Two simple fixes might reduce bleeding after caesareans

Cosmos Magazine


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By Cosmos

Postpartum haemorrhage – severe bleeding after birth – is the leading cause of maternal mortality worldwide. Women having caesarean sections are particularly at risk.

A team of US researchers believes there are two measures which could drastically reduce the risk of postpartum haemorrhage.

One involves using a cheap medication to help the uterus contract after surgery, while the other is an electronic system that prompts doctors to regularly check for signs of haemorrhage and warns them if they appear.

The researchers have presented their studies at the American Society of Anesthesiologists’s 2023 annual meeting.

The first study involved a double-blind, randomised-control trial of a calcium chloride solution: a cheap and safe medication which doesn’t need refrigeration.

The researchers hoped that calcium chloride would help with “uterine atony”: when the uterus stays soft after delivery and fails to contract, meaning that blood vessels don’t get compressed. Uterine atony is responsible for 80% of postpartum haemorrhages, according to the researchers.

They gave either calcium chloride or a placebo to 120 women who’d just had a caesarean section. They found that calcium chloride reduced bleeding by an average of more than 200mL (a haemorrhage is defined as the loss of 500mL of blood).

Women were also less likely to haemorrhage at all if treated with calcium chloride: 57% in the placebo group had postpartum haemorrhage and 15% needed a blood transfusion, compared to 40% in the calcium chloride group haemorrhaging and 8% needing a transfusion.

“New treatments to treat uterine atony are desperately needed,” says Dr Alla Yarmosh, lead author of the study and clinical assistant professor in anaesthesiology at Stanford University.

“This is the first time an infusion of calcium chloride has been studied as a possible treatment to help the uterus contract after caesarean delivery and decrease bleeding in those patients.

“If our findings are confirmed by larger studies, it would be an easy technique for institutions to implement since anaesthesiologists run infusions during surgery regularly.”

Calcium chloride could also be used in low-resource settings, where the risk to maternal health is higher.

The second study from the US researchers involves software that sends an alert to anaesthesiologists’ electronic health records at intervals after birth, asking for a “uterine tone” score of 1-10 from the obstetrician. A score of 6 or below is a sign that haemorrhage is more likely because the uterus isn’t contracting well.

“Bleeding during a caesarean delivery is a high-stakes, high-risk situation, and when it occurs, the obstetrics and anaesthesia teams must work together to rapidly prevent and treat ongoing bleeding,” says Dr James Xie, lead author of the early warning study and clinical assistant professor of anaesthesiology, perioperative and pain medicine at Stanford University, California.

“Studies have shown that rapid recognition and management are essential to improving outcomes.”

The researchers tested the system among 70 different obstetricians over 8 months, across more than 1,000 caesarean deliveries.

At 12 minutes after birth, 18% of women had scores of 6 or below: 77% of these experienced haemorrhage, 46% experienced major haemorrhage and 25% needed a blood transfusion.

“Our research shows that this simple scoring system is a very meaningful, easy way to ensure that if the uterus is contracting poorly and there is a risk of haemorrhage, it will be recognized by their health care team early,” says Xie.

“In the future we can further refine models that predict when women are at high risk of bleeding around the time of delivery to help physicians be prepared to manage bleeding caused by poor uterine tone.”

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