Fainting: When Is It Serious?

By Jane Farrell

Emergency-room physicians, using a simple questionnaire, could uncover the dangerous hidden conditions that make some people faint, according to a study published today in the Canadian Medical Association Journal.

Fainting is fairly common – 35 to 40 percent of people faint at least once in their lives. But for about ten percent of people who visit the emergency room for fainting it can be a symptom of a potentially life-threatening condition like arrhythmia, or heart rhythm disturbance.

A team of researchers at The Ottawa Hospital and the University of Ottawa have created a screening tool to help emergency doctors predict the risk of a patient experiencing adverse events from these hidden conditions within a month of fainting. These include irregular heartbeat, heart attacks and even death. If the risk is high, then doctors would do a thorough evaluation in the hospital before sending the patient home.

“Fainting is a big problem,” said Dr. Venkatesh Thiruganasambandamoorthy, an emergency physician and scientist at The Ottawa Hospital and an assistant professor at the University of Ottawa. “The way fainting patients are examined in emergency rooms varies greatly between physicians and hospitals. We hope that this screening tool will make the process more consistent and improve the detection of serious conditions related to fainting.”

Thiruganasambandamoorthy also notes that most fainting patients admitted to hospital do not need to be there. These patients can spend four to seven hours in the emergency department before a decision to discharge them is made. “If our tool can discharge low-risk patients quickly and safely, then I think we can reduce emergency room wait times and open up those resources to other patients.”

Of the 4,030 fainting patients his team observed across six Canadian emergency rooms, 147 suffered a serious event in the month after discharge. This is largest study of its kind in the world.

After following up with patients and analyzing clinical findings from emergency doctors Thiruganasambandamoorthy and his team found nine factors that physicians can plug into a screening tool. Added together, these factors give the patient’s total risk of an adverse event, from very low to very high.

These factors include:

• The physician’s diagnosis of the cause of fainting
• Signs of a common and harmless variety of fainting, such as being in a warm or crowded place, standing for a long time, or feeling intense fear, emotion or pain
• A history of heart disease
• Abnormal electrocardiogram (ECG) measurements
• Higher levels of troponin, a protein specific to heart muscle

The tool is currently being validated in emergency rooms across Canada in a study funded by the Canadian Arrhythmia Network of Canada. Once validation is complete, Dr. Thiruganasambandamoorthy hopes to make the tool available online and as an app.