Sleep – Disordered Breathing
Sleep Apnea Syndrome (SAS)Professor Adnan Mohammed Al-Jubouri
M.B.CH.B (Baghdad)
M.R.C.P. (U.K.)F.R.C.P. (Edin.)
A variety of respiratory disorders manifest themselves during Sleep, for example : nocturnal cough & wheezes (clinical features of Asthma) & hypoventilation (that occurs in normal sleep can exacerbate Respiratory Failure in patients with Restrictive Lung Diseases like : kyphoscoilosis, diaphragmatic palsy, & muscle weakness, or in patients with Intrinsic Lung Diseases like : COPD & pulmonary fibrosis).
In contrast, a small but important group of disorders can cause problems only during sleep.
Sleep – Disordered Breathing
* There is a recurrent upper airways obstruction during sleep, & the mild form of this syndrome is the “Snoring”.
As we know, the “Throat” is the upper airway opening, if we take a deep breath, a negative pressure will be created, & since there is soft tissues in the throat, it tends to collapse because of this negative pressure; but because of the presence of the upper airways dilating muscles (which are : Palatoglossus & Genioglossus), they tend to tense themselves & so keeping the throat opened.
Sleep Apnea Syndrome (SAS)
So, if there is a slight narrowing of this opening, snoring will develops (snoring is present in 40% of males & 20% of females). & if the narrowing is so severe, occlusion or near occlusion of the upper airways opening, no air will get in, & this will stimulate the respiratory center due to hypoxia & hypercapnia, & this will send a signal to the respiratory muscles to perform more work, this will awake the patient, then the patient sleeps, leading to “Apnea”, & again awake the patient. This condition is repeated many times during sleep, so the patient will not get enough sleep, with the tendency to develop HTN, IHD, & Stroke.
Causes of SAS :
1- Familial causes (especially in males).2- Obesity*, because of more fatty tissue causing smaller opening of the upper airways.3- Patients with Acromegally.4- Patients with Hypothyroidism.5- Alcoholic patients.6- Patients taken Sedative Drugs.
*Obesity, is one of the important predisposing factors for this
syndrome, & the tendency of obesity is increased nowadays in
the community, & in a report (from another country) that about
(2 – 4 %) of the population are having SAS.
Clinical Features of SAS :
1- Excessive day-time sleepiness is the principle symptom.2- Snoring is virtually universal.
3- The patient usually feels that he/she has been asleep at night but wakes un-refreshed.
4- Lack of concentration*.
5- He will have impaired cognitive function & work performance.
6- Also, he will have Depression, Irritability, & Nocturia.
* So, those patients are largely involved in Road Traffic Accidents.
Differential Diagnosis of SAS :
We should exclude some conditions by a careful history.Narcolepsy is rare cause of sleepiness, & it is account for only 0.05%.
There is other associated illnesses like : Cataplexy*, Hypnagogic Hallucination (occurs at sleep onset), & Sleep Paralysis.
Also, Idiopathic Hyper-somnolence which occurs in young individuals, & it is characterized by long nocturnal sleep.
*Cataplexy : happens when the muscle tone is lost in a very
conscious person in response to emotional triggers
& they may flap over.
Treatment of SAS :
It is usually directed to the Cause :
- Obesity, reduce the weight.
- Treat acromegally & hypothyroidism.
- Stop alcohol & sedative drugs intake.
But, the proper treatment is by using a Specific Nasal Mask that keeps a continuous positive pressure in the throat, so no negative pressure will cause no more collapse & sleep becomes normal.
*This mask is termed as C-PAP = Continuous Positive Airways
Pressure devices.