Something as simple as a blood test could help predict a patient’s chances of surviving after surgery, a study has suggested.

By looking at the levels of protein in the blood it may be able to assist doctors in deciding which patients require more intensive monitoring after having had their operation.

Experts from James Cook University in Middlesborough made the discovery after they tested whether the levels of troponin – a protein that is released into the bloodstream during a heart attack – could predict long-term survival after surgery.

Researchers, who are presenting their study to the British Cardiovascular Society conference in Manchester, measured the level of troponin in blood samples taken from 993 patients before they underwent elective or emergency surgery – none of the patients underwent cardiac surgery.

They used a troponin test which is routinely used in accident and emergency departments to diagnose a heart attack.

Quarter of the patients who had troponin levels of 50 nanograms per litre (ng/l) or over before their surgery died within six months, the researchers found.

This figure rose to 37% dying within a year of their operation.

Meanwhile, among patients who showed pre-operative troponin level of less than 17ng/l, just 2.5% died within six months.

This figure rose to 3.7% of patients with lower levels of the protein dying within 12 months of their surgery.

The link between the raised troponin levels and a higher chance of death following surgery is not yet understood but the researchers suggested that a high troponin level may show that a person is suffering from underlying inflammation.

“By helping us to better predict how patients will fare after surgery, this test may help doctors to identify patients who could benefit from additional tests and medication to get them ready for their surgery and more intensive monitoring as they recover after their operation,” said Dr Matthew Jackson, research fellow at James Cook University Hospital.

“Now we need to find out why troponin levels are raised in some patients before surgery, and why these patients are more likely to die, in order to identify treatments that could reduce the risk of death following non-cardiac surgery.”

Commenting on the study, Professor Metin Avkiran, associate medical director at the British Heart Foundation, said: “Troponin tests detect injury to heart muscle and are used to diagnose a heart attack.

“This study suggests that an elevated troponin level in the blood before non-cardiac surgery, in the absence of a heart attack, is predictive of poor patient survival during the first 12 months after such surgery.

“If we can understand the underlying causes of heart injury in such patients, their treatment may be tailored to improve outcome after non-cardiac surgery.”