When newborn babies are starved of oxygen it's vital to help them breathe to avoid brain damage, but sometimes the amount of oxygen they receive following resuscitation can harm the brain, so researchers are working to find out how much oxygen is too much.
A team from The Ritchie Centre at Hudson Institute of Medical Research and Monash University set out to find out how to control oxygen levels to maximise benefit and reduce harm; their findings have been published in the Journal of Cerebral Blood Flow & Metabolism.
Lead author, Dr Shiraz Badurdeen said oxygen is the most common drug given to newborn infants who are struggling to breathe, but current international guidelines give no guidance on what oxygen level is appropriate after a successful resuscitation.
"Each year, over 1,000 babies in Australia suffer from a critical shortage of oxygen at birth, resulting in a type of brain injury called hypoxic-ischaemic encephalopathy (HIE). Worldwide, HIE kills nearly a million babies each year. Oxygen is an important treatment during the resuscitation of these babies, but too much can be harmful." Dr Badurdeen said.
A simple change to newborn resuscitation
"Our latest research found that a simple change in how oxygen therapy is given can help protect the newborn's brain. By studying blood circulation and oxygen levels, we found that as little as 5 minutes of excessive oxygen exposure can damage the brain's mitochondria."
The issue arises because 100% oxygen is generally used during resuscitation, but until now there has been no clear evidence to say when the oxygen intake should be reduced and normal air (21% oxygen) introduced.
Co-researcher Dr Emily Camm, from Hudson Institute, said "Mitochondria are the cell's main energy producers, generating the fuel required to support a range of cellular functions, and when they are damaged, they can cause brain cells to die."
"Our team found that by quickly reducing oxygen therapy once the newborn's heartbeat has returned, mitochondrial function in the brain can be preserved."
"Our novel approach could protect babies from brain injury and reduce the risk of long-term cognitive disability which is commonly seen in survivors of HIE." Dr Camm said.
The findings will now be considered by international experts who make recommendations on newborn resuscitation, including joint lead author Professor Graeme Polglase.
"The study calls current practice into question, and I expect it to open up a new avenue of research to determine how best to safely administer oxygen to protect the vulnerable brain of newborns with HIE." Prof Polglase said.
About newborn resuscitation
Oxygen is crucial during the resuscitation of newborns to address hypoxia, a condition where insufficient oxygen reaches tissues. At birth, a newborn's transition from intrauterine to extrauterine life requires effective lung function to oxygenate blood and support vital organs.
In cases where a baby fails to establish adequate breathing or circulation, resuscitation with oxygen can prevent brain damage, organ failure, or death.
The resuscitation process typically includes positive pressure ventilation and continuous monitoring of oxygen saturation to ensure safe and effective oxygen delivery.
Excessive oxygen use can be harmful, leading to hyperoxia, which increases the risk of oxidative injury and long-term complications like retinopathy of prematurity (damage to the retina in the eye) or lung damage.
Hence, oxygen delivery must be titrated based on the newborn's condition, guided by pulse oximetry and clinical signs.
Striking the right balance ensures oxygen is used effectively to support life while minimising risks, emphasising its critical yet controlled role in newborn resuscitation.
