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91.
SUMMARY  Arterial blood pressure is influenced by sleep-related breathing disorders. As cardiovascular consequences can be diagnosed by an accurate recording and analysis of blood pressure, new recording methodologies and an approach to analysis are presented here. Invasive continuous blood pressure recording is the common reference for all methodologies. As blood pressure varies rapidly in parallel with sleep-related breathing disorders it is indispensible to record blood pressure continuously. To introduce non-invasive methodology the Finapres system was used during sleep studies; a validation study showed severe limitations. This study was followed by the validation of an improved system called Portapres, which is portable, has two finger cuffs and a hydrostatic height compensation.
Analysis of continuous blood pressure in patients with sleep apnoea is carried out to detect mechanisms which influence the cardiovascular risk. Spectrum analysis of systolic blood pressure showed two different major oscillations present in patients with obstructive sleep apnoea. One oscillation (<0.06 Hz) occurs in parallel with each apnoeic episode and the other oscillation (0.2-0.4 Hz) occurs in parallel with the obstructive efforts during each apnoea and in parallel with respiration during periods of snoring. These two oscillations were so specific that the use of non-invasive continuous blood pressure recording allowed an estimation of the extent of underlying breathing disorders, and assessment of cardiovascular risk in a patient with obstructive apnoea in terms of hypertension and on the basis of ambulatory monitoring.  相似文献   
92.
To investigate airway physiology by use of inhaled aerosols, it is frequently necessary to measure the actual amount of material deposited on the airway wall as well as the site of particle deposition. To satisfy these needs, radiolabeled aerosols and gamma camera techniques have been used to measure regional deposition of inhaled particles. To make quantitative measurements of the amount deposited, previous investigators have used a "phantom" technique to indirectly calibrate the gamma camera for the attenuation of gamma rays through the lungs and chest wall. For this calibration, the phantom is a simulated lung containing a known amount of radioactivity. Radioactive counts emitted from the phantom are assumed to be attenuated in the same manner as the intact human lung. The present article describes a technique to determine directly the amount of inhaled aerosol deposited in the lung and simultaneously to calibrate the gamma camera for each individual subject. We used right angle light scattering and a gamma camera to measure individual values of the deposition fraction (DF) of inhaled aerosol deposited in the lung and the coefficient of attenuation (AC) of gamma rays in normal and obstructed lungs of human subjects. Radiolabeled monodisperse aerosols 1 and 2 microns in diameter were used. Knowledge of the activity of the inhaled aerosol (microcurie per liter), the volume inhaled, and the measured DF determined each subject's AC (counts per minute per microcurie). DF varied by an order of magnitude in normal (0.04 to 0.48) and obstructed (0.16 to 0.75) of subjects.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
93.
Summary A randomized, placebo-controlled, double-blind crossover investigation in 12 patients with non-asthmatic chronic obstructive lung disease and co-existing stable angina pectoris was done to compare two 1-selective adrenoceptor blocking agents, atenolol 100 mg and bisoprolol 20 mg. Systolic and diastolic blood pressures (SBP, DBP), heart rate (HR) as well as airway resistance (AWR, and less frequently forced expiratory volume in 1 s (FEV1) and intrathoracic gas volume (ITGV) were measured in the sitting position before and at various times up to 24 h after drug intake.During the first 4 h both beta-blockers produced a significant reduction in HR in comparison to placebo (p<0.01). Atenolol 100 mg significantly increased AWR relative to placebo and bisoprolol (p<0.05). After 24 h, a significant reduction in HR (p<0.01) could only be demonstrated after bisoprolol, whereas atenolol alone led to a significant elevation in AWR relative to placebo and bisoprolol (p<0.05) at that time.It is concluded that bisoprolol appears to have a high degree of beta1-selectivity, thus providing a wide split between beta1- and beta2-adrenoceptor blockade. Bisoprolol in its therapeutic dose range is expected to be relatively safe as regards bronchoconstriction in patients suffering both from hypertension and/or angina pectoris and chronic obstructive lung disease.  相似文献   
94.
目的:探究泽漆水提物对香烟烟雾(CS)所致的慢性阻塞性肺病(COPD)的保护作用及肺组织癌前病变相关蛋白的影响。方法:通过建立CS所致的COPD小鼠模型(60只),随机分为正常组、模型组、阳性药组(地塞米松2 mg·kg-1)及泽漆水提物低、中、高剂量组(1.875、3.75、7.5 g·kg-1)。采用高效液相色谱法(HPLC)测定泽漆水提物中相关成分;动物肺功能仪检测小鼠呼气末期暂停(EEP)、气道阻力(Penh)、50%肺活量呼吸时的呼气流量(EF50)等肺功能指标变化;高通量液相蛋白芯片技术检测小鼠肺泡灌洗液(BALF)中白细胞介素(IL)-2、IL-5、IL-18、IL-17A、IL-27等炎性因子水平变化;苏木素-伊红(HE)染色检测小鼠肺组织的病理变化;比色法测定小鼠肺组织中的丙二醛(MDA)、髓过氧化物酶(MPO)及谷胱甘肽过氧化物酶(GSH-Px)含量变化;实时荧光定量聚合酶链式反应(Real-time PCR)检测肿瘤坏死因子-α(TNF-α)、转化生长因子-β(TGF-β)、基质金属蛋白酶(MMP)-2、MMP-9及MM...  相似文献   
95.
96.
Increasing epidemiological evidence suggests that optimal diet quality helps to improve preservation of lung function and to reduce chronic obstructive pulmonary disease (COPD) risk, but no study has investigated the association of food insecurity (FI) and lung health in the general population. Using data from a representative sample of US adults who participated in the National Health and Nutrition Examination Survey (NHANES) 2007–2012 cycles, we investigated the association between FI with lung function and spirometrically defined COPD in 12,469 individuals aged ≥ 18 years of age. FI (high vs. low) was defined using the US Department of Agriculture’s Food Security Scale). Population-weighted adjusted regression models were used to investigate associations between FI, and forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), their ratio, and spirometrically defined restriction (FVC below the lower limit of normal) and airflow obstruction (COPD). The prevalence of household FI was 13.2%. High household FI was associated with lower FVC (adjusted β-coefficient −70.9 mL, 95% CI −116.6, −25.3), and with higher odds (OR) of spirometric restriction (1.02, 95% CI 1.00, 1.03). Stratified analyses showed similar effect sizes within specific ethnic groups. High FI was associated with worse lung health in a nationally representative sample of adults in the US.  相似文献   
97.
目的:评价莫达非尼联合双水平气道正压通气(BiPAP)在治疗慢性阻塞性肺疾病(COPD)合并睡眠呼吸暂停综合征(OSAS)的临床疗效。方法:选取在医院接受治疗的93例COPD合并OSAS患者,根据治疗方案的不同将其分为对照组(41例)和观察组(52例),对照组采用常规药物联合BiPAP治疗;观察组在对照组的基础上口服莫达非尼。记录两组正压通气时间及不良反应情况,比较两组治疗前后血氧分压(PaO2)、血二氧化碳分压(PaCO2)、用力肺活量(FVC)、第1秒用力呼气容积(FEV1)、FEV1与FVC的比值(FEV1/FVC)、呼吸暂停指数(AHI)、总睡眠时间、最低氧饱和度和Epworth睡眠量表(ESS)评分的改善情况。结果:对照组和观察组患者治疗后的AHI、总睡眠时间、最低氧饱和度及ESS评分均较治疗前有显著改善,差异有统计学意义(t对照组=21.187,t=6.155,t=7.648,t=29.947;t观察组=22.380,t=7.931,t=8.168,t=37.593;P<0.05),观察组患者总睡眠时间及ESS评分均显著低于对照组,差异有统计学意义(t=2.315,t=14.232;P<0.05)。对照组和观察组患者治疗后1周和4周与治疗前相比,PaO2有显著升高,Pa CO2则有明显降低,差异有统计学意义(F对照组=29.947,F=36.147;F观察组=27.533,F=34.580;P<0.05),而两组比较差异无统计学意义。对照组和观察组患者治疗后1周和4周的FVC、FEV1及FEV1/FVC通气指标均较治疗前有显著改善(F对照组=16.506,F=40.570,F=59.220;F观察组=19.680,F=43.962,F=61.728;P<0.05),而两组比较差异无统计学意义。观察组和对照组不良反应发生率分别为19.2%(10/52)和7.3%(3/41),而两组比较差异无统计学意义。结论:对于COPD合并OSAS患者,呼吸机BiPAP模式可显著改善肺功能及肺通气相关指标,莫达非尼能提升睡眠质量,减轻白天的嗜睡症状,且未出现明显不良反应。  相似文献   
98.
目的:观察慢阻肺合并肺动脉高压患者机体炎性反应指标及与肺阻力相关指标表达,分析患者炎性反应与肺阻力的相关性。方法:回顾性选取医院收治的116例慢阻肺患者病历资料,根据患者是否合并肺动脉高压将其分为非肺动脉高压组(59例)和肺动脉高压组(57例)。抽取两组患者清晨空腹静脉血,检测炎性反应指标中的C反应蛋白(CRP)、白细胞计数(WBC)、降钙素原(PCT)、白细胞介素-6(IL-6)以及血沉(ESR),并进行对比;检测两组患者肺阻力指标振荡频率5 Hz下的气道粘性阻力实测值占预计值的百分比[R_5占预计值(%)]、振荡频率5 Hz与共振频率(Fres)之间电抗X曲线下面积(AX),振荡频率在5 Hz的肺弹性阻力(X5),并进行对比。分析炎性反应相关指标与肺阻力指标的相关性。结果:肺动脉高压组CRP、WBC、PCT及IL-6水平均高于非肺动脉高压组,ESR低于非肺动脉高压组,差异有统计学意义(t=16.243,t=12.413,t=6.726,t=32.670,t=10.102;P<0.05);肺动脉高压组R5占预计值(%)、AX及X5均高于非肺动脉高压组,差异有统计学意义(t=19.770,t=8.230,t=19.685;P<0.05);相关检验结果显示,慢阻肺合并肺动脉高压患者CRP、WBC、PCT及IL-6水平与R_5占预计值%、AX及X5值呈正相关,ESR水平与R_5占预计值%、AX及X5值呈负相关。结论:慢阻肺合并肺动脉高压患者常伴不同程度的炎性反应与肺阻力,且炎性反应程度与患者肺阻力间呈明显相关性,炎性因子检测可能对评估慢阻肺合并肺动脉高压患者的肺阻力情况有一定价值,可指导临床诊治。  相似文献   
99.
目的:探究无创正压通气治疗慢性阻塞性肺疾病急性加重期合并重症呼吸衰竭的临床效果。方法:以2018年7月~2019年6月作为研究时段,选择此期间本院收治的慢性阻塞性肺疾病急性加重期合并重症呼吸衰竭患者,共78例,按照入院先后顺序编号,前39例设定为对照组,给予常规治疗,后39例设定为观察组,在对照组基础上进行无创正压通气治疗,比较两组治疗效果和血气指标变化情况。结果:观察组总有效率为94.87%,高于对照组76.92%,P<0.05;两组治疗前PaO2、PaCO2、SaO2组间比较,差异无统计学意义,P>0.05,治疗后PaCO2较治疗前降低,PaO2、SaO2较治疗前升高,P<0.05,组间比较观察组变化幅度更大,P<0.05。结论:无创正压通气治疗慢性阻塞性肺疾病急性加重期合并重症呼吸衰竭的临床效果显著,可有效改善血气指标,值得临床借鉴。  相似文献   
100.
目的:探讨慢性阻塞性肺疾病(COPD)呼吸机依赖患者膈肌起搏器的应用及疗效。方法:把2018年6月~2019年6月本院呼吸内科收治的COPD使用呼吸机并发生依赖的清醒患者60例作为研究对象,男27例,女33例;患者年龄60~75岁,平均(66.3±1.2)岁,随机分为观察组(运用常规治疗及护理并增加使用膈肌起搏器)和对照组(运用常规治疗及护理),每组30例,对两组脱机成功率和脱机时间进行比较。结果:观察组患者脱机情况明显优于对照组,观察组与对照组2周脱机成功率分别为83.3%和46.7%,脱机时间分别为(7.56±1.45),(9.42±1.28)d,差异均有统计学意义(P<0.05)。结论:COPD呼吸机依赖患者准备脱机前,给予膈肌起搏器治疗,可明显提高脱机成功率及缩短呼吸机使用时间。  相似文献   
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