Key Messages:
There is no evidence for or against reducing fluids as a treatment option for patent ductus arteriosus in premature babies.
We need randomized controlled trials that answer our question to help inform clinical decisions.
What is patent ductus arteriosus (PDA)?
The ductus arteriosus is an extra blood vessel that runs between the heart and lungs in babies before birth and just after. In order for the heart and lungs to work properly after birth, this blood vessel must close. In most babies, it closes naturally in a few days, and they are fine.
However, in some premature babies (babies born before 37 weeks of pregnancy), the ductus arteriosus stays open (which is called patent). This means extra blood may flow into the lungs and cause problems (symptomatic). This condition is called patent ductus arteriosus (PDA).
PDA may be treated by reducing the amount of fluids given to these babies. We are not sure of the benefits and risks of giving a premature baby less fluid to reduce the problems associated with PDA.
What does restricting fluids mean?
Fluid restriction means limiting the amount of nutritional or medicinal fluids given to babies who are unable to breastfeed or bottle-feed. When babies are unable to take anything by mouth, their nutrition and medicine are given either through their veins (parenteral nutrition) or through a tube into their stomach (enteral nutrition). Limiting the amount of this fluid is one treatment used for babies with PDA.
Experts believe that limiting liquids may help by potentially changing how the heart pumps blood around the body, and by reducing the effort needed for the heart to pump blood. However, it may also be risky to restrict liquid intake. One risk is that the baby may not get enough nutrition.
What did we want to find out?
We wanted to find out if restricting fluids helped to reduce sickness or death in babies with PDA.
We wanted to find evidence that would help doctors decide whether to restrict fluid feeding or not, but we did not find any studies.
What did we do?
We searched for studies that assessed reducing fluid feeding, either by a tube into the stomach, or by a needle into a vein, in babies with PDA.
What did we find?
We did not find any randomized control trials (a trial in which participants are assigned to different study groups by chance) that assessed this treatment in premature babies with PDA.
What are the limitations of the evidence?
We did not find any evidence from randomized control trials.
How up to date is this evidence?
The evidence is up-to-date until October 2023.
No evidence from RCTs is currently available to evaluate the benefits and harms of fluid restriction for the treatment of symptomatic patent ductus arteriosus in preterm infants. We identified no ongoing studies.
Evidence from sufficiently powered RCTs evaluating fluid restriction for treatment of symptomatic PDA in preterm neonates is needed to inform clinical decisions.
The ductus arteriosus is a blood vessel connecting the main pulmonary artery and the proximal descending aorta. After birth, the ductus arteriosus usually closes completely. However, sometimes it remains patent in the neonate, which is called patent ductus arteriosus (PDA). If a PDA is clinically symptomatic, it can lead to overcirculation in the lungs, and reduced perfusion to the gut and kidneys. Most clinical practice guidelines suggest fluid restriction as a conservative management strategy for the treatment of symptomatic PDA. Restricting fluid has been shown to reduce the incidence of PDA in older preterm infants. However, aggressive restriction of fluids may affect systemic blood flow in extremely preterm infants. Given the potential adverse effects, it is important to systematically evaluate the evidence on the use of fluid restriction to treat symptomatic PDA to inform clinical decisions.
To assess the effects of fluid restriction on morbidity and mortality for symptomatic PDA in preterm infants.
We searched CENTRAL, MEDLINE, and Embase in October 2023. We also searched Clinicaltrials.gov, ICTRP, ANZCTR, and Epistemonikos. We planned to search the reference list of included studies and relevant systematic reviews for studies not identified by the database searches, but did not identify any.
We planned to include randomized controlled trials (RCTs), quasi-RCTs, cluster-RCTs, and cross-over RCTs. We planned to include neonates who were born preterm (less than 37 weeks' gestational age), or with low birth weight (less than 2500 g), with a symptomatic PDA, diagnosed either clinically or by echocardiographic criteria, in the neonatal period. We planned to include studies that compared therapeutic restriction of parenteral or enteral fluids, or both, with or without diuretics, with control groups that received standard fluid intake, defined as no parenteral or enteral restriction, with or without diuretic use.
We used standard Cochrane methods. Our primary outcome was closure of PDA. Other relevant outcomes were all-cause mortality by 36 weeks' postmenstrual age, need for interventional closure of the PDA, need for treatment with a cyclooxygenase inhibitor, bronchopulmonary dysplasia, severe intraventricular hemorrhage, and duration of hospitalization. We planned to use GRADE to assess the certainty of evidence for each outcome.
We did not identify any completed or ongoing RCTs that met our inclusion criteria and explored the effectiveness and safety of fluid restriction to treat symptomatic PDA.