Comparison of Bricanyl® Turbuhaler and Berotec® dry powder inhaler

Terbutaline (Bricanyl) 0.5 mg t.i.d. administered via Turbuhaler was compared with fenoterol (Berotec) 0.2 mg t.i.d. administered via Inhalator Ingelheim in 36 asthmatic children aged 7-12 years. The study was of an open crossover design with two randomly allocated treatment periods, each lasting 2 weeks. Forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) were measured at clinic visits before study start and at the end of each treatment period. The patients recorded peak expiratory flow (PEF) before and after inhaler use, morning and evening. They also recorded asthma symptoms and number of extra inhalations. At the end of the study, children and parents were asked for inhaler preference. No differences between the treatments were found concerning the results of the lung function measurements at the clinic or at the PEF measurements at home. No differences were found between the treatments as regards asthma symptoms or number of extra inhalations. Two patients experienced mild side effects during fenoterol treatment, none during terbutaline treatment. Treatment with terbutaline in Turbuhaler was preferred by a majority of children and parents. In conclusion, in this group of asthmatic children, treatment with terbutaline administered via Turbuhaler was as efficacious as treatment with fenoterol administered via Inhalator Ingelheim. There was a clear preference in favour of the Turbuhaler.     

Twice or four times daily beclomethasone dipropionate in mild stable asthma?

A double-blind cross-over study lasting 16 weeks was conducted to establish if a twice daily regimen of beclomethasone dipropionate (BDP) was as effective in controlling asthma as a four times daily regimen. The patient's need for inhaled steroids (100 meg BDP qds) was confirmed prior to entering the study by deterioration of peak expiratory flow rates and/or increased bronchodilator usage during a single-blind placebo period of 6 weeks. Thirty six asthmatics were eligible to enter the study and completed both treatment periods. Daily record cards of symptom scores, four times daily peak expiratory flow rate measurements and inhaled bronchodilator usage were recorded throughout the study. There was no significant difference between the mean PEFR measurements taken four times each day and the variability in PEFR, between the two treatment groups. Symptom scores for cough, wheeze, breathlessness and overall disability also showed no significant difference. Symptomatic inhaler usage for the two groups was similar. Lung function measurements of FEV₁, FVC and VC were almost identical; FEV₁ being 2.1 1 on twice daily regimen and 2.2 1 on four times daily regimen. A slight variation was observed in PEFR taken at the end of each treatment period at the clinic visits, being 3611/min on twice daily and 3801/min on four times daily drug dosage. In stable asthmatics, the control of asthma measured both symptomatically and by daily lung function was independent of dosing schedule, but twice daily treatment may well lead to better compliance.     

Terbutaline controlled-release tablets and ipratropium aerosol in nocturnal asthma

The effect of oral terbutaline (controlled-release [CR] tablets) was compared with that of inhaled ipratropium bromide (aerosol) in 21 patients with nocturnal asthma. In a randomized, double-blind, crossover study, 40 μg four times daily, and the two drugs in combination. Each treatment was given for 3 weeks. Before the start of the study, the patients participated in a 1-week run-in period. The mean nocturnal decline in peak expiratory flow rate (PEFR) was 29% in the run-in period and was reduced to 22% in the terbutaline CR period, 27% in the ipratropium period, and 23% in the period with the combination of the two drugs. The mean night PEFR was significantly ( P <0.05) higher in the period with terbutaline CR, as compared with the period with ipratropium. The mean morning PEFR was also highest in the terbutaline CR period. The mean evening PEFR was significantly ( P < 0.05) higher during treatment with terbutaline CR alone or the combination was preferred by as many patients as was treatment with ipratropium alone. When present, adverse reactions were to be milk or moderate.
Treatment with terbutaline CR alone and the combination significantly improved the evening and night PEFR, as compared with ipratropium alone.     

Terbutaline Slow-Release Tablets in Children with Bronchial Asthma

The effect of terbutaline sulphate in slow-release (SR) tablets (Bricanyl Depot), 5 mg twice daily, was compared with that of terbutaline sulphate in ordinary tablets (Bricanyl), 2.5 mg three times daily, in a double-blind, randomized, cross-over study during 2 consecutive weeks in 10 asthmatic children. Plasma concentrations and urinary excretion of terbutaline were measured at various times during both treatment periods. The SR tablets produced a higher mean plasma concentration in the morning and a smaller peak-trough variation over the day than the ordinary ones. No differences between the two treatments were observed concerning FEV1 (forced expiratory volume in 1 s). Tremor, measured with an opto-electronic tremorgraph, was about the same for two treatments and not significantly different from tremor seen in healthy children. The reported side effects were less frequent in the SR tablet period.     

Nocturnal asthma: effect of treatment with oral sustained-release terbutaline, inhaled budesonide, and the two in combination

The purpose of this study was to compare effect of treatment with an oral long-acting beta 2-agonist (sustained-release terbutaline, Bricanyl depot), an inhaled steroid (budesonide, Pulmicort), and the combined treatment in patients with nocturnal asthma. Thirty-seven patients completed the study. During a 1-week run-in period with inhaled terbutaline monotherapy, the mean nocturnal asthma score was 1.0 (+/- 0.1) (corresponding to one awakening every night), and the mean overnight fall in peak expiratory flow rate was 27.7% (+/- 2.0). The patients were randomly entered into double-blind, crossover periods of 3 weeks each: (1) sustained-release terbutaline, 10 mg twice daily (b.i.d.), (2) sustained-release terbutaline, 10 mg b.i.d., and two puffs (400 micrograms) of budesonide, b.i.d., and (3) two puffs (400 micrograms) of budesonide, b.i.d. The combined treatment resulted in significantly lower overnight fall in peak expiratory flow rate (6.9% +/- 1.4 compared to 9.4% +/- 2.0 during sustained-release terbutaline and 10.4% +/- 1.9 during budesonide) and less nocturnal awakenings (nocturnal asthma score 0.15 +/- 0.05, 0.43 +/- 0.09, and 0.26 +/- 0.06, respectively) than either single treatment alone (p less than 0.05). The differences between the single treatments were not significant. We thus found that an inhaled steroid is as effective as a long-acting oral beta 2-agonist in controlling nocturnal asthma and that the combination is better. The observed differences were, however, small, and other studies would be required to evaluate the clinical significance of the present finding.     

Leukotriene receptor antagonist, montelukast, can reduce the need for inhaled steroid while maintaining the clinical stability of asthmatic patients

BACKGROUND: Oral leukotriene receptor antagonists have been shown to have efficacy in chronic asthma. OBJECTIVE: To determine whether the addition of montelukast could lead to a reduction in inhaled corticosteroid dose without a significant decrease in peak expiratory flow rate (PEFR). METHODS: After a 4-week run-in period, 191 moderate-to-severe asthmatic patients whose asthma had been well controlled with daily inhaled corticosteroid therapy (beclometasone dipropionate 800 to 1600 micro g/day), were randomly assigned to one of two treatments - placebo (n = 98) or montelukast 10 mg once daily (n = 93) - for a 24-week, multicentre, double-blind, treatment period. At the beginning of the active treatment period, the daily dose of inhaled corticosteroid was halved in all of the patients. In addition, the inhaled corticosteroid dose was subsequently titrated every 8 weeks, based on PEFR, asthma symptoms and beta-agonist use. RESULTS: After 8 weeks of a 50% reduction in inhaled corticosteroid use, morning PEFR increased by 5.3 +/- 32.3 L/min from baseline in patients receiving montelukast and significantly decreased by 6.9 +/- 29.0 L/min in those receiving placebo (P = 0.035). In addition, evening PEFR significantly decreased by 9.8 +/- 28.5 L/min (P = 0.003) in the placebo group, but was maintained in the montelukast group. In spite of a subsequent 50% reduction in the inhaled corticosteroid dose every 8 weeks, morning and evening PEFRs were maintained over the 24-week treatment period in the montelukast group; PEFR significantly decreased in the placebo group. There was a significant difference between the two groups with regard to morning PEFR, therapy score and asthmatic score at weeks 8, 16 and 24, as well as evening PEFR at week 8. However, the symptom scores were not significantly different between the two groups or within each group. CONCLUSION: These data suggest that montelukast reduces the need for inhaled corticosteroids while maintaining asthma control over a 24-week period. Therefore, montelukast may be useful for long-term treatment in patients with asthma who require high doses of inhaled corticosteroids.     

Epinephrine improves expiratory flow rates in patients with asthma who do not respond to inhaled metaproterenol sulfate

One hundred patients with acute asthma and peak expiratory flow rates (PEFR) less than 150 L/min were randomized and treated in a double-blind treatment protocol with either metaproterenol sulfate aerosol (MPA) inhalation and placebo injection or epinephrine injection (EPI) and inhaled placebo at entry and at 30 and 60 minutes, and then were treated with the crossover comparison regimen at 120, 150, and 180 minutes. The two groups had similar entry PEFRs and FEV1 (MPA, 112 L/min; 0.94 L, respectively; EPI, 111 L/min; 0.85 L, respectively) and similar plasma theophylline levels (MPA, 12.2 micrograms/ml; EPI, 13.8 micrograms/ml). PEFR and FEV1 were measured every 30 minutes for 4 hours. Mean expiratory flow rates among both groups were similar at entry and at 120 and 240 minutes. At 120 minutes, flow rates had improved in 28/46 MPA-treated patients (61%) and 48/54 EPI-treated patients (89%). Among these improved patients, flow rates were significantly higher in the MPA-treated group. At 120 minutes, 18/46 MPA-treated patients (39%) and 6/54 EPI-treated patients (11%) had PEFRs less than 120 L/min and PEFR and FEV1 less than 120% of baseline values (p less than 0.01). In 13 of these 18 MPA-treated patients who did not improve compared to 1/6 EPI-treated patients who did not improve, PEFRs were greater than 120 L/min, and PEFR and FEV1 had increased 20% or more above baseline values after treatment with the crossover comparison regimen (p less than 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)     

Relationship between symptoms and objective measures of airway obstruction in asthmatic patients.

The objective of this study was to determine the relationship between asthma symptoms and the degree of airway obstruction as measured by the forced expiratory volume in one second (FEV1) and peak expiratory flow rate (PEFR) in a group of 64 asthmatic patients with clinically stable disease attending a university-based urban asthma clinic. Asthma symptoms did not correlate with the degree of airway obstruction as measured by prebronchodilator PEFR (total asthma symptom score vs PEFR: r = -0.214, p = 0.104, n = 59) and only correlated poorly with prebronchodilator FEV1 (total asthma symptom score vs FEV1: r = -0.256, p = 0.041, n = 64). These results lend support to the recommendation that airway obstruction should be measured objectively when assessing patients with chronic persistent asthma.     

Once-daily budesonide via Turbuhaler improves symptoms in adults with persistent asthma.

BACKGROUND: Previous studies have demonstrated the efficacy and safety of twice-daily budesonide Turbuhaler (Pulmicort Turbuhaler, AstraZeneca, Wilmington, DE) for the treatment of mild to severe asthma. OBJECTIVE: To compare the efficacy and safety of budesonide Turbuhaler administered once daily each morning with placebo in inhaled corticosteroid-naive adults with persistent asthma. METHODS: In this randomized, double-blind, placebo-controlled, multicenter study, 177 adults (aged 18 to 70 years) received placebo or once-daily budesonide Turbuhaler (400 microg) for 12 weeks. Efficacy variables included mean changes from baseline in forced expiratory volume in 1 second (FEV1) and AM/PM peak expiratory flow rate (PEFR), and nighttime/daytime asthma symptom scores, patient discontinuations, use of breakthrough medication (albuterol), forced vital capacity (FVC), forced expiratory flow between 25% and 75% of FVC (FEF25%-75%), and quality of life assessments. Safety was evaluated based on adverse events, physical examinations, vital signs, and laboratory tests. RESULTS: Demographic and baseline characteristics were comparable between study groups. The mean percentages of predicted FEV1 at baseline were 71.9 +/- 9.8 in patients receiving budesonide Turbuhaler and 70.6 +/- 11.0 in patients receiving placebo. Mean changes from baseline over the 12-week treatment period in FEV1 were significantly (P = 0.007) improved in patients receiving once-daily budesonide Turbuhaler compared with placebo (0.31 L and 0.17 L, respectively). Significant (P < or = 0.037) improvements over placebo also were observed in AM PEFR, nighttime/daytime asthma symptoms, and albuterol use with budesonide Turbuhaler treatment. Adverse events were generally mild or moderate in intensity and similar between study groups. CONCLUSIONS: Budesonide Turbuhaler 400 microg administered once daily in the AM is efficacious and safe for inhaled corticosteroid-naive asthmatic adults.     

Comparison of a beta 2-agonist, terbutaline, with an inhaled corticosteroid, budesonide, in newly detected asthma

BACKGROUND. The presence of airway inflammation even in mild asthma points to the potential value of antiinflammatory therapy. We compared the effect of an inhaled corticosteroid, budesonide, with that of an inhaled beta 2-agonist, terbutaline, in the long-term treatment of newly detected asthma. METHODS. We studied 103 patients (29 male and 74 female patients 15 to 64 years old) in whom asthma had appeared within the previous year. The patients were randomly assigned in blinded fashion to two treatment groups: one to receive 600 micrograms of inhaled budesonide twice a day, and the other to receive 375 micrograms of inhaled terbutaline twice a day. The study period was two years. RESULTS. After six weeks of treatment, the patients treated with budesonide tolerated inhaled histamine better than the patients treated with terbutaline (a difference of one doubling dose step, P less than 0.001), and the difference was sustained. Patients' diaries kept during the first three months of the study and during the last month of the first and second years showed budesonide to be more effective than terbutaline in improving peak expiratory flow in the morning (average increase from the pretreatment value, 32.8 liters per minute for budesonide vs. 4.8 liters per minute for terbutaline; P less than 0.001) and in the evening (P less than 0.01). Budesonide was also more effective in reducing the symptoms of asthma (P less than 0.01) and the use of supplemental beta 2-agonist medication (P less than 0.01). Ten patients were withdrawn from the terbutaline group because treatment was insufficiently effective, whereas only one dropped out of the budesonide group. The adverse reactions to both treatments were few and mild. CONCLUSIONS. Antiinflammatory therapy with inhaled budesonide is an effective first-line treatment for patients with newly detected, mild asthma, and it is superior to the use of terbutaline in such patients.     

The short-term bronchodilator effects of fenoterol and ipratropium in asthma

We studied the bronchodilator effects of inhaled fenoterol, a relatively selective beta-2 adrenergic agent, and ipratropium an anticholinergic drug, singly and in combination in 10 patients with asthma. The period of observation was 6 hr after aerosol administration. The six drug regimens used were fenoterol 100 micrograms, fenoterol 200 micrograms fenoterol 50 micrograms combined with 20 micrograms of ipratropium, fenoterol 100 micrograms combined with 40 micrograms of ipratropium, 40 micrograms of ipratropium, and placebo. Measurements consisted of spirometry with determination of forced expiratory volume in one second (FEV1), maximal expiratory flow at 50% of vital capacity (V50), specific airway conductance, lung volumes, and heart rate. Bronchodilation with regimens containing fenoterol was rapid, with 75% of the maximum response achieved by 5 min, while the peak effect of ipratropium was delayed for 1 to 2 hr. Fenoterol 100 micrograms produced approximately half the degree of improvement in FEV1 and V50 compared with 200 micrograms of fenoterol. The addition of 40 micrograms of ipratropium to 100 micrograms of fenoterol resulted in bronchodilation equivalent to 200 micrograms fenoterol and was associated with a more prolonged effect than fenoterol 100 micrograms. Tremor was observed in two-subjects inhaling fenoterol 200 micrograms but was not observed with any other regimen. It is concluded that the combination of inhaled ipratropium and fenoterol is an effective bronchodilator in asthma, achieving efficacy similar to that of fenoterol alone but with fewer side effects.     

Asthma control can be maintained when fluticasone propionate/salmeterol in a single inhaler is stepped down

BACKGROUND: Asthma control is the goal of treatment, but little data exist to support treatment strategies for stepping down treatment once control has been achieved. OBJECTIVE: We assessed whether either the long-acting beta2-agonist or corticosteroid could be reduced without loss of asthma control once control had been attained with fluticasone propionate/salmeterol (FSC). METHODS: After 12 weeks of open-label treatment with FSC 250/50 microg twice daily, patients whose asthma was well controlled were randomized to FSC 100/50 microg twice daily or fluticasone propionate (FP) 250 microg twice daily. for 12 weeks. The primary endpoint was mean morning peak expiratory flow over the randomized study period. Secondary endpoints included symptom scores, rescue albuterol use, and asthma control. RESULTS: During open-label treatment, improvements from baseline were seen, and 435 of 641 patients (68%) achieved well controlled status during each of the last 4 weeks of this period. A total of 246 patients received FSC 100/50 microg twice daily and 238 FP 250 microg twice daily. The adjusted mean change in morning peak expiratory flow from the end of open-label treatment was -0.3 L/min for FSC and -13.2 L/min for FP (treatment difference, 12.9 L/min; 95% CI, 8.1-17.6; P<.001). Secondary efficacy endpoints also showed FSC 100/50 microg twice daily to be more effective than FP 250 microg twice daily alone. The majority of patients remained well controlled, but the proportion was higher with FSC. CONCLUSION: In patients achieving asthma control with FSC 250/50 microg twice daily, stepping treatment down to a lower dose of FSC 100/50 microg twice daily is more effective than switching to an inhaled corticosteroid alone.     

Intravenous versus nebulized terbutaline in patients with acute severe asthma; a double-blind randomized study

Twenty-three patients with acute severe asthma were treated in a randomized double-blind way by either intravenous terbutaline two times at an hour interval 6 micrograms/kg or inhaled terbutaline two times 0.1 mg/kg. Peak expiratory flow rate in percent of expected value rose from 89 L/min to 128 L/min (P less than .01) in the intravenous group and from 97 L/min to 122 L/min (P less than .02) in the inhalation group; this was comparable for both groups. PaO2 initially was 7.55 kPa in the intravenous group and rose by 1.4 after 60 minutes (P less than .02) and by 1.33 after 120 minutes (P less than .01). The mean PaO2 did not change in the inhalation group. The pulse rate and blood pressure did not vary significantly in either of the two groups. We conclude that both the intravenous and inhalational administration of terbutaline are effective in acute severe asthma, but that the intravenous route is possibly better for increasing PaO2.     

Effect of ��2-Adrenergic Receptor Polymorphism in Asthma Control of Patients Receiving Combination Treatment

Purpose

Combination treatment of inhaled corticosteroid (ICS) plus long-acting β2-agonist (LABA) is widely used as a maintenance regimen for the management of asthma. This study evaluated the effect of the β2-adrenergic receptor (ADRB2) polymorphism on lung function and asthma control with regular use of combination treatment of an inhaled ICS plus LABA.

Materials and Methods

43 Korean asthmatics who were symptomatic despite regular ICS use for at least 3 months were enrolled. For a 2-week run-in period, they received ICS (budesonide 800 µg/day) plus terbutaline (5 µg prn). as needed. During the 24-week active treatment period, they received budesonide 160 µg and formoterol 4.5 µg b.i.d. as maintenance and rescue medication. Pulmonary function and quality of life scores were monitored every 8 weeks; morning/evening peak expiratory flow meter (PEFR) was recorded daily. Patients were genotyped for ADRB2 Arg16Gly using single base extension methodology.

Results

During the run-in period, there were no significant between-group differences in lung function; after 8 weeks of active treatment, Arg/Arg patients had significantly higher forced expiratory volume in 1 secord (FEV₁) and maximal mid-expiratory flow (MMEF) (p = 0.023 and p = 0.021, respectively), and better asthma control and quality of life after 24 weeks (p = 0.016 and p = 0.028, respectively). During treatment, there was a greater improvement in morning/evening PEFR in Arg/Arg patients.

Conclusion

Asthmatic patients with the Arg/Arg genotype at codon 16 of ADRB2 achieve better asthma control with long-term regular use of combined budesonide and formoterol treatment, suggesting that the ADRB2 genotype may dictate choice of treatment strategy.     

A comparison of enprofylline and theophylline in the maintenance therapy of chronic reversible obstructive airway disease

To compare the efficacy and side effects of two xanthine derivatives in the maintenance therapy of reversible obstructive airway disease, 242 patients were assigned in randomized, double-blind fashion to receive either oral enprofylline or theophylline for 5 weeks in addition to their usual maintenance regimens. After a week of placebo xanthine therapy, enprofylline-treated patients received 150 mg of this drug twice daily (b.i.d.) for 3 days, 300 mg b.i.d. for 2 weeks, and 450 mg b.i.d. for 2 weeks. Theophylline was administered in identical doses, except that the final dosage increase was not made if plasma theophylline was 12 mg/ml or higher. At 300 mg b.i.d., both drugs significantly increased morning peak expiratory flow rate (PEFR), the mean increase above baseline being significantly higher for theophylline-treated patients (29.9 +/- 37.2 L/min) than for enprofylline-treated patients (17.4 +/- 36.9 L/min) (p = 0.023). At 450 mg b.i.d., improvement in morning PEFR was not significantly different between theophylline-treated (31.5 +/- 44.4 L/min) and enprofylline-treated groups (23.5 +/- 48.4 L/min). Evening PEFR, FEV1, and asthma symptom scores also improved significantly, demonstrating no significant difference between groups. The incidence of side effects was also similar between groups. We conclude that both enprofylline and theophylline offer useful bronchodilatation in the maintenance therapy of asthma, enprofylline, 450 mg b.i.d., being approximately equivalent to theophylline, 300 or 450 mg b.i.d.     

Inhaled budesonide aerosols in treatment of childhood asthma

Twenty-six children with chronic bronchial asthma, 19 boys and 7 girls, aged between 6 and 16 years with duration of asthma ranging from 1-12 years, were studied by a control, oral prednisolone 5 mg twice a day and inhaled budesonide 200 micrograms twice daily, each for 3 weeks. The clinical efficacy assessed daily by day and night symptom scores of cough, wheeze, sleep disturbance, limitation of activity, symptomatic inhaled terbutaline usage, daily morning and afternoon Peak Expiratory Flow Rate (PEFR), and weekly PEFR and Forced Expiratory Volume in 1 second (FEV1) in percent of predict, showed statistically significant improvement during the inhaled budesonide aerosol and oral prednisolone treatment periods in comparison with the control. No side effect was observed during any study periods.     

Exercise-induced anaphylaxis as a manifestation of cholinergic urticaria

Two patients presented with a history of exercise-induced hypotension associated with severe pruritus and either generalized urticaria or facial angioedema. Each patient was exercised under controlled conditions with use of a bicycle ergometer exerciser (900 KPM/min) for 20 to 30 min at 23 C. Each patient complained of generalized pruritus and then erupted in lesions typical of cholinergic urticaria. In one patient the lesions became confluent about the face and were followed by eyelid edema, lip swelling, and transient hypotension. Plasma histamine levels were elevated in each patient and reached a maximal level between 20 and 25 min. Neither patient had a change in forced expiratory volume in one second during the episode and detailed pulmonary function testing in one patient revealed no change in airway resistance, specific Conductance, forced expiratory vital capacity, or forced expiratory flow rates. One patient had a positive methacholine chloride (Mecholyl) skin test with satellite lesions, and the second patiem was skin-test negative. The skin test-positive patient, who was not hypotensioe when initially challenged, was strenuously exercised for 15 min/day. Progressively less severe reactions were seen associated with diminished histamine release, and the patient is now on a dailv exercise program, symptoms in the second patient are controlled with hydroxazine. Our results indicate that some patients with the exercise-induced anaphylactic syndrome are unusual examples of severe cholinergic urticaria. Furthermore, the utility q1 a regular exercise program as part of the management of some patients with cholinergic urticaria requires, further investigation.     

Spirometric and flow-volume curve analysis in rats,and optimal parameters for estimating obstructive impairment

We obtained flow-volume (F-V) curves in anesthetized rats by applying positive pressure on the body surface. To obtain the best curve, tracheal intubation with either a 12 or 13 gauge catheter and a surface pressure greater than 56 cmH₂O was necessary. Peak expiratory flow rate (PEFR) and forced vital capacity (FVC) were shown to be optimal parameters for estimation of bronchoconstriction induced by methacholine inhalation while FEV_0.05 (forced expiratory volume at 0.05 s) and FEV_0.10 were of limited usefulness for this purpose. The descending segment of the F-V curve consisted of two or three phases, with later phases shortened during bronchoconstriction. In conclusion, PEFR and FVC are optimal parameters for estimation of bronchoconstriction in rats. The decreases in PEFR and FVC may reflect constriction in large and smaller airways, respectively.     

Training perception of air flow obstruction in asthmatics

Eighteen asthmatics, aged 7 to 43, rated their breathing on a scale of 0 to 5 (worst to best). They were then informed of their predicted normal peak expiratory flow rate (PEFR) and instructed in proper PEFR measurement. Each subject then estimated and measured PEFR under physician supervision and subsequently rated breathing, estimated and measured PEFR at home twice daily recording the observations. At the initial home observation, the correlation coefficient (r1) between estimated and measured PEFR was .98. After ten observations r1 was greater than or equal to .97 in all 18 subjects (group mean .99). The r1 remained unchanged in those subjects who completed 28 and 42 observations. The r1 was .98 when only the observations where measured PEFR was less than 20% predicted were considered, demonstrating the validity of the relationship during abnormal expiratory flow. Multiple regression analysis showed no significant trend in the difference between estimated and measured PEFR over time after the initial observation. Of 12 subjects, 4 were significant underestimators of PEFR and 3 were overestimators, but the magnitude of either tendency was relatively small. The correlation coefficient (r2) between a subjective verbal breathing score and measured PEFR ranged from -.23 to .92 on an individual basis over the three time periods, with statistically significant group mean values of .37, .39, and .45 at 10, 28, and 42 observations, respectively. The r2 for observations where measured PEFR was abnormal was only .14 and not significant.(ABSTRACT TRUNCATED AT 250 WORDS)     

A New Inhalation Technique for Freon Aerosols

In a double-blind, cross-over, 2-day study 32 adult asthmatic patients compared the bronchodilating effect of 0.5 mg terbutaline sulphate aerosol, administered via a 10 cm tube extension attached to the actuator of a pressurized aerosol, with that of 0.2 mg salbutamol sulphate, administered by a conventional pressurized aerosol. New instructions for the inhalation technique were given for the terbutaline aerosol, dividing the actuation of the aerosol and the slow inhalation into two steps. The salbutamol aerosol was to be taken according to the instructions enclosed, i.e. coordinating the actuation of the aerosol and the inhalation.
The improvement in peak expiratory flow rate (PEFR)values was similar for the two treatments. Subjective assessments by the patients showed no differences between the two regimens.
As the effect seems to be equal, an aerosol actuator furnished with a tube extension, with no strict demands of synchronizing the actuation of the aerosol and the inhalation, could be a suitable alternative treatment in patients who find self-administration with conventional asthma aerosols difficult.