Efficacy of adaptive servoventilation in treatment of complex and central sleep apnea syndromes

BACKGROUND: Complex sleep apnea syndrome (CompSAS) is recognized by the concurrence of mixed or obstructive events with central apneas, the latter predominating on exposure to continuous positive airway pressure (CPAP). Treatment of CompSAS or central sleep apnea (CSA) syndrome with adaptive servoventilation (ASV) is now an option, but no large series exist describing the application and effectiveness of ASV. METHODS: Retrospective chart review of the first 100 patients who underwent polysomnography using ASV at Mayo Clinic Sleep Center. RESULTS: ASV titration was performed for CompSAS (63%), CSA (22%), or CSA/Cheyne Stokes breathing patterns (15%). The median diagnostic sleep apnea hypopnea index (AHI) was 48 events per hour (range, 24 to 62). With CPAP, obstructive apneas decreased, but the appearance of central apneas maintained the AHI at 31 events per hour (range, 17 to 47) [p = 0.02]. With bilevel positive airway pressure (BPAP) in spontaneous mode, AHI trended toward worsening vs baseline, with a median of 75 events per hour (range, 46 to 111) [p = 0.055]. BPAP with a backup rate improved the AHI to 15 events per hour (range, 11 to 31) [p = 0.002]. Use of ASV dramatically improved the AHI to a mean of 5 events per hour (range, 1 to 11) vs baseline and vs CPAP (p < 0.0001). ASV also resulted in an increase in rapid eye movement sleep vs baseline and CPAP (18% vs 12% and 10%, respectively; p < 0.0001). Overall, 64 patients responded to the ASV treatment with a mean AHI < 10 events per hour. Of the 44 successful survey follow-up patients contacted, 32 patients reported some improvement in sleep quality. CONCLUSION: The ASV device appears to be an effective treatment of both CompSAS and CSA syndromes that are resistant to CPAP.     

Polysomnographic characteristics of adolescents with asthma and low risk for sleep-disordered breathing

Purpose

The aim of this study was to describe the polysomnographic characteristics of adolescents with asthma who are at low risk for sleep-disordered breathing (SDB) based on the Pediatric Sleep Questionnaire (PSQ).

Methods

Overnight polysomnography was performed on 85 adolescents with asthma and a score <?0.33 on the PSQ. The Asthma Control Questionnaire was used to define “well-controlled” versus “inadequately controlled” asthma.

Results

Mean age of participants was 14.5?±?1.6 years (range, 11 to 17 years), 63.5% were girls, 57.6% were Caucasians, and the mean body mass index percentile was 65.1?±?26.5. Asthma was well-controlled in 51.7% of the adolescents and inadequately controlled in 15.3%. Mean sleep efficiency (SE) was 88.0?±?11.1%, and 24.7% had SE?<?85%. Mean wakefulness after sleep onset (WASO) was 40.9?±?44.0 min, and the mean arousal index was 10.8?±?5.6 per hour. The mean apnea/hypopnea index (AHI) was 2.3?±?4.2, and 29.4% of participants had SDB (defined by an AHI?≥?2). Compared with normative values, adolescents with asthma had more nocturnal awakenings and WASO, and less REM sleep. SDB risk was higher in boys [odds ratio?=?4.6 (confidence interval 1.4–14.7), p?=?0.01]. Asthma control did not impact sleep and respiratory parameters, with no differences found between youth with well-controlled and inadequately controlled asthma.

Conclusions

Adolescents with asthma are at increased risk of sleep-disordered breathing and suffer from disturbances in sleep continuity with more arousals and sleep fragmentation. Study results highlight the importance of proper screening for sleep-disordered breathing in adolescents with asthma.

     

Accuracy of autotitrating CPAP to estimate the residual Apnea–Hypopnea Index in patients with obstructive sleep apnea on treatment with autotitrating CPAP

Objective  

Autotitrating continuous positive airway pressure (auto-CPAP) devices now have a smart card (a pocket-sized card with embedded integrated circuits which records data from the CPAP machine such as CPAP usage, CPAP pressure, large leak, etc.) which can estimate the Apnea–Hypopnea Index (AHI) on therapy. The aim of this study was to determine the accuracy of auto-CPAP in estimating the residual AHI in patients with obstructive sleep apnea (OSA) who were treated with auto-CPAP without a CPAP titration study.     

Tolerance and intolerance to continuous positive airway pressure

Nasal continuous positive airway pressure (CPAP) is the most effective and widely used therapy for obstructive sleep apnea. As with any chronic therapy, long-term compliance has a significant impact on its effectiveness. Only about half of patients use CPAP for more than half the night on five or more nights per week. Approximately 4 hours of CPAP therapy per night appears to significantly improve daytime alertness and performance. Four hours of therapy also seems to improve sleep-disordered breathing for the remainder of the night. Patient education and close follow-up and intervention appear to improve long-term tolerance. Autotitration CPAP or bilevel positive airway pressure systems are no more effective or better tolerated than conventional CPAP therapy. They may be useful options if patients have been unable to tolerate conventional CPAP therapy.     

Insomnia complaints in patients evaluated for obstructive sleep apnea

Obstructive sleep apnea (OSA) and insomnia are among the most common sleep diagnoses encountered in the sleep clinic population, however little is known about potential interactions or associations between the two disorders. This retrospective, cross-sectional study was designed to determine the prevalence of insomnia complaints in patients undergoing evaluation for OSA and to ascertain which clinical and polysomnographic features are associated with insomnia. Of 255 consecutive patients who underwent polysomnography for clinically suspected OSA, 54.9% reported a complaint of insomnia: 33.4% reported difficulty initiating sleep, 38.8% difficulty maintaining sleep, and 31.4% early morning awakenings. Insomnia complaints were noted more commonly in patients without significant sleep-disordered breathing [apnea hypopnea index (AHI)<10; 81.5%] vs those with sleep-disordered breathing (AHI≥10; 51.8%); p=0.01. Clinical factors associated with insomnia included female gender, psychiatric diagnoses, chronic pain, the absence of regular alcohol use, restless leg symptoms, and reports of nocturnal kicking. Polysomnographic factors associated with insomnia included lower AHI and lower desaturation index (DI). In the subgroup of patients with significant sleep-disordered breathing (AHI≥10, n=228), there was no association between insomnia complaints and AHI or DI. These results suggest that insomnia is a common complaint in patients being evaluated for OSA, but it is not strongly associated with sleep-disordered breathing and may instead reflect other coexisting factors.     

Primary pulmonary hypertension with central sleep apnea: sudden death after bilevel positive airway pressure therapy

An obese 23-year-old man with sleep-disordered breathing and primary pulmonary hypertension (PPH) had been administered oral beraprost sodium, anticoagulant warfarin, and home oxygen therapy, at another hospital as treatment for the PPH, but he had not experienced any symptomatic improvement. The patient had a body mass index of 32.4kg/m2, and complained of fatigue, shortness of breath on exertion, excessive daytime sleepiness, and snoring. Arterial blood gas analysis showed a PaO2 and a PaCO2 of 70.9 and 31.2mmHg, respectively. A polysomnographic study revealed central sleep apnea with an apnea-hypopnea index (AHI) of 29.7episodes/h. The patient showed improvement of daytime sleepiness after starting nocturnal nasal bilevel positive airway pressure (BiPAP) therapy for the central sleep apnea, but his pulmonary hypertension, measured in the daytime, worsened. The patient died suddenly while walking to the bathroom in the morning 1 month after initiation of BiPAP therapy. It is necessary to consider the possibility of sudden death when nasal BiPAP therapy is given to a PPH patient with central sleep apnea.     

Utility of split-night polysomnography in the diagnosis of upper airway resistance syndrome

Purpose  Split-night polysomnography can both establish the diagnosis and titrate continuous positive airway pressure (CPAP) during a single study in patients with sleep-disordered breathing. We sought to determine if split-night polysomnography could be effectively used in upper airway resistance syndrome (UARS) without diminishing diagnostic accuracy or success of CPAP titration. Methods  Consecutive patients diagnosed with UARS were included. Split-night studies were performed in patients meeting predefined criteria. We compared data between those undergoing traditional and split-night polysomnography. Results  We included 100 consecutive patients (41.2 ± 7.4 years, 54% men). Forty-six underwent split-night polysomnography. Groups were similar at baseline. There were no differences in polysomnography or success rate of CPAP titration. Among those not undergoing split-night studies, the mean time between diagnostic polysomnography and CPAP titration was 71.9 ± 49.0 days. Conclusions  Split-night polysomnography can be effectively utilized to diagnose UARS and initiate CPAP therapy. This practice can reduce the number of studies needed and obviate the inherent delay in initiating CPAP therapy. The authors have no financial interests to disclose. The opinions expressed herein are those of the authors are not to be construed as official or as reflecting the policies of either the Department of the Army or the Department of Defense.     

Prevalence of sleep-disordered breathing and continuous positive airway pressure compliance: results in chinese patients with first-ever ischemic stroke

OBJECTIVE: To assess the prevalence of sleep-disordered breathing (SDB), continuous positive airway pressure (CPAP) acceptance, and CPAP compliance in patients who have experienced ischemic stroke. DESIGN: A case-controlled study. SETTING: A university hospital. MEASUREMENTS AND RESULTS: We recruited 23 women and 28 men, who were admitted to the hospital within 4 days of stroke onset, with a mean (+/- SD) age of 64.2 +/- 13.0 years and a body mass index (BMI) of 24.3 +/- 4.4 kg/m(2) for this study. Twenty-seven patients (53%) and 9 patients (17.6%), respectively, reported a history of snoring and severe daytime sleepiness prior to experiencing a stroke, while the mean Epworth sleepiness scale score was 6.8 +/- 3.6. Polysomnography revealed 34 patients (67%) with an apnea-hypopnea index (AHI) of > or = 10 events per hour, 31 patients (61%) with an AHI of > or = 15 events per hour, and 25 patients (49%) with an AHI of > or = 20 events per hour. Significant obstructive SDB, defined as an AHI of > or = 20/h, was more prevalent in ischemic stroke patients than in control subjects (49% vs 24%, respectively; p = 0.04) and was associated with a higher BMI (p = 0.046). Among the 34 patients with an AHI of > or = 10/h, CPAP titration was tolerated by 16 patients, but only 4 patients who had typical sleep apnea features proceeded to home CPAP treatment with objective compliance over a period of 3 months of 2.5 +/- 0.6 h per night. A subgroup of 20 patients not receiving CPAP showed partial spontaneous improvement of SDB at 1 month (baseline AHI, 32.3 +/- 17.6 events per hour; AHI at 1 month, 23.0 +/- 18.8 events per hour; p = 0.01) with a trend toward improvement for the obstructive but no significant change for the central events, whereas no improvement in AHI was noted for the four patients receiving CPAP. CONCLUSION: There is a high prevalence of obstructive SDB in patients who have experienced acute ischemic stroke, which, in many cases, is different from classic obstructive sleep apnea syndrome, and this is reflected by the lack of significant sleepiness, poor CPAP acceptance, and partial spontaneous improvement at 1 month.     

Is automatic CPAP titration as effective as manual CPAP titration in OSAHS patients? A meta-analysis

Purpose  

It is costly and time-consuming to conduct the standard manual titration to identify an effective pressure before continuous positive airway pressure (CPAP) treatment for obstructive sleep apnea (OSA) patients. Automatic titration is cheaper and more easily available than manual titration. The purpose of this systematic review was to evaluate the effect of automatic titration in identifying a pressure and on the improvement of apnea/hyponea index (AHI) and somnolence, the change of sleep quality, and the acceptance and compliance of CPAP treatment, compared with the manual titration.     

Effectiveness of adaptive servo-ventilation

Adaptive servo-ventilation (ASV) has been developed as a specific treatment for sleep-disordered breathing, in particular Cheyne-Stokes respiration with central sleep apnea (CSA). Heart failure patients often have sleep-disordered breathing, which consists of either obstructive sleep apnea (OSA) or CSA. Other medical conditions, such as stroke, acromegaly, renal failure, and opioid use may be associated with CSA. Continuous positive airway pressure (CPAP) therapy is widely used for patients with OSA, but some of these patients develop CSA on CPAP, which is called treatment-emergent CSA. CPAP can be useful as a treatment for these various forms of CSA, but it is insufficient to eliminate respiratory events in approximately half of patients with CSA. As compared to CPAP, ASV may be a better option to treat CSA, with sufficient alleviation of respiratory events as well as improvement of cardiac function in heart failure patients. In patients without heart failure, ASV can also alleviate CSA and relieve their symptom. Recently, ASV has been widely used for patients with various forms of CSA. ASV may be also used in the setting without CSA, but it should be assessed more carefully. Clinicians should have a better understanding of the indications for ASV in each setting.     

Nocturnal noninvasive ventilation

Nocturnal noninvasive ventilation (NNV), the provision of ventilatory assistance via a noninvasive interface mainly during sleep, has assumed an important role in the management of chronic hypoventilatory syndromes. This review focuses on recent developments related to the use of NNV to treat various forms of chronic respiratory failure or insufficiency. In the past, NNV has been used mainly to treat respiratory insufficiency in patients with neuromuscular disease (NMD) or chest wall deformity; it should be instituted when these patients have orthopnea or daytime symptoms associated with nocturnal hypoventilation. An emerging application is to treat obesity-hypoventilation syndrome, particularly in continuous positive airway pressure (CPAP) failures. Additionally, it has a role in managing some patients with obstructive sleep apnea who are hypoventilating or find the lower expiratory pressure with bilevel positive pressure ventilators more tolerable than with CPAP alone. NNV to treat severe, stable COPD remains controversial, although a subgroup of patients with hypercapnea and sleep-disordered breathing (SDB) seems most likely to respond favorably. NNV to treat central SDB in patients with congestive heart failure continues to be investigated. Recent findings from a Canadian CPAP trial were disappointing, but preliminary results on a novel adaptive NNV mode are promising.     

Improving Heart Rate Variability in Sleep Apnea Patients: Differences in Treatment with Auto-titrating Positive Airway Pressure (APAP) Versus Conventional CPAP

The effect of positive airway pressure treatments in different modalities on the cardiovascular consequences of the disease in sleep apnea patients is still unclear. We aimed to compare auto-titrating positive airway pressure (APAP) and conventional continuous positive airway pressure (CPAP) in terms of improving heart rate variability (HRV) in obstructive sleep apnea patients. This was a prospective study done in a tertiary research hospital. All patients underwent a manual CPAP titration procedure to determine the optimal pressure that abolishes abnormal respiratory events. Then patients underwent two treatment nights, one under APAP mode and one under conventional CPAP mode with a 1-week interval. Forty newly diagnosed obstructive sleep apnea patients were enrolled in the study. We compared heart rate variability analysis parameters between the APAP night and the CPAP night. This final analysis included the data of 28 patients (M/F: 22/6; mean age = 46 ± 10 years). Sleep characteristics were comparable between the two treatment nights, whereas all-night time domains of HRV analysis such as HF, nuLF, and LF/HF were different between APAP and CPAP nights (2.93 ± 0.31 vs. 3.01 ± 0.31; P = 0.041; 0.75 ± 0.13 vs. 0.71 ± 0.14; P = 0.027; and 4.37 ± 3.24 vs. 3.56 ± 2.07; P = 0.023, respectively). HRV analysis for individual sleep stages showed that Stage 2 LF, nuLF, nuHF, LF/HF parameters entirely improved under CPAP treatment whereas APAP treatment resulted in nonsignificant changes. These results suggest that despite comparable improvement in abnormal respiratory events with APAP or CPAP treatments, CPAP may be superior to APAP in terms of correcting cardiovascular alterations in sleep apnea patients.     

Efficacy of positive airway pressure and oral appliance in mild to moderate obstructive sleep apnea

The efficacy of currently recommended treatments is uncertain in patients with mild to moderate obstructive sleep apnea (apnea-hypopnea index [AHI], 5-30). A group of 114 sleep clinic patients with an AHI of 5-30 have participated in a randomized controlled crossover trial of 3 months of treatment with each of nasal continuous positive airway pressure (CPAP), a mandibular advancement splint, and a placebo tablet. Outcomes were sleep fragmentation and hypoxemia, daytime sleepiness, quality of life, neurobehavioral function, and blood pressure. Both active treatments improved sleep outcomes, but positive airway pressure had a greater effect. The quality of life, symptoms, and subjective but not objective sleepiness improved to a similar degree with both treatments; however, many of the improvements seen in neuropsychologic function and mood were not better than the placebo effect. Some aspects of nocturnal blood pressure were improved with the splint but not with CPAP. This study has shown that although both CPAP and mandibular advancement splint effectively treated sleep-disordered breathing and sleepiness, the expected response in neurobehavioral function was incomplete. This may be due to the splint having a lesser therapeutic effect and CPAP being poorly tolerated and therefore used less in this patient group.     

The role of high-frequency jet ventilation in the treatment of Cheyne-Stokes respiration in patients with chronic heart failure

BACKGROUND: Cheyne-Stokes respiration with central sleep apnea (CSR-CSA) is common in patients with severe cardiac failure. Various modes of positive airway pressure have been suggested as treatments.The authors hypothesized that high frequency jet ventilation (HFJV) can improve central sleep apnea in patients with chronic heart failure. METHODS: Eleven subjects with stable, optimally treated chronic heart failure and Cheyne-Stokes respiration were tested untreated and on four treatment nights in random order: nasal oxygen (4 L/min), continuous positive airway pressure (CPAP) (mean 9.3 cm H(2)O), bilevel positive airway pressure (BiPAP)(mean 12.0/5.3 cm H(2)O), or HFJV(60 approximately 80 breaths per minute) during polysomnography (EMBLA, Flaga, Reykjavik, Iceland). RESULTS: The apnea-hypopnea index (AHI) declined from 30.9 +/- 8.3/h in untreated night to 23.6 +/- 6.6/h oxygen night and 18.5 +/- 5.0/h CPAP, 14.3 +/- 3.9/h BiPAP, and 20.1 +/- 4.1/h HFJV (all P < 0.001 versus control). There was no significant difference between the AHI of HFJV and that of CPAP (P = 0.541). Arousal index decreased from 31.4+/-13.2/h untreated to 25.0 +/- 7.1/h oxygen and 13.6 +/- 4.7/h CPAP, to 13.7 +/- 4.9/h BiPAP and 14.4 +/- 4.7/h HFJV. HFJV had the similar effect to the other therapeutic groups in arousal index (P > 0.05). There were large increases in slow-wave and rapid eye movement (REM) sleep with HFJV. All subjects preferred HFJV to CPAP. CONCLUSIONS: One night of therapy with HFJV improved nocturnal breathing pattern and sleep quality in patients with Cheyne-Stokes respiration in chronic heart failure. HFJV therapy for sleep and breathing were the same as those during a nasal CPAP night. A long-term study of the effect of HFJV on cardiovascular function is needed.     

The effects of oxygen in patients with sleep apnea

The effects of 6 h of continuous low flow, nasally administered oxygen were compared with the effects of breathing air in 10 men and 2 women with obstructive sleep apnea and daytime hypersomnolence. The overall quality of sleep, sleep fragmentation, the pattern of breathing, nocturnal oxygenation, and the clinical effects on daytime hypersomnolence determined by multiple sleep latency testing were evaluated. We found that in non-REM sleep, breathing 3 L/min of oxygen increased baseline percent arterial oxyhemoglobin saturation and decreased both the rate of sleep-disordered breathing from 69 +/- 36 to 56 +/- 39 (mean +/- SD) (p less than 0.02) episodes per hour and the peak fall in arterial oxyhemoglobin saturation from 11.5 +/- 5.6% to 6.5 +/- 4.0% (p less than 0.001). In addition, oxygen significantly reduced the percentage of central and mixed sleep-disordered breathing events, thus increasing the percentage of obstructive sleep-disordered breathing events. In contrast, during REM sleep, neither the baseline nor the peak fall in oxyhemoglobin saturation during disordered breathing improved; however, there was a significant reduction in hourly sleep-disordered breeathing rate from 70 +/- 17 to 56 +/- 23 (p less than 0.02) episodes. These improvements in oxygenation and pattern of breathing were associated with improved sleep architecture characterized by a decrease in the number of awakenings from sleep and an increased total sleep time from 335 +/- 72 to 369 +/- 68 min (p less than 0.05). Although 7 of 12 patients felt more alert after oxygen therapy, there was no overall improvement in multiple sleep latency test results.(ABSTRACT TRUNCATED AT 250 WORDS)     

The effect of correction of sleep-disordered breathing on BP in untreated hypertension

OBJECTIVES: To compare BP response to 3 weeks of nasal continuous positive airway pressure (CPAP) in hypertensive patients with and without sleep-disordered breathing (SDB). DESIGN: A controlled, interventional trial of nasal CPAP in patients with and without SDB. Participants and setting: Twenty-four men, aged 30 to 60 years, with mild to moderate untreated hypertension recruited from employee health and primary care clinics. METHODS: Based on in-laboratory polysomnography, 14 hypertensive patients had SDB, defined by five or more episodes of apnea and hypopnea per hour of sleep (apnea-hypopnea index [AHI], > or = 5), and 10 had no SDB (AHI, < 5). We performed 24-h ambulatory BP monitoring on all patients at baseline, during CPAP, and after CPAP treatment. In patients with an AHI > or = 5, nasal CPAP was titrated to reduce the AHI to < 5. Patients with an AHI < 5 received CPAP of 5 cm H(2)O to control for any potential effect of CPAP per se on BP. Both groups received CPAP for 3 weeks. RESULTS: After adjusting for age and body mass index, the mean nocturnal systolic and diastolic BP changes after CPAP treatment in the SDB group were significantly different from those in the no-SDB group: -7.8 vs +0.3 mm Hg (p = 0.02), and -5.3 vs -0.7 mm Hg (p = 0.03), respectively. There was a similar, although statistically insignificant, difference in the adjusted mean daytime systolic and diastolic BP changes after CPAP treatment between the two groups (-2.7 vs +0.4 mm Hg and -2.3 vs -1.7 mm Hg, respectively). CONCLUSIONS: Three weeks of nasal CPAP treatment of SDB in hypertensive men caused the lowering of nocturnal systolic and diastolic BP values, suggesting that increased nocturnal BP in persons with hypertension was causally related to the apnea and hypopnea events of SDB.     

自动持续正压系统对睡眠呼吸障碍的诊治

目的探索简便、临床易于推广应用的睡眠呼吸障碍疾患的诊治手段。方法对１１例睡眠呼吸障碍患者同步进行经典的多导睡眠图监测和自动持续正压系统监测，将监测结果进行比较；对２３例已确诊的阻塞性睡眠呼吸暂停综合征（ＯＳＡＳ）患者使用自动持续正压系统治疗，并对治疗效果进行评价。各监测指标比较采用ｔ检验。结果（１）自动持续正压系统与多导睡眠图相比较，自动持续正压系统虽无睡眠及心电记录，但可记录鼾声及上气道阻力；最高及最低血氧饱和度、最长呼吸暂停时间、呼吸暂停低通气（ＡＨＩ）指数等监测结果，两者相比，差异无显著性（Ｐ＞０．０５）；自动持续正压系统诊断ＯＳＡＳ的敏感性为７０％，特异性为１００％。（２）ＯＳＡＳ患者使用自动持续正压系统治疗后症状改善；ＡＨＩ显著减低，最低血氧饱和度显著升高（Ｐ＜０．００１）；此外，平均和最高压力与９５％可信压力比较差异有显著性。结论自动持续正压系统使用简便，并减轻了技术员监测时的劳动强度；在持续正压通气（ＣＰＡＰ）治疗时可采用９５％可信限所需的压力     

The accuracy of autotitrating CPAP-determined residual apnea–hypopnea index

Purpose

Autotitrating continuous positive airway pressure (auto-CPAP) devices not only titrate CPAP pressures but also measure residual respiratory events. The aim of the present study was to determine the accuracy of auto-CPAP-derived residual apnea–hypopnea index (AHI).

Methods

We studied 137 consecutive patients (72.3% men) with obstructive sleep apnea from January 2008 to December 2010 who underwent in-laboratory overnight polysomnography (PSG) using auto-CPAP. We excluded patients with comorbidities like congestive heart disease, chronic obstructive pulmonary disease, or hypoventilation syndromes and patients with central sleep apnea. Residual AHI obtained from the auto-CPAP device by smart card (CPAP-AHI) was compared simultaneously with AHI from an overnight PSG on auto-CPAP (PSG-AHI) using Bland–Altman analysis and Wilcoxon signed-rank test.

Results

The mean AHI on the diagnostic study was 45.08?±?1.8. During the titration, auto-CPAP markedly suppressed the respiratory events (PSG-AHI, 3.40?±?0.20). On the other hand, CPAP-AHI was 3.35?±?0.17. Bland–Altman analysis showed good agreement between auto-CPAP-AHI and PSG-AHI (AHI mean difference of 0.05, and the limits of agreement for the AHI were from +4.9 to ?4.8). Two methods have also been compared with paired samples t test and no statistically significant difference was found (p?>?0.05).

Conclusion

Auto-CPAP can identify residual respiratory events equivalent to the use of PSG in a selected population.     

The need for pressure changes in CPAP therapy 2–3 months after initial treatment

Objective  

The aim of the study was to investigate the need for pressure change in patients with sleep-disordered breathing (SDB) several weeks after therapy initiation. We prospectively studied 905 consecutive patients (740 men and 165 women) with SDB and therapeutic intervention with continuous positive airway pressure (CPAP)/bilevel PAP.     

稳定期慢性充血性心力衰竭患者睡眠呼吸障碍

目的了解稳定期、已得到良好治疗的慢性充血性心力衰竭(心衰)患者的睡眠呼吸障碍的发生情况及睡眠呼吸障碍对心衰的影响.方法应用多导睡眠监护仪(Polywin1000,RespironicsInc.)对稳定期充血性心衰患者进行监测.结果病人分为两组,Ⅰ组(21例)A-H指数≤15,Ⅱ组(15例,占41.7%)A-H指数》15.Ⅱ组A-H指数为16.8～78.8,平均42.6±15.5,其中阻塞性AHI为11.1±8.4,而中枢性AHI为31.5±9.6.同时,Ⅱ组有着显著多的醒觉指数,为36.8±21.3(Ⅰ组为19.4±11.2),这直接与呼吸暂停及低通气指数有关,并与睡眠中最低血氧饱和度[Ⅱ组(76.7±4.6)%,Ⅰ组(86.5±2.8)%、更低的左心室射血分数[Ⅱ组(24.2±8.8)%,Ⅰ组(31.5±10.6)%]有关.结论稳定期慢性充血性心衰患者有着很高的严重的睡眠呼吸障碍的发生率,主要为伴中枢性睡眠呼吸暂停的周期性呼吸.睡眠呼吸障碍的发生与严重的夜间氧合血红蛋白饱和度的下降及过多的觉醒有关.严重的未经治疗的睡眠呼吸障碍可能影响左心室功能,并能加剧充血性心衰患者的死亡.