الفهرس 
Upper airway anatomyOnly 14 pages are availabe for public view
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Abstract
Obstructive sleep apnea is a condition defined by repetitive episodes of cessation or reduction of airflow during sleep, associated with arousals from sleep due to complete obstruction of the upper airway.
Obstructive sleep apnea (OSA) syndrome is a relatively common but fatal disorder affecting 24% percent of healthy middle aged men and 9% of healthy middle aged women have evidence of obstructive sleep apnea. However 4% of the adult male and 2% of female are symptomatic and have the syndrome
The upper air way formed by the nose, mouth, the pharynx and the larynx each of these areas has different pathologies that can produce obstructive sleep apnea syndrome.
Obstructive sleep apnea is a complex disease whose etiology is multifactorial. any condition causing narrowing of the upper respiratory tract may lead to obstructive sleep apnea as nasal turbinate hypertrophy , nasopharyngeal adenoidal hypertrophy , elongated or thickened palate or uvula , macroglossia , laryngomalacia . Functional disorder as hypotonia of pharyngeal muscles by long use of sedatives, alcohol may also cause obstructive apnea during sleep.
Known and suspected predisposing conditions for obstructive sleep apnea
Condition Examples Contribution
Obesity, body fat distribution Adult obesity, Complex and ill-defined
Race/genetics Familiar genetic element
Age ? Tissue laxity
Male gender Unclear
Alcohol sedatives, analgesics, anesthetics Muscle relaxation depressed arousal
Smoking ? Chronic nasal congestion, pharyngeal oedema
Nasal obstruction Septal deviation, chronic nasal congestion Increased Pharyngeal negative pressure
Pharyngeal obstruction Tonsillar and adenoidal hypertrophy Increased Pharyngeal negative pressure
Cranio-facial abnormality Down’s Pierre-Robin, Treacher-Collins, Apert’s, Crouzon’s, Beckwith-Wiedemann, achonDROPlasia, acromegaly, fragile-X Mid-face hypoplasia, macroglossia or micrognathia
Endocrine/Metabolic Hypothyroidism, androgen therapy, Cushing’s Upper airway infiltration or myopathy, obesity
Connective tissue disorder Marfan’s Abnormal upper
Airway connective
Tissue
Neuromascular disorder Poliomyelitis, myotonic dystrophy, dysautonomia, tetraplegia Disordered pharyngeal neuromuscular function
Chronic renal
Failure Unclear
Modern sleep researchers and clinicians analyze sleep using astandardized manual prepared by a committee chaired by Drs. A.Rechtshaffen and A. Kales.
This manual, first published in 1968, describes both recording methods and techniques for describing sleep
The Rechtshaffen and Kales (abbreviated as R & K) system subdivides sleep into two general states: rapid eye movement sleep (REM) and non-rapid eye movement sleep (NREM). NREM sleep is further subdivided into four NREM stages.
REM SLEEP - Rapid eye movement sleep was first described in 1953 when researchers observed periods of relatively fast electroencephalogram (EEG) activity recurring every 90 to 120 minutes
Detection of the sites of upper airway obstruction have been attempted by a variety of techniques including, acoustic reflection (analyzing reflected sound waves from the respiratory system which provides a calculation of the upper airway area, Fluoroscopy (used to study upper airway closure during sleep in patients with sleep apnea) Cephalometry ( a standardized lateral radiograph of the head and neck examining upper airway bony and soft tissue structure ), Rhinometrics (evaluate the nasal passages , oropharynx , and vocal cords) , Pharyngomanometry (catheters positioned in the upper airway can measure pressure differences during an apnea to localize the sites of obstruction) , Computed tomography CT (provides excellent imaging of the airway , soft tissue , and bony structures from the nasopharynx to larynx) , Magnetic resonance imaging MRI (provides excellent upper airway and soft tissue resolution including adipose tissue).
Obstructive sleep apnea (OSA) syndrome can affect the patient during sleep, by restless sleep , night mares , nocturnal enuresis and during day time by morning headache , impaired concentration , hyper-somnolence and this may cause cardiac arrhythmia , pulmonary hypertension , systemic hypertension , heart failure and even sudden death
Treatment aspects of obstructive sleep apnea divided into non surgical aspect (conservative and medical) and surgical aspect.
Conservative treatment include lifestyle modifications by identifying and attempting to correct lifestyle issues,
Weight reduction particularly regional neck obesity is a major risk factor for (OSA), avoidance of alcohol and other respiratory depressants, Smoking cessation as cigarettes smoking is a risk factor for (OSA), Sleep position as the collapsibility of the upper airway during sleep in patient with (OSA) as measured by critical closing pressure is lower in the lateral than in the supine position.
Pharmacological (medical) treatment have been tested, putative mechanisms of action include increased ventilatory drive (eg. acetazolamide), selective activation of upper airway dilator muscles (e.g. strychnine) many of these agents are limited by poor patient tolerance and there use is not supported by randomized controlled trials.
Continuous positive airway pressure (CPAP) oxygen supply improves overall oxygenation during sleep but increases apnea duration while reducing apnea frequency.
Surgical treatment of (OSA) predated the development of CPAP and oral appliances. the aim of surgical treatment is to bypass or remove the site of upper airway obstruction, tracheostomy achieves the goal of bypassing and was utilized as an effective treatment for OSA long before the tracheostomy as the primary treatment for the disease , but disfiguring nature and the attendant long term morbidity of tracheostomy have led to the development of other alternative surgical approaches as , resection of redundant soft tissue ( nasal surgery , uvuloplatopharyngoplasty (UPPP) , laser assisted UPPP and midline glossectomy , induction of scar tissue formation (cautery or radiofrequency ablation of soft palate , tongue or epiglottis) , displacement of bony and ligamentous attachments of upper airway soft tissue structures , maxillary and mandibular osteotomies , tongue and hyoid suspension .
Many combinations of surgical procedures coexist in aim to improve the success rates including; 50%success rate in UPPP and tongue –base radiofrequency, 42-59% in UPPP and midline glossectomy, 33-77% in UPPP and genioglossus advancement with or without hyoid myotomy and suspension. The most impressive results of 90% or more occur with combined UPPP, genioglossus advancement, and maxillary – mandibular advancement.