The opening of the Sleep Country Canada Sleep Medicine Labs at TGH has reminded everyone that sleep apnea is a serious health issue, but Dr. Frances Chung needs no reminder. 

It is widely known that Obstructive Sleep Apnea (OSA), a sleep disorder in which airways become obstructed during sleep, causes loud snoring, but it's also linked to more trying health concerns such hypoxia, restless sleep, morning headaches, fatigue and drowsiness during the day and can even increase blood pressure and heart rate in patients with heart failure. 

Chung, an anesthesiologist at TWH, deals with a lesser-known issue for those suffering from OSA, its role in perioperative complications. Dealing with OSA has been a major part of Chung's work for years—the disorder plays a role in blood pressure and is thus an important consideration for determining which anesthetics should be used on patients undergoing surgery.

"Anesthetists adjust the medication we give to patients if we determine that they are high risk for OSA," says Chung. "Depending on the patient, we may adjust the anesthetic method, providing more regional anesthesia and ensuring that the drugs used are more short-acting drugs so that the patient can recover faster."

Dr. Frances Chung image 
Image credit: Arnand Maharaj

But one of the biggest challenges for anesthesiologists dealing with OSA patients is that most don't even know they suffer from it—90% of sufferers are undiagnosed. With that lack of awareness in mind, Chung devised the STOP-Bang method—a brief questionnaire that is now used in many pre-operative clinics and sleep labs worldwide.

Chung believes that education is key to making the risks of undiagnosed OSA a more recognized issue. 

"Patients, surgeons, anesthetists and nursing staff—everyone should be aware of the risks and be concerned that patients at high risk for OSA be assessed," says Chung. "I think if you treat the OSA, the medical conditions get a little better, or perhaps the hypertension may be less significant, or the congestive heart failure may get better. "

Complications from OSA will not end outside the OR. Post-operative follow-up care is also impacted by OSA affliction, not just for the issues mentioned at the outset, but also because drugs like morphine suppress breathing, so post-operative pain management needs to make considerations for those with severe OSA. 

As obesity rates continue to climb, this has become a more prevalent issue, but fortunately with the work of researchers like Dr. Chung, we might all be able to sleep a little easier.

STOP – Bang Method

Test yourself to see if you're at risk of OSA.

S: Do you Snore loudly?
T: Do you often feel Tired, fatigued, or sleepy during daytime?
O: Has anyone Observed you stop breathing during sleep?
P: Do you have or are you being treated for high blood Pressure?
BBody mass index greater than 35
AAge greater than 50
NNeck circumference greater than 40cm
GGender male

Three or more positive answers means a patient is at risk of OSA. Six or more positive answers indicates a high risk.

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