source systems, minimizing manual data collection and associated bias and thereby increasing local readiness for more efficient clinical trial conduct.Outcomes of this pilot trial relate to feasibility and physiological measures; future larger trials should also explore patient-centred outcomes.Blinding is not possible due to the nature of the intervention.Technical issues that may affect the availability or accuracy of data may arise and will be documented.Some aspects of digital trials, such as electronic informed consent, are not implemented in this trial.