Clinical and functional responses to salbutamol inhaled via different devices in asthmatic patients with induced bronchoconstriction

AIMS: This study aimed at evaluating changes in airway patency, lung volumes and perception of breathing discomfort intensity following salbutamol administration via the Diskus dry-powder inhaler (DPI) or a pressurized metered-dose inhaler with the Volumatic valved holding chamber (pMDI + Volumatic) in asthmatic patients with methacholine-induced bronchoconstriction. METHODS: On six different study days, 18 patients inhaled methacholine until forced expiratory volume in 1 s (FEV(1)) decreased by approximately 35% of baseline. Following placebo, 200 and 400 microg of salbutamol through the pMDI + Volumatic or the Diskus, changes in FEV(1), volume-adjusted mean forced expiratory flow from 25 to 75% of the forced vital capacity (isoFEF(25-75)), lung volumes and breathing discomfort intensity, assessed by visual analogue scale (VAS) score, were repeatedly measured over a 60-min observation period. RESULTS: Induced bronchoconstriction was accompanied by obvious reductions in lung volumes and increases in VAS score. After salbutamol administration, FEV(1) and VAS score changes were similar in all experimental conditions. However, following 400 microg salbutamol via pMDI + Volumatic, isoFEF(25-75) values increased up to 4.48 l s(-1) (95% confidence interval 4.06, 4.90), a significantly (P < 0.01) higher value than those attained in all other experimental conditions. Independently of the salbutamol dose, lung volumes rose to significantly (P < 0.01) higher levels in pMDI + Volumatic than in Diskus trials. The low salbutamol dose via the pMDI + Volumatic and the high dose via the DPI increased isoFEF(25-75) and lung volumes to similar extents. CONCLUSIONS: Salbutamol via the pMDI + Volumatic provides greater isoFEF(25-75) and lung volume increases in asthmatic patients with induced bronchoconstriction; salbutamol-induced changes in VAS scores poorly reflect those in small airway patency. The lack of differences in FEV(1) increases observed after 200 and 400 microg salbutamol may reflect attainment of the flat portion of the dose-response curve using either device.     

Comparison of fenoterol, isoproterenol, and isoetharine with phenylephrine aerosol in asthma

The bronchodilator effect of fenoterol hydrobromide (0.5, 1.25, and 2.5 mg) was compared with either isoproterenol (2.8 mg) or isoetharine (5 mg) with phenylephrine (1.25 mg) in a double-blind placebo-controlled study. When delivered by an intermittent positive-pressure breathing device to 24 nonsmoking young adult asthmatic subjects, fenoterol produced significant improvement in forced expiratory volume at 1 second (FEV1), in maximum midexpiratory flow (FEF25-75%), and in forced expiratory flow at 25 per cent of vital capacity (FEF25%) for 6 to 8 hours, whereas isoproterenol and isoetharine with phenylephrine produced improvement for 1 and 2 hours, respectively. The lowest dosage of fenoterol was as effective as the highest but had fewer adverse effects.     

Cardiorespiratory responses to submaximal incremental exercise are not affected by one night's sleep deprivation during the follicular and luteal phases of the menstrual cycle

The purpose of the study was to investigate the effects of one night's sleep deprivation on the cardiorespiratory responses to exercise during the follicular and luteal phases of the menstrual cycle. We have studied nine, healthy females aged 24-35 years with regular menstrual cycles. Each subject performed spirometric tests at rest and then an incremental exercise testing during 11-13 days of follicular phase and 22-24 days of luteal phase following one normal night's sleep or one night's sleep loss. Compared with resting values exercise produced significant increases in cardiorespiratory variables including oxygen uptake (VO2), carbon dioxide production (VCO2), tidal volume (VT), respiratory rate (RR), minute ventilation (VE), systolic blood pressure, heart rate (HR) and respiratory quotient (R). However, it did not alter significantly diastolic blood pressure, end-tidal PO2 (PETO2), end-tidal PCO2 (PETCO2) and arterial oxygen saturation (SaO2). Spirometric variables which include forced vital capacity (FVC), forced expiratory volume in one s (FEV1), FEV1/FVC%, forced expiratory volume in three s (FEV3), forced expired flow from 25-75% of FVC (FEF 25-75%), forced expired flow at 25% of FVC (FEF 25%), forced expired flow at 50% of FVC (FEF 50%), forced expired flow at 75% of FVC (FEF 75%), forced expired flow from 75-85% of FVC (FEF 75-85%), peak expiratory flow (PEF), expiratory reserve volume (ERV), inspiratory capacity (IC) and maximal voluntary ventilation (MVV) and cardiorespiratory variables were not different between the cycle phases after one normal night's sleep or one night's sleep deprivation. Neither menstrual cycle phase nor sleep deprivation affected spirometric and cardiorespiratory parameters. We suggest that one night's sleep deprivation does not produce alterations in spirometric parameters and cardiorespiratory responses to submaximal incremental exercise during the follicular and luteal phases.     

吸入布地奈德／福莫特罗和布地奈德／沙丁胺醇对哮喘急性发作儿童支气管扩张的效果探讨

目的比较吸入布地奈德（100μg）／福莫特罗（6μg）、布地奈德（100μg）／沙丁胺醇（100μg）组合在5—15岁儿童哮喘发作期对支气管扩张的效果。方法采用双盲随机对照试验,研究组给予使用布地奈德100μg＋福莫特罗6μg组合压力式定量气雾装置吸入（MDI）,对照组给予布地奈德100μg＋沙丁胺醇100μg组合MDI。所有的儿童接受三次剂量的药物,给药间隔时间在20分钟以内。分析比较FEV1（％预计值）以及修正的肺指标值（MPIS）,研究两组在1、5、15、30、60分钟后的药效。结果干预后两组之间1、5、15、30、60分钟FEV1（％预计值）的比较差异无统计学意义（P〉0．05）。而对照组、研究组自身的（FEV1％预计值）绝对变化值,从基线到60分钟的差值为（12．2±2．5）以及（9．4±2．0）,两组比较差异有统计学意义（t=3．50,P〈0．05）。在两组基线相比,1、5、15、30、50分钟,从基线FEV1百分比变化也相似。呼气峰流速（PEFR）,百分比预测PEFR,用力呼气流速50（FEF50）和百分比预测FEF50,在两组相似研究过程中不同时间点也相似。其他肺功能参数两组之间比较差异无统计学意义。结论沙丁胺醇或福莫特罗,在二定吸入剂量的作用下,对轻度哮喘急性发作期5～15岁之间的儿童,有类似的支气管扩张作用。     

Bronchodilator effect of delta1-tetrahydrocannabinol

1 delta1-trans-tetrahydrocannabinol, (delta1-THC) produces bronchodilatation in asthmatic patients. 2 Administered in 62 microliter metered volumes containing 50--200 microgram by inhalation from an aerosol device to patients judged to be in a steady state, it increased peak expiratory flow rate (PEFR) and forced expiratory volume in 1 second (FEV1). 3 The rate of onset, magnitude, and duration of the bronchodilator effect was dose related.     

支气管舒张试验在小气道病变患者中的临床应用价值

目的探讨支气管舒张试验在小气道病变患者中临床应用方面的价值,观察其对早期支气管哮喘有无预测价值。方法根据小气道病变诊断标准选取郑州大学第五附属医院门诊及住院部的104例小气道病变患者,观察所有患者支气管舒张试验的结果,并追踪患者病情转归。结果 104例患者中有33例阳性,71例阴性。阳性组和阴性组舒张前FEF25-75%、FEF50%(V50%)、FEF75%(V25%)比较差异有统计学意义(P<0.05),舒张前FEF25-75%、FEF50%(V50%)、FEF75%(V25%)与FEV1改善率和增加量均呈负相关。33例支气管舒张试验阳性患者中有23例患者确诊为支气管哮喘,小气道病变患者的支气管哮喘的发生率为21.02%。结论支气管哮喘可能多合并小气道病变,考虑小气道病变患者应早期行支气管舒张试验,该试验在小气道病变患者中的应用对支气管哮喘的发生可能有预测价值。     

Effects of fluticasone vs. fluticasone/salmeterol on airway calibre and airway hyperresponsiveness in mild persistent asthma

AIMS: Inhaled corticosteroids alone or in combination with long acting beta2-agonists are indicated for use in mild persistent asthmatics. We set out to evaluate effects on airway hyperresponsiveness (AHR) and airway calibre using hydrofluoroalkane fluticasone/salmeterol (FP/SM) vs. double the dose of fluticasone alone (FP). METHODS: Fourteen mild persistent asthmatics completed a randomized double-blind crossover study with 1-week run-in and washout periods prior to treatments. Subjects received 3 weeks of FP 250 microg or FP 125 microg/SM 25 microg as 1 puff twice daily. Methacholine PD20 and lung function were measured after both baseline and treatment periods. RESULTS: There were no significant differences in baseline values prior to randomized treatments. Compared with pooled baseline, FP/SM and FP conferred improvements (P < 0.05) on methacholine PD20: 2.5 (95% confidence interval 1.7, 3.2) and 1.6 (0.8-2.3) doubling dose improvements, respectively; between FP/SM vs. FP there was a 0.9 (0.4, 1.4) doubling dose difference (P < 0.05). For forced expiratory volume in 1 s (FEV1), forced mid-expiratory flow (FEF25-75) and morning peak expiratory flow (PEF), FP/SM but not FP conferred improvements (P < 0.05) compared with pooled baseline, with FP/SM being greater than FP (P < 0.05): differences in FEV1 of 7.2% (3.8, 10.6) predicted, FEF25-75 of 11.2% (6.3, 16.1) predicted, and morning PEF of 17 L x min(-1)(1-32). CONCLUSIONS: FP/SM conferred improvements on AHR and airway calibre, while twice the dose of FP improved only AHR in patients with mild asthma. The differential effects of FP/SM and FP suggest separate but complementary actions of the two moieties on airway inflammation and smooth muscle stabilization. This may explain the beneficial effects of combination inhalers on exacerbations.     

Effect of oral contraceptives on respiratory function

The present study was carried out to assess the lung functions in oral contraceptive administered women. Lung function tests were carried out with Spirometer (Vitallograph Compact II). A significant increase in vital capacity (VC) was observed in these women as compared to normal control. There was also a significant decrease in forced expiratory volume in 1 sec./vital capacity (FEV1/VC%) and forced expiratory volume in 1 sec./forced vital capacity (FEV1/FVC%) among oral contraceptive administered women as compared to controls. Further, a significant increase in peak expiratory flow rate (PEF), reduction in forced expiratory flow rate (FEF75-85%) and FEF75% were observed among oral contraceptive administered women as compared to controls. The increase in VC and PEF might be due to the synthetic form of progesterone (progestins) present in oral contraceptive pills which causes hyperventilatory changes. Synthetic progesterone during luteal phase of menstrual cycle might increase the static and dynamic volumes of lung i.e. VC and PEF. But FEF75% showed a decrease which might be due to the lower neuromuscular coordination during breathing.     

Chronically inhaled salmeterol improves pulmonary function in heart failure

Inhaled beta-agonists are commonly prescribed for the symptoms of exercise intolerance in heart failure despite a paucity of data regarding their safety and efficacy. This was a prospective, randomized, double-blind, double-dummy, placebo-controlled 14-day cross-over study to determine if chronic inhaled salmeterol therapy 84 microg every 12 hours improved pulmonary function without augmentation of neurohormonal systems or ventricular ectopy in 8 symptomatic heart failure subjects with left ventricular ejection fraction (LVEF) <40% and FEV1 相似文献   

小气道功能指标在儿童哮喘病情严重程度评估及临床诊断中的应用

目的 探讨小气道功能指标在儿童哮喘病情严重程度评估及临床诊断中的应用价值。方法 选取2013年5月至2016年4月于郑州市第二人民医院56例哮喘急性发作期病儿作为哮喘组,并根据哮喘急性发作严重程度分为轻度(21例)、中度(20例)和重度(15例)三个亚组,同时选取同期、年龄相仿及性别相匹配的30例因其他原因引起喘息咳嗽的慢性炎症病儿和32例入院检查健康儿童分别作为非哮喘组和对照组,收集各组儿童一般资料,采用肺功能测定系统检测各组儿童用力肺活量(FVC)、最大呼气流量(PEF)、第1秒用力呼气容积(FEV1)和FEV1/FVC比值、呼出25%肺活量时呼气流速(FEF25%)、呼出50%肺活量时呼气流速(FEF50%)、呼出75%肺活量时呼气流速(FEF75%)、最大中期呼气流速(MMEF)等指标。结果 与对照组比较,非哮喘组和哮喘组病儿FVC、FEV1、PEF、FEF25%、FEF50%、FEF75%和MMEF等指标均显著降低(P<0.05),且哮喘组病儿上述指标显著低于非哮喘组[(1.42±0.36)L比(1.85±0.47)L、(1.25±0.32)L比(1.42±0.41)L、(2.68±0.64)L比(3.25±0.77)L/s、(2.54±0.65)L/s比(3.74±0.68)L/s、(1.58±0.36)L/s比(2.24±0.71)L/s、(0.61±0.37)L/s比(1.02±0.41)L/s、(1.42±0.49)L/s比(1.89±0.68)L/s)](均P<0.05),而三组病儿FEV1/FVC指标差异无统计学意义(P>0.05)。哮喘急性发作期不同程度病儿用力呼出25%肺活量的呼气流量占预计值百分比(FEF25pred%)、用力呼出50%肺活量的呼气流量占预计值百分比(FEF50pred%)、用力呼出75%肺活量的呼气流量占预计值百分比(FEF75pred%)、最大呼气中期流量占预计值的百分比(MMEFpred%)等指标比较差异有统计学意义(P<0.05),且随着病情程度增加,病儿FEF25pred%、FEF50pred%、FEF75pred%、MMEFpred%等指标呈现明显降低趋势(P<0.05),FEF25%和FEF75%指标在不同严重程度哮喘病儿中异常率比较,差异有统计学意义(P<0.05),FEF50%和MMEF指标比较差异无统计学意义(P>0.05),其中FEF25%主要表现为轻度异常,而FEF75%主要表现为重度异常。结论 小气道功能指标在儿童哮喘病情严重程度评估及临床诊断具有重要意义,随着病情加剧,小气道功能指标明显降低,且异常率显著增加。     

沙美特罗/丙酸氟替卡松对哮喘儿童肺功能的改善及临床意义

目的:观察沙美特罗/丙酸氟替卡松对哮喘儿童肺功能改善情况。方法:采用德国Jaeger公司的MasterscreenIOS测定仪,对61例支气管哮喘患儿在沙美特罗/丙酸氟替卡松治疗前后进行通气肺功能(F-V)和脉冲振荡(IOS)检测。观察用力肺活量(FVC)、第一秒用力呼气容积(FEV1)、最大呼气流速(PEF)、呼出25%肺活量时最大呼气流量(FEF25)、呼出50%肺活量时最大呼气流量(FEF50)、呼出75%肺活量时最大呼气流量(FEF75);呼吸阻抗(Zrs)、气道总阻力(R5)、中心气道阻力(R20)、响应频率(Fres)。结果:沙美特罗/丙酸氟替卡松治疗后FVC、FEV1、PEF均明显升高(P<0.001),而Zrs、R5、R20、Fres均明显降低(P<0.05),两者检查结果均有显著统计学意义。结论:吸入沙美特罗/丙酸氟替卡松能改善哮喘儿童的肺通气功能,降低气道阻力,是治疗儿童哮喘的理想药物之一。     

Longitudinal study of lung function development in a cohort of Indian medical students: interaction of respiratory allergy and smoking

This study was done to identify some factors that affect the growth and development of lung function during adolescence and early adulthood. Forced expiratory spirograms and peak expiratory flow rates were obtained in a cohort of normal young men (n = 63) over a period of 4 years, at intervals of approximately 2 years. Two factors that disturbed the normal pattern of lung function development in this group were smoking and respiratory allergy. Among the smokers and the allergics the decline in the forced expiratory volume expressed as a percentage of the forced vital capacity (FEV1%), the forced expiratory flow in the middle half of the forced vital capacity (FEF25-75%) and the FEF25-75% expressed as a ratio of the forced vital capacity (FEF/FVC) was more than double that among the normal subjects. The number of smokers and of allergics increased during the course of the study from 15 to 19 and from 16 to 23 respectively. There was a significant (P less than .01) interaction between smoking and the manifestation of respiratory allergy. Among nonsmokers, the number of allergic subjects increased from 12 to 13, while among smokers it increased from 4 to 10, during the four years.     

Reducing electrostatic charge on spacer devices and bronchodilator response

AIMS: Plastic spacers are widely used with pressurized metered dose inhalers (pMDI). Reducing electrostatic charge by washing spacers with detergent has been shown to greatly improve in vitro and in vivo drug delivery. We assessed whether this finding is associated with an improved bronchodilator response in adult asthmatics. METHODS: Twenty subjects (age 18-65 years) with a known bronchodilator response inhaled in random order salbutamol from a pMDI (Ventolin) through an untreated new spacer (Volumatic) and through a detergent washed spacer. Patients received the following doses of salbutamol via pMDI at 20 min intervals: 100 microg, 100 microg, 200 microg, 400 microg, 800 microg. Spirometry, heart rate and blood pressure were checked prior to each dose and 20 min after the last dose. RESULTS: There were no differences between baseline forced expiratory volume in 1 s (FEV1) using either spacer (2.61+/-0.56 and 2.52+/-0.45 l, untreated and treated with detergent, respectively; mean +/- s.d.). The provocation dose required to cause a clinically significant improvement of 10% in FEV1 (PD10) was significantly lower when the detergent treated spacer was used (1505 +/-1335 and 430+/-732 microg, untreated and treated, respectively, P<0.002). CONCLUSIONS: We have demonstrated an improvement in bronchodilator response, in adult asthmatics, after reducing the electrostatic charge in a spacer device by washing it with ordinary household detergent. This finding stresses the importance of an optimal choice of delivery device for asthma medication.     

Long-term effect of the beta2-receptor agonist procaterol on daily life performance and exercise capacity in patients with stable chronic obstructive pulmonary disease. Clinical study with special reference to health-related quality of life and activities of daily living

The present study was undertaken to evaluate the long-term effect of procaterol hydrochloride (CAS 62929-91-3, Meptin), a third generation beta2-receptor agonist on lung function, exercise capacity, health-related quality of life (HRQOL) and activities of daily living (ALDs) in patients with stable chronic obstructive pulmonary disease (COPD). Twenty patients were randomly assigned to the procaterol group or to the control group, who received oxitropium bromide (CAS 30286-75-0), an anticholinergic agent. Procaterol was inhaled three times a day at a dose of 20 pg, while oxitropium was inhaled three times a day at a dose of 200 microg. The subjects were evaluated based on spirometry, exercise capacity, the Borg Scale, HRQOL, and ADLs before and after 12, 24 and 52 weeks of therapy. The values of forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), total lung capacity (TLC), functional residual capacity (FRC), residual volume (RV), maximal inspiratory pressure (PImax), and maximal expiratory pressure (PEmax) were significantly improved at 12, 24 and 52 weeks compared with baseline values in the procaterol group (p < 0.05, p < 0.01), while these values did not differ from baseline values at any point in the oxitropium group (p > 0.05). Additionally, 6-min walking distances and Borg Scale values showed significant improvement at 12, 24 and 52 weeks compared with baseline values in the procaterol group (p < 0.05, p < 0.01), but did not significantly differ from baseline values in the oxitropium group at any point (p > 0.05). Likewise, the scores for dyspnea, fatigue, emotional function, mastery, total scores and ADLs were significantly higher at 12, 24 and 52 weeks compared with the baseline values in the procaterol group (p < 0.05, p < 0.01), but did not differ at any point in the oxitropium group (p > 0.05). These results suggest the effectiveness of long-term regular bronchodilator therapy with the beta2-receptor agonist procaterol in patients with stable COPD.     

Effectiveness and acceptability of a domiciliary multidrug inhalation treatment in elderly patients with chronic airflow obstruction: metered dose inhaler versus jet nebulizer.

The aim of this study was to compare the immediate and long-term bronchodilator effect as well as the patient acceptability of a 2-week, multidrug, inhalation treatment delivered by a metered dose inhaler (MDI) versus a jet nebulizer in a group of elderly patients with chronic obstructive pulmonary disease (COPD) or asthma and an at least partially reversible airflow obstruction. Twenty elderly outpatients (17 men; mean +/- SD age, 67 +/- 2 years; mean +/- SD baseline forced expiratory volume in 1 second [FEV1], 46.5 +/- 14% of predicted value) with COPD or asthma participated in the study, which was of an open, randomized, crossover design. After a 1-day baseline evaluation, including patient history, clinical examination, and spirometry, participants were randomly assigned to receive a multidrug inhalation treatment (a combination of salbutamol, ipratropium, and flunisolide) with either an MDI or a jet nebulizer. Two weeks later, they were shifted to treatment with the alternative system for a further 2 weeks. FEV1 was measured on the first and fourteenth days of each treatment period, on each occasion both before and 30 minutes after the morning inhalation. At the end of the study, patients were asked to express a personal preference for one of the two inhalation treatments with regard to effectiveness and acceptability by filling out a simple questionnaire. Both the MDI and jet nebulizer had a significant immediate bronchodilator effect on the first and fourteenth days of treatment, with no differences between treatments. No long-term bronchodilator effect was seen with either aerosol delivery system. Patient preferences were clearly in favor of the jet nebulizer with regard to effectiveness and in favor of the MDI with regard to acceptability. In conclusion, in elderly patients with COPD or asthma and partially reversible airflow obstruction, a maintenance multidrug bronchodilator/anti-inflammatory inhalation treatment produced a statistically significant and clinically relevant bronchodilator effect without substantial differences between the two delivery systems. Most patients considered the MDI to be more acceptable and the jet nebulizer to be more effective. These preferences should be taken into consideration when prescribing a maintenance aerosol inhalation treatment.     

A new bronchodilating agent, procaterol, in preventing exercise-induced asthma

The aim of the present study was to verify the effectiveness of procaterol, a recent and specific beta-2-adrenoceptor stimulant, in preventing exercise-induced asthma (EIA). Twelve asthmatic patients were selected aged 18.6 +/- 5.6 years with a positive response to EIA and a basal forced expiratory volume of the first second (FEV1) better than 80% of predicted. The patients underwent four bronchoprovocation challenges on four consecutive days. On the first day they performed an inclusion test, and, on the three subsequent days, they were submitted, to three identical standardized challenges according to a randomized design. Fifteen minutes before, procaterol (20 mcg), salbutamol (200 mcg) and a placebo were administered as metered aerosol. No pharmacological treatment was given for 24 h (48 h for antihistamines) before each challenge. The test was carried out running on treadmill (10% grade) for 7 min. Room temperature (20-25 degrees C) and relative humidity (40-55%) were maintained constant. At baseline, 15 min before, 5, 10, 15, 30 and 60 min after the exercise, lung function was assessed. Basal mean values of FEV1 were 94.7, 94.9, 90.7 and 91.5% of predicted for the inclusion and the three protected tests, respectively, without significant differences. The FEV1 mean values showed a mild bronchodilation 15 min after salbutamol (+13.2%, p less than 0.006) and procaterol (+8%, NS). At every considered time all indices showed a significant gap (p less than 0.01) between drugs and the placebo with no appreciable differences between procaterol and salbutamol.     

Assay-dependent kinetics of heparin: evidence for rapid in vivo activation of heparin.

We have compared bronchodilator dose-response curves to inhaled salbutamol in seven normal and eight asthmatic subjects. In all normal subjects maximal bronchodilatation measured by partial flow volume curves was achieved at a cumulative dose of 110 micrograms. The dose necessary to produce half maximal response (ED50) was 23 +/- 2 micrograms (mean +/- s.e. mean) with a range of 18-28 micrograms. In asthmatic subjects maximal bronchodilatation measured by FEV1 and by maximal flow volume curves was achieved at significantly higher (P less than 0.01) doses of salbutamol with a mean ED50 of 83 +/- 28 micrograms and range of 25-251 micrograms. There was a significant (P less than 0.05) correlation between ED50 and % predicted baseline FEV1. This is more likely to reflect impaired access of drug for airway beta-adrenoceptors than impaired beta-adrenoceptor function in asthma. In five asthmatic subjects dose-response curves to salbutamol and isoprenaline were compared and found to be similar, thus providing no evidence that salbutamol is a partial agonist in vivo, as it appears to be in vitro.     

Comparison of the Bronchodilator Effect of Inhaled Short- and Long-Acting beta(2)-Agonists in Children with Bronchial Asthma: A Randomised Trial

OBJECTIVE: This study compared the bronchodilator effects of short-acting (salbutamol and procaterol) and long-acting (salmeterol and formoterol) beta(2)-agonists in children with bronchial asthma. PATIENTS: Twenty-seven (18 male, 9 female) children with bronchial asthma were enrolled in the study. Drugs were administered randomly in the morning for 5 days as follows: 1 single dose of two short-acting beta(2)-agonists, salbutamol 200microg and procaterol 20microg, and two long-acting beta(2)-agonists salmeterol 50microg and formoterol 24microg, and placebo. RESULTS: All beta(2)-agonists demonstrated a significantly higher bronchodilator effect than that observed with placebo. This effect appeared to be due to the forced expiratory flows. Formoterol produced a higher bronchodilator effect than salbutamol, and salmeterol showed a bronchodilator effect comparable with salbutamol at 30 minutes but higher than salbutamol after 3 hours. CONCLUSION: Our study confirmed the efficacy of the bronchodilator effects of the beta(2)-agonists. Salmeterol and formoterol, in particular, produced an improvement in respiratory function with a significant increase in forced expiratory flows in children with bronchial asthma.     

Bronchial lability in allergic rhinitis.

The aim of this study was to assess the relationship between exercise bronchial lability and the changes in pulmonary function over a one year period in allergic rhinitis. Eighty four nonsmoking male medical students of whom twenty two were allergic rhinitics were studied. Pulmonary function status was significantly lower and exercise bronchial lability significantly higher in the allergics. Over a one year period the mean decline in the forced expiratory volume in one second (FEV1) was three times greater and in the forced expiratory flow rate in the middle half of the vital capacity (FEF 25-75%) 50% greater among the allergics. The change in FEV1 was positively related to the bronchial lability, indicating that greater bronchial lability was associated with less decline in pulmonary function in these subjects.     

Pulmonary functions in air conditioner users

Air conditioning may affect human health since it has profound effect on our environment, than just lowering temperature. The present study was planned to assess the effect of air conditioners (AC) on pulmonary functions in young healthy non-smoker males. The study group comprised of ten subjects who were using AC's in their cars for at least 1 hr daily since last 6 months. While ten subjects who did not use AC at all served as controls. The pulmonary functions were assessed using PK Morgan 232 spirometer in a closed room. The peak expiratory flow rate (PEFR) and Forced expiratory flow between 25-75% of vital capacity (FEF25-75) were significantly reduced in subjects using car AC's. Inspiratory flow rates also showed a trend towards decline in AC users but could not reach the level of significance. The lung volumes and capacities were not significantly different in the two groups except for forced expiratory volume in 0.5 sec (FEV 0.5 sec), which also decreased in AC users. The airway resistance and lung compliance did not show significant change. In the presence of normal FEV1, reduced FEF25-75% which is the flow rate over the middle half of vital capacity, is an evidence of mild airflow limitation. The result is suggestive of predisposition of AC users towards respiratory disorders in form of mild airflow restriction.