Treatments of Obstructive Sleep Apnea (OSA)
Elimination of Snoring
Decreasing Morbidity (Incidents of Disease)
Decreasing Mortality (Death)
The aggressiveness of treatment is dependent on the severity of the underlying disease, the desired outcome, and confounding medical conditions. No single treatment is appropriate for all patients and often multiple therapies may be required.
Treatment of Predisposing Factors
Predisposing factors include: positional therapy, weight loss, addressing poor sleep hygiene, treating nasal obstruction, avoiding sedatives and alcohol, increasing exercise, and smoking cessation. Positional maneuvers attempt to keep patients with mild positionally dependent apnea or snoring off their back (where disordered breathing is often worse) or alter head position. A multitude of snore pillows, alarms, or mechanical devices have been offered as positional therapy. Positional therapy can seldom be dependably maintained. Earplugs for bed partners, medical treatment of nasal disease, and nasal dilators may successfully treat mild apnea and snoring complaints.
Treatment of obesity is important in all obstructive sleep apnea patients. Rarely weight loss alone may be curative (less than 3%). Moderate weight loss, nonetheless, may significantly improve OSAS or snoring. In severe apnea, definitive treatment (medical or surgical) is necessary in conjunction with weight loss. Weight Control, as a part of therapy, is important since weight gain is associated with worsening or recurrence of OSAS. Bariatric surgery (surgical weight loss) may be indicated in morbidly obese patients. Since weight loss therapy is not immediately effective, other definitive treatment is still required. Patients with morbid obesity and OSAS are at significant risk of respiratory complications following major abdominal surgery. Long-term results suggest that there may be a reappearance of OSAS. Objective improvement is maintained only in patients that do not regain weight.
Sleep deprivation disrupts sleep architecture. It may increase unstable breathing and apnea, and contribute to daytime hypersomnolence (sleepiness when awake) in mild apnea. Improved sleep hygiene may reduce snoring, apnea, and hypersomnolence. Alcohol and sedatives reduce muscle tone, increase upper airway collapse, and worsen sleep quality. Smoking alters respiratory control during sleep and increases congestion, both of which may worsen OSAS.
Treatment of Underlying Medical Causes
Hypothyroidism, Marfan's Syndrome, acromegaly (chronic disease of adults caused by hypersecretion of the pituitary growth hormone ), and congestive heart failure may contribute or cause obstructive sleep apnea. Adequate thyroid replacement or treatment of acromegaly by ablation (removal) of pituitary adenomas (benign tumors) may be associated with reversal of obstructive sleep apnea. Obstructive apneas and periodic breathing may reverse with treatment of the heart failure. Acute medical or surgical therapy may also be required. Objective follow-up after treatment of medical causes is necessary since obstructive sleep apnea may persist even when underlying medical disease is reversed.
Protryptyline, a non-sedating anti-depressant, increases upper airway muscle tone, reduces rapid eye movement (REM) related apnea by decreasing REM sleep, and acts as mild respiratory stimulant. Symptoms of daytime fatigue may decrease even without lessening of respiratory disturbance index (RDI). The side effects limit Protryptyline's use. Oxygen therapy may diminish severity of oxygen desaturation but may potentially lengthen apnea duration in selected patients. Pharmacologic agents are not generally used as single treatments for OSAS.
Nasal continuous positive airway pressure (CPAP) applies positive pressure to the upper airway and effectively acts like a pneumatic (air or respiratory) splint to maintain airway patency (openness). Physiologically, nasal CPAP increases intraluminal pressure to keep airway pressures above collapsing pressures during both inspiration (act of drawing air into the lungs) and expiration (act of expelling air from the lungs). Due to negative inspiratory pressures, nasal continuous positive airway pressures need to be greater during inspiration than during expiration. Nasal CPAP also increases lung volume, which may improve oxygenation.
Effective nasal CPAP pressure to treat OSAS varies depending on sleep state, body weight, head and body position, nasal patency, and sedative use. CPAP pressure must be individually titrated (determine the amount to be used for a given result) and may need periodic adjustments if signs of symptoms warrant. Incorrect pressure settings may under-treat apnea resulting in arousal and movement, which may dislodge the device. Alternately, too high pressure increases spontaneous arousal, central apnea, and patient intolerance.
Nasal CPAP objectively reduces the respiratory disturbance associated with OSAS. Successful use of CPAP reduces symptoms of excessive daytime sleepiness, and the long term sequela (condition resulting from a previous disease) and increased deaths associated with OSAS. However, even a single night without the use of nasal CPAP will result in recurrence of many of the symptoms and daytime sleepiness of OSAS.
The reasons for failure vary but successful nasal CPAP requires: 1) a correct machine pressure setting, 2) a comfortable and air tight patient/mask interface, 3) patient tolerance, and 4) patient compliance.
Poor patient mask interface may result in face or mouth air leaks. High air flow is often intolerable and also results in loss of effectiveness. Chin straps, nasal prongs, better fitting face masks may decreases air leaks. Other factors influencing patient tolerance and compliance include lifestyle, mask claustrophobia, rhinitis, nasal obstruction, and the level of positive pressure.
Clinical effectiveness requires nightly use. Verbal reports of compliance range from 50-70 percent. Objective studies demonstrate lower compliance rates. Although 70 percent of patients utilize CPAP for 20 minutes on 70% (5-7) of nights, only 50% of patients use CPAP for four hours a night. Use of nasal CPAP is associated with low risks of serious complications. Most problems with nasal CPAP relate to rhinitis, mask discomfort, claustrophobia, Eustachian tube dysfunction, and noise. Patient compliance may be higher in patients with more severe disability. Compliance patterns with CPAP are established early in the course of treatment and may be improved by regular encouragement by the physician. The pattern of use as early as three weeks has been correlated to subsequent compliance.
A variety of CPAP machines have been developed to minimize patient intolerance. For example, patients who have difficulty initiating sleep on nasal CPAP can utilize "ramped" CPAP devices which gradually increase applied pressure so that maximum pressure is achieved after sleep onset. Advances and applied pressure may include "smart machines" that self titrate the pressure to the patient. Warm or cool humidity may help improve comfort and reduce nasal symptoms.
In many patients, high expiratory pressures are not tolerated. Nasal bilevel applied pressure devices apply different inspiratory and expiratory pressure. These pressures can be varied independently in any given patient. In theory, lower applied expiratory pressures may maintain airway patency and may improve the patient tolerance. In patients with a greater than six (6) cm H2O difference in inspiratory and expiratory pressures, bilevel pressure devices are used better than nasal CPAP. Bilevel pressure may also assist and improve ventilation in some patients by applying higher expiratory than expiratory pressures. Although helpful in many patients with CPAP complications, objective studies have not demonstrated improved compliance compared to traditional nasal CPAP when it is applied to all patients.
Oral appliances may be either mandibular repositioning devices or tongue retaining devices. A significant reduction in respiratory disturbance index (RDI) occurs with use of oral appliances especially when apnea is mild (RDI<40 events/hour) and in less obese subjects. Individual clinical responses are variable. Sixty to 80% of patients will note a decrease in snoring. Many patients report discomfort of teeth, gums, and temporo-mandibular joint complaints following prolonged use. Patient compliance is required for successful therapy.
A surgical approach to treat OSAS is indicated in patients with (1) overt pathological lesions of the upper airway, (2) apnea that has failed medical treatment, (3) a lifestyle that precludes other treatments, and (4) habitual snoring in the absence of OSA. Multiple procedures have been proposed to treat OSAS. Selection of these procedures for elective surgery is based on (1) the location of the collapse, (2) the severity of disease, (3) associated medical risk, (4) morbidity of treatment, and (5) likelihood of surgical success. Since multiple differing segments may require modification, no single surgical approach is applicable for all patients.
Surgery may (1) bypass the upper airway via tracheotomy or (2) modify the upper airway using soft tissue or skeletal techniques to prevent collapse and obstruction. Modifications of the upper airway may be accomplished by directly altering soft tissue adjacent to the airway or indirectly by advancing the supporting skeletal structures that support these soft tissue structures. All procedures attempt to stabilize the airway during sleep by altering airway size, shape, or collapsibility.