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991.
目的探讨PHP动作对载人离心机致加速度性肺不张的防护作用。方法试验采用的模拟空战曲线(SACM)包括2个各45 s的+4.5 Gz和2个分别为15 s和45 s的+5.0 Gz的平台,基线为+3.0 Gz(各30 s)。7名志愿者呼吸浓度为100%的O2,在3种条件下进行SACM离心机暴露:A组,O2系统安全余压打开;B组,O2系统安全余压关闭;C组,O2系统安全余压关闭且采用PHP动作。结果 SACM暴露后,A组肺活量(VC)下降0.27 L,用力肺活量(FVC)和用力呼气量(FEV)均无显著变化,主观症状评分较低(2.5±2.6),胸部X线成像改变不明显。B组VC和FVC分别下降0.69 L(P<0.01)和0.29 L(P<0.05),咳嗽、胸痛、吸气困难等主观症状明显,其评分(8.1±2.2)显著高于有安全余压时(P<0.05),出现肺不张的典型影像学表现。C组VC和FVC无明显下降,无明显主观症状,主观感觉评分很低(0.8±0.9),与不采用PHP动作时的差异非常显著(P<0.01),肺不张的影像学征象比不采用PHP动作时明显减轻。结论采用PHP动作能够有效防止加速度性肺不张的发生。 相似文献
992.
产时抚触配合拉玛泽呼吸法对分娩的影响观察 总被引:3,自引:0,他引:3
目的探讨产时抚触配合拉玛泽呼吸法对产妇分娩的影响。方法选择在门诊产前检查中接受过拉玛泽呼吸法训练,并在产时给予抚触的80例产妇作为观察组,同时选择未在门诊接受拉玛泽呼吸法训练,且产时未给予抚触的80例产妇作为对照组,对比分析两组的产程平均时间、分娩时对疼痛的耐受程度、分娩结局等指标。结果观察组的产程平均时间小于对照组,观察组对分娩时疼痛的耐受程度更好、阴道分娩率更高,与对照组比较差异有显著意义(P〈0.05)。结论产时抚触配合拉玛泽呼吸法能有效缩短产程、降低分娩痛苦、提高阴道分娩率。 相似文献
993.
《Sleep medicine》2021
BackgroundObstructive sleep apnea (OSA) is prevalent in older adults but still underdiagnosed for many reasons, such as underreported symptoms, non-specific ones because of the comorbidities and polypharmacy, or the social belief of sleep problems as normal with aging.ObjectivesTo identify salient symptoms and comorbidities associated with OSA, diagnosed by nocturnal respiratory polygraphy in geriatric inpatients.MethodWe conducted a retrospective, cross-sectional study in a sample of 102 geriatric inpatients from a French Geriatric University Hospital. We reviewed medical records to collect demographic, medical information including comorbidities, the geriatric cumulative illness rating scale (CIRS-G), subjective sleep-related symptoms and data of overnight level three portable sleep polygraphy recording.ResultsAmong classic OSA symptoms, only excessive daytime sleepiness (p = 0.02) and nocturnal choking (p = 0.03) were more prevalent in older inpatients with OSA (n = 64) than in those without (n = 38). The prevalence of comorbidities and mean CIRS-G scores were not different between groups except for the lower prevalence of chronic obstructive pulmonary disease and the higher level of creatinine clearance in OSA patients. Multivariate analysis showed OSA was associated with excessive daytime sleepiness (OR = 2.83, p = 0.02) in symptoms-related model and with composite CIRS-G score (OR 1.26, p = 0.04) in comorbidities-related model.ConclusionsOnly excessive daytime sleepiness and comorbidity severity (composite CIRS-G score) were associated with the objective diagnosis of OSA, while other usual clinical OSA symptoms and comorbidities in geriatric inpatients were not. These findings emphasize the importance of excessive daytime sleepiness symptom, when reported in comorbid older patients, strongly suggesting OSA and requiring adequate nocturnal exploration. 相似文献
994.
995.
996.
Bradley A. Edwards Scott A. Sands Philip J. Berger 《Respiratory physiology & neurobiology》2013,185(1):144-155
Any general model of respiratory control must explain a puzzling array of breathing patterns that are observed during the course of a lifetime. Particular challenges are to understand why periodic breathing is rarely seen in the first few days after birth, reaches a peak at 2–4 weeks postnatal age, and disappears by 6 months, why it is prevalent in preterm infants, and why it reappears in adults at altitude or with heart failure. In this review we use the concept of loop gain to obtain quantitative insight into the genesis of unstable breathing patterns with a particular focus on how changes in carotid body function could underlie the age-related dependence of periodic breathing. 相似文献
997.
Sleep disorders in multiple sclerosis (MS) are more common than in general population and are considered to be one of the important etiological factors in development of fatigue, most common and debilitating symptom of MS. Although almost all of the major subgroups of sleep disorders such as insomnia, sleep disordered breathing, REM sleep behavior disorder, narcolepsy and restless legs syndrome have been described in the MS patients their higher prevalence in MS population than in healthy controls in some of the sleep disorders is not fully elucidated. Immunological background in disease development in both multiple sclerosis and sleep disorders have been proposed as possible common pathophysiological mechanism and recent findings of disrupted melatonin pathways in MS patients suggest multi-level causative mechanism of the development of sleep disorders in MS. 相似文献
998.
《Sleep medicine》2013,14(12):1310-1316
BackgroundObstructive sleep apnea (OSA) is associated with autonomic dysfunction in adults and school-aged children; however, this association has not been investigated in preschool children. We aimed to analyze heart rate variability (HRV) and catecholamine levels in preschool children with OSA.MethodsOne hundred and forty-two snoring children aged 3–5 years and 38 nonsnoring control group children underwent overnight polysomnography (PSG). Nocturnal urinary catecholamines were measured in 120 children. Children were grouped according to their obstructive apnea–hypopnea index (OAHI) (control [no snoring], OAHI ⩽ 1 event/h; primary snoring, OAHI ⩽ 1 event/h; mild OSA OAHI > 1 ⩽ 5 events/h; moderate to severe [MS] OSA, OAHI > 5 events/h). The HRV parameters for each child were averaged during rapid eye movement (REM) and non-REM (NREM) sleep.ResultsDuring stable sleep, low-frequency (LF) HRV was similar between groups. High-frequency (HF) HRV was higher in the MS OSA group compared with the control group during all sleep stages (NREM sleep stages 1 and 2 [NREM1/2], 4234 ± 523 ms2 vs 2604 ± 457 ms2; NREM sleep stages 3 and 4 [NREM3/4], 4152 ± 741 ms2 vs 3035 ± 647 ms2; REM, 1836 ± 255 ms2 vs 1456 ± 292 ms2; P < .01 for all). The LF/HF ratio was lower in the MS OSA group compared with the control group (NREM1/2, 0.4 ± 0.06 vs 0.7 ± 0.05; NREM3/4, 0.3 ± 0.06 vs 0.4 ± 0.05; REM, 0.8 ± 0.1 vs 1.3 ± 0.1; P < .01 for all). Catecholamine levels were not different between groups.ConclusionsIn preschool children, OSA is associated with altered HRV, largely due to the HF fluctuations in heart rate (HR) which occur during respiratory events and are still evident during stable sleep. The preschool age may represent a window of opportunity for treatment of OSA before the onset of the severe autonomic dysfunction associated with OSA in adults and older children. 相似文献
999.
Gisèle Maury Frédéric Senny Laurent Cambron Adelin Albert Laurence Seidel Robert Poirrier 《Journal of sleep research》2014,23(6):709-716
The mandible movement (MM) signal provides information on mandible activity. It can be read visually to assess sleep–wake state and respiratory events. This study aimed to assess (1) the training of independent scorers to recognize the signal specificities; (2) intrascorer reproducibility and (3) interscorer variability. MM was collected in the mid‐sagittal plane of the face of 40 patients. The typical MM was extracted and classified into seven distinct pattern classes: active wakefulness (AW), quiet wakefulness or quiet sleep (QW/S), sleep snoring (SS), sleep obstructive events (OAH), sleep mixed apnea (MA), respiratory related arousal (RERA) and sleep central events (CAH). Four scorers were trained; their diagnostic capacities were assessed on two reading sessions. The intra‐ and interscorer agreements were assessed using Cohen's κ. Intrascorer reproducibility for the two sessions ranged from 0.68 [95% confidence interval (CI): 0.59–0.77] to 0.88 (95% CI: 0.82–0.94), while the between‐scorer agreement amounted to 0.68 (95% CI: 0.65–0.71) and 0.74 (95% CI: 0.72–0.77), respectively. The overall accuracy of the scorers was 75.2% (range: 72.4–80.7%). CAH MMs were the most difficult to discern (overall accuracy 65.6%). For the two sessions, the recognition rate of abnormal respiratory events (OAH, CAH, MA and RERA) was excellent: the interscorer mean agreement was 90.7% (Cohen's κ: 0.83; 95% CI: 0.79–0.88). The discrimination of OAH, CAH, MA characteristics was good, with an interscorer agreement of 80.8% (Cohen's κ: 0.65; 95% CI: 0.62–0.68). Visual analysis of isolated MMs can successfully diagnose sleep–wake state, normal and abnormal respiration and recognize the presence of respiratory effort. 相似文献
1000.
《Journal of the American Dental Association (1939)》2014,145(2):165-178
BackgroundThe reference standard for the diagnosis of pediatric sleep-disorder breathing (SDB) is a full polysomnography (PSG) (an overnight sleep study). There are many obstacles to children being able to undergo a full PSG; therefore, the authors evaluated the diagnostic value of alternative diagnostic methods (clinical history and physical examination) for pediatric SDB.Types of Studies ReviewedThe authors selected articles in which the investigators' primary objective was to evaluate the diagnostic capability of physical evaluations and questionnaires compared with the current reference standard (that is, a full PSG) to diagnose SDB in children younger than 18 years. The authors searched several electronic databases without limitations.ResultsUsing a two-step selection process, the authors identified 24 articles and used them to conduct a qualitative analysis. They conducted a meta-analysis on 11 of these articles. Among these articles, only one involved a test that had diagnostic accuracy good enough to warrant its use as a screening method for pediatric SDB, but its diagnostic accuracy was not sufficient to be considered a true diagnostic tool (that is, a replacement for full PSG) for pediatric SDB.Practical ImplicationsThe involvement of dentists in the screening process for pediatric SDB can contribute significantly to children's health. The identified questionnaire could be considered an acceptable screening test to determine which children to refer to a sleep medicine specialist. 相似文献