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E-cigarette or vaping product use-associated lung injury (EVALI) is a severe pulmonary illness associated with the use of e-cigarettes or vaping products that was officially identified and named in 2019. This American Thoracic Society workshop was convened in 2021 to identify and prioritize research and regulatory needs to adequately respond to the EVALI outbreak and to prevent similar instances of disease associated with e-cigarette or vaping product use. An interdisciplinary group of 26 experts in adult and pediatric clinical care, public health, regulatory oversight, and toxicology were convened for the workshop. Four major topics were examined: 1 ) the public health and regulatory response to EVALI; 2 ) EVALI clinical care; 3 ) mechanisms contributing to EVALI; and 4 ) needed actions to address the health effects of EVALI. Oral presentations and group discussion were the primary modes used to identify top priorities for addressing EVALI. Initiatives including a national EVALI case registry and biorepository, integrated electronic medical record coding system, U.S. Food and Drug Administration regulation and enforcement of nicotine e-cigarette standards, regulatory authority over nontobacco-derived e-cigarettes, training in evaluating exogenous exposures, prospective clinical studies, standardized clinical follow-up assessments, ability to more readily study effects of cannabinoid e-cigarettes, and research to identify biomarkers of exposure and disease were identified as critical needs. These initiatives will require substantial federal investment as well as changes to regulatory policy. Overall, the workshop identified the need to address the root causes of EVALI to prevent future outbreaks. An integrated approach from multiple perspectives is required, including public health; clinical, basic, and translational research; regulators; and users of e-cigarettes. Improving the public health response to reduce the risk of another substantial disease-inducing event depends on coordinated actions to better understand the inhalational toxicity of these products, informing the public of the risks, and developing and enforcing regulatory standards for all e-cigarettes.

Introduction: Recent infectious outbreaks preceding the COVID-19 crisis resulted in the evolution of vigilance for preparedness against the next pandemic. This vigilance was maintained to varying degrees in different jurisdictions., Objective: To evaluate the evolution of vigilance following previous epidemics and pandemics and the subsequent atrophy of vigilance prior to the COVID-19 global pandemic., Methods: We evaluated documentation discussing US, Canada, and South Korea from March 2002 to October 2021. Our policy search strategy was rooted in academic literature, government documents and media reports., Results: In the US, there were examples of atrophy of vigilance; however, there was clear understanding of pandemic readiness actions that were simply not executed amongst political chaos. In Canada, political mishaps were less evident at the time the pandemic unfolded. Nevertheless, atrophy was evident with erosion in preparedness programs following SARS. South Korea appeared least subjected to atrophy of vigilance. The more recent MERS outbreak prompted evolution of sustained vigilance and compliance with basic public health measures such as mask wearing., Recommendations: Policy options need to be explored and instituted that increase protection of preparedness programs through institutional safeguards and accountability measure., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Witek and Schwartz.)

Background: The United States Food and Drug Administration (FDA) monitors, inspects, and enforces the promotion of products by companies that claim to mitigate, prevent, treat, diagnose, or cure COVID-19. The introduction of COVID-19-related diagnostics and therapeutics during the pandemic has highlighted the significance of rigorous clinical trials to ensure safety and efficacy of such interventions. The objective of this report is to provide a descriptive review of promotional violations of health products for COVID-19 infection., Methods: Warning letters issued by the FDA's Center for Drug Evaluation and Research were retrieved over an 18 month period (March 6, 2020, to August 30, 2021) to identify promotional violations. FDA violation letters categorized as "Unapproved and Misbranded Products Related to Coronavirus Disease 2019 (COVID-19)" were reviewed. A content analysis was performed for each letter to identify categories for product type, promotional venue, violation type, and country of origin. For cannabidiol-related violations, a content analysis was repeated within its own product category., Results: A total of 130 letters were reported. Across all letters, cannabidiol products were the most frequent subject of violation (15/130; 11.5%). Of the cannabidiol letters, all reported the promotion of unapproved products (15/15; 100%), misbranding (15/15; 100%), and/or had claims that lacked scientific substantiation (14/15; 93.3%). All promotional violations were linked to websites (15/15; 100%), along with other mainstream venues: Facebook, Instagram, YouTube, Twitter, LinkedIn, and email. Lastly, the cannabidiol products were described to provide therapeutic benefit to COVID-19, by acting as an anti-viral (5; 33.3%), pro-inflammatory (1; 6.7%), anti-inflammatory (7; 46.7%), immune-booster (5; 40%), immune-suppressor (2; 13.3%), and/or other (2; 13.3%)., Conclusion: Despite the urgent need for COVID-19 treatments, promotional material by companies must comply with standard regulatory requirements, namely substantiation of claims. As the pandemic persists, the FDA must continue their efforts to monitor, inspect, and enforce violative companies. Cannabidiol-related substances led the spectrum of products with unsubstantiated claims to treat COVID-19 infection. Improving awareness among the public, healthcare providers, and stakeholders highlights the value of drug approval process, while protecting public safety., (© 2021. The Author(s).)

Pharmaceutical development was at the forefront of efforts to prevent infection with the SARS-CoV-2 virus as well as to treat its often-devastating effects. Drug development, and its multifaceted and multi-disciplined activity toward effective vaccines and drugs, became part of everyday news. I review several key areas of vaccine and drug development that were brought into the public mainstream over the evolution of the pandemic. These include the unprecedented speed of vaccine discovery and development, issues uncovered from early clinical studies, and regulatory concepts that were highlighted throughout the development process. Among these was the importance of pharmacovigilance as each new agent was rapidly deployed to a mostly eager public. Critical challenges around production, packaging, and procurement of product for patient use were often centre stage. Finally, the ever-important need to transition not only from scientific concept to vaccine and drug, but from their authorized and approved use to their implementation in health systems to insure the intended effects both in individuals and populations., (© 2021. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

The Emergency Use Authorization (EUA) originated in 2004 because of the need for emergency medical countermeasures (MCMs) against potential bioterrorist attacks. The EUA also proved useful in dealing with subsequent pandemics and has emerged as a critical regulatory pathway for therapeutics and vaccines throughout the Coronavirus Disease 2019 (COVID-19) pandemic. With the EUA process in the USA, we witnessed emergency authorizations, their expansions, as well as withdrawal of previously authorized products, which exemplifies the dynamic nature of scientific review of EUA products. EUAs proved vital for the first group of COVID-19 vaccines, including the temporary pause of one vaccine while emergency safety issues were evaluated. Although this review on the EUA is primarily focused on the USA, distinctions were made with other jurisdictions such as Europe and Canada with respect to the emergency authorizations of the vaccines. Finally, we discuss some important differences following EUA and formal new drug/vaccine application (NDA/BLA) approvals., (© 2021. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Importance: As global jurisdictions shift toward cannabis legalization, 2 areas of public health importance relate to exposure to youth and to truthful promotion. Although Canada's Cannabis Act specifies many prohibitions related to cannabis promotion, no systematic monitoring or enforcement among licensed firms exists. Compliance with marketing regulations has effects beyond Canadian citizens because of the global outreach of websites and social media., Objectives: To evaluate compliance among licensed firms with the Cannabis Act and analyze trends among violations regarding promotional material., Design, Setting, and Participants: This cross-sectional study evaluated cannabis-licensed firms after cannabis legalization. Data were extracted from online public platforms, including company websites, Facebook, Instagram, and Twitter, from October 1, 2019, to March 31, 2020. Descriptive statistics, Poisson regression, and logistic regression were used to analyze the associations of covariates with promotion violations., Main Outcomes and Measures: The primary outcome was characterization of type and prevalence of promotion violations. Secondary outcomes were the role of various covariates (namely, licensed firm characteristics and online platforms) in the frequency and probability of violations. Hypotheses were formulated before data collection., Results: Among 261 licensed firms, 211 (80.8%) had an online platform, including 204 (96.7%) with websites, 128 (60.7%) with Facebook, 123 (58.3%) with Instagram, and 123 (58.3%) with Twitter. Of all licensed firms with an online platform, 182 (86.3%) had at least 1 violation. Compared with websites, the risk of violations was significantly higher on Facebook (rate ratio [RR], 1.24; 95% CI, 1.11-1.39) and Instagram (RR, 1.19; 95% CI, 1.05-1.34). The most common violations included lack of age restrictions, brand glamorization, and omission of risk information. With websites as the reference group, lack of age restrictions was approximately 15 times more likely to occur on Facebook (odds ratio [OR], 14.76; 95% CI, 8.06-27.05); the odds of an age restriction violation were also higher on Instagram (OR, 2.48; 95% CI, 1.43-4.32) and Twitter (OR, 4.03; 95% CI, 2.29-7.09). For unsubstantiated claims, the odds of violations were significantly decreased on Facebook (OR, 0.23; 95% CI, 0.11-0.48) and Instagram (OR, 0.28; 95% CI, 0.14-0.57). The odds of glamorization were associated with an increase on Instagram (OR, 2.90; 95% CI, 1.72-4.88)., Conclusions and Relevance: In this cross-sectional study, widespread violations were observed in online Canadian cannabis promotion. To protect public health and safety amid legalization, decision-makers should make explicit federal regulation and enforcement regarding promotional activities of cannabis retailers. These results suggest that policy and enforcement of cannabis promotion in Canada would have an international impact, from ease of access to online media and downstream consequences of unregulated promotion.

The drug development process of demonstrating an agent is safe, effective and pure has, with rare exception, proven an exemplary path in translational research. The basic science, the clinical trials and the chemistry, manufacturing and control have served public health well. This carefully regulated approach forms the basis of a drug label with data from these studies also used to convey risk and benefit to prescribing physicians through the channels of medical literature and drug promotion by the industry. The latter is also important to public health in that such promotion must be based in the approved indication, be truthful, not be misleading and be substantiated by sufficient evidence. Why then is the emergence of "medical marijuana" any different? While substantial evidence exists for some conditions and some related products have undergone careful investigation through to NDA approval, most claims are not substantiated by research but driven by misguided enthusiasm. While recreational use of marijuana is not at debate here, nor is the right of an individual patient to explore cannabis therapeutically; however, allowing broad unsubstantiated claims around medicinal cannabis to infiltrate the general public is a disservice. To distill the potential medical benefits through the pharmacologic understanding of the endocannabinoid system, cannabis should follow the traditional drug development process or one that improves upon it. Until then, claims should remain as stated hypothesis to accept or reject.

Introduction: In the United States, all pharmaceutical promotional activities must comply with regulatory standards set by the Food and Drug Administration (FDA); failure to comply may lead to receiving an FDA enforcement letter. Letters include details of the specific advertisement in violation, as well as the action that is required by the company to rectify the non-compliant promotion., Objectives: The aim of this study was to determine trends in enforcement letters from the FDA to parties responsible for pharmaceutical promotion violations from 2005 to 2019., Methods: A longitudinal trend analysis was conducted of FDA enforcement letters sent to pharmaceutical companies from 2005 to 2019 (n = 318). Publicly available enforcement letters released by the Office of Prescription Drug Promotion were accessed and analysed online through the Center for Drug Evaluation and Research, a part of the FDA. Variables analysed included number of letters by year, violation categories, venues, intended audience, drug age and company revenues. Publicly available revenue was the major source for company revenue information., Results: The total number of enforcement letters significantly decreased over time. Violations concerning risk information were significantly more prevalent than all other violation categories. Online promotional materials were most frequently cited. Proportionally, larger companies received the majority of letters in earlier years of observation, and smaller companies in later years (2013-2019)., Conclusions: These trends are of value for industry and regulators alike in refining policy to ensure fair, balanced and meaningful information in pharmaceutical promotion. The frequency of violation letters has decreased in recent years; however, smaller companies have increasingly received the majority of letters. Small firms must increase their compliance around informing drug risk potential with balanced safety information across all promotional venues. Specifically, these findings are useful for pharmaceutical companies to direct educational efforts to promotional staff and their advertising agencies, especially regarding online advertising.

The Baseline (BDI) and Transition (TDI) Dyspnea Indexes provide interview-based measurements of breathlessness related to activities of daily living. The BDI is a discriminative instrument that includes specific criteria for each of three components at a single point in time. The TDI is an evaluative instrument that includes specific criteria for each of three components to measure changes from a baseline state. Observational studies have shown that patients with COPD generally experience a gradual progression of breathing difficulty as measured by the TDI over time. Randomized controlled trials have demonstrated excellent measurement characteristics of the TDI; these include responsiveness (ability to detect change) and construct validity (a change in the TDI correlates with changes in other variables). Supporting evidence for one unit as the minimal clinically important difference (MCID) of the TDI is based on: expert preference; use of the physician's global evaluation score as an anchor; and distribution estimates (standard error of measurement and 0.5 of the standard deviation). As an alternative to the interview process, self-administered computerized (SAC) versions of the BDI/TDI have been developed to provide direct patient-reported ratings of dyspnea. To further establish the MCID of the interview-administered and/or the SAC TDI, we recommend that a patient's report of global ratings of change by used as an independent standard or anchor.

Study Objectives: Pulmonary rehabilitation (PR) improves exercise tolerance in COPD patients. Tiotropium is a once-daily, inhaled anticholinergic bronchodilator that provides sustained 24-h improvements in airflow and lung hyperinflation reduction. We hypothesized that ventilatory mechanics improvements from tiotropium would permit enhanced ability to train muscles of ambulation and therefore augment exercise tolerance benefits of PR., Design: In a randomized, double-blind, placebo-controlled trial (tiotropium, n = 47; placebo, n = 44), tiotropium (18 microg qd) was administered to COPD patients participating in 8 weeks of PR (treadmill training three times a week; >/= 30 min per session) at 17 sites. Study drug was administered 5 weeks prior to, 8 weeks during, and 12 weeks following PR. The primary end point was treadmill walking (0% incline) endurance time at 80% of maximum speed attained in an initial incremental test. The transition dyspnea index (TDI), St. George's respiratory questionnaire (SGRQ), and rescue albuterol use were secondary end points., Participants: Mean age of the 93 participants was 67 years, 57% were men, and mean FEV(1) was 0.88 L (34% predicted)., Results: Mean endurance time differences (tiotropium minus placebo) prior to PR, at the end of PR, and 12 weeks after PR were 1.65 min (p = 0.183), 5.35 min (p = 0.025), and 6.60 min (p = 0.018), respectively. Mean TDI focal scores at the end of PR were 1.75 for tiotropium and 0.91 for placebo (p > 0.05). At 12 weeks after PR, TDI focal scores were 1.75 for tiotropium and 0.08 for placebo (p < 0.05). Relative to placebo, tiotropium improved SGRQ total scores by 3.86 at the end of PR and 4.44 at 12 weeks after PR (p > 0.05). Mean albuterol use declined following PR plus tiotropium, compared to PR alone (p

Ths object of this study was to examine validity, meaningful effect sizes, and patterns of response of the Transition Dyspnea Index (TDI) in a clinical trial cohort of chronic obstructive pulmonary disease (COPD) patients. The design was a retrospective analysis of data from a randomized, double-blind placebo-controlled clinical trial. We analyzed fifty clinical investigation sites in United States. There were 921 patients with stable COPD. Tiotropium 18 microg dry powder or matching placebo was used. Patients were allowed to remain on usual care less ipratropium bromide. Construct validity was demonstrated by significant correlations (P <.05) between Baseline Dyspnea Index (BDI) and other baseline measures, as well as between TDI and changes in other measures at the end of 1 year. Concurrent validity was observed by the significant correlation between TDI and dyspnea diary responses. Changes in TDI focal score were in the range of one unit when the group was stratified by a minimal change in the physician's global evaluation. Significantly less (P <.05) supplemental albuterol was observed in the group of responders defined by a one-unit improvement in TDI. Responders also had few exacerbations and better health status. The validity of the TDI is supported in a large clinical trial setting. A one-unit change in the TDI focal score represented the minimal important difference.

Dyspnoea is a primary symptom of chronic obstructive pulmonary disease (COPD). The baseline (BDI) and transition (TDI) dyspnoea indices are commonly used instruments to assess breathlessness and the impact of intervention. Its validity and pattern of response in multinational clinical trials has not been established. In a retrospective analysis of a cohort of 997 COPD patients who received tiotropium, salmeterol or placebo, in addition to usual care, the validity and pattern of response of the BDI and TDI were examined. The BDI was significantly correlated with the dyspnoea diary (DD) score and the symptom and activity components of the St. George's respiratory questionnaire (SGRQ), establishing concurrent validity. Furthermore, the TDI was also correlated with the changes in DD, SGRQ symptom and activity scores. Construct validity was established by the association between baseline forced expiratory volume in one second (FEV1) and BDI and AFEVI with TDI. Physician's global evaluation (PGE) was significantly associated with BDI as well as APGE with TDI. Significant correlations have also been observed when the cohorts were classified according to native English and native non-English speaking countries. A change in PGE of 1 category (i.e. 2 units on an 8-point scale) was associated with a mean TDI of approximately 1 unit (0.9-1.3 mean focal score), lending further support to the clinical significance of this change inherent in the instrument's descriptors. TDI responders (i.e. focal score < or = 1 unit) used less supplemental salbutamol, had fewer exacerbations and had significantly improved health status as measured by impacts and total SGRQ scores compared with nonresponders. In conclusion, the transition dyspnoea index is a valid instrument when used in a multinational clinical trial and the patterns of response confirm a 1-unit change in the transition dyspnoea index focal score as being clinically important.

Background: Tiotropium, a once-daily anticholinergic, and salmeterol represent two inhaled, long-acting bronchodilators from different pharmacologic classes. A trial was designed to examine the efficacy and safety of both compounds with multiple outcome measures, including lung function, dyspnea, and health-related quality of life (HRQoL) in patients with COPD., Methods: A 6-month, randomized, placebo-controlled, double-blind, double-dummy, parallel-group study of tiotropium, 18 microg once daily via dry-powder inhaler, compared with salmeterol, 50 microg bid via metered-dose inhaler, was conducted in patients with COPD. Efficacy was assessed by 12-h monitoring of spirometry, transition dyspnea index (TDI), and the St. George's Respiratory Questionnaire (SGRQ)., Results: A total of 623 patients participated (tiotropium, n= 209; salmeterol, n = 213; and placebo, n = 201). The groups were similar in age (mean, 65 years), gender (75% men), and baseline FEV(1) (mean, 1.08 +/- 0.37 L; percent predicted, 40 +/- 12% [+/- SD]). Compared with placebo treatment, the mean predose morning FEV(1) following 6 months of therapy increased significantly more for the tiotropium group (0.14 L) than the salmeterol group (0.09 L; p < 0.01). The average FEV(1) (0 to 12 h) for tiotropium was statistically superior to salmeterol (difference, 0.08 L; p < 0.001). Tiotropium improved TDI focal score by 1.02 U compared with placebo (p = 0.01), whereas there was no significant change in TDI focal score with salmeterol (0.24 U). Tiotropium was superior to salmeterol in improving TDI focal score (p < 0.05). At 6 months, the mean improvement in SGRQ total score vs baseline was tiotropium, - 5.14 U (p < 0.05 vs placebo); salmeterol, - 3.54 U (p = 0.4 vs placebo); and placebo, - 2.43 U. A statistically higher proportion of patients receiving tiotropium achieved at least a 4-U change in SGRQ score compared to patients receiving placebo. Both active drugs reduced the need for rescue albuterol (p < 0.0001)., Conclusions: Tiotropium once daily produces superior bronchodilation, improvements in dyspnea, and proportion of patients achieving meaningful changes in HRQoL compared to twice-daily salmeterol in patients with COPD.

Study Objective: To compare the efficacy and safety of ipratropium bromide reformulated with the chlorofluorocarbon (CFC)-free propellant hydrofluoroalkane (HFA)-134a (ipratropium bromide HFA) to that of the marketed ipratropium bromide inhalation aerosol (containing CFC) in patients with COPD., Design: This was a randomized, double-blind, parallel-group, placebo-controlled, multicenter trial. The primary efficacy parameter was acute bronchodilator response. The primary end points were peak change in FEV(1) from baseline and area under the response-time curve., Setting: Thirty-one clinical centers in the United States participated in this project., Patients: A total of 507 patients with moderate-to-severe COPD were randomized, and 444 patients completed the trial., Interventions: Twelve weeks of treatment four times daily with one of the following: ipratropium bromide HFA, 42 microg; ipratropium bromide HFA, 84 microg; HFA placebo; ipratropium bromide inhalation aerosol, 42 microg; or CFC placebo., Measurements and Results: Patients in all active treatment groups had significant bronchodilator responses as shown by increases in mean FEV(1) from baseline of at least 15%. Bronchodilator response in all active treatment groups was also significantly more than their respective placebo treatments based on FEV(1), area under the time-response curve from 0 to 6 h, and peak response. FVC results were similar to those seen with FEV(1). There were no significant differences in adverse events, laboratory findings, or ECG findings among the treatment groups., Conclusions: Ipratropium bromide HFA, 42 and mgr;g, provided bronchodilation comparable to the marketed ipratropium bromide CFC, 42 and mgr;g, over 12 weeks of regular use.

The HandiHaler is a dry powder breath activated inhaler system developed for inhalation therapy for patients with airway disease. Its operation is based on the evacuation of powder from a pierced capsule. We sought to document the inspiratory flow rates attained by patients inspiring through the HandiHaler with various degrees of airflow limitation. Subjects with stable chronic obstructive pulmonary disease (COPD) were the study's population. An in vitro study of fine particle dose was conducted using an Andersen Cascade Impactor to assess medication delivery at low inspiratory flow rates. Subsequently, an in vivo study was conducted to determine inspiratory flow rates in patients with COPD as measured through a pneumotach with a custom coupler device with and without the HandiHaler. Patients were classified into three approximately equal groups of spirometric severity ranging from mild (46-65% predicted normal forced expiratory volume in 1 sec [FEV1]), to moderate (28-45%) to severe (< or = 27%). The in vitro study indicated delivery of medication at flow rates as low as 20 L/min. Twenty-six men completed the in vivo study (age 66.9 +/- 10.9 years, FEV1 = 1.02 +/- 0.45 l.). The median peak inspiratory flow rates attained in the mild (n = 8), moderate (n = 10), and severe (n = 8) categories were 45, 45.6, and 35.4 L/min respectively. The minimum peak inspiratory flow rates in the three groups were 28.2, 21.6 and 20.4 L/min. The HandiHaler device effectively delivers particles to the lung over a wide range of airflow limitation in patients with COPD.

Study Objective: To compare the bronchodilator efficacy and safety of tiotropium and placebo., Design: A 3-month, randomized, double-blind, placebo-controlled, multicenter trial., Setting: Outpatient., Patients: Four hundred seventy patients with stable COPD (mean FEV(1) = 38.6% predicted)., Interventions: Tiotropium 18 microg (N = 279) or placebo (N = 191) given once daily via a lactose-based dry-powder inhaler device., Measurements and Results: Spirometry was evaluated on days 1, 8, 50, and 92. Data were expressed as the mean trough (ie, before morning dose; 23 to 24 h after previous dose) and average response observed in the 3 h after the dose was received. Tiotropium produced significant improvement in trough FEV(1) and FVC, averaging 12% greater than baseline on day 8; these improvements were maintained on days 50 and 92. The average postdose FEV(1) was 16% greater than baseline on day 1 and 20% greater than baseline on day 92; FVC was 17% greater than baseline on day 1 and 19% greater than baseline on day 92. Tiotropium was significantly more effective than placebo in both trough and average FEV(1) and FVC response (p < 0.001). These spirometric effects were corroborated by significant improvements in daily morning and evening peak expiratory flow rate, as well as a reduction in "as-needed" albuterol use. Symptoms of wheezing and shortness of breath were significantly less in patients receiving tiotropium, and the physician global assessment noted overall improvements with those treated with tiotropium relative to placebo. The most common reported adverse event after tiotropium was dry mouth (9.3% vs 1.6% relative to placebo; p < 0.05)., Conclusions: These data demonstrate that tiotropium is a safe and effective once-daily anticholinergic bronchodilator and should prove useful as first-line maintenance therapy in COPD.

Prior to a drug achieving its effects (ie, pharmacodynamics), there are numerous events within the body that determine its ultimate fate. The effects of the "body on the drug" has been referred to as pharmacokinetics-how the favorable lung-to-systemic effects predicted from this exercise translate into practice. Inhaled drugs have enjoyed the major feature of having "local" effects on the target organ of the lung. Broadly, lower doses can be used and adverse effects are often less than with oral or parenteral administration. Nevertheless, key features of respiratory drugs and their administration can impact their fate and ultimate utility. This review has provided some relevant examples of basic pharmacokinetics principles as related to inhaled products, with emphasis on those factors that help to partition lung-to-systemic effects.

Tiotropium (Spiriva; Ba679BR) is a new-generation, long-acting anticholinergic bronchodilator that has muscarinic M(1) and M(3) receptor subtype selectivity. A multicenter, randomized, double-blind, parallel group, placebo-controlled study was conducted to evaluate the dose-response characteristics of tiotropium inhalation powder given once daily to stable patients with chronic obstructive pulmonary disease (COPD). Patients (mean FEV(1) = 1.08 L [42% predicted]) were randomized to receive 0, 4.5, 9, 18, or 36 microg tiotropium once daily at noon for 4 wk, with spirometry done before and hourly for 6 h after dosing. Patients measured and recorded their peak expiratory flow rates (PEFRs) three times each day. Significant dose-related improvement in FEV(1) and significant improvement in FVC occurred within 1 h after the first dose of tiotropium as compared with placebo. Over the 29 d of the study, all doses of tiotropium produced significant increases over placebo in trough (i.e., as measured spirometrically at 20 to 24 h after the previous dose and just before the next dose of tiotropium), peak, and 6-h postdose average FEV(1) and FVC, and in PEFR, without a significant difference among the different doses investigated. PEFR gradually returned to pretreatment baseline levels over a 3-wk evaluation period following the discontinuation of tiotropium. The overall safety profile for the tiotropium doses was similar to that for placebo. In summary, tiotropium was shown to be safe and effective in doses ranging from 4.5 to 36 microg delivered once daily. The improvements in spirometry with once-daily dosing confirm the long duration of action of tiotropium reported in single-dose studies, and its sustained improvement of spirometric measures over the 1 mo of testing in the study points to utility of tiotropium as a maintenance bronchodilator for patients with COPD. On the basis of the comparable bronchodilator response at doses from 9 to 36 microg, and advantages suggested by the safety profile at doses below 36 microg in this study, a dose of 18 microg once daily was selected for use in long-term studies of the safety and efficacy of tiotropium.

Antimuscarinic treatment of airway disease has a long and colorful history leading to its present day use as an effective bronchodilator in chronic obstructed pulmonary disease (COPD) as well as an antisecretory drug for watery rhinorrhea. Present formulations are limited to ipratropium bromide, a safe and effective respiratory therapeutic. The bronchodilation from ipratropium, as documented by spirometry, has been well established both alone and in combination with albuterol. Evidence suggests that anticholinergics can affect other important aspects of COPD, such as dynamic hyperinflation, and further studies are warranted to confirm long-term physiologic effects and associated health outcomes. Finally, current development of the long-acting compound tiotropium has provided hope for the next generation of antimuscarinic agents represented by once-daily therapy.

Study Objectives: To determine whether the combination of ipratropium bromide and albuterol results in greater and more consistent pulmonary function test (PFT) response rates than ipratropium bromide or albuterol alone in patients with COPD., Design: Retrospective review of two recently completed 3-month, randomized, double-blind, parallel, multicenter, phase III trials., Setting: Outpatient., Patients: A total of 1,067 stable patients with COPD., Interventions: Ipratropium bromide (36 microg qid), albuterol base (180 microg qid), or an equivalent combination of ipratropium bromide and albuterol sulfate (42 microg and 240 microg qid, respectively)., Measurements and Results: PFT response rates were analyzed using 12% and 15% increases in FEV1 compared with baseline values and were measured in the various treatment groups on days 1, 29, 57, and 85 in these trials. Regardless of whether a 12% or a 15% increase in FEV1 was used to define a positive response, an equivalent combination of ipratropium bromide and albuterol sulfate was superior to the individual agents (p < 0.05; all comparisons within 30 min). In addition, a 15% or more increase in FEV1 was seen in > 80% of patients who received the combination of ipratropium and albuterol sulfate during the initial PFT and continued to be observed 3 months after initial testing., Conclusions: Use of a combination of ipratropium bromide and albuterol sulfate is superior to the individual agents in identifying PFT reversibility in patients with COPD.

Study Objective: To conduct a post hoc pharmacoeconomic evaluation of two double-blind, randomized, prospective, parallel group studies comparing the long-term efficacy and safety of ipratropium combined with albuterol in a single inhalational canister against either bronchodilator agent alone in patients with COPD., Patients: One thousand sixty-seven patients with COPD., Methods: The dose of each bronchodilator was two puffs four times a day (42 microg of ipratropium bromide, 240 microg of albuterol sulfate). Pulmonary function testing was performed on days 1, 29, 57, and 85 of treatment. Outcomes, health-care resource consumption, and costs were compared for the three treatment groups over the 85-day study period. A total of 1,067 patients were randomized in the two studies (albuterol alone, n = 347; ipratropium alone, n = 362; albuterol plus ipratropium, n = 358)., Results: Improvement in FEV1 and area under the FEV1 response-time curve from time 0 to 4 h (FEV1AUC0-4) was significantly greater for the combination of albuterol plus ipratropium than either agent alone on all test days. Compared with albuterol, patients receiving ipratropium and ipratropium plus albuterol experienced significantly fewer COPD exacerbations and patient-days of exacerbation. In addition, the increased frequency of exacerbations observed in the albuterol group was associated with a significant increase in the number of patient hospital days and antibiotic and corticosteroid use. As a result, the total cost of treatment over the study period was significantly less for ipratropium ($156 per patient) and ipratropium plus albuterol ($197 per patient) than for albuterol ($269 per patient). Increased cost-effectiveness, defined as total estimated treatment cost per mean change in FEV1AUC0-4, was observed in both treatment arms containing ipratropium., Conclusions: The inclusion of ipratropium in a pharmacologic treatment regimen is associated with a lower rate of exacerbations in COPD. The result is lower total treatment costs and improved cost-effectiveness.

Inhaled antimuscarinics, often called anticholinergics in clinical medicine, are established as first line bronchodilators in COPD. Tiotropium has been developed as a new generation antimuscarinic following ipratropium. Tiotropium is a specific, highly potent antimuscarinic, demonstrating very slow dissociation from muscarinic receptors. Dissociation from M2-receptors is faster than from M3 or M1, which in functional in vitro studies, appeared as kinetic receptor subtype selectivity of M3 and M1 over M2. The high potency and slow receptor dissociation found its clinical correlate in significant and long lasting bronchodilatation and bronchoprotection in patients with COPD and asthma. In asthma, protection against methacholine challenge exceeded the study period of 48 hours. In COPD, bronchodilatation of about 80% of the plateau was demonstrated after the first dose. Following chronic once daily inhalation for 28 days, the improvement in pulmonary function was sustained and there was a further increase in peak effects, but more importantly a rising baseline, achieving steady state within 2 weeks. Tiotropium achieves very stable long lasting effects with comparatively low variation of bronchodilatation between peak and trough (the level before the next administration). Stable 24 hour effectiveness profiles the compound as the first once daily bronchodilator. Clinical correlates of kinetic receptor subtype selective blockade remain to be shown. Plasma levels of tiotropium at trough are in the low pg/ml range and are unlikely to explain the sustained effectiveness in the airways. Slow dissociation from muscarinic receptors is likely to be responsible for the long duration of action.

Human rhinovirus (HRV) accounts for a significant portion of common-cold illness, with the peak incidence being in the early fall. Three hundred forty-six adults who had self-diagnosed colds of 48 h or less were enrolled in a study during September and October 1994 to determine the frequency and clinical course of HRV infections. Nasal wash specimens for viral culture and reverse transcription-PCR (RT-PCR) for HRV RNA and human coronavirus OC43 and 229E RNA detection were collected on enrollment, and participants recorded their symptoms twice daily for 14 days. Middle ear pressure (MEP) was measured with a digital tympanometer on days 1 and 7. Picornaviruses (224 HRV and 7 enterovirus isolates) were detected by culture in 67% (231 of 346) of the subjects. Among 114 samples negative by culture, HRV was detected by RT-PCR in 52 (46%) for an overall picornavirus infection rate of 82% (283 of 346 subjects). Among the remaining 62 negative samples, human coronavirus RNA was detected by RT-PCR in 5 patients, so that 288 (83%) of patients had documented viral infection. The first symptom noticed most often was sore throat (40%) in HRV culture- or PCR-positive patients and stuffy nose in HRV-negative patients (27%). No differences in symptom scores over time or in the presence of individual symptoms were noted between groups. The median duration of the cold episodes was 11 days in HRV culture-positive patients, 9.5 days in HRV RT-PCR-positive patients, and 11.5 days in HRV-negative patients. On enrollment, abnormal MEPs (< or = -100 or > or = +100 mm of H2O) were found for 21% of HRV culture-positive patients, 14% of HRV RT-PCR-positive patients, and 10% of HRV-negative patients. No important differences in the clinical course of HRV culture-positive, HRV culture-negative and RT-PCR-positive, or HRV-negative colds were found. These results represent the highest frequency of virologically confirmed natural colds to date and document the importance of rhinoviruses as the cause of colds during fall months.

Background: While first generation H1-receptor antagonists are widely used, there are relatively few data describing their comparative effects on subjective daytime sleepiness and psychomotor performance., Objective: To compare the effects of first generation H1 receptor antagonists on subjective daytime sleepiness and psychomotor performance., Methods: We conducted two single-dose, cross-over studies. In the first, we validated our methodology in 18 healthy subjects by examining the response to diphenhydramine (50 mg), terfenadine (60 mg), and placebo. In the second trial, we evaluated the relative effects following diphenhydramine (50 mg), diphenhydramine (25 mg), chlorpheniramine (4 mg), and placebo. Psychomotor tests included choice reaction time, hand steadiness, and a test that divided attention between tracking and reaction time. Introspective drowsiness was measured using a visual analog scale and the Stanford Sleepiness Scale. Assessments were made prior to dosing and at one, three, and five hours after dosing; a 7-hour post-drug assessment was included in the second trial., Results: In the first trial, 50 mg diphenhydramine produced significant impairment relative to placebo in both subjective and objective assessments (P < .05). Responses following terfenadine did not differ from placebo. In the second study, all three regimens produced subjective and objective soporific effects to a significantly greater degree than placebo. For example, significant introspective sleepiness was noted three hours following all three regimens (P < .05) and slower choice reaction times were noted one and three hours after dosing (P < .05). The general rank order of effects was diphenhydramine (50 mg), followed by diphenhydramine (25 mg), followed by chlorpheniramine (4 mg). Significant differences among the three regimens were, for the most part, confined to greater soporific effects from diphenhydramine relative to chlorpheniramine (P < .05)., Conclusions: Taken together, our observations confirm that subjective and objective measures of sleepiness and psychomotor performance occur following single doses of diphenhydramine and chlorpheniramine, but not terfenadine. Differences in soporific effects do exist among regimens of first-generation compounds.

Partial expiratory flow-volume (PEFV) curves are a useful tool in airway challenge studies, but unlike the maximal expiratory flow-volume (MEFV) curve, lung function parameters require manual calculation from the flow-volume tracing. We describe an algorithm written in QuickBASIC that analyzes a PEFV curve superimposed on a MEFV curve by (1) identifying the PEFV curve, (2) locating the maximal expiratory flow at the point on the PEFV curve that corresponds to 60% of the baseline forced vital capacity (FVC) below total lung capacity (TLC), termed MEF40%(P), and (3) identifying the size of the PEFV curve along the TLC axis. A report of these parameters is also provided. This algorithm was validated using flow-volume curves from a clinical study in which eight subjects performed two sets of MEFV and PEFV curves separated by approximately 1 hr. Paired comparison of MEF40%(P) determined by the algorithm and two independent manual calculations correlated strongly and yielded no statistically significant differences between the two methods. We conclude that this algorithm provides rapid and accurate determinations of PEFV parameters.

Exposure to aerosols of organic dusts such as coffee, tea, spices, soy, fur, and animal food in an occupational setting can affect the respiratory health of industrial workers. Based on our experience with workers from many small industries processing organic materials, we discuss the clinical features and possible mechanisms responsible for the respiratory impairment associated with these types of dust exposure. Significantly higher prevalences for most chronic respiratory symptoms were found among exposed workers than among control workers. Smoking appears to aggravate these symptoms. A large number of exposed workers complained of acute symptoms which developed during the work shift. In exposed workers, significant across-shift reductions in lung function were recorded for all spirometric tests, but particularly for the flow rates at 50% and 25% of vital capacity on maximum expiratory flow-volume curves. Comparison of preshift measured ventilatory capacity tests with predicted normal values indicates that these workers demonstrate obstructive changes affecting primarily flow rate at low lung volumes. The data suggest that exposure to organic aerosols in industrial settings, particularly in conjunction with smoking, may be associated with the development of chronic obstructive lung disease.

Phenindamine, an H1-receptor antagonist that was developed almost 50 years ago, has been associated with both drowsiness and insomnia. Since its central nervous system profile has not been well characterized, we used a series of psychomotor tests to conduct two studies. In the first, 12 subjects received single oral doses of phenindamine (25 mg), diphenhydramine (50 mg), terfenadine (60 mg), or placebo in a four-way crossover study. Psychomotor tests included choice reaction time (CRT), tracking, and hand steadiness (HS). In the second trial, 15 subjects received single oral doses of phenindamine (25 mg), pseudoephedrine (60 mg), phenindamine and pseudoephedrine, diphenhydramine (50 mg), or placebo in a five-way crossover study. Psychomotor tests included CRT, HS, and a task that divided attention between tracking and reaction time. Introspective drowsiness was measured in both trials with use of a visual analog scale (VAS) and the Stanford Sleepiness Scale (SSS). All assessments were made before and 1, 3, and 5 hours after drug administration. In the first trial, diphenhydramine produced significant impairment relative to placebo (p < 0.05) in CRT, tracking, and HS tasks and higher SSS and VAS scores, with peak effect noted at 3 hours. Phenindamine did not significantly differ from placebo or terfenadine. In the second trial, diphenhydramine produced significant impairment relative to placebo (p < 0.05) in CRT, divided attention, HS, and VAS, and SSS, also peaking at 3 hours. Stanford Sleepiness Scale scores after phenindamine were greater than placebo at 3 hours (p < 0.05) but significantly less than diphenhydramine (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

The effects of CAAD (diphenhydramine hydrochloride, 50 mg; pseudoephedrine hydrochloride, 60 mg; acetaminophen, 1 g in 10% ethanol) were evaluated in a double-blind, three-way, placebo-controlled, cross-over study on 18 volunteers with allergic rhinitis. The number of sneezes following nasal challenge with antigen was significantly reduced after a bed-time dose of CAAD (P less than .005) and a single dose of diphenhydramine (P less than .001) given 2 hours before the challenge. The levels of N-alpha-tosyl-L-arginine methyl ester (TAME) activity decreased after diphenhydramine treatment, while histamine levels following challenge were not different. The drowsiness reported after CAAD was equal to placebo, but significantly less than diphenhydramine (P less than .002 for both). The active treatments reduced the actions of histamine without suppressing its release from mast cells. The effect of CAAD persists 10 hours after administration without inducing drowsiness.

The objective of this study was to evaluate the effect of 60 micrograms oxymetazoline on nasal mucosal blood flow (NMBF) measured by laser Doppler velocimetry. Nasal airflow (measured by anterior rhinomanometry) and subjectively perceived airflow (measured by visual analog scales) were also evaluated. A reduction of NMBF (mL/100 g tissue/min) was observed following local application of 60 micrograms oxymetazoline that was not observed after the vehicle was applied. For example, NMBF at baseline was measured at 78.8 +/- 10.3 mL/100 g tissue/min (mean +/- SEM). During the five minutes following vehicle application, mean values remained at 81.8 +/- 8.8 mL/100 g tissue/min. Five minutes after topical oxymetazoline treatment, NMBF was reduced 49% to 38.3 +/- 10.2 mL/100 g tissue/min. Nasal airflow (mL/sec), which was measured before and after LDV probe placement, was not significantly increased in either the ipsilateral (281.4 +/- 33.1 to 314.3 +/- 31.6) or contralateral nostril (335.7 +/- 26.9 to 262.1 +/- 36.4), probably due to the limited surface application of drug. Subjective assessments of congestion by both the investigator and the subject showed significant improvements in the ipsilateral nostril. We conclude that, under the conditions of our study, localized application of 60 micrograms oxymetazoline significantly reduces superficial nasal blood flow and provides subjectively perceived improvements in nasal stuffiness.

The lung function response to inhalation of an extract of green coffee was studied in ten healthy subjects who were prescreened for airway hyperresponsiveness to an aerosol of green coffee extract. The effects of this provocation were evaluated at rest and following moderate exercise as well as with and without pretreatment with 80 mg of disodium cromoglycate (DSCG). There was a statistically significant decrement in lung function over time (P less than .001) following coffee provocation both at rest and following exercise. No significant protection against this response was observed with DSCG pretreatment. While the majority of these "healthy" coffee reactors exhibited baseline nonspecific airway hyperresponsiveness to methacholine (PC20 FEV1 less than 25 mg/mL in 7/10), there was no correlation in these ten subjects between baseline responsiveness to methacholine and the degree of lung function decrement following coffee (P greater than .05). Also, no correlation was observed between skin prick and lung function response to coffee extract. We conclude that inhalation of green coffee extract causes significant bronchoconstriction in selected healthy volunteers and that this response is not prevented by pretreatment with DSCG.

A follow-up study of respiratory function in cotton textile workers was performed 10 yr after the original cross-sectional study (1975 to 1985). There were 35 nonsmoking female and 31 smoking male textile workers restudied from the original group of 116. The majority of those lost to follow-up had left the industry. The prevalence of byssinosis among the female workers at the time of follow-up was 15/35 (42.9%) compared with 8/35 (22.9%) at the time of the initial study (p = 0.063). For men the byssinosis prevalence at follow-up was 16/31 (51.6%) compared with 8/31 (22.9%) at the time of the initial study (p = 0.03). Similarly, the prevalence of almost all other respiratory symptoms was significantly higher at the follow-up than at the time of the initial study. Significant across-shift decrements in FEV1 and FVC were documented at both surveys. The mean annual decline in ventilatory capacity was greater than expected for both female (FVC: -0.036 +/- 0.005 L/yr; FEV1: -0.059 +/- 0.009 L/yr) and male workers (FVC: -0.059 +/- 0.008 L/yr; FEV1: -0.068 +/- 0.006 L/yr) (Mean +/- SE). The mean total airborne dust concentration measured at the time of the follow-up study was 3.95 mg/m3 with an average respirable dust concentration of 0.97 mg/m3. We conclude that continued exposure to high dust concentrations in the cotton textile industry is associated with an increasing prevalence of respiratory symptoms and progressive impairment of lung function. The increase in respiratory impairment was seen both in smokers and nonsmokers.

Immunological and respiratory findings were studied in a group of 19 male soybean workers. Twenty control workers also participated in the immunological studies. All soybean workers had positive immediate skin reactions to soybean extract, as did 19/20 control workers. Similarly, 18/19 soy workers reacted to soy antigen prepared after separation from oil, but only 3/19 to soy lecithin antigen and 1 to soy oil antigen. A majority of soy workers (13/19) reacted to house dust. Only 3/19 soy workers had increased levels of soy-specific IgE. The prevalence of chronic respiratory symptoms was higher in exposed than in control workers, being significantly different for dyspnea (P less than 0.01). Workers with increased specific serum IgE or positive skin tests to house dust did not have any more symptoms than workers with negative tests. Ventilatory function was significantly worse in soybean workers than expected. Nevertheless, workers with positive skin or serological tests to house dust had across-shift changes similar to those with negative tests. These data suggest that skin and airway responses to soybean components (particularly the non-lipid ones) are very frequent among soybean workers. In the current study specific (soy) and non-specific (house dust) skin tests and immunoglobulins did not allow us to identify the workers at risk of developing symptoms or lung function abnormalities. This suggests that in addition to any atopic mechanisms, the irritant effect of soy dust may play a role in this occupational airway disease.

Respiratory symptoms and abnormalities of lung function were studied in 84 female and 27 male hemp workers employed in two textile mills (A and B) processing soft hemp (C sativa). In mill A 46 women and 27 men were investigated and 38 female workers were studied in mill B. Forty nine women and 30 men from a non-dusty industry served as controls. A significantly higher prevalence of almost all chronic respiratory symptoms was found in female hemp workers when compared to control workers. Among the men these differences were significant for nasal catarrh and sinusitis. A high prevalence of byssinosis was found among female hemp workers in both mills (group A, 47.8%; group B, 57.9%) as well as in the male workers (66.7%). Statistically significant across shift reductions in lung function were found for all ventilatory capacity measurements in female and male hemp workers varying from 7.1% for forced expiratory volume in one second (FEV1) to 15.1% for flow rates at 50% vital capacity (FEF50). Measured Monday baseline values before the work shift were significantly lower than expected for hemp workers, being particularly reduced for FEF25 and FEF50. The data suggest that occupational exposure to hemp dust is a significant risk factor for the development of acute and chronic lung disease in workers employed in this textile industry.

It has been suggested that exposure to formaldehyde (FA) induces asthmatic symptomatology. We have previously studied healthy and asthmatic individuals and found that lung function was unaltered by controlled exposures to 2.0 ppm FA with and without mild exercise. Our present study extends these observations to a group of hospital laboratory workers routinely exposed to FA. Fifteen laboratory workers were exposed in double-blind, random sequence to 0 and 2 ppm FA for 40 min in an environmental chamber with temperature and relative humidity held constant at 23 degrees C and 50%, respectively. These exposures were repeated on two more occasions with a 10-min exercise regimen (450 kpm/min) after being in the chamber 5 min. In addition, a symptom diary and measurements of peak expiratory flow rate (PEFR) were recorded for 24 hr after exposure. Lung function remained unaltered for all 4 exposure days; e.g., mean FEV1.0 for the group did not change by more than 3% at any testing time on any exposure day. Also, there were no delayed obstructive changes as measured by PEFR recordings. Symptoms were mild and transient with unusual odor and eye irritation the most frequent complaint. No lower airway symptoms were reported. We conclude that this group of healthy laboratory workers did not experience any acute or delayed lung function changes from exposure to 2.0 ppm FA at rest and with exercise and that irritative symptoms were few.

Several bronchodilator drugs commonly used in respiratory therapy contain sodium metabisulfite as an antioxidant preservative. When aerosolized, these agents may release the irritant gas SO2 as a result of bisulfite decomposition. We found that agents that contain bisulfites generated SO2 concentrations of 2.0 ppm and greater, while bronchodilator solutions without bisulfite did not. Such levels are known to induce or to exacerbate asthmatic symptoms. Levels of SO2 were higher when solutions were nebulized with compressed air from a tank or electric compressor than when they were nebulized from a hand-bulb nebulizer. No significant lot-to-lot variations were found in the solutions tested.

Air pollution is frequently incriminated as a risk factor in the development of chronic lung impairment and in the aggravation of existing disease. The federal government has set primary air quality standards to protect public health and secondary standards to protect public welfare (eg, to preserve vegetation and buildings). Much of the debate surrounding the development and evaluation of air standards focuses on the diseases of patients with whom the respiratory care practitioner has daily contact. We review the legislative efforts to protect the public from the effects of air pollution and provide insight into some of the scientific and medical dilemmas involved in this current public health issue.

Fifteen asthmatic volunteers were exposed in a double-blind, random manner to room air and 2.0 ppm formaldehyde for 40 min in an environmental chamber. These exposures were repeated on a separate day during moderate exercise (450 kpm/min) for 10 min. Ambient and dew point temperatures were 23.0 +/- 0.0 degrees C and 11.5 +/- 1.0 degrees C, respectively. No significant airway obstruction as measured by flow-volume parameters and airway resistance was noted in this group during or immediately after exposure. Furthermore, sequential measurements of peak flow for 24 hr following formaldehyde exposure revealed no delayed airway response. In contrast, in comparison to the baseline methacholine inhalation challenge (MIC) test on the screening day, 8 of 12 asthmatics demonstrated a lower threshold to MIC following 2.0 ppm exposure for 40 min; however, the mean and median decrements of threshold in methacholine concentration of 10.4 mg/ml and 24.3 mg/ml were not significant (p = .12). Bad odor, sore throat, and eye irritation were common during exposure but symptoms were infrequent afterward.

Sulfur dioxide (SO2) is a common air pollutant found in the workplace. Considerable variation exists in the airway responses of asthmatics to the inhalation of SO2. To determine if such variation among asthmatics is related to nonspecific airway reactivity, we compared the threshold doses of methacholine and SO2 required to produce significant changes in flow rates at 60% of the vital capacity below total lung capacity on the partial expiratory flow volume curve in a group of eight mildly asthmatic subjects. A significant correlation between the dose of SO2 and the dose of methacholine required to produce bronchoconstriction (r = .86, p less than .05) was observed, suggesting that there is a relationship between the response to SO2 and the response to methacholine in mildly asthmatic individuals. More generally, nonspecific airway hyperreactivity may help to predict untoward airway responses to inhaled SO2 in the workplace.

Airway challenge with cotton bract extract (CBE) causes reversible bronchospasm in most volunteers never before exposed to CBE or the textile industry. Lung function abnormalities develop slowly after inhalation with a maximum effect reached within 2 hours and lung function slowly improving thereafter. When CBE was injected intradermally in three naive subjects with negligible airway response to CBE, we observed an initial wheal-and-flare reaction within minutes followed by erythema and subsequent induration that persisted for 24 to 48 hours. Microscopic examination of skin biopsy specimens obtained during the course of these reactions revealed edema in the early phase followed by perivascular infiltration of a mixed cellular nature in the subsequent stages of the reaction. Degranulation of mast cells was noted throughout the course of the reaction. These findings indirectly suggest that a nonspecific inflammatory reaction initiated by mast cell-derived mediators and sustained by the presence of infiltrating cells may be responsible for some of the airway effects observed in byssinosis.

This study examined nonspecific airway responsiveness to methacholine (MC) after inhalation of cotton bract extract (CBE). In a randomized double-blind, crossover trial, 13 healthy volunteers underwent an MC inhalation challenge test prior to inhalation of CBE and normal saline solution (NSS) aerosol sham as well as 2, 8, 24, and 168 h (7 days) later. The response parameter was the concentration of MC required to induce a 25% decrement in the maximal expiratory flow at 40% of the vital capacity below total lung capacity on the partial expiratory flow-volume curve (PC25MEF40%(P]. Five of 13 subjects demonstrated a ventilatory response to CBE with a 20% or larger decrement in the MEF40%(P); no subject demonstrated such change with NSS. For the group, the maximal decrement in MEF40%(P) was to 76.5 +/- 20.3% of baseline (mean +/- SD), occurring approximately 60 to 90 min after provocation, whereas the largest decrement after normal saline was to 88 +/- 10.6% of baseline, occurring immediately after inhalation. Changes in airway responsiveness to MC were transient. For example, the PC25MEF40%(P) for the group (mean +/- SD) was 51.3 +/- 41.1 mg/ml at baseline and 25.8 +/- 30.3 and 52.2 +/- 57.3 mg/ml at 2 and 8 h. After a pre-sham baseline of 50.4 +/- 43.2 mg/ml, PC25MEF40%(P) was 57.6 +/- 83.8 and 153.8 +/- 148 mg/ml at 2 and 8 h. Repeated measures ANOVA on these acute, same-day changes (i.e., 2 and 8 h after provocation) demonstrated a statistically significant effect of CBE on airway responsiveness (p = 0.048). These data demonstrate that inhalation of CBE, in addition to bronchospasm, causes a transient increase in airway responsiveness.

The acute effect of herbal tea dust extracts on lung function was studied in 15 of 25 healthy subjects responding to the inhalation of these extracts. Bronchial inhalation challenge was performed with tea extracts (sage, dog rose and gruzyan) and with normal saline solution as a control substance to assess their baseline airway reactivity to an isotonic aerosol. Lung function testing was performed before exposure and at 0, 15, 30, and 60 minutes after the cessation of exposure. The same subjects were also tested by challenge with methacholine. Lung function was measured by recording FVC, FEV1, FEF50, FEF25, SGaw, and Raw. Subjects were skin tested by the skin prick method and serum IgE levels were determined. The findings suggested that neither baseline nonspecific airway reactivity nor specific markers of immediate sensitivity to tea predict airway responses to tea extracts. Further evaluation of immunologic markers may help to explain the onset and progression of airway disease in workers.

A maximal lung inflation is known to alter airway tone in man. Recent investigations, examining how this phenomenon relates to bronchial provocation testing, suggest that a deep inspiration will decrease airway resistance and underestimate the subsequent decrement in lung function following airway challenge. Because the recovery of baseline tone is rapid following a deep inspiration, we evaluated the consistency of three consecutive partial and maximal expiratory flow-volume maneuvers performed at approximately 45- to 60-second intervals. Functional parameters including the forced expiratory volume in 1 s and the maximal expiratory flow at 60% of the vital capacity below total lung capacity on the partial curve (MEF40%P) were constant at each measurement point following induced bronchoconstriction or bronchodilation in both healthy and asthmatic subjects. We suggest that with 45 s between maneuvers, repeatable parameters can be attained from three consecutive flow-volume curves.

Unlabelled: We conducted a prospective study of 50 consecutive postoperative patients over a 5-month period to characterize the bacterial contamination of ultrasonic nebulizers (USNs) after 24, 48, and 72 hours (h) of use., Methods: Samples of the USN effluent mist and reservoir fluid were cultured and the results were correlated with clinical data from patient records, especially indications of pneumonia or related infections., Results: Two thirds of the USNs were bacteria-free at the three times they were tested. After 24 h, cultures of the mist revealed bacterial growth in only 1 of the 50 patients. After 48 and 72 h, cultures of the mist showed bacterial growth in 6 instances (12%). Colonization of the reservoir fluid was also limited to 1 patient after 24 h. Reservoir-fluid cultures were positive in 10% of the USNs at 48 h and in 18% at 72 h. No clinically significant signs of pneumonia developed in any patient., Conclusions: These results suggest that colonization of USNs is minimal during the first 72 h of use by postoperative patients with uncomplicated clinical courses and that clinical consequences are unlikely in such patients even when the USN is found to have been colonized. Although the Centers for Disease Control has recommended daily changing of USN circuits, this practice may not be warranted in all clinical settings. Further studies are needed to determine the colonization of USNs used by patients with more complicated clinical courses.

It is well established that cotton dust inhalation can compromise lung function in textile workers. Challenges with a water-soluble extract of cotton bract (CBE) can also induce reversible airway obstruction in healthy volunteers. We have examined the effect of inhaled CBE in nonhuman primates and have attempted to inhibit the bronchoconstrictive response with mediator modifying compounds. CBE (34 mg/ml or 100 mg/ml) was administered via IPPB for 15 minutes (15 breaths/min) in 12 intubated, anesthetized, adult male monkeys (Macaca fascicularis). Breath-by-breath determinations of pulmonary resistance, dynamic compliance (Cdyn), tidal volume, and breathing frequency were calculated from the transpulmonary pressure (esophageal balloon) and airflow signals and monitored for 2 hr postchallenge. Control challenges with distilled water were also performed in 3 monkeys with the greatest response from CBE. Five animals (42%) were found to respond to CBE with peak % changes in Cdyn greater than 45%. In 3 of these animals, we attempted to blunt the CBE response with chlorpheniramine (0.1 mg/kg i.v.) and a mast cell stabilizer lodoxamide (0.1 mg/ml aerosol). In these 3 animals the mean (+/- SD) peak % changes in Cdyn to CBE alone was -47.4 +/- 1.8. The CBE response following chlorpheneramine was -49 +/- 15.7 and following lodoxamide was -47.0 +/- 5.4. These data suggest that monkeys, like humans, can develop reproducible bronchoconstriction following an aerosol challenge with CBE. Furthermore, this bronchoconstriction in the monkey is probably not explained by the action of histamine or mediator release alone and an acute inflammatory reaction may be involved.

Formaldehyde (FA) is a common indoor air pollutant with irritative properties. It has been suggested that FA may produce physiologic alterations of the respiratory system. To study such responses, 15 nonsmoking, healthy subjects were exposed in a double blind, random manner to 0 and 2 ppm FA for 40 min in an environmental chamber. In addition, the same exposures were repeated on a separate day with the subjects performing moderate exercise (450 kpm/min) for 10 min. Exposures were carried out under controlled environmental conditions (temperature = 23 degrees C, relative humidity = 50%). Pulmonary function was measured before, during, and after exposures using partial and maximal flow-volume curves and airway resistance. Symptom diaries were given to the subjects; upper and lower airway symptoms were recorded for up to 24 hr following exposures. No significant bronchoconstriction was noted in this group. In 3 subjects, sequential measurements of peak flow over a 24-hr period following FA exposure failed to reveal any delayed airway response. On a separate day, 6 healthy subjects failed to demonstrate changes from their baseline responsiveness to methacholine after exposure to 2 ppm FA. Respiratory symptoms were, in general, confined to the upper airways and were mild to moderate in severity. We conclude that short exposures to 2 ppm FA do not result in acute or subacute changes in lung function among healthy individuals either at rest or with exercise. Subjective complaints following such exposures are confined to irritative phenomena of the upper airways.