Please check my essay for the grammar mistakes, for the length of the sentences, and for the correct MLA citation. Thank you.
Introducing sleep apnea, the silent killer.
Even if its history goes back to the ancient times, sleep apnea is a newly acknowledged and still underdiagnosed sleep disorder. Besides the first records of its symptoms, such as heavy snoring, dating back over two thousand years, the scientists of the modern world waited until 1870s to report the first several cases of obstructed apneas. Unfortunately, these cases accurately described by British physicians as "fruitless contractions of the inspiratory and expiratory muscles against glottic obstruction with accompanying cyanosis during sleep" (Dempsey, Veasey, Morgan, O'Donnell), went unnoticed and for the next one hundred years sleep apnea existed under the term of 'Pickwickian syndrome' after Charles Dicken's Fat Boy Joe, an obese persons with extreme daytime sleepiness and other apneic symptoms, described by the author in his Pickwick Papers from 1837. During that time sleep apnea was solely blamed on patient's obesity rather than on disordered breathing and obstruction in upper airways during sleep. The break in the research came in 1965, when the first polysomnograph recorded apneas during sleep, and Dr. William Dement established the first sleep clinic at Stanford University, California. Together with Christian Guilleminault and other scientists, Dr. Dement started an extensive research concentrating on respiratory disorders during sleep, and providing first comprehensive links between obesity, sleep-induced airway obstruction, sleep fragmentation, and daytime sleepiness (Dempsey, Veasey, Morgan, O'Donnell). These findings triggered an extensive sleep apnea research contributing to the growth of sleep medicine as an independent and important specialty in the medical field.
But even if there has been an explosion of basic, clinical, and population research directed toward the prevalence, causes, consequences, and treatment of this problem, there is not enough recognition and awareness of sleep apnea between patients, and what's more important, between the health care professionals. Considering (the seriousness) the magnitude of the problem, and the negative impact it has on human health, our society should not only be better educated about the physiology, risk factors, symptoms, and harmful effects of sleep apnea, but should also know how to diagnose and treat that disorder (but should also know the best diagnostic and treatment methods).
The physiology of sleep apnea can be explained by combining the word sleep with translation of word "apnea", which in Greek means "without breath". "Sleep without breath" accurately describes that chronic disorder, in which breathing is briefly and repeatedly interrupted during sleep. Those interruptions can last from 10 seconds to minutes and may occur 30 times or more an hour (Brooks, Lee-Chiong, Mattice, 2012.) Based on American Association of Sleep Medicine's guidelines less than 15 apneas an hour indicates mild case of a sleep apnea, between 15 and 30 moderate, and more than 30 apneas an hour is an indicator of a severe case of that disorder. Another criterion of severity of sleep apnea is the amount of time that patient's oxygen level drops below 88% of saturation in the blood. A survey done by the Mercy Gilbert Sleep Center, showed that more than 5% of their patients had above 150 apneas an hour, and the longest apnea witnessed in that center lasted more than 2 minutes with an oxygen saturation oscillating between 60% to 70%, which was extremely dangerous to the patient's safety.
Based on a different physiological mechanism, sleep-disordered breathing is divided into "central" apneas, caused by a lack of respiratory drive from a medulla in the brainstem and phrenic nerves, "obstructive" apneas, which are comprised of respiratory efforts against a closed upper airway, and "mixed" apneas, a combination of both - central and obstructive events. Central apneas are rare and consists of 40% of apneas that develop following a cerebrovascular accident. They also accompany disorders like thyroid dysfunction, cerebrovascular disease, acromegaly, renal failure, and CHF between many others. In addition, central apneas occur in 30% of patients undergoing methadone maintenance treatment (Brooks, Lee-Chiong, Mattice, 2012). The obstructive sleep apnea (OSA) being still considerably underdiagnosed, is the most common, and causes the most damage to patient's health (within our society). In most cases OSA is caused by collapsing of the tissue in the back of the throat, relaxation of the muscles in the upper airway, and falling back tongue during sleep. All these phenomena narrow the upper airway, reducing an amount of air that can reach lungs, causing loud snoring and a drop in the blood oxygen level. Deficit of the oxygen in the blood triggers brain arousal, which signals breathing to resume, stimulates the tightening of the muscles and opening of the upper airway. A process which is very often accompanied by a loud snort or a choking sound. This mechanism may happen a few times a night, or in more severe cases, several hundred times a night. Thus, the patient's sleep is extremely fragmented and of poor quality, which is an underlying cause of many serious health problems.
Unfortunately, in most cases the sleeper is unaware of these breath stoppages because they don't trigger a full awakening. While awake, people affected by sleep apnea are capable of precise regulation of their ventilation and experience little or no problems with their breathing, which is one of the reasons why this sleep disorder is usually so hard to discover, and most sufferers go undiagnosed (Dempsey, Veasey, Morgan, O'Donnell). The other reason is lack of recognition of the most important sleep apnea risk factors. Per the National Sleep Foundation there are multiple and often intertwined risk factors that predispose for OSA. This sleep disorder can affect more than 18 million Americans, and can strike anyone at any age, even children, especially with enlarged tonsil and adenoids. Based on the results of NSF's research male after 40 are two times more at risk than female the same age, particularly African-American and Hispanic men, and the probability of developing sleep apnea increases with age, especially for people with family history of that disorder. According to the Mayo Clinic people with weight problems and thick neck tend to have fat deposits around their upper airway, which may obstruct breathing. Naturally narrow airway, shape of the face and skull, deviated septum and other issues that make it tough to breathe through the nose may also increase the risk of sleep apnea. Because smoking causes inflammation and fluid retention in the upper airway, smokers are three times more likely to have obstructive sleep apnea than people who've never smoked, and frequent use of muscle relaxing substances like alcohol, sedatives and tranquilizers also enhances the chance to acquire that sleep disorder.
In addition to all those risk factors, there are also telltale symptoms and warning signs, which might help to discover and diagnose sleep apnea. One of the first, and very characteristic sign is a loud persistent snoring. Not all people who snore have sleep apnea, but if snoring is accompanied by restless sleep, witnessed pauses in breathing, choking, or gasping for air during sleep, there is a big probability of the existence of that sleep disorder, especially when those symptoms are followed by extreme fatigue, poor concentration and sleepiness during the day. The other warning signs, which should not be ignored are difficulty falling or staying asleep, gastric disturbance, excessive sweating, sexual dysfunction and frequent visits to the bathroom during the night. There are also less obvious but equally important daytime symptoms like early morning headaches, daytime gastric reflux, irritability, depression, forgetfulness and impatience (Brooks, Lee-Chiong, Mattice, 2012). Even if these symptoms do not look very threatening, and usually are mistakenly blamed on stress and fast paced everyday living (life), they should be discussed with a primary doctor and consulted with a sleep specialist, to rule out sleep apnea or other sleep disorders. Because if they really are results of sleep apnea, the combination of disturbed sleep and oxygen starvation may lead to serious health problems, and put people's safety and well-being at risk.
The first noticeable negative effect of sleep apnea is sleep deprivation caused by difficulty falling or staying asleep, and fragmented, restless sleep. The consequence of sleep deprivation is reduced ability to learn and to utilize memory. Regular good night's sleep should consist of four different sleep stages, and two of them, deep sleep and rapid eye movement sleep (REM) which follows the first lighter stages, play a crucial role in the consolidation of memory essential for learning new information. Frequent arousals and impossibility to reach deeper sleep stages, not only reduce one's ability to learn, but a sleep-deprived person cannot focus attention optimally and therefore cannot learn efficiently in the first place. Additionally, an insufficient sleep impairs people's work performance by affecting their mood, motivation, and perception of events.
Another negative result of sleep deprivation is an excessive daytime sleepiness, which combined with impaired judgment and inability to make sound decisions can lead to an increase in errors at the workplace, and accidents that cost both lives and resources. Great examples of making incorrect decisions while operating under extreme sleep deprivation are 1979 nuclear accident at Three Mile Island, 1986 nuclear meltdown at Chernobyl, the grounding of the Exxon Valdez oil tanker, and the explosion of the space shuttle Challenger. Investigations performed after these accidents have ruled that sleep deprivation played a critical role in all of them (Brooks, Lee-Chiong, Mattice, 2012). Also, the excessive sleepiness and drowsy driving are responsible for fully 20 percent of all motor vehicle crashes, and a major cause of truck accidents in the USA. In addition, based on the data from the Institute of Medicine, many preventable medical errors are correlated with a lack of sleep, especially between newly graduated interns working extensive hours with no opportunity for a good-night rest.
Additionally, every arousal caused by cessation in breathing triggers a sympathetic division in the nervous system, which has a stimulant effect and is responsible for the "flight and fight" response. It means that every time patient wakes up because of the low level of oxygen in the blood, sympathetic system tries to help by producing increased heart rate, increased respiratory rate, increased blood pressure, and by adding extra adrenaline and sugar to the blood (Connoly, Guilleminault, Winkle, 1983). In case of moderate and severe sleep apnea, when patient has more than 30 arousals on hour all that extra "help" has a catastrophic impact on patient's health. Based on a Sleep Heart Health Study 50% of patients with mild OSA suffer from hypertension and "there is a linear relationship between increasing AHI (apnea/hypopnea index) and incidence of hypertension", which puts patients with severe cases of sleep apnea at 67% (Lind, Nieto, Young, 2000). Frequent changes in blood pressure cause not only common for OSA patients' arrhythmias, AV blocks, sinus pauses and premature ventricular contractions but also life threatening congestive heart failure, myocardial infarction and sudden cardiac death.
Adding to the list of catastrophic consequences of sleep apnea, researchers from Section of Pulmonary and Critical Care Medicine, Yale Center for Sleep Medicine after conducting the observational cohort study, proved that the obstructive sleep apnea syndrome significantly increases the risk of stroke or death, independently of other risk factors like hypertension. Sleep fragmentation and oxygen deprivation may also lead to type 2 diabetes by adding that extra sugar to the blood stream and by influencing the way the body secretes insulin, a hormone that regulates glucose processing and promotes fat storage. Also, the insufficient sleep and low blood saturation has been linked to increased inflammation, obesity, inhibited growth in children, and many other health issues including depression, anxiety, and mental distress (Brooks, Lee-Chiong, Mattice, 2012).
Fortunately, even if sleep medicine is still new in the medical field, last decades of an intense sleep apnea research, unveiled reliable ways to diagnose and to treat that sleep disorder. The only problem and the main key to the success for its diagnostics and the treatments is patient's participation, which is hard to achieve because of lack of the sleep apnea education and awareness. The National Heart and Lung Institute estimates that 40 million Americans suffer from sleep disorders, very often not even realizing. First, because until recent years' sleep medicine was not recognized as a separate field in the health science, and doctors, who were not following the newest trends in medicine, haven't taken patient's sleep habits under consideration while assessing their condition. Second because insurance companies still refuse to grant reimbursement for sleep diagnostics and treatment, and third and most important treason, because patients don't know how to recognize the symptoms and warning signs of obstructive sleep apnea. As soon as the symptoms are recognized, the primary doctor recommends a consult with the sleep specialist, who evaluates the symptoms, patient's medical and mental condition, family history, use of medication and substance abuse, and examines patient's sleep patterns. Based on the results of that evaluation, physician orders one of the sleep tests, to determine the severity of patient's disorder and to choose the right treatment.
If there is the likelihood of OSA in the absence of comorbidities like moderate to severe pulmonary disease, CHF, or neuromuscular disease, and patient does not have any history of motor vehicle accidents caused by excessive daytime sleepiness, the physician orders limited channel, portable home sleep test (HST- test that can be done at home or in other settings outside the sleep lab). HST usually monitors the amount of oxygen in blood, air movement through the patient's nose and patient's chest movements to check if patient is trying to breath. This monitoring goes throughout the night, but because the brain waves are not monitored during that time, the total sleep time is just estimated. That can produce false-negative results, lowering the amount of apnea events. The results of that tests go to the sleep centers where sleep specialists evaluate them to decide on the best treatment. Very often, based on home test's results patients are sent to the sleep lab for a further evaluation by full PSG (Polysomnography) study (Anderson, Boehlecke, Collop, 2007).
All patients with comorbidities, obesity (BMI > 35), history of falling asleep while driving, excessive daytime sleepiness, diabetes and with other medical conditions connected to OSA are always ordered to have a full overnight sleep test (PSG study) in the certified sleep center. During that study, surface electrodes attached to patient's scalp, face and arms (or legs) record electrical signals generated by patient's brain (to monitor sleep stages), and muscle activity (to monitor body movement); belts placed around patient's chest and abdomen measure breathing effort; and a bandage-like oximeter probe on patient's finger shows the amount of oxygen in the blood. There are also two cannulas - like devices attached to the patient's nose, to monitor air flow through the nose and mouth. All these devices are connected to the measuring equipment, where they are recorded digitally. Patients and all the equipment are monitored by sleep technologists throughout the night, and if the case of a severe sleep apnea is observed during the first few hours of the study, technologists are ordered to start CPAP (continuous positive airway pressure) therapy to help affected patient with breathing. Otherwise, after test is done the certified sleep physician discusses the test results and treatment options with patients (Brooks, Lee-Chiong, Mattice, 2012).
For patients with mild sleep apnea physicians can recommend a behavioral treatment, which consist in lifestyle changes, such as losing weight, changing sleep positions to improve breathing, avoiding alcohol and sleeping pills. For smoking patients suffering from OSA, doctor may also recommend stopping smoking, because it increases the swelling in the upper airway, worsening both snoring and apnea. For the patients with moderate or severe sleep apneas CPAP therapy is always the first recommended choice. CPAP delivers a flow of pressurized air (which acts as a splint) to keep the airway open for consistent breathing and oxygenation. The air is delivered through the mask covering patient's nose (nasal mask), or nose and mouth (full face mask). The mask is attached to the CPAP machine via long tube to allow patient's movement during the night. For patients with many comorbidities, especially with cardiovascular diseases, or pulmonary problems there are more specialized PAP machines like Bi level PAP, for patients with difficulties to control exhalation against the pressure, or ASV (auto servo ventilators) for patients with mixed apneas, between many other PAP machines (Morgenstern, 2016).
And for people who do not like, or cannot tolerate CPAPs, there are also other treatment options. The most popular alternative treatments are dental devices, specifically designed by dentists to help keep the airway open during sleep. Unfortunately, the oral appliance therapy works only for a small percentage of patients, and cannot be used to treat severe sleep apnea. It is also not suitable for patients with comorbidities like pulmonary hypertension. Patients who have deviated nasal septum, enlarged tonsils, or a small lower jaw with an overbite causing the throat to be too narrow, may benefit from a surgical correction (Brooks, Lee-Chiong, Mattice, 2012).
"The most commonly performed types of surgery for sleep apnea include: nasal surgery-correction of nasal problems such as a deviated septum; uvulopalatopharyngoplasty (UPPP)- procedure that removes soft tissue on the back of the throat and palate, increasing the width of the airway at the opening of throat; mandibular maxillar advancement (MMA) surgery- performed to correct certain facial problems, or throat obstructions that contribute to sleep apnea; and tracheotomy the operation which should be considered only if other options do not exist, have failed, are refused or when this operation is deemed necessary by clinical urgency" (Aurora, Casey, Kristo, 2010).
With the explosion of sleep apnea research, and a steady grow of Sleep Medicine, which is establishing a strong position in the medical field, there are also many attempts to find an easier and more comfortable way of helping patients with sleep apnea, than CPAP treatment. The newest device a hypoglossal pacemaker discovered by scientists from Harvard Medical School, works by pacing of the hypoglossal nerve in the neck during sleep, which causes the tongue muscle to stiffen and resist airway closure, thus preventing apnea. This method is a big hope for people with moderate to severe obstructive sleep apnea.
But even if these newest devices will substitute PAP therapies, and will be a solution for those, who did not have other options but a tracheotomy to survive sleep apnea, these newest discoveries will not cure patients, who are not aware of their sickness. Our society should know of sleep apnea, other sleep disorders, and how important a good night's sleep is to maintain mental and physical health. Everybody should be able to recognize sleep apnea's early symptoms, warning signs, and understand ways to diagnose and to treat it. People in the high-risk group should be routinely screened for that disorder, and the health care providers and insurance companies, should understand, that recognizing sleep apnea as a foundation of many health problems and addressing them, even before patients get really sick, will benefit these patients, as well as will bring long term savings in costs for their treatments. Otherwise even the miraculous devices will not be able to protect our population from that silent killer.
Works Cited
Aurora, R. N., Casey, K. R., Kristo, D., 2010. Practice parameters for the surgical modifications of the upper airway for obstructive sleep apnea in adults.
Collop, N.A., Anderson, W.M., Boehlecke, B., Portable Monitoring Task Force of the American Academy of Sleep Medicine. 2007. Clinical Guidelines for the use of unattended portable monitors in the diagnosis of obstructive sleep apnea in adult patients. Journal of Clinical Sleep Medicine
Guilleminault, C., Connoly, S. J., & Winkle, R. A. 1983. Cardiac arrhythmia and conduction disturbances during sleep in 400 patients with sleep apnea syndrome. American Journal of Cardiology
Mattice, Cynthia, Rita Brooks, and Teofilo L. Lee-Chiong. Fundamentals of Sleep Technology. Philadelphia: Wolters Kluwer/Lippincott Williams & Wilkins Health
Michael Morgenstern, M.D. "What is CPAP?"
National Heart, Lung, and Blood Institute online. What are sleep studies.
Nieto, F. J., Young, T. B., Lind, B.K., 2000. Association of sleep disorder breathing, sleep apnea, and hypertension in large community-based study. The Journal of the American Medical Association
Yaggi H.K., Concato J., Kernan W.N., Lichtman J.H., Brass L.M., Mohsenin V. "Obstructive sleep apnea as a risk factor for stroke and death".
"Pace to Breath - New Treatments for Sleep Apnea." Harvard Health Blog.