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Biomedical subjects

M Turpeinen

Publications and source records attributed to M Turpeinen.

At least 19 recordsLinked to original sources

Reference values for respiratory system impedance by using impulse oscillometry in children aged 2-11 years.

The forced oscillation technique makes it possible to evaluate the mechanical properties of the respiratory system with a minimum of cooperation. The method is therefore especially useful in children. Impulse oscillometry (IOS) is a commercially available version of this technique. There is, as yet, limited information on reference values for IOS in children. The aim of this study was to extend the reference values for IOS variables and to study their correlation with height, weight and age in healthy children. A sample (n = 360) of children (age 2.1-11.1 years) was measured by using impulse oscillometry (IOS; Jaeger, Würzburg, Germany). The sample was based on children attending kindergarten in Finland and children attending primary school in Sweden. Measurements of respiratory resistance (Rrs) and reactance (Xrs) at 5, 10, 15 and 20 Hz, total respiratory impedance (Zrs) and the resonance frequency (Fr) were made. All variables were related to body height. Most of them were also weakly related to weight. Reference equations for children (height 90-160 cm) are presented.

Age Factors↗

Induced sputum in children with newly diagnosed mild asthma: the effect of 6 months of treatment with budesonide or disodium cromoglycate.

BACKGROUND: There are few controlled studies on the effects of anti-inflammatory treatment on airway inflammation in newly diagnosed childhood asthma. METHODS: Sixty children with newly diagnosed mild persistent asthma, 5-10 years of age, and 17 healthy control subjects were studied. Asthmatic children were randomized into an open study with two treatment groups: (1) budesonide 400 microg twice daily for 1 month, 200 microg twice daily for 5 months and (2) disodium cromoglycate (DSCG) 10 mg three-times daily for 6 months. All exacerbations were treated with budesonide 400 microg twice daily for 2 weeks. Symptoms and lung function were recorded throughout the study. RESULTS: Sputum induction was safe and the overall success rate was 71%. This improved with age and decreased after treatment. At baseline, the asthmatic children had more eosinophils in blood (0.26 vs 0.18 x 10(9)/l, P = 0.03) and sputum (1.1 vs 0.0 %, P = 0.0001) than the control subjects. The numbers of sputum eosinophils correlated with bronchial responsiveness (R = -0.58, P = 0.0002). Eosinophils were higher in children with atopic asthma than with nonatopic asthma (P < 0.0001), and in children with a history wheezing than in children without wheezing (P = 0.02). Six months of budesonide treatment, but not of DSCG, improved lung function (P = 0.007), decreased symptoms (P = 0.007) and sputum eosinophils (P = 0.003). The effects of budesonide were pronounced in children with intense sputum eosinophilia (>3%). CONCLUSION: Sputum eosinophilia is present in children with newly diagnosed mild persistent asthma. Treatment with inhaled budesonide, but not with DSCG, decreases sputum eosinophils along with clinical and functional improvement.

Asthma↗

Concurrent cereal allergy in children with cow's milk allergy manifested with atopic dermatitis.

BACKGROUND: There is increasing consensus about the significance of food allergens in the pathogenesis of atopic dermatitis (AD) in infancy and childhood, with cow's milk and egg accounting for most of the reactions. Previous studies have indicated that multiple food sensitization, such as cereals, is very common in patients with cow's milk allergy (CMA). Evidence is lacking, however, as to its clinical relevance. OBJECTIVE: The purpose of this study was to determine the concurrent occurrence of cereal allergy among children with challenge-proven CMA who have residual symptoms, such as AD and/or gastrointestinal symptoms, during cow's milk elimination diet. Further, we sought to evaluate the utility of patch testing in prescreening foods other than cow's milk behind allergic symptoms in children. METHODS: The study population comprised 90 children, aged from 2.5 to 36 months (mean 1.1 years), with challenge-proven CMA. As a result of residual symptoms during meticulous cow's milk elimination diet (AD: n=80, and gastrointestinal: n=10), the children were put on a cereal elimination diet (oats, wheat, rye, and barley) and skin prick tests (SPT) and patch testing with cereals were performed. Open cereal challenge was performed to confirm cereal allergy. RESULTS: Cereal challenge was positive in 66 (73%) of the children with CMA. Of them, 17% reacted with immediate reactions and delayed-onset reactions were seen in 83% of the children. SPT was positive in 23%, patch test in 67%, and either SPT or patch test was positive in 73% of the children with cereal allergy. SPT gave the best positive predictive value, whereas SPT together with patch test gave the best negative predictive value. CONCLUSIONS: Residual symptoms, such as eczema or gastrointestinal symptoms in CMA children may be a sign of undetected allergy to other food antigens. SPT with cereals aids in diagnosing cereal allergy in small children, especially when used together with patch testing.

Animals↗

Exhaled nitric oxide rather than lung function distinguishes preschool children with probable asthma.

BACKGROUND: Respiratory function and airway inflammation can be evaluated in preschool children with special techniques, but their relative power in identifying young children with asthma has not been studied. This study was undertaken to compare the value of exhaled nitric oxide (FE(NO)), baseline lung function, and bronchodilator responsiveness in identifying children with newly detected probable asthma. METHODS: Ninety six preschool children (age 3.8-7.5 years) with asthmatic symptoms or history and 62 age matched healthy non-atopic controls were studied. FE(NO) was measured with the standard online single exhalation technique, and baseline lung function and bronchodilator responsiveness were measured using impulse oscillometry (IOS). RESULTS: Children with probable asthma (n=21), characterised by recent recurrent wheeze, had a significantly higher mean (SE) concentration of FE(NO) than controls (22.1 (3.4) ppb v 5.3 (0.4) ppb; mean difference 16.8 ppb, 95% CI 12.0 to 21.5) and also had higher baseline respiratory resistance, lower reactance, and larger bronchodilator responses expressed as the change in resistance after inhalation of salbutamol. Children with chronic cough only (n=46) also had significantly raised mean FE(NO) (9.2 (1.5) ppb; mean difference 3.9 ppb, 95% CI 0.8 to 7.0) but their lung function was not significantly reduced. Children on inhaled steroids due to previously diagnosed asthma (n=29) differed from the controls only in their baseline lung function. The analysis of receiver operating characteristics (ROC) showed that FE(NO) provided the best power for discriminating between children with probable asthma and healthy controls, with a sensitivity of 86% and specificity of 92% at the cut off level of 1.5 SD above predicted. CONCLUSIONS: FE(NO) is superior to baseline respiratory function and bronchodilator responsiveness in identifying preschool children with probable asthma. The results emphasise the presence of airway inflammation in the early stages of asthma, even in young children.

Airway Resistance↗

Controlled trial of dexamethasone in neonatal chronic lung disease: an 8-year follow-up of cardiopulmonary function and growth.

AIM: To evaluate the long-term effects of postnatal dexamethasone treatment in high-risk infants of very low birthweight. METHODS: The study included 16 children aged 7.8 to 9.2 y who had been born very prematurely at gestational ages of 24-29 wk and with birthweights of < 1500 g and who had participated in a randomized study of dexamethasone or placebo treatment in ventilator-dependent infants at 10 d of age. Flow-volume spirometry, impulse oscillometry, skin-prick tests and Doppler echocardiography were carried out at school age, and respiratory morbidity and overall neurological outcome evaluated. Controls were 18 non-atopic children born at term, tested for lung function. RESULTS: No significant differences were found in respiratory morbidity at school age between the dexamethasone (n = 8) and placebo (n = 8) groups. Six of the 16 children had moderate to severe neurosensory impairments, but all were able to walk without support and attended primary school. In prematurely born children, standardized height was significantly less than that in controls, but between the two study groups, no significant differences existed in somatic growth. Atopy was uncommon: skin-prick tests were positive in only one child in the placebo group. In the dexamethasone group, forced vital capacity adjusted to height was significantly higher than that in the placebo group, but impairment of basic lung function and bronchial obstruction was evident in both study groups. No hypertrophic cardiomyopathy was apparent, and non-invasive measurements of pulmonary arterial pressure did not reveal any significant difference between the study groups. CONCLUSION: In very low-birthweight children, high respiratory morbidity and neurological impairment continued until school age. Neonatal dexamethasone treatment at school age was not associated with any detectable adverse effects on somatic growth, or pulmonary or cardiac function.

Anti-Inflammatory Agents↗

Determinants of respiratory system input impedance and bronchodilator response in healthy Finnish preschool children.

In order to study the determinants of respiratory system impedance and bronchodilator response in preschool children, a sample (n = 109) of healthy children (age 2.1-7.0 years) attending kindergarten was measured by using the impulse oscillometry. Their selection was based on a standardized questionnaire, negative skin prick test results and clinical examination, and sufficient cooperation. Triple measurements of respiratory resistance (Rrs) and reactance (Xrs) at 5, 10, 15 and 20 Hz, total respiratory impedance (Zrs), the resonance frequency (Fr) and the frequency dependence of resistance (dRrs/df) were performed, to determine individual mean values. Measurements were repeated after inhalation of 300 microg salbutamol (n = 89) or placebo (n = 19). At the baseline, Zrs and Rrs5-20 showed negative, and Xrs5-20, Fr and dRrs/df positive correlations with age, height and weight. However, logarithmic transformed height was the best independent variable for the regression equations of all the oscillometric variables. After inhalation of placebo, none of the oscillometric variables changed significantly. In the salbutamol group, the mean (SD) change in Rrs5 was -0.187 (0.124) kPa l(-1) s(-1) and -19.2 (10.2)%, corresponding to a lower reference limit of -36.9%. Both the within-test and between-test repeatabilities for the measurement of respiratory resistance were acceptable, for Rrs5 the coefficients of variation being 6.2 and 6.1%, respectively. As the overall success rate in our sample was high (89%), the forced oscillation technique seems to be a useful method in assessing respiratory function and bronchial lability in preschool children.

Administration, Inhalation↗

Effect of inhaled budesonide therapy on lung function in schoolchildren born preterm.

We investigated the effect of inhaled glucocorticoid (GC) on bronchial obstruction and on bronchial lability in schoolchildren born preterm. Twenty-one children with bronchial obstruction, increased responsiveness to a beta2-agonist, and/or increased diurnal variation in peak expiratory flow (PEF) were selected for an open longitudinal study of the value of inhaled GC. None of these children had an earlier diagnosis of asthma or current GC treatment. Eighteen children with median (range) birth weight 1025 (640-1600) g and gestational age 28 (24-35) weeks, age at study 10.1 (7.7-13) years, were treated with inhaled budesonide in initially high (0.8 mg m(-2) day(-1) for 1 month) and subsequently lower dose (0.4 mg m(-2) day(-1) for 3 months). Daily symptom scores were recorded. Spirometric values were measured in the clinic at the beginning and end of each treatment period. At home, children used a data storage spirometer. After treatment with budesonide for 4 months, spirometric values in the clinic did not significantly change. The median forced expiratory volume in 1 sec (FEV1) was 74% of predicted both at entry and after budesonide treatment. However, the median number of > or = 20% diurnal change in PEF values at home decreased during treatment. According to the present study, inhaled budesonide for 4 months had no significant effect on basic lung function but may decrease bronchial lability in schoolchildren born preterm.

Administration, Inhalation↗

Acceptability, reproducibility, and sensitivity of forced expiratory volumes and peak expiratory flow during bronchial challenge testing in asthmatic children.

OBJECTIVES: To compare the acceptability, reproducibility, and sensitivity of spirometric outcome measures of airway caliber during challenge testing in children. DESIGN: FEV(1), forced expiratory volume in 0.75 s, forced expiratory volume in 0.5 s, and peak expiratory flow (PEF) were recorded during stepwise dosimetric histamine challenge tests. The responses were compared, and the reproducibility at baseline and from duplicate measurements at each challenge step was determined. PATIENTS: One hundred five children with newly diagnosed asthma, aged 5 to 10 years. RESULTS: Compared to PEF, FEV(1) showed better baseline reproducibility (p = 0.002) and higher sensitivity (p < 0.0001) during challenge testing, determined as the change normalized to the baseline variation, while the forced expiratory volumes were not significantly different in these respects. During challenge testing in subjects with acceptable flow-volume tracings, paired recordings of FEV(1) agreed within 0.1 L in 85% and within 0.2 L in 93% of measurements. During challenge testing, the reproducibility of FEV(1) measurements was not better than that of the other indexes. Failure to exhale long enough precluded the use of FEV(1) in 16 of the children, particularly the youngest children. CONCLUSIONS: The results demonstrated that the recently published guidelines for FEV(1) measurements during challenge tests can be applied to children. During challenge tests in asthmatic children, the advantage of the shorter fractions of forced expiratory volume was that they were more often acceptably recorded than FEV(1), while they showed as good reproducibility and were also equally sensitive in assessing changes in airway obstruction.

Asthma↗

Nebulization of a suspension of budesonide and a solution of terbutaline into a neonatal ventilator circuit.

METHODS: The amount of nebulized budesonide and terbutaline delivered through an endotracheal tube (ETT) was measured in vitro using a test lung and filters in a neonatal ventilator circuit. Budesonide suspension (1 mg) was used in a concentration of 0.5 mg/mL and terbutaline solution (5 mg) in a concentration of 2.5 mg/mL. RESULTS: The median amount of terbutaline deposited on the inspiratory filters was significantly higher than that of budesonide: 0.4% vs 0.3% of the nominal doses with the nebulizer connected 8 cm upstream of the ETT and nebulization performed in a constant output mode (setup A), and 2.8% vs 1.0% with the nebulizer connected directly to the ETT and nebulization performed in a breath-synchronized mode (setup B) (p < 0.05 for both). The corresponding amounts of drug deposited on the waste filters with setup A were 19.2% for terbutaline and 12.6% for budesonide, and with setup B 16.2% for terbutaline and 6.2% for budesonide (p < 0.05 for both). CONCLUSIONS: The ratio between drug delivery to the inspiratory and waste filters, describing the relationship between lung deposition and wastage of drug to the ventilator circuit, was setup-dependent but not drug-dependent. The ratio with setup A was 0.02 for both budesonide and terbutaline. The respective ratios were significantly (p < 0.05) higher for budesonide (0.16) and for terbutaline (0.17) with setup B. The differences in the delivered doses of the two drugs through the ETT seems to be a function of both the drug formulation and the nebulizer-ETT setup. With the nebulizer connected directly to the ETT and nebulization in breath-synchronized mode, the differences between the two drugs were enhanced, compared with the nebulizer connected upstream of the ETT and nebulization in constant output mode. The results indicate that a solution is superior to a suspension in terms of drug delivery through an ETT.

Aerosols↗

CYP2B6 and CYP2C19 as the major enzymes responsible for the metabolism of selegiline, a drug used in the treatment of Parkinson's disease, as revealed from experiments with recombinant enzymes.

In view of conflicting data in the literature regarding the enzyme(s) responsible for metabolism of selegiline, a drug used in the treatment of Parkinson's disease, investigations were carried out in vitro using the human cytochrome P450 enzymes CYP1A1, CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1, and CYP3A4 recombinantly expressed in yeast to elucidate the enzyme specificity in selegiline metabolism. In the yeast microsomes used, desmethylselegiline and levomethamphetamine were formed from selegiline at significant rates. The highest contribution to the hepatic clearance of selegiline was calculated to be exerted by CYP2B6 (124 l/h) CYP2C19 (82 l/h), whereas CYP3A4 (27 l/h) and CYP1A2 (21 l/h) were of less importance. Antibodies against CYP2B6 inhibited metabolism of selegiline in microsomes containing CYP2B6 but not in microsomes without significant amounts of the enzyme. In contrast to previous reports, we could not find any role for CYP2D6 in the metabolism of selegiline. The data strongly indicate that the high extent of interindividual variation seen in vivo for selegiline clearance is caused by the metabolism of the compound by the highly polymorphic CYP2B6 and CYP2C19.

Antiparkinson Agents↗

Reproducibility of home spirometry in children with newly diagnosed asthma.

We evaluated the reproducibility of home spirometry in 110 children aged 5-10 years with newly diagnosed asthma according to the criteria proposed by the American Thoracic Society (level of reproducibility < or = 5%). Flow-volume spirometry was performed in the clinic. Spirometric values were then monitored twice daily at home for 24 days (mean), using a novel device, the Vitalograph(R) Data Storage Spirometer (Vitalograph, Ltd., Buckingham, UK). During this period, the mean (SD) compliance in performing the spirometric tests was 94% (7). In the whole study population, the mean (SD) percentage of reproducible spirometric measurements was 77% (17), although there was wide individual variation (range, 21-100%). In the 5-6-year age group (n = 51), the mean (SD) percentage of reproducible spirometric values was 72.8% (18.6), in the 7-8-year group (n = 38) 77.1% (13.8), and in the 9-10-year group (n = 21) 84. 5% (13.7) analysis of variance, P = 0.02). We conclude that most of the children aged 5-10 years could perform reproducible spirometric tests during home monitoring, although there was wide individual variation. Younger children were less likely to perform reproducible tests than older children. However, a considerable proportion of the measurements (23%) did not meet the criteria of acceptable reproducibility. In order to improve the quality of home monitoring, nonreproducible measurements should be excluded from the calculations.

Anti-Asthmatic Agents↗

Evaluation of pulsed and breath-synchronized nebulization of budesonide as a means of reducing nebulizer wastage of drug.

The aim of this open, randomized, crossover study was to compare the inhaled mass of budesonide suspension delivered by nebulization, using constant output, breath-synchronized, or pulsed jet nebulization techniques. The inhaled mass was defined as the amount of drug deposited on a filter between the inspiratory port of the nebulizer and the face mask or mouthpiece used by the subjects. The breath-synchronized nebulization delivered aerosol during the whole inspiration, whereas the pulsed nebulization was adjusted to deliver aerosol for up to 1 sec from the start of inspiration. Budesonide suspensions, 2 mL of 0.5 mg mL(-1), or 2 mL of 0.25 mg mL(-1), in single-dose respules, were used (AstraZeneca R&D Lund, Lund, Sweden). Eleven children (7 boys, age range 2.5-5.8 years) with either a clinical suspicion or a confirmed diagnosis of asthma and 11 healthy adolescents and adults (6 male, age range 13-52 years) were enrolled. With constant output nebulization, the median inhaled mass of budesonide was about 17.6% (range 9.6-21.2%) of the nominal dose (i. e., dose of drug in the respule per label claim) in adolescents and adults, and 18.1% in children (15.7-21.4%). With pulsed nebulization the median inhaled mass increased to 23.4% (22.0-28.1%) in children and to 32.8% (24.8-38.0%) in adolescents and adults (P < 0.001). With breath-synchronized nebulization median inhaled mass increased to 30.1% (21.7-28.1%) in children, but was unchanged (30.8%, 27.0-38. 0%) in adolescents and adults. The mode of nebulization (i.e., constant or breath-synchronized) had a statistically significant effect on the inhaled mass in children and adolescents or adults (P < 0.001). There was a statistically significant difference in inhaled mass between the breath-synchronized and pulsed nebulization in children only (P < 0.05). The results support the use of breath-synchronized but not pulsed nebulization with conventional nebulizers. The results of pulsed nebulization in children warrants further clinical studies.

Adolescent↗

Lung function measured by the oscillometric method in prematurely born children with chronic lung disease.

Premature birth is related to a chronic respiratory morbidity, which may persist until school-age. In these children, the forced oscillation technique would be suitable for evaluation of lung function even at preschool age, since it requires only minimal patient cooperation. In order to investigate the oscillometric findings related to premature birth, using the oscillation technique and conventional lung function methods 49 school-aged children born prematurely with (n=15) or without (n=34) chronic lung disease (CLD), and 18 healthy children born at full term were studied. Children with CLD had higher respiratory resistance (Rrs,5) and lower reactance (Xrs,5) than prematurely born children without CLD or healthy controls. Both Rrs,5 (r=-0.55, p<0.0001) and Xrs,5 (r=0.76, p<0.0001) were significantly associated with forced expiratory volume in one second (FEV1), the agreement with spirometry being better in Xrs,5 than in Rrs,5 (p=0.02). Rrs,5 was significantly related to airway resistance (Raw) measured by body plethysmography (r=0.63, p<0.0001), but underestimated resistance at high values of Raw. There was no significant relationship between the pulmonary diffusing capacity and the oscillometric findings. Compared to conventional methods, the oscillometric method yields concordant information on the severity of lung function deficit in children born prematurely, with or without chronic lung disease. In these children, the oscillometric findings are probably due to peripheral or more widespread airway obstruction. As conventional methods are not usually suitable for preschool children, oscillometry may serve as an alternative for early evaluation of chronic lung disease among children with premature birth in clinical or research settings.

Analysis of Variance↗

Markers of collagen metabolism and insulin-like growth factor binding protein-1 in term infants.

AIM: To study the relation between fetal growth and markers of collagen metabolism and insulin-like growth factor binding protein-1 (IGFBP-1) in term infants. METHODS: Cord vein plasma was obtained from 67 term infants of gestational age 37.1-41.7 weeks (39 appropriate for gestational age (AGA), 11 large for gestational age (LGA; relative birth weight >/= 2.0 SD), and 17 small for gestational age (SGA; relative birth weight </= -2.0 SD)) for analysis of markers of metabolism of collagen type I (PICP and ICTP) and III (PIIINP) and of IGFBP-1. RESULTS: Negative correlations existed between gestational age and PICP (r = -0.294, p = 0.0158), ICTP (r = -0.338, p = 0.0052), and PIIINP (r = -0.432, p = 0.0003). These correlations were also found in SGA infants (all p < 0.05). IGFBP-1 showed negative correlations with birth weight and relative birth weight (r = -0.644, p = 0.0001, and r = -0.693, p = 0.0001 respectively) but not with gestational age (p>0.05). CONCLUSIONS: In the term fetus, collagen metabolism is primarily dependent on maturity and not on intrauterine growth status, whereas IGFBP-1 reflects intrauterine growth independently of maturity.

Biomarkers↗

Intraindividual variability of infant whole-body plethysmographic measurements: effects of age and disease.

The intraindividual variability of whole-body plethysmographic measurements was studied in a large series of consecutive infants (N = 144), divided into two groups: a group of infants born very prematurely (PM, N = 63), with (N = 28) or without (N = 35) a history of bronchopulmonary dysplasia (BPD), and a group of infants with persistent respiratory symptoms (PRS, N = 81), i.e., wheezing (N = 53) or cough (N = 28). The intraindividual variability was determined within each test and between tests, separated by a 10-min interval. In both study groups, the between-test variability was significantly larger than that within tests. Expressed as the median coefficient of variation (CV), the between-test repeatabilities in the PRS group were 8.0% for thoracic gas volume (TGV), 17.5% for airway resistance (Raw), and 18.4% for specific airway conductance (sGaw), and in the PM group, 8.9% for TGV, 20.4% for Raw, and 20.7% for sGaw. However, the individual range of CVs was large, ranging from 3 to 19% for TGV and from 5 to 55% for sGaw. With respect to TGV, the difference between the groups was statistically significant (P = 0.03). In infants with a history of BPD, there was also a significant negative age dependency in CVs of sGaw (r = -0.50, P = 0. 009), showing larger variation among younger individuals. The presenting symptom (wheezing or cough) in the PRS group did not influence the measurement variability significantly, and neither did the degree of bronchial obstruction. We conclude that on a group basis, the repeatability of infant body plethysmographic measurements may be satisfactory for scientific studies demonstrating pharmacodynamic effects; however, the intraindividual measurement variability should be reported for each test conditions and for infant groups in each study. Due to the large range in individual variation and the influence of age and disease processes on the variation, for an individual child there is only questionable benefit from a given measurement, unless the intrasubject, between-test variability is assessed individually before interventions, such as a bronchodilation test.

Bronchopulmonary Dysplasia↗

Metered dose inhaler add-on devices: is the inhaled mass of drug dependent on the size of the infant?

Limited cooperation and low tidal volumes in infants make aerosol therapy difficult. We measured the amount of drug delivered from two baby spacer devices especially developed for use in infants. Designed as a randomized crossover study, aerolized budesonide from a pressurized metered dose inhaler (pMDI) was collected in the inspiratory filter interposed between the face mask and the spacer in 13 infants aged from 2 to 19 months old. The study was performed in connection with pulmonary function testing with a plethysmograph, and the children were sedated with cloral hydrate. Two small-volume baby spacer devices were used: a Babyhaler spacer (GlaxoWellcome, Hertfordshire, UK) made of polycarbonate with a volume of 350 mL and a built-in dead space of 40 mL and a NebuChamber spacer (AstraZeneca, Lund, Sweden) made of stainless steel with a volume of 250 mL and no dead space. Budesonide delivery from the NebuChamber was significantly higher than from the Babyhaler: 38.2% (range, 28.3%-47.5%) of the nominal dose versus 12% (range, 3.3%-21.25%) of the nominal dose of 400 micrograms of budesonide (P = 0.002). The inhaled mass of budesonide from the Babyhaler correlated significantly with skin surface area (r = 0.68, P = 0.018), weight (r = 0.66, P = 0.019), height (r = 0.69; P = 0.017), tidal volume (r = 0.82; P = 0.004), and minute volume (r = 0.67; P = 0.019). No correlations were found between these variables and the inhaled mass of budesonide from the NebuChamber. The results indicate that the design of the NebuChamber spacer affords stable drug delivery in infants and that a large variability in the inhaled mass of drug may be found when infants are inhaling from different baby spacers.

Administration, Inhalation↗

The conventional ultrasonic nebulizer proved inefficient in nebulizing a suspension.

A study was undertaken to compare the amount of nebulized budesonide suspension and nebulized terbutaline sulphate solution inhaled by healthy adult subjects when conventional jet and ultrasonic nebulizers were used. Ten healthy subjects (5 male; age range, 16-52 years) used two conventional nebulizers: the Spira Elektro 4 jet nebulizer (Respiratory Care Center, Hämeenlinna, Finland) and the Spira Ultra ultrasonic nebulizer (Respiratory Care Center) in a breath-synchronized mode with each drug. The amount of drug inhaled, the inhaled mass, was defined as the amount of drug deposited on a filter between the inspiratory port of the nebulizer and the mouthpiece. The amount of budesonide and terbutaline sulphate was determined by reversed-phase high-performance liquid chromatography. Single-dose respules were used (0.5 mg of budesonide and 5.0 mg of terbutaline sulphate), and nebulization time up to the defined gravimetric output was recorded. The inhaled mass of budesonide varied depending on the nebulizer used, whereas the inhaled mass of terbutaline was unaffected by the choice of nebulizer. The median inhaled mass of budesonide was 31.4% of the nominal dose (i.e., dose of drug in the respule per label claim) with the Spira Elektro 4 and 9.9% with the Spira Ultra, whereas the median inhaled mass of terbutaline was 50% with the Spira Elektro 4 and 52% with the Spira Ultra. It appears that a suspension is generally more difficult to nebulize than a solution and that the budesonide suspension should not be used in conventional ultrasonic nebulizers.

Administration, Inhalation↗