Obstructive Sleep Apnea

Transcription

1 Obstructive Sleep Apnea Introduction Obstructive sleep apnea is an interruption in breathing during sleep. It is caused by throat and tongue muscles collapsing and relaxing. This blocks, or obstructs, the flow of air to the lungs. The amount of oxygen in your blood drops when your lungs can t get enough air. The brain automatically wakes you up and normal breathing starts again, often with a loud snort or a choking sound. About 18 million Americans have sleep apnea. It is a serious medical condition for two main reasons. First, as the brain keeps waking up to give orders to the muscles to open the airway. It never has the chance to go into deep refreshing sleep which causes you to always be tired and sleepy. Second, low oxygen levels cause your heart to work harder. This weakens the heart and causes dangerous problems such as heart disease and strokes. If you snore, you need to find out if you have sleep apnea. Not all snoring is caused by sleep apnea. If your doctor told you that you have sleep apnea, you need to treat it to improve your quality of life and prevent diseases, some of which could be fatal. This reference summary explains obstructive sleep apnea. It discusses its causes, symptoms, dangers, and treatment options. Sleep Before explaining how sleep apnea affects your sleep and health, let s review a few facts about sleep. These facts will help you better understand how serious sleep apnea can be. An adult person needs 7 to 8 hours of sleep. If a person does not sleep well, his or her physical and mental abilities are affected the next day. Over the long run, the immune system becomes weak. The immune system helps fight germs. 1

2 Quality of sleep depends not only on number of hours of sleep per day, but also on how deeply a person sleeps. While we sleep, our brain stays very active. Brain activity goes through cycles. Every cycle takes about 90 to 110 minutes and includes the following 5 stages. 1. stage 1 Drowsiness 2. stage 2 Light Sleep 3. stage 3 Deep Sleep 4. stage 4 Slow-Wave Deep Sleep 5. REM sleep Rapid eye movement During stage 1, or light sleep, we drift in and out of sleep and can wake up easily. Our eyes move very slowly and muscle activity slows. In stage 2 sleep, eye movement stops and brain activity slows down. In stages 3 and 4, extremely slow brain waves appear. It is very difficult to wake someone up during stages 3 and 4, which together are called deep sleep. There is no eye movement or muscle activity. People awakened during deep sleep do not adjust immediately and often feel groggy and disoriented for several minutes. Some children experience bedwetting, night terrors or sleepwalking during deep sleep. During REM sleep, our breathing becomes more rapid, irregular and shallow. Our eyes jerk rapidly in various directions, and our limb muscles become temporarily paralyzed. Our heart rate increases, our blood pressure rises and males develop penile erections. When people wake up during REM sleep, they often describe having dreams. The REM stage of sleep is very important for the body to rest and get refreshed. For example, rats normally live for 2 to 3 years but in studies, those deprived of REM sleep live only about 5 weeks! Every single cell in the body needs oxygen to produce energy. Blood carries oxygen to the cells of the body. As we breathe, blood cells load up with oxygen in the lungs. The heart then pumps the oxygen to all parts of the body. 2

3 As we breathe in, air moves through the nose or mouth to the lungs. In our throat, air travels through the windpipe. The throat is a complex structure that has muscles around it. These muscles support the soft palate, the uvula, the tonsils and the tongue. The uvula is the piece of tissue dangling down in the back of your throat when you look into your open mouth in the mirror. The brain controls breathing. We breathe automatically without having to think about it. During sleep apnea, a person stops breathing, which causes the brain to wake the body up from deep sleep so it can breathe again. What is it? Obstructive sleep apnea occurs when the muscles in the throat relax and drop down. In most people this is more likely to happen when they sleep on their back. Relaxed Airway Creating Obstruction When the muscles in your throat relax, Lungs your airway narrows or closes. If it narrows, it causes less air to go to the lungs. If it closes, airflow to the lungs stops completely. In either case, the level of oxygen in your blood decreases. Your brain senses that breathing is interrupted and automatically sends a signal to wake you from sleep. Your brain is aroused, the muscle of the throat becomes firm again and you can start breathing again. This happens so fast that most people with sleep apnea don t actually feel or remember waking up! Sleep apnea can be mild or severe. The level of severity depends on the number of apnea episodes. Each episode goes through muscle collapse, breathing interruption and then a brief awakening. This could happen 20 to 30 times or more each hour and all night long! Every interruption of breathing usually lasts 10 to 20 seconds, but could be as long as 60 seconds! A person who wakes up 20 times an hour or more may never be able to reach the deeper stages of sleep, especially REM sleep. The body never rests well. Because most people with sleep apnea don t notice the brief, sudden awakening and snoring, 3

4 they don t realize they have the problem. They think when they get 7 to 8 hours of sleep that they slept enough, not knowing that it was bad quality sleep. From waking up so many times each night, sleep apnea patients are always sleepy and drowsy. They may also experience personality changes, such as irritability and depression. Most people who have sleep apnea have obstructive sleep apnea. However, there is another type of sleep apnea called central sleep apnea. In central sleep apnea, a person stops breathing suddenly too. However, the cause is not an obstructed windpipe; it is the failure of the brain to send signals to the body to breathe. People with central sleep apnea are more likely to remember waking up to breathe. They may also feel shortness of breath and headaches as they wake up. Most people with obstructive sleep apnea may not be aware that their sleep was interrupted. It is usually another person sleeping in the same room that notices the sudden snort and complains about it. Some people with sleep apnea have airflow to the lungs only partly blocked, which is called hypopnea. This is still serious because the body is not getting enough oxygen. This may still cause a brief, sudden awakening as the brain senses a low oxygen level. It also causes the heart to work harder to pump more blood so the body can get the oxygen it needs. Complications Sleep apnea is a serious medical condition for several reasons. First, when your sleep is interrupted throughout the night, you can be drowsy throughout the day. This reduces your quality of life and mental and physical capabilities. Because they are always tired and sleepy, people with sleep apnea are at a higher risk for accidents, particularly car crashes. Driver drowsiness is responsible for around 100,000 motor vehicle accidents and 1,500 deaths each year in the USA. Patients with severe, untreated sleep apnea are 2 to 3 times more likely to have automobile accidents than people without sleep apnea. 4

5 The lack of quality sleep may cause people with sleep apnea to experience personality changes. This includes irritability, forgetfulness, mood swings, anxiety and depression. Sleep apnea could cause a decrease in mental ability. This includes forgetfulness and inability to concentrate. Children who have sleep apnea are often diagnosed as having attention deficit disorders. In people with sleep apnea the heart has to work harder to provide the oxygen the body needs. With the heart working harder, a person with sleep apnea could have heart and circulatory problems in the long run. Sleep apnea can lead to: High blood pressure Irregular heartbeats Increased risk of heart attacks or stroke, which can be fatal Sleep apnea can lead to impotence. This is due to a combination of poor blood circulation, fatigue and personality changes. Impotence or erectile dysfunction is the inability to have a satisfactory erection. People with sleep apnea may be more sensitive to sedatives, especially strong ones given during the course of anesthesia. This increased sedation could potentially be life threatening. For this reason, it is extremely important to let your healthcare providers know about the possibility that you may have sleep apnea. Sleep apnea also affects bed partners or roommates. It is usually the bed partner and not the person who has sleep apnea that notices the snoring and the sudden loud snorts throughout the night. The bed partner may become sleep deprived too if he or she does not move to another room. Sleep apnea may strain the relationship with your bed partner. Causes Sleep apnea is an interruption in breathing during sleep. This happens when muscles and tissues around the windpipe collapse. Why does this happen to some people and not to others? This section answers this question. 5

6 If you are overweight, the soft tissue in your throat, as well as your tongue, becomes fatty. This makes it hard to keep the throat open as you sleep on your back. That is why doctors first recommend losing weight for overweight people who have sleep apnea. However, not all sleep apnea is caused by excess weight. Your throat muscles and tongue may relax more than normal. One of the first things doctors recommend to stop sleep apnea is to NOT drink alcohol or take sedatives at night. These substances cause the muscles of the throat to relax more than normal. Muscle tone and firmness decreases as we age. This is true of muscles and tissues around the throat as well. That is why sleep apnea is also associated with aging. Sleep apnea is about three times more common in people over 65. However, sleep apnea can occur at any age, even in children. The shape and anatomy of the neck and throat can be a factor of sleep apnea. Like the shape of the nose and ears, these traits are inherited from parents. A person with a narrow windpipe is more likely to have sleep apnea. A person with a neck bigger than 17 inches around is more likely to have sleep apnea. This may explain why men are more likely than women to have sleep apnea. Smoking can cause airway tissue to become inflamed and swollen. That may explain why smokers are more likely to have sleep apnea than nonsmokers. Some people with mild sleep apnea can treat sleep apnea after they stop smoking. Sometimes the tonsils and adenoids become enlarged, causing airways to be partially blocked as the person sleeps. Doctors can recommend surgery to remove enlarged tonsils or adenoids in people with sleep apnea. If someone in your family has sleep apnea, you are more likely to develop sleep apnea than someone without a family history of the condition. Obstructive sleep apnea can occur in children. If your child snores, you should discuss it with your child's doctor or health care provider. 6

7 It is important to remember that there is a non-obstructive type of sleep apnea caused by the brain s failure to send signals to the body to breathe. This module discusses the obstructive type. Signs There are 5 common signs of sleep apnea: 1. Loud snoring 2. Choking or stopping breathing during sleep 3. Loud snort as if gasping for air 4. Waking up often 5. Sleepy during the day Not all snoring is sleep apnea. How bad a person s choking or stopping breathing is also depends on how severe the sleep apnea is. However, the pattern of sleep apnea is clear: a sleeping person seems to stop breathing, then suddenly gasps for air and sometimes makes a loud snort. A person with sleep apnea may never feel the symptoms. Their brain might wake them up several times a night to gasp for air by tightening the throat muscles and opening the airways. Usually the person with sleep apnea does not feel this. Another sign of sleep apnea is being sleepy during the day. The person often sleeps as he or she watches TV or dozes off for a few seconds as he or she drives. In severe cases of sleep apnea, the person may fall asleep at work or during conversations! Another sign of obstructive sleep apnea is that the snoring quiets a little when you turn your body and sleep on your side. That is why doctors ask patients with mild sleep apnea to try sleeping on their side. At times sleep apnea takes the form of going to the bathroom often throughout the night. Patients with sleep apnea may wake up and think they did because they had to go to the bathroom, not realizing that the sleep apnea woke them up. 7

8 Diagnosis Your doctor needs to diagnose whether your symptoms are indeed sleep apnea before recommending any treatment. Severe cases of sleep apnea are easy to diagnose. Milder cases of sleep apnea are more difficult to diagnose. Your doctor will first ask you questions about how you re sleeping and how energetic you are during the day. He or she may want to ask your family and bed partner too; they are usually more aware of your sleep behavior than you are. Your family doctor may want to refer you to a specialist. This is usually a throat doctor, a lung doctor or a nerve doctor. Sometimes he or she may refer you to a sleep center, where you may have to stay overnight so they can observe you as you sleep. This is known as a sleep study. Some medical centers can arrange for the sleep study to be conducted at the patient s home. During a sleep study, advanced medical equipment records what happens to your body as you sleep. The most common record used to find out if you have sleep apnea is called a polysomnogram or PSG. This test records body activity including: Breathing and heart rate Brain and muscle activity Level of oxygen in your blood Eye movement A PSG is painless. You will go to sleep as usual. A sleep medicine specialist will analyze the PSG and determine if you have sleep apnea and how severe it is. A PSG can diagnose sleep apnea accurately. Your doctor may use other simpler tests if your symptoms Polysomnogram are clear. One such medical test is oximetry, which is a test to measure your blood oxygen level. During this test, a simple sleeve fits painlessly over one of your fingers to collect the information while you sleep at home. 8

9 Treatment Options Your doctor can recommend a treatment for sleep apnea that is best for you. This is usually based on your health condition and the severity of your sleep apnea. There are no medications to treat sleep apnea. The treatment of sleep apnea aims at restoring normal breathing during sleep and reducing daytime sleepiness. For mild sleep apnea, doctors usually start by recommending lifestyle changes such as: Avoiding alcohol Avoiding sedatives Losing weight Quitting smoking Sleeping on your side In some cases of sleep apnea, doctors may recommend a mouthpiece to keep the airway open during sleep. A dentist or an orthodontist makes the mouthpiece. The mouthpiece will adjust the lower jaw and tongue to help keep the airway in the throat open. The mouthpiece works for some people with sleep apnea but may, in the long run, damage the teeth, gums and jaw. If lifestyle changes do not help reduce your apnea, doctors usually recommend a treatment called CPAP. CPAP stands for Continuous Positive Airway Pressure (CPAP). The CPAP machine blows air into your nose. This helps keep the airways open! There are different models of CPAP machines, but many have a mask that you put on your nose before you sleep. CPAP has been a very successful treatment for sleep apnea and is now the most common way of treating this medical condition. If you try CPAP therapy, you need to give it 2 weeks or more to work. You need to learn how to put the mask on correctly so it does not put pressure on your face. A healthcare provider will teach you how. The pressure in the CPAP machine can be adjusted to fit your needs. If CPAP Treatment you are having trouble with your CPAP, talk to your sleep medicine specialist or to the person that trained you how to use the CPAP. New models exist that may work better for you. 9

10 In some cases of sleep apnea, doctors recommend surgery to remove excess tissue blocking the airway. For instance, in children with enlarged tonsils and adenoids, surgery could be done to remove the enlarged organs. When all treatment fails to treat severe sleep apnea, doctors may recommend opening a small hole in the throat to allow air to flow through a tube directly to the lungs. This procedure is called tracheostomy. Conclusion In sleep apnea, breathing stops or gets very shallow. The most common type of sleep apnea is obstructive sleep apnea, when muscles and tissues in the throat obstruct airflow to the lungs. If you have sleep apnea, your family members may notice the symptoms before you do. You will probably not be aware that you have problems breathing while asleep. If your bed partner tells you that you have one or more of the following symptoms, see your doctor to check if you have sleep apnea. Snoring loud with shortness of breath Intermittent pauses in your breathing during sleep Sudden loud snorts or gasps for air as you sleep Constant daytime drowsiness Getting treatment for sleep apnea can help you get deep sleep, which will restore your daytime energy. It will also prevent heart diseases, high blood pressure, heart failure, heart attack and stroke. Sleep apnea can be very serious. Diagnosing it and receiving treatment will not only improve your energy and health, it may also improve the sleep and happiness of your loved ones. 10