Central Sleep Apnea. v Characteristics

Transcription

1 Central Sleep Apnea v Characteristics Respiratory pauses > 10 sec Due to failure of brain s respiratory center to send signal to respiratory muscles Tends to occur in infants (neurological immaturity) or elderly (stroke, neurodegenerative disorder) 1

2 Obstructive Sleep Apnea v 1-4% of population v Pickwick Papers (1837) v Osler (1906) v Guilleminault (1973) - OSAS 2

3 Obstructive Sleep Apnea (OSA) v Characteristics Respiratory pauses > 10 sec (usually longer) Due to upper airway blockage that prevents passage of air Most common form; tends to occur in middle- aged males who are obese or who have physiologically narrow airways 3

4 Symptoms of OSA v Snoring Loud snoring usually worse when sleeping on back or after alcohol use; breathing pattern may demonstrate periods of silence broken by snorting or gasping v Obesity Body Mass Index > 35 and collar size > 16.5 in correlate with OSA v Daytime sleepiness May report falling asleep at work, while driving, or during sedentary activities 4

5 Associated Symptoms v Mood changes, memory problems, decreased sex drive, nighttime sweating, increased urination at night, heartburn, waking with a dry mouth v Patient may have micrognathia, retrognathia, large tongue, enlarged uvula, crowded airway, difficulty breathing through nostrils v Important to interview bed partner to obtain full symptom picture 5

6 History v Snoring* v Excessive daytime sleepiness* v Restless sleep v Personality changes v Headaches v Sexual dysfunction v Job performance v Sleep hygiene v Bed partner s input * 6

7 Pathophysiology v Pharyngeal collapse v Decreased airway patency v Increase in negative pressure v Becomes a vicious cycle 7

8 v Anatomic narrowing Pathophysiology Requires increased inspiratory pressures v Abnormal neuromuscular control Reflex activation of dilators in response to airway obstruction often fails 8

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10 Diagnosis of OSA v Apnea Complete cessation of breathing > 10 sec v Hypopnea Partial reduction of airflow by > 30% v Oxygen desaturation Oxygen desaturation > 4% from sleep baseline 10

11 Diagnosis of OSA (con t) v Apnea-Hypopnea Index (AHI) Total number of apneas and hypopneas divided by number of hours slept o o o Mild OSA: AHI = 5 14 events per hour Moderate OSA: AHI = events per hour Severe OSA: AHI = 30+ events per hour v Also considered in diagnosis are: Number and severity of oxygen desaturation episodes Number of awakenings Severity of daytime symptoms 11

12 Normal Vs. Disordered Breathing v A few brief respiratory pauses are normal: During transition from wakefulness to sleep During REM sleep when there is a profound loss of muscle tone v OSA is progressive: 1. Intermittent snoring and mild breathing problems 2. Snoring and mild to moderate respiratory pauses 3. Long respiratory pauses, severe drops in oxygen, many arousals during sleep 12

13 Epidemiology of OSA v Prevalence of OSA: 2-9% of women (more frequent postmenopausally) 4-24% of men 32% of men and 19% of women snore nightly v OSA is associated with cardiovascular disorders Hypertension, stroke v Risk factors: Smoking, alcohol use, poor eating habits/obesity 13

14 Epidemiology of OSA (con t) v Social impact: Reduced work productivity Increased rate of automobile accidents Marital stress v Typical presentation: Obese, middle-aged males BUT, OSA can occur in either gender, any age, and any body type 14

15 APNEAS Ì Í Ó HYPOXEMIA Í SLEEP Ó Ó Í DISRUPTION Ó Í Ì Ì Ó DAYTIME Ì SOMNOLENCE Ì Ó Í COGNITIVE Ì DEFICITS 15

16 NATURE OF COGNITIVE DEFICITS  General intellectual functioning  Attention/Vigilance  Memory  Executive function  Manual dexterity 16

17 NOCTURNAL SLEEP IN OSAS CONTROLS BASELINE APNEICS A B Sleep % Wakening 10.7 (6.1) 12.7 (9.4) % Stage (3.6) 33.4 (21.7) % Stage (6.4) 54.0 (20.8) % SWS 10.6 (5.8) 2.5 (3.1) % REM 15.2 (5.9) 9.9 (3.4) Nb of awakenings 33.7 (11.1) 75.7 (55.0) Nb of stage shifts (34.7) (222.3) From Bédard,et al. Sleep

18 COGNITIVE DEFICITS IN OSAS CONTROLS BASELINE A B General functioning Full Scale IQ (8.1) (8.9) Verbal IQ (9.2) (9.9) Performance IQ (7.4) (7.9) Attention Digit Symbol 8.5 (2.1) 7.2 (1.2) Letter Cancellation 1.1 (0.6) 4.0 (3.2) Memory Rey fig. (Imm.) 22.9 (5.0) 18.7 (4.7) Rey fig. (Del.) 21.2 (4.8) 16.5 (5.1) Story WMS (Imm.) 9.7 (1.4) 8.6 (1.7) Story loss WMS 1.2 (1.1) 2.9 (1.9) 18

19 COGNITIVE DEFICITS IN OSAS CONTROLS BASELINE A B Executive functions Rey fig. copy 31.2 ( (3.5) Block design 10.1 (2.7) 8.4 (2.0) Pict. Arrangement 11.0 (1.2) 6.9 (1.6) Mazes (err.) 0.7 (0.8) 3.6 (1.2) Trail B (sec) 70.4 (23.3) 95.4 (33.2) Verbal fluency 40.2 (11.2) 28.2 (9.9) Manual dexteriry Purdue pegboard 15.2 (0.8) 11.9 (1.1) From Bédard,et al. Sleep

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25 Examination v Tongue v Palate v Uvula v Tonsils v Nasal cavity v Hyoid v Mandible v Maxilla 25

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39 LOC ROC 39 39

40 Differential Amplifier Differential Amplifier Anterior Tibialis EMG Differential Amplifier 40 Sleep Aca demic Awa rd 40

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52 Treatment v Nonsurgical modalities v Surgical modalities 52

53 Nonsurgical Treatment v Weight loss v Sleep hygiene v Pharmacotherapy v Nasal continuous positive airway pressure v Oral appliances 53

54 Surgical Treatments for OSA v Tracheostomy Drastic option for patients whose breathing is severely compromised (morbidly obese, hypoxemic, or emergency status) v UPPP (uvulopalatopharyngeoplasty) Removes uvula and upper airway soft tissue Reduced AHI by half in only 30-50% of cases v LAUPP (out-patient, laser assisted UPPP) No more successful than UPPP Best indication for snorers with no or mild OSA 54

55 Surgical Treatments (con t) v Cranialfacial surgery: Reshape facial bones v Radio frequency ablation (RFA): Stiffen soft tissue to reduce flutter, reduce tongue thickness, or shrink nasal turbinates Best indication for snorers with no or mild OSA Long term effectiveness unknown v Gastric bypass to reduce obesity: Patients may show a return of sleep apnea 55

56 Surgical Treatments (con t) v Other surgical options designed to improve airway patency: Tonsillectomy Adenoidectomy Correction of deviated nasal septum 56

57 Mechanical Treatments v Nasal CPAP most successful and common treatment Pressurized air delivery via nasal mask (or pillows ) attached by tubing to a compressor v Oral Appliances (mouth pieces) Purpose is to either hold the tongue forward or move the lower jaw forward 80% effective in controlling snoring and mild to moderate OSA; 30% effective in severe OSA Best results for positional apnea 57

58 CPAP THERAPY m Most successful and commonly used medical treatment m Normalizes sleep architecture and abolishes nocturnal hypoxemia m Improves EDS and cognitive functioning m Residual EDS and deficits in executive functions 58

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60 CPAP 60

61 NOCTURNAL SLEEP IN OSAS: Effect of CPAP CONTROLS BASELINE TREATED p APNEICS APNEICS A B C B-C Sleep % Wakening 10.7 (6.1) 12.7 (9.4) 12.9 (3.3) NS % Stage (3.6) 33.4 (21.7) 17.0 (6.5) * % Stage (6.4) 54.0 (20.8) 59.8 (9.4) NS % SWS 10.6 (5.8) 2.5 (3.1) 8.6 (7.0) * % REM 15.2 (5.9) 9.9 (3.4) 15.5 (6.1) ** Nb of awakenings 33.7 (11.1) 75.7 (55.0) 31.7 (15.7) * Nb of stage shifts (34.7) (222.3) (70.7) * From Bédard,et al. Sleep

62 COGNITIVE DEFICITS IN OSAS: Effect of CPAP CONTROLS BASELINE APNEICS TREATED p APNEICS p A B C B-C A-C General functioning Full Scale IQ (8.1) (8.9) (8.7) *** NS Verbal IQ (9.2) (9.9) (8.6) NS NS Performance IQ (7.4) (7.9) (7.9) *** NS Attention Digit Symbol 8.5 (2.1) 7.2 (1.2) 8.9 (1.8) ** NS Letter Cancellation 1.1 (0.6) 4.0 (3.2) 1.5 (4.6) * NS Memory Rey fig. (Imm.) 22.9 (5.0) 18.7 (4.7) 19.4 (6.3) NS NS Rey fig. (Del.) 21.2 (4.8) 16.5 (5.1) 17.2 (7.1) NS NS Story WMS (Imm.) 9.7 (1.4) 8.6 (1.7) 10.8 (3.2) * NS Story loss WMS 1.2 (1.1) 2.9 (1.9) 1.5 (1.3) * NS 62

63 COGNITIVE DEFICITS IN OSAS: Effect of CPAP CONTROLS BASELINE TREATED p p APNEICS APNEICS A B C B-C A-C Executive functions Rey fig. copy 31.2 ( (3.5) 30.5 (2.4) ** NS Block design 10.1 (2.7) 8.4 (2.0) 10.5 (1.9) ** NS Pict. Arrangement 11.0 (1.2) 6.9 (1.6) 8.8 (2.2) ** * Mazes (err.) 0.7 (0.8) 3.6 (1.2) 2.8 (1.0) * ** Trail B (sec) 70.4 (23.3) 95.4 (33.2) 88.0 (14.3) NS * Verbal fluency 40.2 (11.2) 28.2 (9.9) 29.9 (14.5) NS * Manual dexteriry Purdue pegboard 15.2 (0.8) 11.9 (1.1) 13.5 (1.4) ** NS From Bédard,et al. Sleep

64 CPAP Compliance v Two main issues with adherence: 1. Drop outs: o 5-30% of patients discontinue using CPAP 2. Failure to use CPAP as prescribed: o About 50% of patients use CPAP at a minimally acceptable level,, defined as at least 4hrs on 70% of nights o Average usage rates are hrs per night, which is probably less than optimal 64

65 Improving CPAP Compliance v Supportive and cognitive-behavioral techniques are moderately successful Support groups, verbal reinforcement strategies, patient education programs, bibliotherapy, motivational interviewing, systematic desensitization, sensory awareness techniques Systematic desensitization helps prevent discontinuation of CPAP Motivational interviewing is most promising for increasing nightly use time 65

66 Nonsurgical Treatment v Weight loss Get below trigger weight Diet, exercise, bariatric surgery, medications v Sleep hygiene Avoidance of sedatives Positional changes 66

67 Alternative Treatment Strategies v Combined surgical and mechanical treatments Oral appliance may be beneficial after a surgical option that opens nasal airway v Pharmacological treatments There are no successful respiratory stimulants REM suppressants may be beneficial for patients with REM-related apnea 67

68 Behavioral Treatments for OSA v Sleep position training v Weight loss v Modifying lifestyle behaviors Increasing exercise Reducing alcohol use Quitting smoking 68

69 Sleep Position Training v Tennis ball therapy (T-shirt method) Sewn tennis ball to back of pajama top makes supine position uncomfortable May be effective in controlling snoring Few studies have tested the effectiveness of this method, but one study showed a lowering of blood pressure 69

70 Sleep Position Training (con t) v Posture alarm (position monitor) Not all patients can be successfully trained to refrain from supine sleep after using this device for 8 weeks It is unknown how long this training can be maintained without reinforcement In one study of positional OSA, patients showed the best outcome when this treatment was combined with an oral appliance. Patients who were more obese and who had more severe apnea had least successful outcomes 70

71 Weight Loss v Difficult and slow process Patient may require alternative treatment such as CPAP while losing weight Patient often benefits from group treatment and support of spouse in changing eating behaviors Patient should abstain from alcohol use o o High caloric content Reduces tone of upper airway muscles, causing louder and more frequent snoring as well as increased number and length of respiratory pauses 71

72 Weight Loss Rules v Keep a daily record v Eat 3 meals a day with no snacks v Drink water and avoid soft drinks v Reduce portion size v Slow down eating v Stop eating when full v Don t skip breakfast 72

73 Exercise v Using CPAP may provide patient with more energy to engage in physical activities Ways to increase activity: o Take a walk at lunch time o Use stairs instead of elevator o Park farther away from your destination o Ride a bicycle o Stand up when talking on the phone 73

74 Smoking v Patient must be motivated v Probability of success is increased by a program combining behavior change with pharmacological elements 74

75 EFFICACIA DEI TRATTAMENTI 75

76 Obstructive Sleep Apnea Syndrome (OSAS) v Primary goal is to eliminate sleep disordered breathing (SDB) Most behavioral intervention studies have used Apnea Hypopnea Index (AHI) as the primary outcome v Obesity is a major risk factor Adipose tissue in the upper airway Hypotonality of airway dilating muscles Reduced residual lung volume 76

77 Weight Loss for OSAS v Weight loss is a conservative intervention Weight loss reduces the amount of adipose tissue in the oropharynx, improves airway caliber, reduces airway collapsibility, increases residual volume in the lungs and reduces respiratory effort Significant and maintained weight loss can cure OSAS Most effective approach involves a multidisciplinary team, frequent provider contacts, and regular physical activity 77

78 Weight Loss for OSAS (con t) v Most studies investigating weight loss in OSAS patients are uncontrolled with small sample sizes v Collectively, weight loss studies have yielded the following findings: A decrease in weight is associated with a disproportionately larger decrease in apnea events o Peppard et al.: Each percentage change in weight was associated with an approximate 3% change in the AHI 78

79 Weight Loss for OSAS (con t) v Weight loss findings: Weight loss through diet alone or diet and exercise is associated with the following: o o o o o o o o o Reduction in AHI/RDI/SDB and snoring frequency Improved oxygenation Improved daytime sleepiness, mood, and quality of life Improved global measures of sleep Improved blood pressure Improved lung vital capacity and functional residual capacity Improved resistance to upper airway collapse Increased upper airway pressure Decreased soft palate width 79

80 Weight Loss for OSAS (con t) v Weight loss findings (con t): For mild to moderate OSAS, physical conditioning may have an additional or synergistic benefit with weight loss The benefits of weight loss are evident in patients with varying severity of sleep apnea and baseline body weight Studies using weight loss as a conservative control treatment to evaluate CPAP efficacy: o Weight loss was associated with improved AHI. Weight loss patients showed comparable improvement as the CPAP group on steer-clear task and cognitive tests 80

81 Weight Loss for OSAS (con t) v Weight loss findings (con t): Long-term weight loss: o o o Some patients are cured of OSA and/or snoring Relapse of OSAS (by weight gain) is frequent among those previously cured by dietary weight loss (only half of patients remain cured) An individual s response to weight loss is highly variable Weight loss in morbidly obese OSA patients: o Moderate weight loss can lead to substantial improvement in SDB. However, this is not sufficient to produce significant clinical improvement to be used as the primary treatment in morbidly obese patients with severe OSAS 81

82 Weight Loss for OSAS (con t) v Summary of weight loss findings: Weight loss has a beneficial effect on SDB Modest weight loss is likely to reduce the severity of SDB and the risk of developing clinically significant OSAS Even a small degree of weight loss is associated with decreased snoring, decreased AHI, and decreased collapsibility of the airway Weight loss is efficacious in the short-term, but long- term benefits remain to be established The combination of weight loss with other behavioral interventions may be beneficial 82

83 Positional Sleep Apnea v Frequency and severity of SDB is influenced by position in 50-60% of patients v AHI in OSAS patients may be twice as high in supine position compared to lateral position v Positional Sleep Apnea Syndrome: The phenomena in which the AHI during supine sleep position is 2 or more times the AHI during lateral sleep position 83

84 Sleep Position Training for OSAS v Sleep position training for positional sleep apnea Interventions that decrease time spent in supine sleep position should o o Diminish the impact of obesity on the residual capacity of the lungs Reduce the effort required for the mechanics of respiration Positional therapy is a conservative intervention indicated for non-obese patients with position- dependent SDB who don t have significant associated pathologies (oxygen desaturation, cardiac arrhythmias, excessive daytime sleepiness) 84

85 Sleep Position Training for OSAS (con t) v Positional sleep training methods Tennis ball, backpack and softball, foam rubber wedges or sandbag placements, position monitoring device (alarm), elevated upright sleeping position v Position monitoring device (Cartwright et al.) Significantly increased the proportion of total sleep time that the patients spent in the lateral positions Intervention was associated with decreases in the AHI and the number of oxygen desaturation events Learning from one-night positional training was maintained at 3 months in some patients 85

86 Sleep Position Training for OSAS (con t) v Instructions to avoid supine sleep (Cartwright et al.) Patients instructed to diet, exercise, avoid alcohol, and avoid supine sleep (compared to position monitoring alarm group): o o o Showed greater improvement in AHI and comparable ability to avoid supine position The findings support the therapeutic benefit of avoiding the supine position Some patients can learn to avoid supine posture on their own 86

87 Sleep Position Training for OSAS (con t) v Elevated upright sleeping position (McEvoy et al.) Compared to supine sleep, the 60-degree position sleep was associated with a reduction in the AHI and did not disrupt sleep architecture Obese patients and patients who show greater degree of hypoxemia had greater response to this intervention than non-obese patients Significant reduction of SDB can be facilitated by the adoption of a more upright sleep posture 87

88 Sleep Position Training for OSAS (con t) v Foam rubber wedges to maintain lateral sleeping position in snorers (Braver and Block) Resulted in 19% reduction of AHI Snoring was not improved by this intervention v Backpack and softball (Jovic et al.) Significantly reduced time spent in supine position Showed similar improvements in sleep architecture, arousal frequency, daytime sleepiness, mood, and cognitive tests as CPAP Reduced AHI, but not as much as CPAP 88

89 Sleep Position Training for OSAS (con t) v Summary of efficacy studies Although there are only a handful of studies on the efficacy of positional therapy, findings consistently support the therapeutic benefits of this intervention for persons with positional sleep apnea syndrome o o Positional training is a promising noninvasive, inexpensive treatment either as an interim, single therapy, or in combination with other therapies Some benefits of positional intervention may be comparable to that provided by CPAP therapy. Positional therapy may be an effective alternative treatment to CPAP, at least for the short term 89

90 Alternative Therapies for OSAS v Cervical Positional Therapy (Kushida et al.) A custom-designed cervical pillow designed to extend head position to modify upper airway Subjects reported subjective sleep improvement Objective benefits only in patients with mild disease More studies are needed to establish the efficacy of this intervention v Myofunctional Therapy Targets improving tone of the upper airway muscles Has not been scientifically tested 90

91 Alternative Therapies for OSAS (con t) v Sleep Hygiene No published studies on the efficacy of this as a single intervention Alcohol and SDB o o No studies show that eliminating alcohol reduces SDB Studies have demonstrated that alcohol ingestion near bedtime exacerbates SDB (increases apneas and hypoxic events) and can cause male snorers to develop apnea Sleep deprivation o Sleep deprivation may increase severity of OSA, but no studies show that obtaining adequate sleep improves SDB 91