by David Gutierrez
October 15 2008
(NaturalNews) While beta blockers do decrease the risk of heart attacks during surgery, they actually increase a patient’s risk of dying anyway, according to a study conducted by researchers from McMaster University in Canada and published in The Lancet.
“There is a real potential that beta blockers are causing serious harm in the surgical setting,” researcher P.J. Devereaux said. “If my mother was undergoing surgery and given a beta blocker, I would be extremely upset based on this evidence.”
Beta blockers counter the effects of stress hormones known as catecholamines, which are known to be produced during major surgery. These hormones can increase blood pressure and heart rate to dangerous levels, inducing heart attacks. For this reason, many surgeons have taken to prescribing the drugs before major surgical procedures.
But in some patients, surgery instead induces shock and a drop in blood pressure. In these patients, beta blockers can be dangerous.
In the current study, researchers studied more than 8,000 surgical patients in 23 countries. All the patients had clogged arteries or were at risk for them, but none were being operated on for their hearts. Half the patients were given a beta-blocker known as metoprolol before their surgery; the other half were given a placebo.
Based on their data, the researchers concluded that using beta blockers would prevent 15 heart attacks for every 1,000 patients but would lead to eight more deaths and five strokes than not using the drugs. The drugs produced abnormally low blood pressure in 53 percent of patients and an abnormally slow heart beat in 42 percent.
The researchers calculated that widespread use of beta blockers before surgery may have contributed to more than 800,000 deaths to date.
Peter Weissberg, medical director of the British Heart Foundation said that the study highlights the importance of actually testing drugs’ effects with large clinical trials, rather than assuming how they will operate based on theory.