How does CPAP work

This blog covers what CPAP stands for and how it works. CPAP stands for Continuous Positive Airway Pressure. It is a therapy device that applies mild air pressure on a continuous basis to keep the airway continuously open. CPAP is the most effective treatment for obstructive sleep apnea. In fact, CPAP is a more effective treatment than an oral appliance or surgery due to CPAP opening up the entire airway no matter what the cause of the obstruction. Oral appliances and surgery target particular areas of the airway, so are sometimes not as effective.cpap

Obstructive sleep apnea occurs when the upper airway becomes narrow as the muscles relax naturally during sleep. This reduces oxygen in the blood and causes arousal from sleep. The CPAP machine stops this phenomenon by delivering a stream of compressed air via a hose to a mask splinting the airway (keeping it open under air pressure) and prevent the airway from collapsing.

CPAP also may be used to treat preterm infants whose lungs have not yet fully developed. For example, physicians may use CPAP in infants with respiratory distress syndrome. In some preterm infants whose lungs haven’t fully developed, CPAP improves survival and decreases the need for steroid treatment for their lungs. CPAP is also used in the hospital setting for adults to improve the ability of the lungs to exchange oxygen and carbon dioxide and to decrease the work of breathing.

The CPAP machine blows air at a prescribed pressure (also called the titrated pressure). The titrated pressure is the pressure of air at which most of apneas (stops in breathing) and hypopneas (shallow breathing) have been prevented, and it is usually measured in centimetres of water  (cmH2O). A typical CPAP machine can deliver pressures between 4 and 20 cmH2O.

The mask required to deliver CPAP must have an effective seal, and be held on very securely.  There are three types of masks. Nasal pillow, nasal and full face mask. Nasal pillow masks maintain its seal by being inserted slightly into the nostrils and being held in place by straps around the head. Nasal masks cover the nose and full face masks cover your nose and mouth.  Both masks “float” on the skin like a hovercraft, with thin, soft, flexible “cushion” made out of silicone. Headgear is used to keep the masks secure on the face. For more information on CPAP and masks and their features check

By Bahareh Ezzati (RRT)


Heart Diseases and Sleep Apnea

Did you know about one half of patients who have essential hypertension have obstructive sleep apnea? Research shows that obstructive sleep apnea increases both daytime and night time ambulatory blood pressures. Heart failures, Strokes, Coronary heart disease, and Pulmonary hypertensions are other cardiovascular diseases related to OSA.heartSleep apnea affects many of the complex systems of our bodies and is associated with other serious conditions like high blood pressure. Many people think sleep apnea is as simple as snoring, but it’s really much more than that.

Constantly depriving your body of oxygen each night has a tremendously negative impact on your body. Normally, your blood pressure falls at night. If you have sleep apnea, your blood pressure may not fall, which can lead to high blood pressure. Every time your oxygen level drops, this raises your blood pressure and causes an adrenaline surge. This puts increased stress on your heart because it has to work harder to normalize your blood pressure. The more severe your sleep apnea, the greater the risk of high blood pressure. Nevertheless, treatment of OSA with CPAP significantly reduces daytime blood pressure in patients with resistant hypertension.

OSA affects the heart in 3 different stages of apnea episodes. The first during systemic hypoxemia (drop in oxygen level in blood stream). As a result, sympathetic nervous system activity (fight and flight effect) increases, which in turn increases peripheral vascular resistance and increases heart rate and blood pressure. The second effect is due to negative intrathoracic pressure. During apnea episodes respiratory effort is still ongoing, which creates suctioning effect in your thoracic cage. This suctioning mechanism affects cardiac preload and after load due to which cardiac blood output is affected. The third effect is during patients arousals from sleep. Arousals occurs to terminate apnea’s episodes and it associates with high level of cardiac and respiratory activity. This may also contribute to the development of post-apneic surges in blood pressure and heart rate as well as sleep fragmentation.

High blood pressure, like sleep apnea isn’t normally something you can detect on your own. If you have sleep apnea, you likely don’t know about it unless other people tell you that you’re keeping them up at night by snoring or temporarily stopping breathing when you sleep. If someone tells you that you do either of these things, it’s important to take it seriously because sleep apnea is linked to so many other life-threatening conditions like high blood pressure. To discuss your signs and symptoms and/or to do diagnostic tests contact Cansleep Services Inc.

By Bahareh Ezzati (RRT)

Diabetes & Sleep Apnea

Are you diagnosed with diabetes and sleep apnea and wondering if these two are linked? If so, this blog answers your questions.

Sleep apnea and diabetes are strongly associated with one another. Clinical research shows that approximately 50% type 2 diabetics have also been diagnosed with sleep apnea.

Researchers in Toronto’s Sunnybrook Hospital took healthy volunteers and sleep deprived them in the laboratory, and they showed as if they were in the pre-diabetic state after sleep deprivation. This was only after one week of sleep deprivation and it wasn’t total sleep deprivation,it was four and a half hours in bed. Sleep deprivation, short sleep duration, increases your risk for type 2 diabetes.

Research indicates that sleep apnea is independently associated with insulin resistance. However, it is not clear what mechanisms of action are responsible. Researchers are evaluating a few theories such as:

  • Not getting to or staying in REM (deepest) stage of sleep, which is the time for hormones to get regulatedDiabetic and CPAP
  • Accumulation of sleep debt due to sleep fragmentation
  • Recurrent  hypoxia (low oxygen level) leads to the impairment in
    homeostasis (lack of maintenance of the blood glucose equilibrium), leading to insulin resistance
  • Elevated levels of the hormone cortisol, which is released under conditions of stress in the body, can contribute to increased energy production and sympathetic nervous activity, leading to excessive blood sugar levels and reduced insulin sensitivity
  • Increased sympathetic nervous activity cause the release of glucose from the muscles into the bloodstream to activate an arousal from sleep, and result in residual circulating glucose in blood  

With type 2 diabetics who have sleep apnea, CPAP usage can improve their glucose control. Within 48 hours, significant improvements have been demonstrated in insulin sensitivity using CPAP therapy. After-meal blood glucose levels can be reduced with compliant CPAP therapy, which suggests that sustained CPAP use may be an important therapy for diabetes patients with sleep apnea.

One of the goals of the clinicians at CanSleep services is to insure patients pay extra close attention to the risk factors for diabetes if they have sleep apnea, and making sure they are doing all they can to ensure healthy sleep if patients happen to be diabetic. 

By Bahareh Ezzati (RRT)


Are you still tired despite of treating your Insomnia and/or sleep apnea? Do you know what narcolepsy is, and what is the treatment for it? The focus of this blog is on narcolepsy.


Bored man at the wheel of his car sleeping


Narcolepsy is a neurological disorder that affects the control of sleep and wakefulness. People with narcolepsy experience excessive daytime sleepiness and episodes of falling asleep during the daytime which is out of their control and can occur during any types of activities at any time of the day. The cause of narcolepsy is not known. Some scientists link narcolepsy with genes that control the production of chemicals in the brain that may signal sleep and awake cycles and deficiency in the production of the same chemical called hypocretin by the brain.

Typically, we enter the deepest stage of sleep called REM (rapid eye movement) after 90 minutes. People suffering from narcolepsy enter REM stage of sleep almost immediately in the sleep, as well as periodically during the waking hours.

Narcolepsy usually begins between the ages of 15 and 25, but it can become apparent at any age. Common signs and symptoms are as followed: Excessive daytime sleepiness, Cataplexy (sudden loss of muscle tone), Hallucinations and Sleep paralysis (temporary inability to move or speak).

To diagnose and confirm narcolepsy two tests are necessary: PSG (Polysomnogram is an overnight sleep test to screen abnormality in stages of sleep) and MSLT (the Multiple Sleep Latency Test is performed during day to measure a person’s tendency to fall asleep).

There is no cure for narcolepsy. The treatment is to control the symptoms of the disorder. Sleepiness is treated with stimulants as amphetamine, while the symptoms of abnormal REM sleep are treated with antidepressant drugs.Xyrem also helps people with narcolepsy get a better night’s sleep. Lifestyle changes such as avoidingcaffeine, alcohol, nicotine, and heavy meals; scheduling daytime naps (10-15 minutes in length), regulating sleep schedules, and establishing a normal exercise and meal schedule may also help to reduce symptoms.

By Bahareh Ezzati (RRT)

Apnea-Hypopnea Index (AHI)

Have you noted term AHI on your CPAP report and wondered what does it mean? Do you know what the normal range for AHI is? Do you know the reason why AHI may vary each night or why is it higher when you are taking a nap? If so, continue reading to get your answer.

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It’s common for people using CPAP to still experience apneas while they sleep. CPAP, oral appliances and other sleep apnea treatment options are designed to reduce your AHI, but not necessarily eliminate them completely, since it’s normal for everyone to have up to four apneas an hour. The initial goal is to get AHI below 5. Keep in mind it may take a little time to reach to the target AHI if you’re new to CPAP or even trying a new mask. In some patients with severe sleep apnea a higher AHI is acceptable as long as they’re feeling more rested each morning and experiencing fewer symptoms. For example: for someone with initial AHI of 45, AHI of 8 with CPAP might be considered normal.

It’s common for AHI to vary from night to night.

It is also normal for people that take a half-hour nap to have higher AHI since Your AHI measures the number of apneas and hypopneas you experience per hour, not the total number. For example, if you nap for a half hour and have an AHI of 8, that means you only experienced four apneas which is still within the normal range.

There are three reasons that your AHI may rise.  First is mask leak. If air is escaping your CPAP mask, you’re not getting all the air pressure needed to keep your airway open and as a result AHI rises. Second is consumption of alcohol, narcotics and drugs which increases obstruction and as a result AHI. Third is development of central or complex sleep apnea. In central sleep apnea, the brain is not telling your body to breathe. This is caused by a dysfunction in the central nervous system, not a physical obstruction, and requires a different type of machine and PAP therapy.

If your AHI was stable, but it is suddenly increasing over the past few weeks or months, you should book a follow up appointment at CanSleep.

By Bahareh Ezzati (RRT)

Obesity & Sleep Apnea

Did you know obesity is an important risk factor for OSA and weight loss can reduce apnea severity and even lead to resolution in some patients?

Obese man's waist

Even though obesity usually is not the cause of sleep apnea, it makes the severity of sleep apnea greater. There are different factors that may cause sleep apnea to be more severe in the heavier population such as: increases in neck circumference and fat deposit around the upper airway, increase in upper airway collapsibility and reduction in lung volume (which leads to a loss of caudal traction on the upper airway and an increase in pharyngeal collapsibility).  Obesity and OSA form a vicious cycle where each results in worsening of the other. Obstructive sleep apnea in turn could worsen obesity because of sleep deprivation, daytime somnolence, and disrupted metabolism. It also could increase appetite and caloric intake by changes in hormones such as ghrelin, leptin and orexin.

Let’s look at a few more facts:

  • 10% change in body weight is associated with a parallel change of approximately 30% in the apnea-hypopnea index (AHI), which is the major index of sleep apnea severity.
  • The chance of that an obese male has sleep apnea is 2-3fold of a female because of the fat distribution in men. Male predominantly have central fat deposition pattern around the neck, trunk and abdominal viscera compare with women.
  • Increases in visceral fat with age may also account for an increase in sleep apnea occurrence in middle-aged and older men and in postmenopausal women.

Effective CPAP therapy may lead to weight loss by a few mechanisms such as increased physical activity and increased responsiveness to Leptin.

Talk to your clinical specialist at CanSleep to find out your AHI and if it has changed over the years with aging and gain/loss weight.

By Bahareh Ezzati (RRT)

Sleep & Light Therapy


Did you know that 35 million Americans suffer from Seasonal affective disorder (SAD)? Did you know that light therapy could help people suffering from SAD or chronic Insomnia as well as people that have difficulties adjusting to shift work and air travel?

Researchers have discovered a new type of cell in the eye that is directly related to the brain’s “body clock”. Melanopsin photoreceptor responds to a very specific color of blue light and tells the body clock when to produce the hormones that control sleep/awake, mood and energy cycles. Therefore, exposure to bright light stimulates nighttime melatonin production, whereas ordinary room light is not sufficiently intense to be effective.

Those with weak circadian rhythms need a very bright stimulus of light to reset their body clock each day. When they don’t receive this light signal, their body clock either speeds up (advance) or slows down (delay), which in turn causes the production of the wrong hormones at the wrong time of day and this can lead to mood and sleep disorders. Bright light (10000luxitensity) has been found to be the only effective means of shifting circadian rhythms. If you have difficulties falling asleep, your body clock is delayed, but if you fall asleep easily but wake up few hours later or too early in the morning (common in the elderly), your body clock is advanced.

Bright light exposure in the morning should advance circadian rhythms (shift then to an earlier time) and bright light exposure in the evening should delay circadian rhythms (shift them to a later time).

For jet-lag adjustment, it is much easier to reset one’s body clock before arriving in the new time zone. Wearing sunglasses for the first few days in the morning while resetting the body clock to an earlier time is also suggested. When traveling east, one should advance his one’s body clock (shifting from day to night). The number of time zones traveled corresponds to the hours needed to shift.

For people who want to adapt to shift work they could accelerate circadian shifting with melatonin. This can help move the body clock as much as four to six hours each day in either direction.

Talk to your sleep specialist to get a right instruction on how and when to use light therapy to overcome your insomnia and/or mood disorder.

By Bahareh Ezzati (RRT)

Humidity or No Humidity!!

Should I use my CPAP’s humidifier or not? What is the purpose of the CPAP humidifier? Can the humidifier help me with my allergies? If these are some of the questions on your mind, this paper has the answers.CNYrbv-XAAAjagO

The CPAP humidifier is not only used in the cold and dry season but it can also be helpful in regards to allergy symptoms such as dryness caused by congestion and the inflammation of the nasal passages due to hay fever and other environmental allergies.

Your nose is responsible to warm the air so when it reaches your lungs, it is at body temperature; and to secrete fluid to help clear out allergens and other unwanted particles.

Using CPAP without humidification means your nose has to work extra hard to warm all this extra air and also produce even more fluid to maintain its moisture to clear out allergens. Sometimes the nose will keep overproducing fluid up to 3hrs after you stop using CPAP. This is known as nasal reactive syndrome.

Using a CPAP’s humidifier prevents the overworking of your nose and enough fluid remains to fight allergens, which in turn helps lowering congestion and inflammation caused by allergens.

Nasal cavities swell up during an allergic reaction, and if increasing humidity level doesn’t help and you are using a nasal pillow mask, consult with your clinician at CanSleep.  Swollen nasal cavity (cavities) can push out the nasal pillow enough to create leak and discomfort, so using a nasal or a full face mask during allergy season is may be a better option.

It is recommended to use CPAP with a humidifier all year round. However, depending on the humidity level of the place you live, you might be able to bypass humidity. Some people do not get dry nose or runny nose by bypassing humidity. If you are travelling a lot and would like to bypass taking the humidifier part of your CPAP, you should try the CPAP without humidity for a while to see your body’s reaction first.

By Bahareh Ezzati (RRT)

Deviated Septum & Sleep Apnea

Do you have deviated septum and wondering how it affects your CPAP therapy? This post helps you understand what is deviated septum and how is it affecting your sleep apnea and CPAP therapy.

nose plastic surgery preparation

Deviated septum is due to a misalignment in the nasal passage’s bone and the cartilage dividing nose that makes one nasal cavity larger than the other. Deviated septum can be hereditary or can be due to injuries, especially sports injuries.

Some of the symptoms are:  Obstruction of one or both nostrils, nosebleeds, noisy breathing, and awareness of when obstructions in your nasal cavity switch from one nostril to the other. Keep in mind that these symptoms could be caused by other temporary or chronic conditions, so make sure you are diagnosed first before starting a treatment.

ENT specialist or your physician could diagnose you by either using endoscope or looking up your nose with a bright light to visually examine your septum.

Usually no treatment is required unless you are symptomatic. For instance if you are experiencing constant nosebleeds or sinus infections the suggested treatments are as follows:

  • An adhesive strip to keep the nasal passages open.
  • Medications: It only treat symptoms, not the condition itself. For example nasal steroids, decongestants and antihistamines.
  • Septoplasty: Comprises a surgery by making an incision in the septum that straightens the nasal bone and cartilage.

Deviated septum can cause sleep apnea by restricting the nasal passage to the upper airway (aka upper airway resistance). Also, if the patient already has an obstruction in his/her airway due to other factors such as larger tongue or uvula, the restricted nasal passage makes it worse. Apneas increase and symptoms are easier to notice.

If you have a deviated septum, mention it to your therapist at CanSleep to see if you can benefit from a different mask type. For example using a full face mask instead of a nasal pillow for more comfort.

By Bahareh Ezzati (RRT)

Sleep Apnea & Pregnancy

Did you know that not treating Sleep Apnea during pregnancy could put your infant at risk? Did you know during pregnancy the majority of women experience alterations in sleep? Do you know that you might need to alter your sleep or CPAP therapy during pregnancy?pergnancy

The physiologic and biochemical change of pregnancy may place women at risk for developing specific sleep disorders such as obstructive sleep apnea and restless legs syndrome. Pregnant women’s sleep pattern and duration also changes due to hormonal changes mainly during the first trimester. Overall studies show mean increase in sleep duration of 0.7 hours is common; however, due to fatigue or nausea and vomiting, sleep is more disturbed. During the third trimester the REM (deepest stage of sleep) is shorter and the majority of women start taking mid-day naps. Other physiological changes such as edema of the nasal mucosa can lead to increased airflow resistance and airway narrowing which exacerbates sleep apnea.

Sleep apnea is a risk factor for pregnancy-induced hypertension which can increase the risk of premature delivery, feral growth retardation and maternal mortality.  Studies shows apnea episodes causes fetal heart rate to decelerate.

Women may experience severe persistent insomnia which could fail to respond to sleep hygiene measures or targeted therapies. However trial of behavioral therapies is strongly recommended.

Sleeping on your side is strongly suggested to reduced severity of sleep apnea as well as it avoids uterine compression of the inferior vena cava and potential compromise of cardiac output. To get assistance in sleeping on your side you could obtain bumper belt from CanSleep services which has stuffed pockets that prevents you from sleeping on your back.

Some women diagnosed with OSA require higher therapeutic pressure (about 1-2 cmH2O higher). Talk to your therapist at CanSleep to perform overnight oximetry to check for desaturation and need of CPAP titration.

By Bahareh Ezzati (RRT)