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PubMed1990

Inhaler devices and the elderly.

This study compared the relative ease of use of the metered dose inhaler, the FO2 Inhalator and the Diskhaler by elderly subjects in a randomised cross over trial using placebo inhalants. Thirty-one nonasthmatic volunteers (average age 79.6 years) who lived independently in two residential homes for the elderly were recruited. One failed to complete the study. Subjects were taught to use the three inhaler devices in a randomly assigned sequence with a two week period elapsing between each training session. The Diskhaler device took longest to learn (16.5 minutes) and the Inhalator was significantly easier to learn to use than the other two (x2 = 40.3, p = 0.001). The Inhalator was preferred by 64%, metered dose inhaler by 25% and Diskhaler by 11% (p = 0.03). Problems in the use of each are described. The study found that the Inhalator was simple to use and was reliably self administered by older people. The metered dose inhaler was simple to use only for a minority who could accurately coordinate actuation and inhalation. The Diskhaler had no advantages in this age group.

Aged↗
PubMed1986

Fenoterol powder inhaler technique in children: influence of inspiratory flow rate and breath-holding.

The bronchodilator response after three different modes of inhalation of 0.2 mg fenoterol from a fenoterol powder inhaler was assessed in ten asthmatic children in a double-blind, placebo-controlled, cross-over study. There was a small, but statistically significant increase in response when the children inhaled as fast as possible, compared with very slow inhalations (16-19 l/min), but a breath-holding pause of 10 s after the inhalation had no significant effect on bronchodilation. Peak inspiratory flow through the inhaler, measured in 150 normal children aged 3.5-15 years, showed that all the children studied were able to generate a sufficient inspiratory flow to benefit from treatment with this inhaler. It is concluded that children using a fenoterol powder inhaler should be taught to inhale as fast as possible. They need not hold their breath after the inhalation.

Adolescent↗
PubMed1975

Inhaled corticosteroids compared with oral prednisone in patients starting long-term corticosteroid therapy for asthma. A controlled trial by the British Thoracic and Tuberculosis Association.

Inhaled beclomethasone dipropionate and inhaled betamethasone valerate have been compared with oral prednisone in the treatment of 75 patients with asthma who were starting long-term corticosteroids for the first time. Both of the inhaled corticosteroids controlled asthma as well as did oral prednisone in those who had responded to therapy in the initial period of the trial. A daily dose of 400 mug of inhaled drug was approximately equivalent to 7-5 mg daily of prednisone. Prednisone suppressed the adrenal response to tetracosactrin, whereas the mean responses in the groups receiving inhaled corticosteroids did not change significantly from pre-trial values. The 30% incidence of other systemic unwanted effects of prednisone contrasted sharply with the low incidence (5%) of symptomatic oropharyngeal candidiasis in the patients receiving inhaled corticosteroids. In a sample of 19 patients no change in exfoliative cytology was detected over the period of the trial nor was there any evidence of fungal colonisation of the bronchial tree. There was no difference between the three treatment groups in the number of antibiotic courses prescribed. The persistent production of sputum made no difference to the response to inhaled corticosteroids. Patients not on sodium cromoglycate did as well in the trial as those receiving sodium cromoglycate. Both inhaled beclomethasone dipropionate and inhaled betamethasone valerate have advantages over oral prednisone in the maintenance treatment of patients with asthma, but in the management of exacerbations systemic corticosteroids will usually be needed as a supplement to inhaled therapy.

Administration, Intranasal↗
PubMed1995

[Comparison by twin impinger of the distribution patterns of two beclomethasone dipropionate metered dose inhalers and of two spacer devices].

A Twin Impinger was used to assess the influence of the number of puffs on the distribution patterns of two commercially available beclomethasone dipropionate (BDP) metered dose inhalers, and the effects of two kinds of spacer devices were also compared. No difference was observed in the distribution pattern up to the 10th puff between the two metered dose inhalers. Clinically, the amount of BDP inhaled into the lungs is said to depend on the number of puffs taken, but in this study, there was a significant difference in the distribution pattern between these 2 inhalers. In the stage assumed to represent the oropharynx site, the distribution ratio of BDP was greater after administration with an Aldecin than with a Becotide inhaler. In contrast, in the stage assumed to represent the lung, the distribution ratio of BDP was greater with the Becotide inhaler. This result suggests that the amount of BDP inhaled in the lungs may vary between these two preparations. The effects of spacer devices were also investigated in 4 puffs. These spacer devices caused the distribution ratio in the stage assumed to represent the oropharynx to decrease by at least 90%, irrespective of the type of metered dose inhaler. This result suggests that spacer devices are useful in reducing local side effects in the oropharynx. In the stage assumed to represent the lung, the distribution ratio achieved with the Becotide inhaler with Volumatic was greater than that with the Aldecin with InspirEase. This study suggests that the best therapeutic effects can be expected from a combination of Becotide inhaler and Volumatic.

Beclomethasone↗
PubMed1995

Particle inhalability curves for humans and small laboratory animals.

Several inhalability curves for nose breathing in humans have been developed. No studies have been designed specifically to develop inhalability functions for animals, although it has been shown that pulmonary deposition of large particles (> 4-5 microns) via inhalation is minimal in laboratory animals [Raabe et al., Inhaled Particles VI, pp. 53-63. Pergamon Press, Oxford (1988)]. The logistic function was fitted to these animal deposition data of Raabe et al. (1988) to estimate an inhalability curve for laboratory animals. The logistic function was also fitted to the human data of Breysse and Swift [Aerosol Sci. Technol. 13, 459-464 (1990)] for comparison. The results suggest that ambient concentration is a good predictor (inhalability > 95%) of inhaled concentration for humans for particles < 11 microns dae. In small laboratory animals, however, the inhalable portion of the ambient concentration is predicted to be 95% for 0.7 microns dae particles but declines to 45% for 10 microns dae particles. It is, therefore, important to consider the effects of inhalability when estimating dose delivered to the target tissue in animals. In comparing delivered doses between animals and humans, adjusting for inhalability may change not only the magnitude of the difference but also which species is predicted to receive a greater delivered dose.

Air Pollutants↗
PubMed1994

Inhaled nitric oxide selectively decreases pulmonary vascular resistance without impairing oxygenation during one-lung ventilation in patients undergoing cardiac surgery.

BACKGROUND: Inhaled nitric oxide (NO), an endothelium-derived relaxing factor, is a selective pulmonary vasodilator. The authors investigated whether inhaled NO decreases pulmonary vascular resistance (PVR) while preserving hypoxic pulmonary vasoconstriction and whether it maintains or improves oxygenation in patients during one-lung ventilation. METHODS: In supine cardiac surgical patients with a normal mean pulmonary artery pressure (PAP) (< 25 mmHg, n = 10) or a moderately elevated PAP (25-35 mmHg, n = 10), one-lung ventilation was established with 80% oxygen and 20% nitrogen followed by the same gas mixture containing 20 ppm NO for 6 min. RESULTS: Inhaled NO decreased (P < 0.05) PAP from 30 +/- 2 to 27 +/- 2 mmHg in the patients with moderate pulmonary hypertension. Likewise, PVR decreased (P < 0.05) from 266 +/- 10 to 205 +/- 8 dyn.s.cm-5. The PAP and PVR did not change significantly after NO inhalation in the patients without pulmonary hypertension. All other hemodynamic variables remained unchanged after inhalation of NO in both groups. In the patients with pulmonary hypertension, the PAP and PVR returned to baseline after discontinuation of inhaled NO. Inhaled NO did not significantly change the arterial oxygen tension or venous admixture in either group of patients. Ventilation, airway pressure, tidal volume, and lung compliance also were unaffected by inhaled NO. CONCLUSIONS: This study demonstrates that 20 ppm inhaled NO is a selective pulmonary vasodilator in patients with moderate pulmonary hypertension secondary to cardiac disease who are undergoing one-lung ventilation. In contrast to what would be expected with intravenous vasodilators that inhibit hypoxic pulmonary vasoconstriction, inhaled NO does not increase the venous admixture or impair oxygenation.

Cardiac Surgical Procedures↗
PubMed1995

Inhalants in Peru.

In Peru, the prevalence and consequences of inhalant abuse appear to be low in the general population and high among marginalized children. Inhalant use ranks third in lifetime prevalence after alcohol and tobacco. Most of the use appears to be infrequent. Among marginalized children, that is, children working in the streets but living at home or children living in the street, the problem of inhalant abuse is a serious problem. Among children working in the streets but living at home, the lifetime prevalence rate for inhalant abuse is high, ranging from 15 to 45 percent depending on the study being cited. For children living in the streets, the use of inhalant is even more severe. As mentioned earlier in this chapter, most of these street children use inhalants on a daily basis. The lack of research on the problem of inhalant abuse is a serious impediment to development of intervention programs and strategies to address this problem in Peru. Epidemiologic and ethnographic research on the nature and extent of inhalant abuse are obvious prerequisites to targeted treatment and preventive intervention programs. The urgent need for current and valid data is underscored by the unique vulnerability of the youthful population at risk and the undisputed harm that results from chronic abuse of inhalants. Nonetheless, it is important to mention several programs that work with street children. Some, such as the Information and Education Center for the Prevention of Drug Abuse, Generation, and Centro Integracion de Menores en Abandono have shelters where street children are offered transition to a less marginal lifestyle. Teams of street educators provide the children with practical solutions and gain their confidence, as well as offer them alternative socialization experiences to help them survive the streets and avoid the often repressive and counterproductive environments typical of many institutions. Most of the children who go through these programs tend to abandon inhalant use as they mature out of street life.

Adolescent↗
PubMed2003

[Inhaled treatments delivery in children].

The most efficient method to deliver drugs to the lungs in children is the inhaled way. Its success depends on the characteristics of the aerosol, on those of the patient, and mainly on the inhalatory system. Before the age of 8 years, the most efficient system is the pressurised metered dose inhaler used together with a spacer device. Above this age, the use either of the pressurised metered dose inhaler, with a spacer device or a breath-actuated inhaler, or of a dry powder inhaler is discussed. Nebulisation is rarely indicated, except in cystic fibrosis. Demonstration with repeated medical instructions allows adequate inhalation technique. Inhaled treatments are efficient when used in diseases requiring this type of treatment, when several inhalers with different inhalatory techniques are not prescribed together, and when delivery is once or twice daily. At last, inhaled way is a new approach for different drugs with an extra-respiratory activity.

Administration, Inhalation↗
PubMed2002

[Multicenter prospective study of respiratory patient education and instruction in the use of inhalers (EDEN study)].

OBJECTIVES: To evaluate patients' knowledge of the inhalers they use and to assess the effect of knowledge acquired in an instruction session on correct technique. MATERIAL AND METHODS: Multicentric, prospective, descriptive study before and after one instruction session dealing with the technique to apply in using an inhaler: a pressurized canister, an inhalation chamber Autohaler, or one of two dry powder inhalers (the Turbuhaler or the Accuhaler). We studied 349 patients who used their inhalers regularly to treat their respiratory diseases. After assessing their theoretical knowledge of the airways (common), of the particular device they used, and their inhalation technique, we gave instruction in correct technique. Both types of knowledge were then evaluated 2 and 8 months after instruction. RESULTS: Before instruction, common theoretical knowledge was 3.2 (1) on a 6-point scale and knowledge of the device used was 2.7(1) on a 4-point scale. Technique was assessed as 77 (21) on a 100-point scale. After instruction both theoretical knowledge and technique improved significantly. Common knowledge after instruction was assessed as 5.1 (1) at 2 months and 5.2 (1) at 8 months; knowledge of the inhaler was 3.5 (0.6) and 3.6 (0.7), respectively. Technique was assessed at 95 (11) and 96 (11) at 2 and 8 months, respectively. CONCLUSIONS: The EDEN study demonstrates that knowledge of inhalers in a large sample of the population of respiratory disease patients in Spain, although acceptable, can be improved by an appropriate instruction program. After a standardized instruction program, correct use of all the inhalers studied was achieved. We believe that we thereby contribute to improving symptoms and quality of life of respiratory disease patients.

Administration, Inhalation↗
PubMed2003

Direct clinician-to-patient feedback discussion of inhaled steroid use: its effect on adherence.

STUDY OBJECTIVES: To evaluate whether direct feedback discussion on inhaled steroid use might influence subsequent adherence with this therapy. DESIGN AND SETTING: A 10-week, single-blind, randomized trial in asthma patients. Inclusion criteria included forced expiratory volume in 1 second <80%, one or more markers for low socioeconomic status, and the use of inhaled steroids. Inhaled steroid and beta-agonist use were electronically monitored. All patients received standard asthma care. The treatment group received direct clinician-to-patient feedback discussion on their inhaled steroid and beta-agonist use on all subsequent visits, whereas this information was withheld during the study period in the control group. MEASURES: 1) Mean weekly inhaled steroid adherence [(number of actuations/prescribed number of actuations) x 100]; 2) number of days with overuse of inhaled steroids; 3) 24-hour and nighttime albuterol use; 4) included forced expiratory volume in 1 second; and 5) Asthma Quality of Life Questionnaire total score. RESULTS: Ten treatment and nine control patients completed the study. Mean weekly inhaled steroid adherence over the first week was not significantly different in the treatment and control groups: 61 +/- 9% versus 51 +/- 5%, respectively. However, by the second week, adherence increased to 81 +/- 7% in the treatment group, whereas it decreased to 47 +/- 7% in the control group (P = 0.003). Adherence remained above 70% in the treatment group for the entire trial, but continued to decrease in the control group. Overuse of inhaled steroids was low in both groups. There were no group differences in any of the asthma outcomes. CONCLUSIONS: Direct clinician-to-patient feedback discussion on inhaled steroid use using electronic printouts did improve adherence in the short-term in asthma patients at high-risk for poor adherence.

Administration, Inhalation↗
PubMed2002

Patient perception and acceptability of multidose dry powder inhalers: a randomized crossover comparison of Diskus/Accuhaler with Turbuhaler.

This study was designed to provide information on correct use and preference to features and device handling of two multidose dry powder inhalers, the Diskus/Accuhaler and the Turbuhaler. A total of 169 powder-naive patients (mean age 40 years) with asthma or chronic obstructive pulmonary disease (COPD) were enrolled in a randomized crossover comparison of both inhalers. An effective use of either inhaler was assessed before (leaflet only) and after inhaler education. Ease of use especially during an attack and the presence of a dose counter were regarded as the most important features for an ideal inhaler. The percentage of correct handling maneuvers and the percentage of patients achieving 100% of correct maneuvers increased significantly (p < 0.001) after inhaler education in both devices, but percentage of correct use after the intervention was significantly higher for the Diskus/Accuhaler (92.6%) than for the Turbuhaler (89.8%; p = 0.036). Overall 60% of patients thought the Diskus/Accuhaler was preferable to the Turbuhaler (p < 0.001). The main reasons given were presence of a dose counter, perceived ease of use including ease of learning to use, design, and attached cover. Among those who preferred the Turbuhaler device, the main reason cited was small size, discreetness, and ease of holding. In the multivariate analysis, inhaler education (p = 0.005) and education level (p = 0.009) were significantly associated with the percentage of correct maneuvers. Age, sex, or tested inhaler showed no effect on appropriateness of the inhalation technique.

Administration, Inhalation↗
PubMed2002

Mass output and particle size distribution of glucocorticosteroids emitted from different inhalation devices depending on various inspiratory parameters.

Efficient inhalation therapy depends on successful delivery of the drug to the lung. The efficacy of drug delivery is not only influenced by the characteristics of the inhalation device, but also by the patient's handling of the device and by the inspiratory maneuver achieved through the device. We analyzed the output characteristics of three different chlorofluorocarbon (CFC)-free breath-actuated inhalers for inhaled glucocorticosteroids (BUD Turbohaler, FP Diskus/Accuhaler and HFA-BDP Autohaler, respectively). Mass output and particle size distribution of drug aerosol delivered by the inhalers were determined depending on different inhalation parameters in vitro using an Andersen cascade impactor. We found that, beside the peak inspiratory flow (PIF), other factors such as flow acceleration and inhalation volume also have significant effects on aerosol generation with respect to mass output and particle size distribution. Thus, these parameters should be taken into account when a suitable device for an individual patient is to be selected. The dependency on inspiratory parameters was most pronounced for the dry powder inhalers. The Turbohaler showed by far the highest variance in particle output (fine particle fraction ranging from 3.4% to 22.1% of label claim), whereas the Diskus was less dependent on variations in inhalation (10.6% to 18.5% of label claim). The most constant aerosol output was found for the Autohaler, which also released the highest fine particle fraction (43.1% to 56.6% of label claim).

Administration, Inhalation↗
PubMed2005

Comparison of the oropharyngeal deposition of inhaled ciclesonide and fluticasone propionate in patients with asthma.

Ciclesonide is a novel inhaled corticosteroid that is converted in the lungs to its active metabolite, desisobutyryl-ciclesonide (des-CIC). The aim of this study was to compare the deposition of ciclesonide, as well as its conversion to des-CIC, in the oropharyngeal cavity with fluticasone propionate (FP) following inhalation via hydrofluoroalkane-propelled metered-dose inhalers (HFA-MDIs). Eighteen asthmatics inhaled ciclesonide 800 microg followed by FP 1000 microg or vice versa in an open, randomized, 2-treatment, 2-sequence study design. The oropharynx was washed out immediately and at 15, 30, 45, and 60 minutes after inhalation. Samples were analyzed for ciclesonide, des-CIC, and FP using liquid chromatography with tandem mass-spectrometric detection. Concentration-time curves and area under the concentration-time curve (AUC) were calculated for each drug. Ciclesonide and FP were recovered in almost all samples. Within 60 minutes after inhalation, the amounts of both ciclesonide and FP decreased sharply, and low residual levels were detected after 30 minutes. des-CIC was detected in relatively low concentrations, with maximum concentration 30 minutes following inhalation. The AUC(0-60 min) for ciclesonide (250.4 nmol x h/L) and des-CIC (37.8 nmol x h/L) were found to be significantly lower compared with FP (636.2 nmol.h/L, P < .001). Approximately 50% less ciclesonide and 90% less metabolite were present in the oropharynx compared with FP. Less than 20% of the residual ciclesonide in the oropharynx was metabolized to des-CIC. These findings indicate that oropharyngeal deposition of ciclesonide is only half that of FP following inhalation from an HFA-MDI. Furthermore, there is little activation of ciclesonide to its active metabolite in the oropharynx, suggesting a decreased likelihood of inhaled ciclesonide-associated oropharyngeal side effects.

Administration, Inhalation↗
PubMed2005

Use of inhaled insulin in a basal/bolus insulin regimen in type 1 diabetic subjects: a 6-month, randomized, comparative trial.

OBJECTIVE: Despite the demonstrated benefits of glycemic control, patient acceptance of basal/bolus insulin therapy for type 1 diabetes has been slow. We investigated whether a basal/bolus insulin regimen involving rapid-acting, dry powder, inhaled insulin could provide glycemic control comparable with a basal/bolus subcutaneous regimen. RESEARCH DESIGN AND METHODS: Patients with type 1 diabetes (ages 12-65 years) received twice-daily subcutaneous NPH insulin and were randomized to premeal inhaled insulin (n = 163) or subcutaneous regular insulin (n = 165) for 6 months. RESULTS: Mean glycosylated hemoglobin (A1C) decreased comparably from baseline in the inhaled and subcutaneous insulin groups (-0.3 and -0.1%, respectively; adjusted difference -0.16% [CI -0.34 to 0.01]), with a similar percentage of subjects achieving A1C <7%. Although 2-h postprandial glucose reductions were comparable between the groups, fasting plasma glucose levels declined more in the inhaled than in the subcutaneous insulin group (adjusted difference -39.5 mg/dl [CI -57.5 to -21.6]). Inhaled insulin was associated with a lower overall hypoglycemia rate but higher severe hypoglycemia rate. The overall hypoglycemia rate (episodes/patient-month) was 9.3 (inhaled) vs. 9.9 (subcutaneous) (risk ratio [RR] 0.94 [CI 0.91-0.97]), and the severe hypoglycemia rate (episodes/100 patient-months) was 6.5 vs. 3.3 (RR 2.00 [CI 1.28-3.12]). Increased insulin antibody serum binding without associated clinical manifestations occurred in the inhaled insulin group. Pulmonary function between the groups was comparable, except for a decline in carbon monoxide-diffusing capacity in the inhaled insulin group without any clinical correlates. CONCLUSIONS: Inhaled insulin may provide an alternative for the management of type 1 diabetes as part of a basal/bolus strategy in patients who are unwilling or unable to use preprandial insulin injections.

Administration, Inhalation↗
PubMed2000

Early administration of inhaled corticosteroids for preventing chronic lung disease in ventilated very low birth weight preterm neonates.

BACKGROUND: Chronic lung disease remains a common complication amongst preterm infants. There is increasing evidence that inflammation play an important role in the pathogenesis of CLD. Due to their strong anti-inflammatory properties corticosteroids is an attractive intervention strategy. However, there are growing concerns regarding short and long term effects of systemic corticosteroids. Theoretically, administration of inhaled corticosteroids may allow for beneficial effects on the pulmonary system with a lower risk of undesirable systemic side effects. OBJECTIVES: To determine the impact of inhaled corticosteroids administered to ventilated very low birth weight preterm neonates in the first two weeks of life for the prevention of chronic lung disease(CLD). SEARCH STRATEGY: Systematic search in accordance with Cochrane Neonatal Review Group. Randomized and quasi-randomized trials were identified by searching MEDLINE, Embase, CINAHL, the Cochrane Library, reference lists of published trials and abstracts published in Pediatric Research. SELECTION CRITERIA: Randomized controlled trials of inhaled corticosteroid therapy initiated within the first 2 weeks of life in ventilated preterm infants with birth weight 1500 grams or less were included in this review. DATA COLLECTION AND ANALYSIS: Data regarding clinical outcomes including chronic lung disease at 28 days or 36 weeks corrected gestational age (CGA), mortality, combined outcome of death or CLD at 28 days of age and at 36 weeks CGA, the need for systemic corticosteroids, failure to extubate within 14 days and adverse effects of corticosteroids were evaluated. All data were analyzed using Revman 3.1. When possible, meta-analysis was performed using relative risk (RR), risk difference (RD), along with their 95% confidence intervals (CI). If RD was significant, number needed to treat (NNT) was calculated. MAIN RESULTS: Eight trials assessing the impact of inhaled corticosteroid for the prevention of CLD were identified. The study by Kovacs 1998 was excluded as investigators evaluated the impact of a combination of systemic and inhaled corticosteroid for prevention of CLD. Seven trials qualified for inclusion in this review but data from two of these studies are awaiting assessment. Thus, the present review includes data analyses based on five qualifying trials. There was no statistically significant effect of inhaled steroids on CLD either at 28 days or at 36 weeks CGA, when analyzed either for all randomized infants or amongst survivors. No statistically significant differences were noted for mortality or for the combined outcome of mortality and CLD either at 28 days of age or at 36 weeks CGA. The meta-analysis supports a reduction in the need for systemic steroids, RR 0.78 (95% CI 0.62, 0.99), RD -0. 097 (95% CI -0.187, -0.008); however statistical heterogeneity was noted. The number needed to treat (NNT) to reduce the need for systemic steroid was 10 (95% CI 5.3, 125). There were no statistically significant differences in adverse events between groups. REVIEWER'S CONCLUSIONS: There is no evidence from the trials reviewed that early administration (in the first 2 weeks of life) of inhaled steroids to ventilated preterm neonates was effective in reducing the incidence of CLD. There was a reduction in the need for systemic steroids. Although this difference was statistically significant, there was significant heterogeneity between studies and the upper limit of the 95% CI for this outcome was very close to no effect. Currently, use of inhaled steroids in this population cannot be recommended. Studies are needed to identify the risk/benefit ratio of different delivery techniques and dosing schedules for the administration of these medications. Studies need to address both the short-term and long-term benefits and adverse effects of inhaled steroids with particular attention to neurodevelopmental outcome.

Administration, Inhalation↗
PubMed1993

Effects of radon inhalation on biological function--lipid peroxide level, superoxide dismutase activity, and membrane fluidity.

We administered radon (Rn) to rabbits by inhalation and examined changes in the lipid peroxide (TBARS) level, superoxide dismutase (SOD) activity, and membrane fluidity in various organs to clarify the therapeutic effects of Rn. The lipid peroxide level of the brain was significantly decreased immediately after Rn inhalation for 90 min in both the low concentration group (about 7-10 kBq/liter) and the high concentration group (about 14-18 kBq/liter) as compared with that in the control group. It further decreased in the low concentration group but slightly recovered in the high concentration group 2 h after inhalation. The lipid peroxide level of the lung showed no change immediately after inhalation but decreased significantly in both groups 2 h after inhalation. With regard to SOD activity in the brain and lung, only that in the brain showed significant increase in the high concentration group immediately after inhalation; no other change was observed. Membrane fluidity, especially the fluidity of membrane protein, was significantly increased in the brains of both groups immediately after inhalation, and that 2 h after inhalation in the lung was significantly increased in both groups. These findings suggest that the inhalation of Rn at Rn springs contributes to the prevention of brain disorders related to peroxidation reactions by promoting these physiologic changes.

Administration, Inhalation↗
PubMed1996

Chronic inhalation toxicity and carcinogenicity testing of respirable fibrous particles. Workshop report.

On May 8-10, 1995, a workshop on chronic inhalation toxicity and carcinogenicity testing of respirable fibrous particles was held in Chapel Hill, North Carolina. The workshop was sponsored by the Office of Pollution Prevention and Toxics, U.S. Environmental Protection Agency (EPA), in collaboration with the National Institute of Environmental Health Sciences (NIEHS), the National Institute for Occupational Safety and Health (NIOSH), and the Occupational Safety and Health Administration (OSHA). The goal of the workshop was to obtain input from the scientific community on a number of issues related to fiber testing. Major issues for discussion were: (i) the optimal design and conduct of studies of the health effects of chronic inhalation exposure of animals to fibers; (ii) preliminary studies which would be useful guides in designing the chronic exposure study; (iii) mechanistic studies which would be important adjuncts to the chronic exposure study to enable better interpretation of study results and extrapolation of potential effects in exposed humans; and (iv) available screening tests which can be used to develop a minimum data set for (a) making decisions about the potential health hazard of the fibers and (b) prioritizing the need for further testing in a chronic inhalation study. After extensive discussion and debate of the workshop issues, the general consensus of the expert panel is that chronic inhalation studies of fibers in the rat are the most appropriate tests for predicting inhalation hazard and risk of fibers to humans. A number of guidances specific for the design and conduct of prechronic and chronic inhalation studies of fibers in rodents were recommended. For instance, it was recommended that along with other information (decrease in body weight, systemic toxicity, etc.), data should be obtained on lung burdens and bronchoalveolar lavage fluid analysis to assist in establishing the chronic exposure levels. Lung burden data are also important for quantifying aspects of risk assessment related to dosimetric adjustments before extrapolation. Although mechanistic studies are not recommended as part of the standard chronic inhalation studies, the expert panel stressed the need for obtaining mechanistic information as far as possible during the course of subchronic or chronic inhalation studies. At present, no single assay and battery of short-term assays can predict the outcome of a chronic inhalation bioassay with respect to carcinogenic effects. Meanwhile, several short-term in vitro and in vivo studies that may be useful to assess the relative potential of fibrous substances to cause lung toxicity/carcinogenicity have been identified.

Administration, Inhalation↗
PubMed1993

Salmeterol: an inhaled beta 2-agonist with prolonged duration of action.

Salmeterol (Serevent) is an inhaled beta 2-receptor agonist with more than twelve hours' effect duration compared with 4-6 hours for the more short-acting substances bitolterol, fenoterol, salbutamol, and terbutaline. Salmeterol has been studied in several large-scale double-blind multicenter studies with up to one year's duration. More than 6,000 asthmatics have been treated with salmeterol during these controlled studies. All studies show salmeterol to have a significantly better and well-maintained bronchodilating effect with better asthma control, fewer asthma exacerbations, and a decreased need for rescue albuterol inhalations used on demand compared to the treatments in the control groups (200-400 micrograms albuterol q.i.d., inhaled albuterol given only p.r.n., terbutaline given regularly, or individually titrated slow-release theophylline). Salmeterol should be given b.i.d. and in combination with inhaled corticosteroids. Salmeterol seems especially effective in patients with nocturnal symptoms, exercise induced asthma, and in patients sensitive to inhaled irritants such as cold air. The patients should always have short-acting inhaled beta 2-agonists available for break-through attacks. Inhaled salmeterol in combination with inhaled steroids seems to give the best maintenance asthma control available by inhalation today.

Administration, Inhalation↗