BASE

Metabolic acidosis is a build-up of acid in the blood. In the UK, 8,000 infants are born very preterm each year and some will develop metabolic acidosis during their stay on a neonatal unit.

Sodium bicarbonate is often used when a premature baby has metabolic acidosis. Some doctors believe that giving sodium bicarbonate lowers acid levels in the blood and helps the working of the heart, but others believe it can raise acid levels in the cells of the body which can affect blood flow to the brain and other organs. At the moment we do not know which approach is best for babies.

What are the BASE Studies?

The BASE Studies will help us learn more about metabolic acidosis in very preterm babies, including how it is currently treated, the use of sodium bicarbonate and how treatment affects babies' health. We also want to understand if we can successfully carry out a future trial in this area.

BASE Trial & Feasibility Study is investigating whether sodium bicarbonate should be used to treat metabolic acidosis in very premature babies. Premature babies who develop metabolic acidosis will be randomly allocated to one of two groups:

• Will be given sodium bicarbonate when they have metabolic acidosis
• Will not be given sodium bicarbonate when they have metabolic acidosis

The feasibility study will also look at whether it is possible to run a larger study of this treatment in the future. It will look at whether doctors and nurses can collect the information needed and provide care according to the study plan, as well as whether enough babies can be recruited to make a larger study possible.

BASE Observational Study will help us understand how often metabolic acidosis occurs in very preterm babies, how it is treated in routine clinical practice and whether there is any association between treatment and health outcomes.

Qualitative QuinteT Study aims to explore the views of parents, healthcare professionals and study staff. We want to understand how metabolic acidosis is currently managed in neonatal units across the UK, It will help us understand how metabolic acidosis is currently managed in neonatal units across the UK, parents' experiences of being invited to take part in the BASE Trial, and how future research in this area could be improved.

The BASE Studies are coordinated by the National Perinatal Epidemiology Unit Clinical Trial Unit (NPEU CTU) at the University of Oxford and is funded by the National Institute of National Institute for Health and Care Research (NIHR) Health Technology Assessment (HTA) programme.

For more information, please contact the BASE team at base@npeu.ox.ac.uk