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PubMed1982

Efficacy and safety of aerosolized triamcinolone acetonide in steroid-dependent and steroid-independent chronic asthmatic patients.

Fourteen steroid-dependent and 16 steroid-independent asthmatic patients received aerosol triamcinolone acetonide for 12 weeks (two 200-micrograms inhalations four times daily). The mean daily oral steroid dose for the steroid-dependent patients was reduced from 12.5 mg at baseline to 1.34 mg after 12 weeks of aerosol therapy. In both groups of patients, FEV1.0, FVC and FEF25-75% values improved during therapy, usually at a statistically significant rate. Highly significant improvement occurred in shortness-of-breath, wheezing tightness-in-chest, and cough symptoms in all patients. However, changes in serum cortisol levels were not statistically significant. Side effects included transient hoarseness (seven patients), dry throat (one), and sore throat (one). No oral candidiasis was observed and no patient discontinued therapy because of side effects. Steroid withdrawal symptoms, which gradually abated, were experienced by half of the steroid-dependent patients. Aerosolized triamcinolone acetonide was therefore considered a safe and effective modality in the management of chronic asthma.

Adolescent↗
PubMed1975

Pulmonary function in asthmatic children during thalassotherapy.

In 39 asthmatic children, 5-14 years of age, sent to the Kinderkurheim Satteldüne for a 6 week course of thalassotherapy, the following pulmonary function studies were tested serially: Vital capacity (VC), one-second forced expiratory volume (FEV1), maximal mid-expiratory flow rate (MMFR) and peak flow rate (PFR). Results expressed as mean values per week of the group as a whole, showed subnormal results at initial testing in all 4 parameters measured. Improvement followed rapidly with the final level generally achieved during week 2. However, statistical analysis showed the differences between the initial and each of the subsequent values to be insignificant with one exception in the FEV1 values. Thus the clinical improvement observed in most patients during thalassotherapy could not be substantiated by pulmonary function tests.

Adolescent↗
PubMed1977

The effect on expiratory flow rates of smoking three cigarettes in rapid succession.

The effect of smoking three cigarettes in rapid succession on maximal and partial expiratory flow rates was studied in ten healthy smokers. The mean decrease in maximal midexpiratory flow and partial midexpiratory and end-expiratory flow was statistically significant. The response was maximal after the first cigarette. These results suggest that the instantaneous midexpiratory flow after 50% of the forced vital capacity has been exhaled is a useful indicator of irritation of the airways. Reduction of partial expiratory flow rates was three times greater than reduction of maximal expiratory flow rates. We suggest the use of partial expiratory flow curves as a screening test for irritants of the airways.

Adult↗
PubMed2005

Asthma in medium altitude--exercise-induced bronchoconstriction in hypobaric environment in subjects with asthma.

BACKGROUND: Hypoxic gas inhalation has been reported to enhance airway responsiveness and results in bronchoconstriction in animal models and in humans with asthma. However, the data have so far been conflicting. The aim of the present study was to examine the effect of reduced barometric pressure on exercise-induced bronchoconstriction (EIB) in subjects with asthma. METHODS: Twenty subjects (10-45 years old, male symbol/female symbol = 13/7) with asthma (at least 10% reduction in forced expiratory volume in 1-second postexercise) participated in exercise testing in barometric pressure corresponding to altitudes of 200 (normobaric) and 2500 (hypobaric) m above sea level in random order on separate days. Lung function was measured before and after exercise, as well as after inhalation of salbutamol. Heart rate, oxygen uptake (), arterial oxygen saturation (S(p)O(2)), respiratory gas exchange ratio (RER) and minute ventilation () were measured during exercise. RESULTS: There was no difference in lung function after exercise. The and HR(peak) during exercise did not differ. The RER(peak) was higher (P = 0.04) in hypobaric environment. The decreased 10.1% (7.2-13.0) [mean (95% confidence intervals)] (P < 0.001) from normobaric to hypobaric environment. At the same time, S(p)O(2) at decreased from 94.4 (92.2-96.6) to 85.6% (82.8-88.4) (P < 0.001). CONCLUSIONS: A barometric pressure corresponding to altitude of 2500 m did not increase EIB in subjects with asthma. The reduction in is most probably due to the lower S(p)O(2) in hypobaric environment.

Adolescent↗
PubMed1990

Efficacy and duration of action of oral procaterol in asthmatic children after single administration of different dosages.

A double-blind crossover study was performed to evaluate the bronchodilating effect of different single doses of procaterol (less than 0.5 micrograms/kg, 1.5 micrograms/kg, and placebo) orally administered. Sixteen asthmatic children, age 6-12 years, participated in the trial. Pulmonary function, heart rate, blood pressure, and tremor were evaluated at 30, 60, 90, and 120 min and then hourly for 8 hours after administration. All three doses were therapeutically effective. The 1.5 micrograms/kg dose produced a more sustained bronchodilatation effect, but was also associated with an increase in the incidence of tremors. The 0.5 micrograms/kg dosage may, however, be a good starting dose because it assures a reasonable risk/benefit ratio.

Administration, Oral↗
PubMed1976

A long-term study of low-dose aerosolized terbutaline sulfate.

The purpose of this study was to evaluate the safety and efficacy of a new lowdose terbutaline sulfate aerosol (375 micrograms) over a six-week period. The question of drug tolerance was also evaluated. Twenty-four ambulant patients with chronic obstructive pulmonary disease with a component of reversible airway disease was evaluated. The patients were tested at two-week intervals during a six-week period. The patients abstained from all bronchodilatory medications for at least 10 hours prior to the time of evaluation. The evaluation consisted of baseline FEV1 and MMEFR determinations, ECG, CBC, urinalysis, and renal and liver function tests. After the terbutaline was administered, a rhythm strip and pulmonary function tests were repeated at 5, 15, 30, 60, 120, and 180 minutes. Throughout the six-week study there was a statistically significant increase in FEV1 and MMEFR, (P less than 0.001). No change was noted in the systolic blood pressures; however, heart rate and diastolic blood pressure decreased significantly. No drug tolerance, paradoxical bronchospasm, subjective side effects, no abnormal laboratory results were noted during the study period.

Adult↗
PubMed1984

Fenoterol dose-response study in children with asthma.

We have studied the effect of fenoterol, a selective beta-2 adrenergic agent, on airway obstruction in children with asthma. The drug was administered orally in single doses of 2.5, 5, and 7.5 mg to 20 children with chronic stable asthma of moderate severity. The mean age of the children was 11.6 yr. Pulmonary function tests were performed as baseline at zero time and at intervals over a 6-hour period after drug administration. Onset of action for all doses was within 1 hr with a peak effect noted at 1.5 to 3 hr, and sustained improvement was observed over the entire 6 hr. The doses of 5 mg and 7.5 mg were equally effective in producing significant improvement of pulmonary function compared to 2.5 mg (p less than 0.05). Side effects remained acceptable for all patients. The 5 and 7.5 mg doses produced significant adverse effects that involved the central nervous and musculoskeletal systems, whereas the 7.5 mg dose caused a significant incidence of tachycardia. Our findings indicate: (1) fenoterol is a potent oral bronchodilator for large and small airways in children, (2) the 7.5 mg dose does not achieve any additive effect over a 5 mg dose; and (3) 5 mg is the optimal oral dose of fenoterol for children from age 8 to 12 yr.

Adolescent↗
PubMed2003

Training of aerobic and anaerobic fitness in children with asthma.

OBJECTIVE: To assess the effect of a training protocol on aerobic and anaerobic fitness in children with asthma. STUDY DESIGN: Sixteen boys (mean age: 13 years; range: 10-16 years) with mild-to-moderate asthma participated in a rehabilitation program that included 6 weeks of individualized training on a cycle ergometer. Two groups were randomly formed: the control group (CG, n = 7) and the training group (TG, n = 9), which exercised at an intensity set at the heart rate corresponding to the ventilatory threshold, with 1-minute sprints against the maximal aerobic power (MAP) every 4 minutes. Session duration was 45 minutes, 3 sessions per week. Changes in maximal oxygen uptake (VO(2)max), MAP, short-term peak power (PP), and pulmonary function were assessed. RESULTS: Two patients of the training group did not complete the study. Pulmonary function remained unchanged in both groups. Improvement in both aerobic and anaerobic fitness was significant only in the training group (TG vs CG): VO(2)max +18% +/- 2.1% versus +9% +/- 4.5% (P <.05), MAP +32% +/- 5% versus 12% +/- 7% (P <.05), PP +21% +/- 5.7% versus +8.8% +/- 10% (P <.01). CONCLUSION: Exercise training with high-intensity bouts is well tolerated in children with mild-to-moderate asthma. When included in a global rehabilitation program, this type of training improves both aerobic and anaerobic fitness. Anaerobic activities should be considered in sports rehabilitation programs for children with asthma.

Adolescent↗
PubMed1998

Determinants of aerobic and anaerobic exercise performance in cystic fibrosis.

We examined aerobic and anaerobic exercise performance in 17 subjects with cystic fibrosis (CF) (age 25+/-10 [SD] yr; 47% females; FEV1 62+/-21% pred) and 17 age- and sex-matched control subjects (age 25+/-8 [SD] yr; 41% females; FEV1 112+/-15% pred) in relation to pulmonary function and nutritional status. Aerobic capacity was determined as maximal oxygen consumption (VO2max) (ml/kg/min) and anaerobic threshold (AT; ml VO2/kg/min) from a graded exercise stress test on an electronically braked bicycle ergometer. Anaerobic performance was assessed from the average work of two bouts of pedaling to exhaustion at a load corresponding to 130% Vo2max from graded exercise. Both aerobic and anaerobic performances were decreased in subjects with CF (p < 0.001). The duration of anaerobic exercise in subjects with CF was similar to control subjects. In control subjects, pulmonary function did not correlate to aerobic or anaerobic exercise. In subjects with CF significant relationships between FEV1, vital capacity, and FEF25-75% to AT were found, suggesting the pulmonary limitation to aerobic capacity. In both patients with CF and control subjects, lean body mass and arm muscle area significantly correlated with anaerobic performance but not with VO2max or AT. We conclude that nutritional status, rather than pulmonary function, is the major determinant of anaerobic exercise capacity in CF. The preserved duration of anaerobic exercise at equivalent workloads (corresponding to 130% of VO2max from graded exercise) suggests that readily available energy stores in muscle may be similar in CF and normal individuals.

Adult↗
PubMed1989

Tachyphylaxis to systemic but not to airway responses during prolonged therapy with high dose inhaled salbutamol in asthmatics.

High doses of inhaled salbutamol produce substantial improvements in airway response in patients with asthma, and are associated with dose-dependent systemic beta-adrenoceptor responses. The purpose of the present study was to investigate whether tachyphylaxis occurs during prolonged treatment with high dose inhaled salbutamol. Twelve asthmatic patients (FEV1, 81 +/- 4% predicted), requiring only occasional inhaled beta-agonists as their sole therapy, were given a 14-day treatment with high dose inhaled salbutamol (HDS), 4,000 micrograms daily, low dose inhaled salbutamol (LDS), 800 micrograms daily, or placebo (PI) by metered-dose inhaler in a double-blind, randomized crossover design. During the 14-day run-in and during washout periods, inhaled beta-agonists were withheld and ipratropium bromide was substituted for rescue purposes. At the end of each 14-day treatment, a dose-response curve (DRC) was performed, and airway (FEV1, FEF25-75) chronotropic (HR), tremor, and metabolic (K, Glu) responses were measured at each step (from 100 to 4,000 micrograms). Treatment had no significant effect on baseline values. There were dose-dependent increases in FEV1 and FEF25-75 (p less than 0.001), and pretreatment with HDS did not displace the DRC to the right. DRC for HR (p less than 0.001), K (p less than 0.001), and Glu (p less than 0.005) were attenuated after treatment with HDS compared with PI. There were also differences between HDS and LDS for HR (p less than 0.001) and Glu (p less than 0.05) responses. Frequency and severity of subjective adverse effects were also reduced after HDS: tremor (p less than 0.001), palpitations (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Inhalation↗
PubMed1976

Inhibition of exercise-induced bronchospasm by atropine.

The ability of atropine to inhibit exercise-induced bronchospasm was evaluated in 18 children with chronic, perennial asthma. In 17 of 18 patients, exercise-induced bronchospasm was blocked by prior inhalation of 0.1 mg per kg of atropine sulfate, administered in a randomized single blind fashion. In 14 of these 17 patients, significant bronchodilatation occured after the combination of atropine and exercise. Placebo failed to inhibit exercise-induced bronchospasm in any patient. These results suggest that the parasympathetic nervous system has a role in the mediation of exercise-induced bronchospasm in children.

Adolescent↗
PubMed1993

Exercise-induced bronchospasm in nonasthmatic obese children.

The frequency, degree, and pattern of bronchial reactivity to exercise were compared in 13 obese and 14 control children, ages 6 to 10 years, with no history of asthma. Spirometry was performed before and every three minutes after a seven-minute exercise challenge on a treadmill. There were 11 obese children and 6 controls who had at least a 15% fall in at least one of three monitored pulmonary function parameters (P < .05). The group mean percentage falls in FEV1 and FEF25%-75% were significantly greater in the obese group than in the controls. The pattern of bronchospasm, occurring soon after the exercise challenge, is consistent with that found in the known asthmatic population. A significant correlation was found between triceps skin-fold thickness and degree of fall in FEF25%-75% (r = .55, P < .005). This study demonstrated that significantly greater frequency and degree of bronchospasm of the smaller airways occur in obese children, partially related to the amount of subcutaneous fat. Whether exercise-induced bronchospasm leads to exercise avoidance and obesity or whether obesity causes or enhances bronchial hyperreactivity to exercise requires further study.

Asthma, Exercise-Induced↗
PubMed1987

Respiratory responses to pirenzepine in healthy subjects.

Since no information is available concerning the action of pirenzepine in vivo on human tracheobronchial tree, we evaluated the respiratory responses to pirenzepine in a group of healthy subjects. This clinical study suggests that pirenzepine exerts its bronchodilatory action on small airways (from 9th generation to distal airways), but not on larger airways, in normal subjects. These results are consistent with a probable presence of muscarinic high affinity receptors (M1 subtype) only in peripheral airways.

Adolescent↗