Pilot Optimizing Transfusion Thresholds in Critically-ill Children With Anaemia (P-OpTTICCA): a Pilot Trial for a Large Pragmatic International Parallel Open-label Non-inferiority Randomised Controlled Trial.

Patients in paediatric intensive care units (PICU) are among the main groups of transfusion recipients. Blood transfusions expose recipients to infectious and non-infectious serious hazards. Despite an increasing number of red blood cell (RBC) transfusion threshold randomised controlled trials (RCT) to date, only one large RCT, the Transfusion Requirement In PICU (TRIPICU) study (Lacroix. N Engl J Med 2007;356:1609-19) informs practice in PICU. This dearth of paediatric data was reiterated by a recent National Heart, Lung and Blood Institutes state of the art symposium. Despite being internally robust, the generalizability of TRIPICU has been questioned given that nearly 90% of critically ill children with haemoglobin (Hb) level ≤ 95 g/L were not enrolled for a range of pre-specified reasons including severity of illness, clinical instability and uncertain physician buy-in, thus threatening broader application of this critical knowledge into practice. Recent data and evidence summarised in systematic reviews support the need to explore the benefits and safety of Hb threshold ≤ 70 g/L for almost all critically ill children, not only those who would have been enrolled in TRIPICU.

We propose an international pilot study that will inform the design of a large pragmatic non-inferiority RCT (termed OpTTICCA) conceived to derive generalizable transfusion guidance for physicians.

Objectives of the pilot-RCT. Specific aims are to:

1. Establish the feasibility of enrolling ≥80% of eligible patients.
2. Document adherence to study intervention ≥80% (restrictive transfusion policy).
3. Assess the incidence rate of the primary outcome measure of the full RCT (new and progressive multiple organ dysfunction syndrome, which includes mortality).
4. Establish the feasibility of using routinely collected clinical information from electronic medical data monitoring system (eMDMS) to enhance cost-efficiency.

In the pilot-RCT, we will enrol 120 patients (20 to 40/site) in PICUs equipped with electronic medical data monitoring system (eMDMS). This trial builds on successful prior RCTs that involved international collaboration and funding (Canada, United Kingdom, France): TRIPICU, Age of Blood Evaluation (ABLE) (Lacroix. N Engl J Med 2015) and Age of Blood in Children in PICU (ABC-PICU study: Tucci et al. Trials 2018). The pilot-RCT will be considered as the vanguard phase of the full OpTTICCA RCT if no important design changes are required.