Nocturnal hypoxemia in patients with chronic obstructive pulmonary disease.

Marked hypoxemia occurs during REM sleep in patients with chronic obstructive pulmonary disorder. This article deals with the mechanisms, pathophysiologic consequences, and treatment of REM hypoxemia.     

Bronchopulmonary infection due to Branhamella catarrhalis in patients with obstructive lung disease

During the period from February 1988 to April 1990, 214 sputum samples from COPD patients with bronchopulmonary infection were quantitatively cultured. 17 strains were identified as Branhamella catarrhalis, being present in 7.9% of all sputum cultures and 11.0% of those positive for a pathogen (Quantity = 10(10)/L of Isolated Organism). Half of B. catarrhalis infection was isolated in mixed with other pathogens. Haemophilus influenza was the most frequently associated pathogen. The second was H. influenza plus Streptococcus pneumoniae. Of 17 B. catarrhalis, 2 strains were positive for beta-lactamase. The incidence of B. catarrhalis infection varied with the seasons, being prevalent in late winter and early spring. Many factors contributed to the pathogenicity of B. catarrhalis, such as the rapid increase of positive beta-lactamase strains and the change of seasons. The result showed that B. catarrhalis was the fourth frequent pathogen in COPD patients accompanied with bronchopulmonary infection. Most of the strains were resistant to penicillin, and beta-lactamase strains were discovered. Therefore, B. catarrhalis should be as a potential pathogen to be identified in sputum. A suitable method was recommended to identified B. catarrhalis.     

慢性阻塞性肺疾病患者夜间缺氧与肺功能损减的关系

目的分析慢性阻塞性肺疾病（COPD）患者肺功能受损与夜间低氧缺氧的关系。方法对排除了睡眠呼吸暂停低通气综合征的160例稳定期COPD患者进行夜间脉搏氧饱和度监测和肺功能检测。进行年龄及体质量指数匹配后,按COPD肺功能分级将患者分为3组：轻度缺氧、中度缺氧、重度缺氧组。比较各组间夜间缺氧的严重程度。结果各组间在夜间平均血氧饱和度血氧饱和度低于90％时间占总睡眠时间百分比、夜间平均脉搏、每小时脉搏上升6次的次数等方面差异有显著性（P〈0．01）。而且肺活量占预计值百分比、1秒钟用力呼气容积占预计值百分比、残气容积、残气容积与肺总量比值差异亦有显著性（P〈0．05）。结论COPD患者夜问缺氧的严重程度与肺功能受损的程度明显相关,这可能会影响患者的心血管系统。     

慢性阻塞性肺疾病患者睡眠时低氧血症的发生和预测

目的 研究慢性阻塞性肺疾病（ＣＯＰＤ）患睡眠时低氧血症的发生与否及机制。方法对３０例ＣＯＰＤ患白天肺功能、动脉血气及夜间血氧水平与正常对照组（８名）进行比较和分析。结果 ＣＯＰＤ患睡眠时血氧水平较正常人明显下降（Ｐ〈０．０５），尤以快动眼睡眠期（ＲＥＭ期）显，无论夜间平均血氧饱和度（ＭＳａＯ２）还是夜间最低血氧饱和度（ＭｍＳａＯ２），下降程度均明显高于正常人（Ｐ〈０．０５）。从血氧分布情况     

Renin-angiotensin II-aldosterone and ACTH-cortisol control during acute hypoxemia and exercise in patients with chronic obstructive pulmonary disease

Acute hypoxia has been reported to induce a decrease in aldosterone levels despite no change or increases in plasma renin activity and ACTH. Converting enzyme inhibition and/or mild hypokalemia have been suggested as possible mechanisms for this dissociation. We studied 15 patients with chronic obstructive pulmonary disease (COPD) who used continuous ambulatory O2 therapy (home O2). Group A (n = 10) had O2 discontinued for 30 min before exercise to induce hypoxemia; Group B (n = 5) had O2 continued for 30 min (time control). Discontinuation of home O2 in Group A resulted in a significant fall in Pao2 from 77 +/- 6 to 51 +/- 2 torr. Arterial CO2 tension decreased and the pHa increased slightly. Renin, angiotensin II, plasma potassium, and sodium did not change during hypoxemia, whereas ACTH increased significantly. Despite this, aldosterone decreased from 26 +/- 5 to 18 +/- 2 ng/dl. Group B (time control) did not exhibit significant changes in hormones over 30 min, indicating that the effects observed in Group A were specific to O2 discontinuation. Exercise in Group A induced significant increases in ACTH, potassium, and aldosterone. We conclude from these data that acute hypoxemia in patients with COPD results in a decrease in aldosterone not related to converting enzyme inhibition, ACTH, or plasma potassium.     

Almitrine bismesylate in chronic obstructive lung disease and persistent hypoxemia. Controlled double-blind study with oral administration

Almitrine bismesylate has been shown to be a respiratory stimulating substance which acts primarily via the peripheral chemoreceptors. The effect of the oral administration of Almitrine (200 mg/day for 9 days) was investigated in a controlled double-blind study with 18 patients suffering from chronic obstructive lung disease and hypoxemia (PaO2 less than 60 mm Hg). During the therapy with Almitrine an early and lasting improvement in the PaO2 and PaCO2 could be obtained. This improvement was significant compared with the placebo group. On the last day of treatment with Almitrine the PaO2 increased by 16.2 mm Hg (p less than 0.001) and the PaCO2 decreased by 7.3 mm Hg (p less than 0.01). Simultaneously, an increase in minute ventilation (5.24 liters on day 9) could be observed. This increase was not significant compared with the placebo group. There was a correlation of -0.61 between the changes in minute ventilation and in PaCO2. The lung functional parameters vital capacity (VC), forced expiratory volume in 1 s (FEV1) and peak expiratory flow (PEF) increased on several days in both groups; a change in Rtot was observed in the treatment group only. A reduction of dyspnea also was observed in both groups. In addition to the ventilatory stimulant action on the peripheral chemoreceptors, the changes in blood gases induced by Almitrine also should be discussed as an improvement of the ventilation/perfusion ratio. In this therapeutical trial no side effects during the therapy with Almitrine have been observed.     

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     

Relationships of carbon dioxide retention to ventilatory impairment and hypoxemia in chronic obstructive lung disease

In a group of 80 male patients (average age 52.5 years) with severe obstructive ventilatory impairment (FEV1.0 less than 40% of predicted) due to chronic bronchitis and/or emphysema, the blood carbon dioxide tension measured at rest, in a stable clinical status, was confronted to the spirometric variables and the oxygen tension. PaCO2 (range 31--60 mm Hg) was loosely related to the VC (r = -0.28) and the FEV (r = -0.30, both p less than 0.05) and strongly related to the PaO2 (r = 0.60; p less than 0.001). When patients were classified as bronchitic or emphysematous according to clinical, roentgenologic and biological criteria, the correlations above were found to be higher for bronchitics. In patients with chronic bronchitis with severe obstruction a very good estimation of PaCO2 is possible from PaO2: PaCO2 = 75.8-0.44 PaO2 (SEE 0.4 MM Hg).     

Air travel hypoxemia with chronic obstructive pulmonary disease

Because persons with chronic obstructive pulmonary disease and mild hypoxemia may develop severe hypoxemia during commercial airline flights, we measured arterial blood gas pressures in 13 such patients during a flight in an unpressurized airplane (cabin pressures typical of commercial air travel). At 1650 m, mean arterial Po2 decreased from 68.2 +/- 8.5 (SD) mm Hg to 51 +/- 9.1 mm Hg, and mean arterial Pco2, from 40.9 +/- 0.9 to 37.1 +/- 6.4 mm Hg. At 2250 m, mean arterial Po2 and Pco2 were 44.7 +/- 8.7 and 36.5 +/- 5.8 mm Hg, respectively. No symptoms attributable to hypoxemia occurred. Arterial Po2 measured in patients while breathing room air several weeks before the flight did not correlate with that measured at 1650 m, but arterial Po2 measured less than 2 hours before the flight in room air or a 17.2% oxygen mixture did. Whether a patient will need supplemental oxygen to maintain arterial Po2 above a given value can be predicted from arterial blood samples taken while the patient is breathing a hypoxic gas mixture or room air within 2 hours of the flight.     

Effect of hypoxemia on sodium and water excretion in chronic obstructive lung disease

To determine the role of hypoxemia in the pathogenesis of impaired sodium and water excretion in advanced chronic obstructive lung disease, 11 clinically stable, hypercapneic patients requiring long-term supplemental oxygen were studied. The renal, hormonal, and cardiovascular responses to sodium and water loading were determined during five-and-a-half-hour studies on a control day (arterial oxygen tension = 80 +/- 6 mm Hg) and on an experimental day under hypoxic conditions (arterial oxygen tension = 39 +/- 2 mm Hg). Hypoxemia produced a significant decrease in urinary sodium excretion but did not affect urinary water excretion. Hypoxemia also resulted in concomitant declines in mean blood pressure, glomerular filtration rate, and filtered sodium load. Renal plasma flow and filtration fraction were unchanged whereas cardiac index rose. On the control day, plasma renin activity and norepinephrine levels were elevated whereas aldosterone and arginine vasopressin levels were normal; none of these four hormones was affected by hypoxemia. Renal tubular function did not appear to be altered by hypoxemia as there was no significant change in fractional reabsorption of sodium. The concurrent decreases in glomerular filtration rate, filtered sodium load, and mean blood pressure at constant renal plasma flow suggest that the reduction in urinary sodium excretion was due to an effect of hypoxemia on glomerular function, possibly related to impaired renovascular autoregulation.     

慢性阻塞性肺疾病的睡眠相关低氧

慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)患者的夜间低氧问题从50年以前就认识到了.在许多COPD患者的多导睡眠监测研究中,研究者发现患者的睡眠潜伏期延长,总睡眠时间减少.慢波睡眠减少,快速动眼睡眠减少,还有一个最为重要的问题就是睡眠相关低氧(SRH).本文主要对COPD患者SRH的定义、原因、患病率、严重程度、意义以及治疗等相关问题作一综述.     

Chronic obstructive pulmonary disease and interstitial lung disease in patients with lung cancer

Background and objective:   Although lung cancer is frequently accompanied by COPD and interstitial lung disease (ILD), the precise coincidence of these diseases with lung cancer is not well understood. The objectives of this study were to determine the prevalence of abnormal CT and spirometric findings suggestive of COPD or ILD in a population of patients with untreated lung cancer, and to estimate the lung cancer risk in this population.
Methods:   The study population consisted of 256 patients with untreated lung cancer and 947 subjects participating in a CT screening programme for lung cancer. Semi-quantitative analysis of low attenuation area (LAA), fibrosis and ground glass attenuation (GGA) on CT was performed by scoring. Gender- and age-matched subpopulations, with stratification by smoking status, were compared using the Mantel–Haenszel projection method.
Results:   Inter-observer consistency was excellent for LAA, but not as good for fibrosis or GGA scores. Pooled odds ratios for lung cancer risk using LAA, fibrosis, GGA scores and reduced FEV₁/FVC and %VC were 3.63, 5.10, 2.71, 7.17 and 4.73, respectively ( P  < 0.0001 for all parameters). Multivariate regression analyses confirmed these results.
Conclusion:   Abnormal CT and spirometric parameters suggestive of COPD and ILD were strong risk factors for lung cancer, even after adjusting for gender, age and smoking status.