In a world-first study, neonatologist Martin Kluckow hopes to dramatically reduce damage to the heart and lungs in preterm infants. 

Despite improved survival rates, some of the smallest babies face a significant chance of disability. Based at the Newborn Care Centre at Royal North Shore Hospital, the study (funded by the Foundation since 1997) is looking at heart function in these fragile infants. Researchers are collaborating with Royal Prince Alfred Hospital (Sydney) and King Edward Memorial Hospital (Perth).

Ducts in premature babies

The ductus arteriosus (or ‘duct') is a normal structure that connects the main body artery to the main lung artery. It is necessary for the fetus, but should close soon after birth.

In babies born at the right time the duct closes within 1–2 days of birth. In very premature babies, the duct often remains open for some time after birth.

This condition is known as patent ductus arteriosus (PDA). It can cause lung damage and bleeding, the need for later surgery to close the duct, or even disability.

Our researchers aim to identify the best way to manage the duct in premature babies to reduce these complications.

Damage to the lungs and brain

If the duct doesn't close soon after birth and remains large, it can cause
excess blood to flow to the lungs, which in turn causes lung damage. The diversion of blood from essential structures can also cause brain injury and sometimes bleeding into the brain. The result can be long-term disability.

Different treatment methods

There is currently a range of approaches:

• If the duct is large, a small number of doctors act early, using a medication called indomethacin to close it.
• Most doctors wait until the open duct causes symptoms (often by day 3–4 of life), before treating it.

In other cases, no treatment is given.

Lack of data

The first two approaches are used in nurseries around the world. But the choice is not based on any current data, and there is no evidence of either being a better or worse option.

Research aims

The research team hopes to learn whether it is better to assist closure of a large duct early with indomethacin, wait until it presents with symptoms, or let the duct close naturally.

What happens in this study?

The study will enrol 350 very premature babies from several major hospitals in Australia. All babies born more than 10 weeks early are eligible. Doctors use a harmless ultrasound of the heart to see if the duct is closing by itself, or is large and open.

Babies who have a small duct will receive standard care, and no treatment for the duct. Babies who have a large duct will be chosen randomly (by chance) to receive either early treatment with indomethacin, or a placebo (sterile water).

Further ultrasounds will record what happens to the duct. Any side effects attributable to the duct or the indomethacin will be recorded.

Open treatment (without the use of random placebos) will be allowed if a baby's doctor feels the duct needs treating during the period of the trial.

Benefits of this research

The study will increase understanding of heart function in this vulnerable group of infants, and determine the best treatments and therapies for each situation. Information from the longitudinal studies is being used by researchers and clinicians around the world to reduce harm and suffering in preterm babies.

Already, most neonatal intensive care units around Australia have adopted the use of point-of-care ultrasound, to assess cardiac function. There is also growing interest in and use of the study's techniques internationally.

The team has also developed a national training and accreditation process, for trainee neonatologists interested in this research.