There may then be a period of apnea, where breathing briefly ceases, before the cycle begins again.
On average, each cycle lasts between 30 seconds and 2 minutes.
This respiratory condition occurs both during sleep and wakefulness, although it is believed to be more common during sleep.
While Cheyne-Stokes respiration usually occurs during slee, it may also happen during waking hours.
People with Cheyne-Stokes respiration usually experience:
- Orthopnea: This is shortness of breath when lying down.
- Paroxysmal nocturnal dyspnea: Severe shortness of breath and coughing fits. These usually occur at night, and disrupt sleep.
- Excessive daytime sleepiness and fatigue: This is caused by periods of interrupted sleep.
How does it happen?
The physiological processes that lead to the development of Cheyne-Stokes respiration, which involves the cardiovascular, pulmonary, and sympathetic nervous systems, are not fully understood.
However, it is thought to be linked to:
- Unstable feedback in the respiratory control system. Changing levels of oxygen and carbon dioxide in the blood cause the cycles of apnea and hyperventilation.
- Delayed circulation. Circulation time is increased in people with congestive heart failure and Cheyne-Stokes respiration. This is not considered a significant contributor to the cause of the condition, but it is directly related to the length of the abnormal breathing cycles.
Another potential cause is reduced blood gas buffering capacity. The bicarbonate buffer system helps maintain the pH of the body by expelling carbon dioxide through exhalation.
As those with Cheyne-Stokes respiration hyperventilate, their total carbon dioxide stores are likely to be reduced, which interferes with the carbon dioxide buffering capacity of the body.
Low levels of oxygen in the body may also intensify blood gas fluctuations in those with Cheyne-Stokes respiration.
Who is at risk of Cheyne-Stokes respiration?
Cheyne-Stokes respiration can occur in people with neurological conditions, or congestive heart failure. Some research estimates that 50 percent of all people who have moderate to severe congestive heart failure also have significant Cheyne-Stokes respiration.
The condition is also recognized as a component of the sleep apnea syndrome.
However, many cases of Cheyne-Stokes may remain unrecognized, particularly as it is most common during sleep.
Cheyne-Stokes is usually associated with heart failure or stroke, but it is also linked to several other conditions including:
Cheyne-Stokes respiration is commonly linked to heart failure or stroke.
- altitude sickness
- brain injury
- brain tumors
- carbon monoxide poisoning
- chronic pulmonary edema
- intercranial pressure
- kidney failure
- toxic encephalopathy
Cheyne-Stokes respiration may also be seen in those who are dying, as the body attempts to deal with changing levels of carbon dioxide.
The major risk factors for Cheyne-Stokes respiration are heart failure and stroke, although development of any of the conditions associated with Cheyne-Stokes can be considered a risk factor.
Other abnormal patterns of respiration
This condition is also characterized by deep, rapid breathing. However, Kussmaul breathing does not feature the shallow breaths, apnea, or alternations in breathing patterns experienced in Cheyne-Stokes respiration. It remains deep and rapid throughout.
Kussmaul respiration can be seen in people with diabetic ketoacidosis or kidney failure. It is a compensatory measure to try and regain a balance between acid and alkaline in the body, as the body tries to rapidly exhale carbon dioxide, which is acidic.
Also known as Biot's respirations, cluster breathing is characterized by groups, or clusters, of rapid, shallow breathing. This is followed by periods of apnea. It differs from Cheyne-Stokes respiration in that it does not feature cycles of deep breathing, or gradual alternations in breathing patterns.
Characterized by over-breathing, where breathing is deep and rapid, hyperventilation causes low levels of carbon dioxide and high levels of oxygen in the blood.
People who are anxious, stressed, or experiencing a panic attack may hyperventilate. Symptoms include dizziness, weakness, fainting, and confusion.
Breathing that is too slow or too shallow is called hypoventilation. It causes high levels of carbon dioxide and low levels of oxygen in the blood.
Obstructive sleep apnea
People with obstructive sleep apnea experience momentary periods where breathing stops during sleep. These periods of apnea are caused by upper airway collapse, and may occur over five times each hour.
Obstructive sleep apnea is linked to obesity. Symptoms include headaches upon waking, difficulty concentrating, and daytime sleepiness.
Diagnosing Cheyne-Stokes respiration can be difficult as it most commonly occurs during sleep.
Those who are experiencing the symptoms of Cheyne-Stokes or other abnormal breathing patterns should consult a doctor, who may make a diagnosis based on symptoms and a physical examination.
If the condition occurs at night, a doctor may recommend a polysomnography, which is a type of sleep study. This type of study is carried out at a hospital or sleep center. It records heart rate, breathing rate, brain waves, blood oxygen levels, eye movements, and other movements during sleep.
Management of Cheyne-Stokes respiration may include some or all of the following treatment options.
Heart failure treatment
Treating the underlying congestive heart failure may help alleviate symptoms of Cheyne-Stokes respiration.
Treatments may include:
- cardiac valve surgery
- heart transplant
- pacemakers and other devices
Several studies suggest that short-term oxygen treatment during sleep can reduce Cheyne-Stokes respiration.
Night oxygen therapy has been found to improve a person's symptoms, their quality of life, and the function of the left ventricle, which is one of the chambers of the heart.
Continuous positive airway pressure (CPAP)
CPAP masks are a common method used to treat sleep apnea.
Continuous positive airway pressure is the leading treatment for sleep apnea. This therapy uses mild air pressure to keep the airways open. The individual wears a mask over their mouth, nose, or both. The mask is connected by a tube to a CPAP machine that supplies the tube with a positive flow of air.
Observable benefits include better sleep quality, reduced snoring, and less daytime sleepiness. Long-term benefits include blood pressure control, reduced risk of stroke, and improved memory.
However, some research indicates that CPAP does not increase survival rates in people with heart failure, although other research suggests that 43 percent of people experience beneficial effects in terms of their Cheyne-Stokes symptoms.
According to the National Sleep Foundation, most insurance companies will cover CPAP treatment.
Preventing Cheyne-Stokes respiration involves preventing the medical conditions that are associated with it, including heart failure and stroke.
People with these conditions should ensure they follow their treatment plan to help manage their symptoms, which may help prevent Cheyne-Stokes respiration.
Avoiding exposure to heavy metals and other toxins, which can cause toxic encephalopathy, will also help prevent the condition.
Cheyne-Stokes respiration is a serious condition. As it often develops in people with severe heart failure, or in end of life care, it can be considered a poor sign. However, this is not always the case, and it may be found in otherwise healthy people with altitude sickness, or during sleep.
In some research, patients with congestive heart failure and Cheyne-Stokes respiration were found to have a higher rate of mortality, especially if they experienced the breathing difficulties during their waking hours. This happens because Cheyne-Stokes respiration places further stress on a failing heart.