The effect of nightly nasal CPAP treatment on underlying obstructive sleep apnea and pharyngeal size

Nasal continuous positive airway pressure (CPAP) is an effective treatment for obstructive sleep apnea (OSA). It is usually prescribed for nightly use; however, recent studies show that patients often do not wear the appliance consistently. Previous studies have also suggested that nasal CPAP may improve a patient's underlying OSA even when the mask is not in place. We investigated 12 men with OSA to see if nasal CPAP used nightly for six weeks would improve their underlying sleep-disordered breathing. We also studied pharyngeal volumes measured using magnetic resonance imaging and a computer-controlled digitizing pad. Patients with more severe OSA had improvement after six weeks; however, they still demonstrated significant OSA. Patients with less severe OSA did not have significant change. We were unable to show a significant difference in any patient's awake pharyngeal volumes. We conclude that patients with OSA should be encouraged to wear their nasal CPAP machines regularly.     

Correlations of sleep disorders with severity of obstructive airway disease in mustard gas-injured patients

Introduction  

Mustard gas has serious adverse effects on several organs and functions in humans. In this study, we analyzed potential correlations between obstructive airway disease and sleep disorders in Iranian mustard gas-injured patients.     

Sleepwalking precipitated by treatment of sleep apnea with nasal CPAP

A 33-year-old man with a long history of snoring, observed apneic episodes, and excessive daytime sleepiness, underwent all-night polysomnography, which demonstrated severe obstructive sleep apnea. During the nasal CPAP trial, two episodes of sleepwalking were observed during a period of delta sleep rebound.     

The effect of short-term nasal CPAP therapy in cases of obstructive sleep apnea syndrome

Recent studies have shown that nasal CPAP is very effective in the treatment of patients with obstructive sleep apnea syndrome (OSA). To clarify the characteristics of pulmonary function testing and to evaluate the effect of short term nasal CPAP therapy in 13 cases of OSA patients, nasal CPAP was used for 10 to 14 days and polysonography was performed on two consecutive nights without nasal CPAP and at one night with nasal CPAP. Pulmonary function tests and the Uchida-Kraepelin test were performed before the initiation of nasal CPAP therapy and also 7 to 14 days after the nasal CPAP therapy. Apnea index reduced significantly in all cases from 5.10 +/- 19.6 episodes/hour without therapy to 3.1 +/- 3.5 with nasal CPAP (p less than 0.001). Nasal CPAP significantly reduced the frequency of obstructive (p less than 0.001) and mixed apnea (p less than 0.01), but the frequency of central apnea did not change with nasal CPAP. During the nasal CPAP, mean nadir SaO2 rose from 87.3 +/- 2.9% to 92.7 +/- 1.1% (p less than 0.001) and the lowest SaO2 rose from 73.3 +/- 6.4% to 92.0 +/- 2.1% (p less than 0.001). Before the nasal CPAP therapy, daytime PaO2 was 80.6 +/- 6.4 Torr and closing capacity (CC)/FRC ratio was higher when patients were in a supine than in a sitting position. After short term nasal CPAP therapy, daytime PaO2 increased significantly (p less than 0.001), and FRC/TLC in a supine position increased and CC/FRC in a supine position decreased in some patients.(ABSTRACT TRUNCATED AT 250 WORDS)     

夜间经鼻面罩持续正压辅助通气治疗中枢性低通气

报告４例不同原因所致的中枢性低通气病人夜间应用经鼻面罩持续正压通气的疗效反应。４例病人分别于治疗前、吸氧２Ｌ／ｍｉｎ及应用通气治疗后行多导睡眠图检查比较夜间低通气及血氧情况，结果示单纯吸氧不能明显改善低通气次数和低氧情况，最低氧饱和度均＜５０％，低通气指数３例仍＞２０ｂ／ｈ（正常值＜５ｂ／ｈ），另１例为６４ｂ／ｈ；予以持续正压通气机通气治疗，压力调至６～１２ｃｍＨ２Ｏ（１ｃｍＨ＿２Ｏ＝０．０９８ｋＰａ）时，低通气指数及低氧血症明显改善，最低氧饱和度均＞７０％，Ｐ＜０．００１，低通气指数均＜７ｂ／ｈ，Ｐ＜０．０１。结论：夜间应用鼻面罩持续正压通气治疗中枢性低通气的初步结果示疗效显著。     

Nasopharyngeal symptoms in patients with obstructive sleep apnea syndrome. Effect of nasal CPAP treatment

BACKGROUND: Nasal side effects are often reported during nasal continuous positive airway pressure (CPAP) treatment of obstructive sleep apnea syndrome (OSAS) and may make the use of nasal CPAP difficult. OBJECTIVE: The aim of this study was to evaluate the effect of nasal CPAP on nasopharyngeal symptoms in OSAS patients. METHODS: The frequency and severity of nasopharyngeal symptoms and signs were prospectively evaluated in 49 consecutive OSAS patients (37 men, 12 women, mean (SD) age 54 (7) years, body mass index 35 (6) kg/m2) immediately before and after 6 months' treatment with nasal CPAP. RESULTS: Nasopharyngeal symptoms were common already before starting nasal CPAP: 74% of patients reported dryness, 53% sneezing, 51% mucus in the throat, 45% blocked nose, and 37% rhinorrhea. During nasal CPAP treatment, severity and frequency of sneezing (75%) and rhinorrhea (57%) increased. This increase was related to the season when nasal CPAP was applied, and was more profound in winter than in summer. Mild abnormalities on rhinoscopy and paranasal sinus X-rays were common both at baseline and at follow-up with no significant change during treatment. CONCLUSIONS: Nasopharyngeal problems were found to be frequent in patients with OSAS before nasal CPAP treatment, and tended to increase during the treatment.     

Effects of nasal high flow on nocturnal hypercapnia,sleep, and sympathovagal balance in patients with neuromuscular disorders

Sleep and Breathing - In neuromuscular disorders (NMD), inspiratory muscle weakness may cause sleep-related hypoventilation requiring non-invasive ventilation (NIV). Alternatively, nasal high flow...     

Prader-Willi syndrome with sleep disordered breathing: effect of two years nocturnal CPAP

We report a case of a 3-year-old child with Prader-Willi syndrome who had severe sleep disordered breathing with daytime hypersomnolence. His daytime blood gases showed type II respiratory failure. He was effectively treated with continuous positive airway pressure (CPAP) and has used this form of therapy for 2 years now with improvement in daytime somnolence, improved mental acuity and normalisation of daytime blood gases.     

阻塞性睡眠呼吸暂停综合征患者肺功能与夜间低氧血症的关系

目的探讨睡眠呼吸暂停综合征（ＳＡＳ）患者体位及肥胖因素引起的肺功能改变与夜间低氧血症的关系。方法选择确诊为ＳＡＳ患者３４例，分别于坐位和仰卧位检查肺功能和血气分析，整夜多导睡眠仪监测。肺功能、血气指标和理想体重％（ＩＢＷ％）分别与呼吸暂停指数（ＡＩ）、＜９０％Ｔ（ＳａＯ２低于９０％时间占总睡眠时间百分比）进行相关分析。结果患者由坐位改为仰卧位，ＰａＯ２、肺活量（ＶＣ％）、补呼气量（ＥＲＶ）、功能残气量（ＦＲＣ％）、残气容积（ＲＶ％）、肺总量（ＴＬＣ％）均出现有统计学意义的降低。ＡＩ与仰卧位ＶＣ％、ＴＬＣ％呈正相关。＜９０％Ｔ与坐位ＰａＯ２、ＥＲＶ呈负相关。ＩＢＷ％与坐、仰卧位ＶＣ％和ＥＲＶ呈负相关，与坐位ＦＲＣ呈负相关。ＩＢＷ％与＜９０％Ｔ呈正相关。结论伴有肥胖的ＯＳＡＳ患者，体位改变及肥胖因素影响患者肺功能，加重呼吸暂停时的低氧血症     

Transtracheal oxygen, nasal CPAP and nasal oxygen in five patients with obstructive sleep apnea.

The effect of transtracheal oxygen administration by means of a 9-French (2.7 mm) percutaneous catheter was assessed in five patients with severe obstructive sleep apnea. We hypothesized that the delivery of oxygen below the site of airway obstruction should reduce the arterial oxygen desaturation during apneas and hypopneas, thereby increasing respiratory stability. Standard sleep and respiratory measurements were recorded in these subjects with all-night polysomnography on nonconsecutive nights during four experimental conditions: room air (BL), nasal continuous positive airway pressure (CPAP), nasal O2 (NC O2), and transtracheal O2 (TT O2). In three of these subjects, room air was infused (TT RA) at flow rates comparable to TT O2. Compared with baseline room air measurements, TT O2 not only significantly increased the SaO2 nadir from 70.4 percent to 89.7 percent (p less than 0.01), but it also reduced the frequency of sleep apnea/hypopnea from 64.6 to 26.2/h sleep (p less than 0.01). NC O2 ameliorated desaturation during apnea/hypopnea (mean SaO2 nadir, 86.2 percent; p less than .01) but did not significantly alter frequency (59.0/h sleep). Nasal CPAP was the most effective means of reducing sleep apnea/hypopnea (13.8/h sleep) but did not abolish desaturations when apneas occurred (mean SaO2 nadir, 80.0 percent). Compared with oxygen, transtracheal infusion of room air appeared to be somewhat effective; however, the small number of studies with TT RA precluded statistical analysis. We believe that TT O2 is superior to NC O2 for some patients with obstructive sleep apnea because continuous oxygen flow below the site of airway obstruction more reliably prevents alveolar hypoxia and respiration is stabilized. Infusion of air or oxygen through the tracheal catheter flow may also increase mean airway pressure and reduce obstructive apnea similar to nasal CPAP. We conclude that TT O2 may be an effective alternative mode of therapy for some patients with severe sleep apnea/hypopnea when nasal CPAP is not tolerated or when combined oxygen and nasal CPAP are required.     

阻塞性睡眠呼吸暂停患者体质量指数与夜间低氧血症的关系

目的 探讨阻塞性睡眠呼吸暂停(obstructive sleep apnea,OSA)患者体质量指数(BMI)与夜间低氧血症的关系.方法 回顾性分析1 899例经多导睡眠图(PSG)检查确诊为OSA患者(年龄为21～80岁),根据OSA患者BMI分正常体质量组(18.5 kg/m2≤BMI≤24 kg/m2)、超重组( 24 kg/m2＜BMI≤28 kg/m2)和肥胖组(BMI＞28 kg/m2),分析OSA患者的BMI、年龄与血氧饱和度＜90％时间占总睡眠时间百分比(TS90％)的相关性,比较不同体质量组OSA患者的TS90％差异.结果 OSA患者夜间TS90％与BMI呈正相关(r=0.421,P＜0.05),与年龄呈负相关(r=-0.087,P＜0.05).在年龄和AHI相似的情况下,其TS90％随着BMI的增加而加重,正常体质量组、超重组和肥胖组TS90％分别为(9.3±12.5)％、(10.0±10.0)％和(13.8±14.4)％,三组间差异有统计学意义(F =13,330,P=0.000).结论 伴有肥胖的OSA患者将加重夜间的低氧血症.     

慢性阻塞性肺疾病稳定期夜间低氧的治疗进展

慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)稳定期患者常发生夜间低氧,特别是易发生在快动眼睡眠时相,持续夜间低氧会进一步发展为肺动脉高压、肺心病.为改善COPD稳定期夜间低氧,其治疗主要集中在长期氧疗、夜间无创正压通气、药物治疗,并取得了一定的疗效.本文对COPD稳定期夜间低氧的治疗进展作一综述.     

Sleepiness and nocturnal hypoxemia in Peruvian men with obstructive sleep apnea

Purpose

To evaluate the intensity of nocturnal hypoxemia associated with sleepiness in Peruvian men with a diagnosis of obstructive sleep apnea (OSA).

Methods

We carried out a secondary data analysis based on a study which includes patients with OSA who were seen in a private hospital in Lima, Peru from 2006 to 2012. We included male adults who had polysomnographic recordings and who answered the Epworth sleepiness scale (ESE). The intensity of nocturnal hypoxemia (oxygen saturation ≤90 %) was classified in four new categories: 0, <1, 1 to 10 and >10 % total sleep time with nocturnal hypoxemia (NH). When the ESE score was higher than 10, we used the definitions presence or absence of sleepiness. We used Poisson regression models with robust variance to estimate crude and adjusted prevalence ratios (PR) for association between sleepiness and NH.

Results

518 male patients with OSA were evaluated. Four hundred and fifty-two (87 %) patients had NH and 262 (51 %) had sleepiness. Of the 142 (27.4 %) patients who had >10 % total sleep time with NH, 98 (69.0 %) showed sleepiness and had a greater probability of sleepiness prevalence, with a crude PR of 1.82 (95 % CI 1.31–2.53). This association persisted in the multivariate models.

Conclusions

We found an association between NH and sleepiness. Only patients with the major intensity of NH (over 10 % of the total sleep time) had a greater probability of sleepiness. This suggests that sleepiness probably occurs after a chronic process and after overwhelming compensatory mechanisms.     

Reversal of central sleep apnea using nasal CPAP

Based on the theory that obstructive (OSA) and central (CSA) sleep apneas share common pathophysiologic mechanisms, we attempted to treat eight patients with predominantly CSA by continuous positive airway pressure (CPAP). All patients exhibited repetitive episodes of CSA and mixed sleep apneas (MSA) in the supine position with a mean duration of 23.7 +/- 0.7 s and 34.5 +/- 1.3 s, respectively. The pattern of apnea changed when the subject lay in the lateral position. Five patients were observed to develop OSA in the lateral position with a mean duration of 27.2 +/- 1.5 s, while the other three patients snored continuously. High levels of CPAP (range 9.0 to 16.5 cm H2O) prevented all CSA and MSA and resulted in quiet breathing in all eight patients. Intermediate levels of CPAP produced firstly MSA, then purely OSA and/or continuous snoring. Low levels of nasal CPAP also prevented OSA and snoring occurring in the lateral posture in all subjects (range 2.0 to 8.3 cm H2O). Three patients are currently on home CPAP therapy for a range of four to 36 months. We conclude that upper airway collapse in the supine posture has a key role in the induction of CSA. We suggest that a reflex inhibition of respiration through activation of supraglottic mucosal receptors during passive oropharyngeal airway closure caused CSA in these patients.     

Upper airway finding on CT scan with and without nasal CPAP in obstructive sleep apnea patients

The area of upper airway (from the nasopharynx to the hypopharynx) was measured by means of computed tomography (CT) scan in 15 confirmed cases of obstructive sleep apnea (OSA) and in 4 normal controls while they were awake. The minimum cross-sectional area (MA) of the upper airway was 14.7 +/- 20.0 mm2 in OSA patients and 80.0 +/- 33.1 mm2 in normal controls and the difference was statistically significant (p less than 0.01). In OSA patients, MA did not correlate with age, body weight, apnea index, desaturation index, mean nadir-SO2 and lowest SO2. MA was also measured with OSA patients while nasal continuous positive airway pressure (NCPAP) of 10 cmH2O was applied and it was found that MA was significantly widened when NCPAP therapy was performed. We conclude that upper airway narrowing is consistent finding in OSA patients but the degree of narrowing does not correlate with parameters of apnea and gas exchange during sleep, and NCPAP is effective to widen the area of upper airway in OSA patients.     

Objective measurement of compliance with nasal CPAP treatment for obstructive sleep apnoea syndrome

Compliance with nasal continuous positive airway pressure (CPAP) has become a major concern, since this treatment is efficacious, but constraining. In 46 consecutive obstructive sleep apnoea (OSA) patients, we measured compliance with nasal CPAP by establishing a mean rate of use, with a built-in time counter read at three-month intervals, over a mean follow-up period of 232 +/- 27 days. The mean rate of use in the whole group was 5.14 +/- 0.31 hours per day. The acceptance rate was 90.9-93.2%, showing that patient acceptance is not a limitation in the use of nasal CPAP.     

Leptin and ghrelin levels in patients with obstructive sleep apnoea: effect of CPAP treatment.

Serum leptin and ghrelin levels were investigated in patients with obstructive sleep apnoea (OSA) syndrome before and during continuous positive airways pressure (CPAP) treatment and compared with body mass index (BMI)-matched controls without OSA. Male patients (n=30) with OSA (apnoea/hypopnoea index=58+/-16, BMI=32.6+/-5.3 kg x m(-2)) underwent CPAP treatment. Fasting leptin and ghrelin were measured at baseline and 2 days, and in the case of leptin 2 months after initiation of treatment. Baseline plasma ghrelin levels were significantly higher in OSA patients than in controls. After 2 days of CPAP treatment, plasma ghrelin decreased in almost all OSA patients (n=9) to levels that were only slightly higher than those of controls (n=9). Leptin levels did not change significantly from baseline after 2 days of CPAP treatment, but were higher than in the control group. After 8 weeks, leptin levels decreased significantly, although the BMI of the patients showed no change. The decrease in leptin levels was more pronounced in patients with a BMI <30 kg x m(-2). These data indicate that the elevated leptin and ghrelin levels are not determined by obesity alone, since they rapidly decreased during continuous positive airways pressure therapy.     

Normal and elevated HbA1C levels correlate with severity of hypoxemia in patients with obstructive sleep apnea and decrease following CPAP treatment

Purpose  

Sleep apnea is associated with higher HbA1C levels in patients with and without diabetes but whether its severity correlates with HbA1C levels ranging from normal to abnormal is less clear. Also, the effect of continuous positive airway pressure (CPAP) treatment on HbA1C levels in patients with sleep apnea is controversial.     

正压通气对阻塞性睡眠呼吸暂停综合征夜间室性心律失常的作用

目的 探讨阻塞性睡眠呼吸暂停综合征(OSAS)严重程度与夜间室性心律失常间的关系以及经鼻持续气道正压通气(nCPAP)对室性心律失常的作用.方法 197例OSAS者按呼吸紊乱指数分轻、中、重3组,观察夜间室性心律失常发生率,比较组间差异性,并观察各组行nCPAP前后宣性心律失常发生率的变化.结果 OSAS者夜间室性心律失常发生率随着病情加重而明显增加、室性心律失常增多.治疗后各组夜间室性心律失常发生率较治疗前显著下降.结论 随着OSAS者病情加重,夜间室性心律失常发生率增多,nCPAP能有效降低OSAS者夜间室性心律失常发生率.