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At least 19 recordsLinked to original sources

PubMed1980

A new inhalation technique for freon aerosols. Terbutaline aerosol with a tube extension in a 2-day cross-over comparison with salbutamol aerosol.

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.

Adult↗

PubMed1989

SAGE II aerosol data validation based on retrieved aerosol model size distribution from SAGE II aerosol measurements.

This paper describes an investigation of the comprehensive aerosol correlative measurement experiments conducted between November 1984 and July 1986 for satellite measurement program of the Stratospheric Aerosol and Gas Experiment (SAGE II). The correlative sensors involved in the experiments consist of the NASA Ames Research Center impactor/laser probe, the University of Wyoming dustsonde, and the NASA Langley Research Center airborne 14-inch (36 cm) lidar system. The approach of the analysis is to compare the primary aerosol quantities measured by the ground-based instruments with the calculated ones based on the aerosol size distributions retrieved from the SAGE II aerosol extinction measurements. The analysis shows that the aerosol size distributions derived from the SAGE II observations agree qualitatively with the in situ measurements made by the impactor/laser probe. The SAGE II-derived vertical distributions of the ratio N0.15/N0.25 (where Nr is the cumulative aerosol concentration for particle radii greater than r, in micrometers) and the aerosol backscatter profiles at 0.532- and 0.6943-micrometer lidar wavelengths are shown to agree with the dustsonde and the 14-inch (36-cm) lidar observations, with the differences being within the respective uncertainties of the SAGE II and the other instruments.

Aerosols↗

PubMed1977

Dose-response effects of albuterol aerosol compared with isoproterenol and placebo aerosols: response to albuterol, isoproterenol, and placebo aerosols.

Albuterol aerosol was an effective bronchodilator as reflected by indices of pulmonary function obtained from spirometry and flow volume curves; Compared with isoproterenol, there were minimal side effects even at the highest doses, and bronchodilation lasted significantly longer. In addition albuterol was successfully used by a patient with idiopathic hypertrophic subaortic stenosis who was unable to tolerate isoproterenol, as well as by some patients with idiosyncratic responses to isoproterenol; A few patients appeared to derive little benefit from either albuterol or isoproterenol.

Adolescent↗

PubMed2000

Aerosolized diuretics for preterm infants with (or developing) chronic lung disease.

BACKGROUND: Lung disease in preterm infants is often complicated with lung edema. OBJECTIVES: The aim of this review is to assess the risks and benefits of aerosolized diuretic administration in preterm infants with or developing chronic lung disease (CLD). Primary objectives are to assess effects on short term outcome (changes in need for oxygen or ventilatory support) and effects on long-term outcome. Secondary objectives are to assess changes in pulmonary mechanics and potential complications of therapy. SEARCH STRATEGY: We used the standard search method of the Cochrane Neonatal Review Group. We used the following keywords: ¿ or ¿ and , limited to and limited to or . We searched Medline (1966-1998), Embase (1974-1998) and the Cochrane Controlled Trials Register (CCTR) from the Cochrane Library (1998, Issue 4). In addition, we hand searched several abstract books of national and international American and European Societies. SELECTION CRITERIA: We included in this analysis trials in which preterm infants with or developing chronic lung disease and at least five days of age were all randomly allocated to receive an aerosolized loop diuretic. Eligible studies needed to assess at least one of the outcome variables defined a priori for this systematic review. Primary outcome variables included important clinical outcomes, and secondary outcome variables included pulmonary mechanics and potential complications of therapy. DATA COLLECTION AND ANALYSIS: We used the standard method for the Cochrane Collaboration which is described in the Cochrane Collaboration Handbook. Two investigators extracted, assessed and coded separately all data for each study, using a form that was designed specifically for this review. Any disagreement was resolved by discussion. We combined parallel and cross-over trials and, whenever possible, transformed baseline and final outcome data measured on a continuous scale into change scores using Follmann's formula. MAIN RESULTS: We identified eight studies which met selection criteria. Most studies focused on pathophysiological parameters and did not assess effects on important clinical outcomes defined in this review or the potential complications of diuretic therapy. No study assessed the amount of diuretic effectively delivered to the patient. Furosemide was the only diuretic used in the eight studies included in this review. Among preterm infants < 3 weeks of age developing CLD, not enough information is available to assess the effect of aerosolized furosemide on outcome or lung function. Among infants > 3 weeks with CLD, a single aerosolized dose of 1 mg/kg of furosemide may transiently improve pulmonary mechanics. Not enough information is available to assess the effect of chronic administration of aerosolized furosemide on oxygenation and pulmonary mechanics. REVIEWER'S CONCLUSIONS: In preterm infants > 3 weeks with CLD administration of a single dose of aerosolized furosemide improves pulmonary mechanics. In view of the lack of data from randomized trials concerning effects on important clinical outcomes, routine or sustained use of aerosolized loop diuretics in infants with (or developing) CLD cannot be recommended based on current evidence. More double-blinded randomized trials are needed (1) to analyze factors likely to affect the response to aerosolized furosemide, e.g. , washout period and delivery of furosemide to distal airways, and (2) to assess the effects of chronic administration of aerosolized furosemide on mortality, O2 dependency, ventilator dependency, length of hospital stay and long-term outcome.

Aerosols↗

PubMed1988

Aerosol deposition in the human lung: effect of high-frequency oscillation on the deposition characteristics of an inhaled nebulized aerosol.

1. Oral high-frequency oscillation (OHFO) may have important effects on aerosol deposition in the lungs. In order to investigate these, a technique was devised to measure regional deposition rates of a nebulized radiolabelled aerosol in the lungs during normal tidal breathing. 2. The effect of three frequencies of OHFO on pulmonary aerosol deposition rate (PADR) in four normal subjects and five patients with chronic airways obstruction (CAO) were assessed using the technique. 3. In separate experiments employing three normal subjects, the effect of OHFO was studied on the deposition rate of aerosol on the oropharynx and delivery apparatus, and on the amount and characteristics of aerosol inhaled by the subjects. 4. Total PADR was significantly reduced by OHFO at 8 Hz and 16 Hz in the normal subjects, and by all three frequencies of OHFO in the CAO patients. In the normal subjects, the regional distribution of aerosol deposition was unchanged, but in the CAO patients a larger proportion of total aerosol deposition occurred in peripheral lung. 5. OHFO reduced the oropharyngeal aerosol deposition rate, increased the loss of aerosol to the atmosphere before inhalation, and increased the deposition of aerosol on the delivery apparatus. The end result was a reduction in the amount of aerosol inhaled, and in the particle sizes measured at the mouthpiece. 6. We conclude that OHFO reduces the amount of aerosol inhaled, but may improve peripheral deposition of inhaled aerosol in patients with CAO. This effect may be of value in the clinical administration of nebulized drugs.

Aerosols↗

PubMed2001

Atmospheric secondary aerosol formation by heterogeneous reactions of aldehydes in the presence of a sulfuric acid aerosol catalyst.

Particle growth by the heterogeneous reaction of aldehydes was evaluated in 0.5 m3 Teflon film bags under darkness in the presence of background seed aerosols. The aldehydes used were as follows: glyoxal, butanal, hexanal, octanal, and decanal. To study acid catalyst effects on aldehyde heterogeneous reactions, one of the Teflon bags was initially filled with seed aerosols composed of ammonium sulfate-aerosol acidified with sulfuric acid. These results were compared to particle growth reactions that contained only ammonium sulfate as a background seed aerosol. The gas-phase aldehydes were then added to the Teflon bags. In selected experiments, 1-decanol was also added to the Teflon bags with aldehydes to clarify particle growth via a heterogeneous hemiacetal/acetal formation in the presence/absence of an acid catalyst. The particle size distribution and growth were measured using a scanning mobility particle sizer (TSI-SMPS), and the results were applied to predicting aerosol growth and size distribution changes by condensation and heterogeneous reactions. Aerosols created from the heterogeneous reactions of aldehydes were collected directly on an ungreased zinc selenide (ZnSe) FTIR disk (25 mm in diameter) by impaction. The ZnSe disks were directly analyzed for product functional groups inthe aerosol phase using a Fourier transform infrared (FTIR) spectrometer with a deuterated triglycine sulfate (DTGS) detector. Aerosol growth by heterogeneous aldehyde reactions proceeds via a hydration, polymerization process, and hemiacetal/acetal formation from the reaction of aldehydes with alcohols. These aldehyde heterogeneous reactions were accelerated in the presence of an acid catalyst, H2SO4, and led to higher aerosol yields than when H2SO4 was not present in the seed aerosol. The FTIR spectra obtained from the growing aerosol, also illustrated aldehyde group transformation in the particle phase as a function of the heterogeneous reaction. It was concluded that aldehydes, which can be produced by atmospheric photochemical reactions, can significantly contribute on secondary aerosol formation through heterogeneous reactions in the presence of an acid catalyst.

Aerosols↗

PubMed1987

Synergistic interaction of ozone and respirable aerosols on rat lungs. III. Ozone and sulfuric acid aerosol.

Previously we have demonstrated that a synergistic interaction, as evaluated by several biochemical, toxicological, and morphological responses of the lung, results from exposure of rats to ozone (O3) in conjunction with moderate concentrations of acidic, but not neutral, aerosols. To extend these studies, groups of rats were continuously exposed to either O3 or sulfuric acid aerosol alone, or to combinations of these pollutants. Pulmonary responses from these rats were measured by assay, after exposures for 6 hr to 7 days, of total lavageable protein content, total lung tissue protein content after 5, 7, or 9 days of exposure, or apparent collagen synthesis rates from lung tissue after 7 days of exposure. While the lavageable protein content from rats exposed for 3 days to 0.1 or 1.0 mg/m3 of sulfuric acid aerosol alone was not different from control values, significant elevations from control values were observed from groups exposed to 0.12, 0.20, or 0.64 ppm of O3. Synergy was demonstrated by this assay upon exposure of rats to 0.20 ppm of O3 in conjunction with 0.1, 0.5, or 1.0 mg/m3 of sulfuric acid aerosol. Similarly, the tissue protein content from rats exposed to 0.1 or 1.0 mg/m3 of sulfuric acid aerosol alone was indistinguishable from control values. Significant elevations from control values were observed by this assay from groups of rats exposed to 0.64 or 0.20 ppm of O3, and a synergistic interaction was demonstrated between 0.64 ppm of O3 and 1.0 mg/m3 of sulfuric acid aerosol. Furthermore, synergy was observed by quantification of increased total lung protein between 0.20 ppm of O3 + 40 micrograms/m3 and higher concentrations of sulfuric acid aerosol. Values of the lung collagen synthesis rate from rats exposed to 0.1, but not 1.0, 0.5, or 0.04 mg/m3 of sulfuric acid aerosol were significantly higher than values from lungs of control animals. Significant elevations from control values were also observed by this assay from groups of rats exposed to 0.64 or 0.20 ppm of O3. A synergistic interaction was demonstrated by the collagen synthesis rate assay between groups of rats exposed to 0.64 ppm of O3 + 0.20 mg/m3 and higher concentrations of sulfuric acid aerosol or between groups exposed to 0.20 ppm of O3 + 40 micrograms/m3 and higher concentrations of sulfuric acid aerosol. These results demonstrate synergy between O3 and sulfuric acid aerosol upon exposure to concentrations of each pollutant at or near peak hourly ambient levels in polluted urban atmospheres.

Aerosols↗

PubMed1986

Synergistic interaction of ozone and respirable aerosols on rat lungs. I. Importance of aerosol acidity.

A synergistic interaction, as defined by biochemical and morphological criteria, between ozone (or NO2) and respirable aerosols of ammonium sulfate or sulfuric acid has been described previously. Experiments in the present paper show that it is the acidity, not the sulfate content, of the aerosol that is responsible for such synergy; neutral aerosols of Na2SO4 or NaCl do not elicit synergistic effects when combined with ozone. Aerosol size (and, therefore, site of deposition in the lung) is also an important determinant of synergy with ozone; 0.5 micron mass median aerodynamic diameter (MMAD) aerosols are effective whereas 0.02 micron MMAD aerosols are not. The synergistic interaction between ozone and acidic aerosols could be demonstrated by biochemical and toxicological criteria in addition to those we have previously reported, for example increases in whole lung protein content and free (acid-soluble) proline content of lungs. A synergistic interaction has been demonstrated at concentrations of 0.64 ppm (1.3 mg/m3) of ozone and 1 mg/m3 of acid aerosol in this study. We conclude that acidity of an aerosol determines whether or not it interacts synergistically with ozone, and that an aerosol size that impacts maximally upon the alveolar duct region of the lung is most active with ozone.

Aerosols↗

PubMed2000

Aerosol delivery of amphotericin B desoxycholate (Fungizone) and liposomal amphotericin B (AmBisome): aerosol characteristics and in-vivo amphotericin B deposition in rats.

In the treatment or prophylaxis of invasive pulmonary aspergillosis, it may be attractive to administer the antifungal agent amphotericin directly to the pulmonary route via aerosol inhalation. In this study, we describe the aerosol characteristics of aerosolized nonliposomal amphotericin B (Fungizone) and liposomal amphotericin B (AmBisome), and the in-vivo aerosol deposition. Aerosols were generated with a Collison nebulizer. Aerosol amphotericin concentrations and mass median diameters were measured. In-vivo pulmonary deposition was evaluated by measuring amphotericin concentrations in lungs of treated rats. Whole body aerosol deposition was determined by measuring radioactivity in tissues of rats after treatment with radiolabelled liposomes. For Fungizone and AmBisome, aerosol amphotericin concentrations were 24.5+/-4.9 and 23.8+/-3.0 microg L(-1), respectively. The values for the median mass diameter were 1.38 and 2.26 microm for Fungizone and 2.43 and 1.97 microm for AmBisome. Amphotericin concentrations in lungs after 60-min nebulization of Fungizone or AmBisome were 24.2+/-6.4 and 21.7+/-2.6 microg g(-1), respectively. After nebulization of radiolabelled liposomes, no radioactivity was retrieved from tissues other than the lungs or the gastrointestinal tract. Nebulization of either Fungizone or AmBisome leads to respirable aerosols and results in a substantial lung tissue concentration of amphotericin and low systemic exposure of amphotericin B. Aerosol administration of either Fungizone or AmBisome may be an attractive approach to prevent or treat pulmonary aspergillosis.

Administration, Inhalation↗

PubMed1996

Aerosol production and aerosol droplet size distribution during mechanical ventilation (IPPV) with a new ultrasonic nebulizer.

Administration of drugs via the airway is increasingly practiced in ICU- and surgical patients. For this purpose, aerosols may be produced by either jet nebulization or ultrasonic droplet generation. In mechanically ventilated patients, aerosol delivery is often insufficient. The influence of the ventilatory pattern on nebulizer efficacy is poorly understood. In the present in vitro study we determined the efficacy of a new ultrasonic nebulizer in delivering aerosolized epoprostenol using defined ventilator settings. We determined aerosol delivery rates, the aerosol droplet size distribution and the impact of the connection tubing on drug delivery, applying adult and infant ventilation patterns. Aerosol production rates ranged from 0.28 to 0.57 ml per minute. Using an adult ventilator setting volume controlled ventilation (CMV) led to a higher aerosol production rate than pressure controlled ventilation (PCV) at identical tidal volumes and mean airway pressures (0.57 ml/min,CMV vs 0.39 ml/min, PCV). With an infant ventilator setting, nebulizer rates were lower than those found for the adult ventilator setting, but did not differ substantially between CMV and PCV mode (0.29 ml/min, CMV vs 0.28 ml/min, PCV). Aerosol delivery rates distal to the endotracheal tube changed according to aerosol production rates (adult mode: 0.18 ml/min, CMV vs 0.10 ml/min, PCV; infant mode: 0.03 ml/min, both CMV and PCV). In the infant ventilation mode, a higher percentage of the aerosol was trapped in the catheter mount as compared to the adult ventilation mode. Mass median droplet diameters for each of the four ventilator settings were almost identical (4.63 to 5.09 micron) and smaller than indicated in the product specifications (8 micron). Delivery rates and sizes of droplets delivered by the new ultrasonic nebulizer SUN 345(R) agree well with previously reported data from comparable settings using diverse nebulizer devices.

Adult↗

PubMed1982

Clinical aerosols II. Therapeutic aerosols.

The current uses of clinical aerosols such as water, saline, mucolytics, bronchodilators, cromolyn sodium, corticosteroids, and antimicrobials have been reviewed. The benefits of water, saline, and detergent aerosols continue to be surrounded by uncertainty and controversy. Aerosolized mucolytic and proteolytic agents have not been conclusively shown to be of substantial value in the improvement of respiratory disorders. Favorable bronchodilator therapy is achieved with aerosols of certain sympathomimetic and anticholinergic agents. However, successful therapy depends on the dose administered and the site of aerosol deposition in the lung. The prophylactic use of cromolyn sodium in patients with asthma is another useful application of aerosols. Topically active corticosteroid aerosols are increasingly being used since they may reduce risks of systemic effects from corticosteroids. Research on uncommonly aerosolized agents has widened the spectrum of therapeutic applications of aerosols.

Acetylcysteine↗

PubMed2000

Optical measurements of aerosol size distributions in Great Smoky Mountains National Park: dry aerosol characterization.

Aerosol size distributions were measured during the summertime 1995 Southeastern Aerosol and Visibility Study (SEAVS) in Great Smoky Mountains National Park using an Active Scattering Aerosol Spectrometer (ASASP-X) optical particle counter. We present an overview of the experimental method, our data inversion technique, timelines of the size distribution parameters, and calculations of dry accumulation mode aerosol density and refractive index. Aerosol size distributions were recorded during daylight hours for aerosol in the size range 0.1 < Dp < 2.5 microns. The particle refractive index used for the data inversion was calculated with the partial molar refractive index approach using 12-hr measured aerosol chemical composition. Aerosol accumulation mode volume concentrations ranging from 1 to 26 micron 3 cm-3 were observed, with an average of 7 +/- 5 micron 3 cm-3. The study average dry accumulation mode geometric volume median diameter was 0.27 +/- 0.03 micron, and the mean geometric standard deviation was 1.45 +/- 0.06. Using an internally mixed aerosol model, and assuming chemical homogeneity across the measured particle distribution, an average accumulation mode dry sulfate ion mass scattering efficiency of 3.8 +/- 0.6 m2 g-1 was calculated.

Aerosols↗

PubMed1991

Drug delivery via aerosol systems: concept of "aerosol inhaled".

The mass of aerosol inhaled is primarily a function of the patient's breathing pattern and the aerosol delivery system. Once inhaled, deposition is governed by factors related to the properties of the aerosol and the individual characteristics of the patient (e.g., particle size distribution, airway geometry, and residence time). This paper will center upon the actual generation and delivery of clinical aerosols by jet nebulizers and assess variability in aerosol delivery. Because of the practical difficulties in predicting nebulizer function from first principles, it will be advocated that nebulizer function be directly measured for each clinical situation. Terms like "nebulizer output", "efficiency", etc. are to be avoided. The following definition is proposed: "aerosol inhaled" represents that quantity of drug actually delivered by a given nebulizer for a defined breathing pattern and period of time. The concept of "aerosol inhaled" allows a direct comparison of the quantity of drug delivered by different nebulizer systems and adjustment of dose of a given therapeutic agent. Bench testing of aerosol systems and measurement of "aerosol inhaled" can be made in the laboratory if careful attention is paid to the relationship between laboratory conditions and actual use, including the particle distribution and the accuracy of a radiolabel in estimating the quantity of drug nebulized.

Administration, Inhalation↗

PubMed1972