Systematic review of the effects of patient errors using inhaled delivery systems on clinical outcomes in COPD.

BACKGROUND: Errors using inhaled delivery systems for COPD are common and it is assumed that these lead to worse clinical outcomes. Previous systematic reviews have included patients with both asthma and COPD and much of the evidence related to asthma. More studies in COPD have now been published. Through systematic review, the relationship between errors using inhalers and clinical outcomes in COPD, including the importance of specific errors, was assessed.MethodsElectronic databases were searched on 27 October 2023 to identify cohort, case-control or randomised controlled studies, which included patients with COPD, an objective assessment of inhaler errors and data on at least one outcome of interest (forced expiratory volume in 1 s, (FEV1), dyspnoea, health status and exacerbations). Study quality was assessed using the Newcastle and Ottawa scales. A narrative synthesis of the results was performed as there was insufficient detail in the publications to allow quantitative synthesis. There was no funding for the review. RESULTS: 19 publications were included (7 cohort and 12 case-control) reporting outcomes on 6487 patients. 15 were considered low quality, and most were confounded by the absence of adherence data. There was weak evidence that lower error rates are associated with better FEV1, symptoms and health status and fewer exacerbations. Only one considered the effects of individual errors and found that only some were related to worse outcomes. CONCLUSION: Evidence about the importance of specific errors using inhalers and outcomes would optimise the education and training of patients with COPD. Prospective studies, including objective monitoring of inhalation technique and adherence, are needed. PROSPERO REGISTRATION NUMBER: CRD42023393120.

Clinical Burden of Chronic Obstructive Pulmonary Disease in Patients with Suboptimal Peak Inspiratory Flow.

Introduction: Many patients with chronic obstructive pulmonary disease (COPD) may derive inadequate benefit from dry powder inhalers (DPIs) because of suboptimal peak inspiratory flow (sPIF). Objectives: To assess the clinical burden of COPD by characterizing the clinical characteristics of participants with sPIF against medium-low resistance DPIs versus those with optimal PIF (oPIF) from two phase 3 clinical trials. Methods: Baseline data were collected from two randomized, controlled, phase 3 trials (NCT03095456; NCT02518139) in participants with moderate-to-severe COPD. oPIF (60 L/min) against the medium-low resistance DPIs was used as the threshold for defining the PIF subgroups (<60 L/min (sPIF) vs ≥60 L/min (oPIF)). Results: Most participants included in this analysis were White (92%) and male (63%); the mean (range) age was 65 (43-87) years. Participants with sPIF had significantly greater dyspnea than those with oPIF as measured using the modified Medical Research Council scoring (mean (95% CI): 2.1 (2.0-2.2) vs 1.6 (1.4-1.7); P < 0.001) and baseline dyspnea index (mean (95% CI): 5.1 (4.9-5.4) vs 6.1 (5.8-6.3); P < 0.001). Based on COPD Assessment Test scores, participants with sPIF had a higher COPD symptom burden than those with oPIF (mean (95% CI): 21.5 (19.7-23.3) vs 19.5 (18.6-20.4); P = 0.05). Conclusion: In these trials, participants with COPD who had sPIF against the medium-low resistance DPIs had more dyspnea and worse health status than those with oPIF. These results demonstrate that sPIF is associated with a higher clinical burden as measured by patient-reported outcomes.

Guidance on Mitigating the Risk of Transmitting Respiratory Infections During Nebulization by the COPD Foundation Nebulizer Consortium.

BACKGROUND: Nebulizers are used commonly for inhaled drug delivery. Because they deliver medication through aerosol generation, clarification is needed on what constitutes safe aerosol delivery in infectious respiratory disease settings. The COVID-19 pandemic highlighted the importance of understanding the safety and potential risks of aerosol-generating procedures. However, evidence supporting the increased risk of disease transmission with nebulized treatments is inconclusive, and inconsistent guidelines and differing opinions have left uncertainty regarding their use. Many clinicians opt for alternative devices, but this practice could impact outcomes negatively, especially for patients who may not derive full treatment benefit from handheld inhalers. Therefore, it is prudent to develop strategies that can be used during nebulized treatment to minimize the emission of fugitive aerosols, these comprising bioaerosols exhaled by infected individuals and medical aerosols generated by the device that also may be contaminated. This is particularly relevant for patient care in the context of a highly transmissible virus. RESEARCH QUESTION: How can potential risks of infections during nebulization be mitigated? STUDY DESIGN AND METHODS: The COPD Foundation Nebulizer Consortium (CNC) was formed in 2020 to address uncertainties surrounding administration of nebulized medication. The CNC is an international, multidisciplinary collaboration of patient advocates, pulmonary physicians, critical care physicians, respiratory therapists, clinical scientists, and pharmacists from research centers, medical centers, professional societies, industry, and government agencies. The CNC developed this expert guidance to inform the safe use of nebulized therapies for patients and providers and to answer key questions surrounding medication delivery with nebulizers during pandemics or when exposure to common respiratory pathogens is anticipated. RESULTS: CNC members reviewed literature and guidelines regarding nebulization and developed two sets of guidance statements: one for the health care setting and one for the home environment. INTERPRETATION: Future studies need to explore the risk of disease transmission with fugitive aerosols associated with different nebulizer types in real patient care situations and to evaluate the effectiveness of mitigation strategies.

Consideration and Assessment of Patient Factors When Selecting an Inhaled Delivery System in COPD.

Because guidelines and strategies for pharmacologic treatment of COPD focus on specific classes of inhaled medications, there is an unmet need for information to guide health care professionals for selecting an inhaled medication delivery system that matches the unique characteristics of individual patients. This article provides guidance for selecting an inhaled medication delivery system based on three "key" patient factors: cognitive function, manual dexterity/strength, and peak inspiratory flow. In addition, information is provided about specific tests to assess these patient factors. Cognitive impairment with an estimated prevalence of 25% among patients with COPD adversely affects patients' ability to correctly use a handheld device. To our knowledge, the prevalence of impaired manual dexterity/strength has not been reported in those with COPD. However, 79% of patients with COPD have reported one or more physical impediments that could influence their ability to manipulate an inhaler device. The measurement of peak inspiratory flow against the simulated resistance (PIFr) of a dry powder inhaler establishes whether the patient has the inhalation ability for creating optimal turbulent energy within the device. A suboptimal PIFr for low to medium-high resistance dry powder inhalers has been reported in 19% to 84% of stable outpatients with COPD. Health care professionals should consider cognitive function, manual dexterity/strength, and PIFr in their patients with COPD when prescribing inhaled pharmacotherapy. Impairments in these patient factors are common among those with COPD and can affect the individual's competency and effectiveness of using inhaled medications delivered by handheld devices.

Clinical Implications of Peak Inspiratory Flow in COPD: Post Hoc Analyses of the TRONARTO Study.

Background: In patients with COPD, inhalation ability should be assessed when considering inhaler choice. To evaluate whether the soft mist inhaler (SMI) is suitable for COPD patients irrespective of inhalation ability, the TRONARTO study investigated the efficacy of dual long-acting bronchodilator therapy delivered via the Respimat® SMI on lung function in patients with COPD stratified by inhalation ability. Tiotropium/olodaterol delivered via the SMI was effective both in patients with peak inspiratory flow (PIF) <60 L/min and PIF ≥60 L/min, measured against medium-low resistance. Methods: This congress compilation summarizes post hoc analyses from the TRONARTO study presented at the annual American Thoracic Society 2022 and European Respiratory Society 2022 meetings. These analyses evaluated PIF in over 200 patients, with PIF measurements taken daily at home for 4 weeks, and in the clinic at baseline, Weeks 2 and 4. Results: Overall, 57.9% of patients had a PIF range (difference between lowest and highest PIF measurements) <20 L/min (12.4% of patients had PIF range <10 L/min). At-home PIF range decreased over the study period, suggesting that inhaler training/repeated PIF measurements may help to make patients' inspiratory effort more consistent. Some patient characteristics correlated with lower PIF (female gender, shorter stature, more severe disease, worse airflow obstruction) and lower PIF range (more severe disease). PIF measurements differed between medium-low and high-resistance settings, highlighting the importance of measuring PIF at the resistance of a patient's inhaler. PIF correlated poorly with spirometry measurements. Conclusion: As indicated in COPD management guidelines, choice of inhaler is essential to optimize pharmacologic therapies for COPD. Poor inspiratory ability should be viewed as a treatable trait that can help to inform inhaler choice. Inhaler training and consideration of PIF (if patients use a dry powder inhaler) can reduce patient-to-inhaler mismatch, with potential consequences for health status and exacerbation risk.

Personalizing Selection of Inhaled Delivery Systems in Chronic Obstructive Pulmonary Disease.

It can be challenging for healthcare professionals (HCPs) to prescribe inhaled therapy for patients with chronic obstructive pulmonary disease (COPD) because of the multiple individual and combinations of inhaled medications available in numerous delivery systems. Guidance on the selection of an inhaled delivery system has received limited attention compared with the emphasis on prescribing the class of the inhaled molecule(s). Although numerous recommendations and algorithms have been proposed to guide the selection of an inhaled delivery system for patients with COPD, no specific approach has been endorsed in COPD guidelines/strategies or by professional organizations. To provide recommendations for an inhaler selection strategy at initial and follow-up appointments, we examined the impact of patient errors using handheld inhalers on clinical outcomes and performed a focused narrative review to consider patient factors (continuity of the inhaled delivery system, cognitive function, manual function/dexterity, and peak inspiratory flow) when selecting an inhaled delivery system. On the basis of these findings, five questions are proposed for HCPs to consider in the initial selection of an inhaler delivery system and three questions to consider at follow-up. We propose that HCPs consider the inhaled medication delivery system as a unit and to match appropriate medication(s) with the unique features of the delivery system to individual patient factors. Assessment of inhaler technique and adherence together with patient outcomes/satisfaction at each visit is essential to determine whether the inhaled medication delivery system is providing benefits. Continued and repeated education on device features and correct technique is warranted to optimize efficacy.

Reducing the Risk of Mortality in Chronic Obstructive Pulmonary Disease With Pharmacotherapy: A Narrative Review.

In 2020, chronic obstructive pulmonary disease (COPD) was the fifth leading cause of death in the United States excluding COVID-19, and its mortality burden has been rising since the 1980s. Smoking cessation, long-term oxygen therapy, noninvasive ventilation, and lung volume reduction surgery have had a beneficial effect on mortality; however, until recently, the effects of pharmacologic therapies on all-cause mortality have been unclear. Inhaled pharmacologic treatments for patients with COPD include combinations of long-acting muscarinic receptor antagonists (LAMAs), long-acting-ß2-agonists (LABAs), and inhaled corticosteroids (ICS). The recent IMPACT and ETHOS clinical trials reported mortality benefits with ICS/LAMA/LABA triple therapy compared with LAMA/LABA dual therapy. In IMPACT, fluticasone furoate/umeclidinium/vilanterol therapy significantly reduced the risk of on-/off-treatment all-cause mortality vs umeclidinium/vilanterol (hazard ratio, 0.72; 95% CI, 0.53 to 0.99; P=.042). The ETHOS trial found a reduction in the risk of on-/off-treatment all-cause mortality in patients treated with budesonide/glycopyrrolate/formoterol vs glycopyrrolate/formoterol (hazard ratio, 0.51 [0.33 to 0.80]; nominal P=.0035). Both trials included populations of patients with symptomatic COPD at high risk of future exacerbations, and a post hoc analysis of the final retrieved vital status data suggested that the observed mortality benefits are conferred by the ICS component. In conclusion, triple therapy reduces the risk of mortality in patients with symptomatic COPD characterized by moderate or severe airflow obstruction and a recent history of moderate or severe exacerbations. This benefit is likely to be driven by reductions in exacerbations. Future research efforts should focus on improving the long-term prognosis of patients living with COPD.

Effect of dexamethasone on dyspnoea in patients with cancer (ABCD): a parallel-group, double-blind, randomised, controlled trial.

BACKGROUND: Systemic corticosteroids are commonly prescribed for palliation of dyspnoea in patients with cancer, despite scarce evidence to support their use. We aimed to assess the effect of high-dose dexamethasone versus placebo on cancer-related dyspnoea. METHODS: The parallel-group, double-blind, randomised, controlled ABCD (Alleviating Breathlessness in Cancer Patients with Dexamethasone) trial was done at the at the University of Texas MD Anderson Cancer Center and the general oncology clinic at Lyndon B Johnson General Hospital (both in Houston, TX, USA). Ambulatory patients with cancer, aged 18 years or older, and with an average dyspnoea intensity score on an 11-point numerical rating scale (NRS; 0=none, 10=worst) over the past week of 4 or higher were randomly assigned (2:1) to receive dexamethasone 8 mg orally every 12 h for 7 days followed by 4 mg orally every 12 h for 7 days, or matching placebo capsules for 14 days. Pharmacists did permuted block randomisation with a block size of six, and patients were stratified by baseline dyspnoea score (4-6 vs 7-10) and study site. Patients, research staff, and clinicians were masked to group assignment. The primary outcome was change in dyspnoea NRS intensity over the past 24 h from baseline to day 7 (±2 days). Analyses were done by modified intention-to-treat (ie, including all patients who were randomly assigned and started the study treatment, regardless of whether they completed the study). Enrolment was stopped after the second preplanned interim analysis, when the futility criterion was met. This study is registered with ClinicalTrials.gov (NCT03367156) and is now completed. FINDINGS: Between Jan 11, 2018, and April 23, 2021, we screened 2867 patients, enrolled 149 patients, and randomly assigned 128 to dexamethasone (n=85) or placebo (n=43). The mean change in dyspnoea NRS intensity from baseline to day 7 (±2 days) was -1·6 (95% CI -2·0 to -1·2) in the dexamethasone group and -1·6 (-2·3 to -0·9) in the placebo group, with no significant between-group difference (mean 0 [95% CI -0·8 to 0·7]; p=0·48). The most common all-cause grade 3-4 adverse events were infections (nine [11%] of 85 patients in the dexamethasone group vs three [7%] of 43 in the placebo group), insomnia (seven [8%] vs one [2%]), and neuropsychiatric symptoms (three [4%] vs none [0%]). Serious adverse events, all resulting in hospital admissions, were reported in 24 (28%) of 85 patients in the dexamethasone group and in three (7%) of 43 patients in the placebo group. No treatment-related deaths occurred in either group. INTERPRETATION: High-dose dexamethasone did not improve dyspnoea in patients with cancer more effectively than placebo and was associated with a higher frequency of adverse events. These data suggest that dexamethasone should not be routinely given to unselected patients with cancer for palliation of dyspnoea. FUNDING: US National Cancer Institute.

High Prevalence of Suboptimal Peak Inspiratory Flow in Hospitalized Patients With COPD: A Real-world Study.

For optimal drug delivery, dry powder inhalers (DPIs) depend on the patient's peak inspiratory flow (PIF) and the internal resistance of the device to create turbulent energy and disaggregate the powder. A suboptimal PIF may lead to ineffective drug inhalation into the lungs. Our objective was to report the prevalence of suboptimal PIF in patients with COPD hospitalized for any reason using 1 or more DPIs. In this real-world, observational, single­site, retrospective study, PIF was measured for each DPI using the In-Check™ DIAL set to match the resistance of the DPI used by each patient. PIFs <60 and <30L/min were considered suboptimal for low to medium-high- and high-resistance DPIs, respectively. At initial hospitalization, the prevalence of suboptimal PIF was 44.6% in 829 patients (mean age, 71.7 years; 56.8% female); 21.2% were measured during admission for a COPD exacerbation. Suboptimal PIF percentages were 61.0% (38.1±9.5L/min [mean±standard deviation (SD)]) across low to medium-high-resistance DPIs and 17.2% (20.7±4.2L/min) for high-resistance DPIs. Overall, 190/829 patients had 1 or more 30-day all-cause readmission with 253 corresponding PIF measurements. For readmissions, suboptimal PIFs were observed in 49.5% (94/190) of patients. Suboptimal PIF percentages were 65.4% (38.4±9.2L/min) for low to medium-high-resistance DPIs and 19.8% (22.4±3.3L/min) for high-resistance DPIs. As the overall prevalence of suboptimal PIFs in hospitalized patients with COPD varied according to the specific internal resistance of the DPI, these findings may have clinical implications for inhaler selection.

Prospective Evaluation of Exacerbations Associated with Suboptimal Peak Inspiratory Flow Among Stable Outpatients with COPD.

Purpose: A suboptimal peak inspiratory flow (PIF) against a dry powder inhaler (DPI) may result in ineffective inhalation of medications, which may affect outcomes. The primary objective of this study was to examine the association between PIF status and COPD exacerbations among outpatients with moderate to very severe COPD. Patients and Methods: This was a prospective, observational study of patients from 7 US outpatient centers. PIF was measured using an inspiratory flow meter (In-Check™ DIAL G16) set to medium low resistance. Patients were classified by suboptimal (<60 L/min) or optimal PIF (≥60 L/min). The primary outcome was the proportion of patients with moderate/severe COPD exacerbations collected by medical record review over 12 months. Secondary outcomes were time to first exacerbation and mortality. Results: Of 474 patients screened, 38.8% had suboptimal PIF, and 71 patients with optimal PIF were excluded from the study. The enrolled sample included 184 and 219 patients with suboptimal and optimal PIF, respectively. Suboptimal PIF was associated with shorter stature (66.6±4.1 vs 67.8±3.8 inches, P = 0.002), female sex (45.1 vs 34.7%, P = 0.033), Black race (27.2 vs 11.0%, P < 0.001), and greater symptom burden (CAT: 22.3±7.7 vs 19.0±7.0, P < 0.001; mMRC: 2.0±1.1 vs 1.7±1.1, P = 0.003). The proportion of patients with COPD exacerbations at 12 months was not significantly different (29.3 vs 27.9%, P = 0.751). Suboptimal PIF was associated with shorter time to first COPD exacerbation (3.8±2.7 vs 4.9±3.0 months, P = 0.048). The mortality rate at 12 months was higher in the suboptimal cohort but not significantly different (6.5 vs 2.8%, P = 0.073). Conclusion: Over one-third of outpatients with stable moderate to very severe COPD had a suboptimal PIF against a medium low resistance DPI. The phenotype of suboptimal PIF was short stature, female, and Black. Suboptimal PIF status was associated with shorter time to moderate/severe COPD exacerbations compared with optimal PIF.

Measuring Peak Inspiratory Flow in Patients with Chronic Obstructive Pulmonary Disease.

Dry powder inhalers (DPIs) are breath actuated, and patients using DPIs need to generate an optimal inspiratory flow during the inhalation maneuver for effective drug delivery to the lungs. However, practical and standardized recommendations for measuring peak inspiratory flow (PIF)-a potential indicator for effective DPI use in chronic obstructive pulmonary disease (COPD)-are lacking. To evaluate recommended PIF assessment approaches, we reviewed the Instructions for Use of the In-Check™ DIAL and the prescribing information for eight DPIs approved for use in the treatment of COPD in the United States. To evaluate applied PIF assessment approaches, we conducted a PubMed search from inception to August 31, 2021, for reports of clinical and real-life studies where PIF was measured using the In-Check™ DIAL or through a DPI in patients with COPD. Evaluation of collective sources, including 47 applicable studies, showed that instructions related to the positioning of the patient with their DPI, instructions for exhalation before the inhalation maneuver, the inhalation maneuver itself, and post-inhalation breath-hold times varied, and in many instances, appeared vague and/or incomplete. We observed considerable variation in how PIF was measured in clinical and real-life studies, underscoring the need for a standardized method of PIF measurement. Standardization of technique will facilitate comparisons among studies. Based on these findings and our clinical and research experience, we propose specific recommendations for PIF measurement to standardize the process and better ensure accurate and reliable PIF values in clinical trials and in daily clinical practice.

A Systematic Review of Published Algorithms for Selecting an Inhaled Delivery System in Chronic Obstructive Pulmonary Disease.

Rationale: Medication for treatment of chronic obstructive pulmonary disease (COPD) is available in many different delivery systems; however, national and international guidelines do not provide recommendations on how to select the optimal system for an individual patient. Objectives: To perform a systematic review of published algorithms for inhaler selection in outpatients with COPD. Methods: PubMed, EMBASE, PsycINFO, Cochrane, and Google Scholar were searched for articles on inhaler selection published between January 1, 1990, and March 10, 2021. The results were reviewed for articles containing an algorithm for inhaler selection. The quality of publications containing an algorithm was assessed using the Joanna Briggs Institute's System for the Unified Management, Assessment and Review of Information text and opinion critical appraisal checklist. Individual steps recommended in the algorithms and the order in which they were considered were extracted independently by the two authors using the Joanna Briggs Institute's text and opinion data extraction tool. Textual syntheses and a table of factors included were used to appraise and compare algorithms. Results: The search identified 1,016 publications. After removing duplicate studies (n = 409), 607 abstracts were examined. Nine different algorithms or hierarchical recommendations for device selection were identified. All nine publications were considered of good quality. Most algorithms contain only a few decision steps. There were significant differences between the algorithms. None of the algorithms have been validated. Three domains for factors included in the algorithms were identified: patient factors, device attributes, and healthcare professional (HCP) factors. Patient factors were considered most frequently (19 times) compared with device attributes (10 times) and HCP factors (7 times). Five specific attributes/factors with at least three rankings in different algorithms were identified as key factors for device selection: ability to perform the required inspiratory maneuver and handle device correctly, sufficient inspiratory flow for dry powder inhalers, availability of molecule(s) in the device, and continuity of device. Conclusions: Although the algorithms generally provide step-by-step approaches based on a literature review and/or the experiences of the different authors, none were developed using item generation/reduction methodology or included input from patients with COPD. However, the review identified key factors that should be considered by HCPs when selecting therapy. Registration: PROSPERO (CRD42021244475).

TRONARTO: A Randomized, Placebo-Controlled Study of Tiotropium/Olodaterol Delivered via Soft Mist Inhaler in COPD Patients Stratified by Peak Inspiratory Flow.

BACKGROUND: Inhaled bronchodilator therapy is currently the mainstay of treatment for patients with chronic obstructive pulmonary disease (COPD). Some inhalers require patients to achieve certain inhalation efforts either to activate the device or to deliver medication to the site of action. For dry powder inhalers, low peak inspiratory flow (PIF) can result in poor medication delivery but the clinical significance of this is not well understood. METHODS: TRONARTO was a 4-week, randomized, double-blind, placebo-controlled, multicenter, parallel-group study which stratified patients with moderate-to-severe COPD according to their PIF against medium-low resistance at screening. Patients were randomized to receive tiotropium/olodaterol (5 µg/5 µg) or matched placebo delivered via the Respimat® Soft Mist™ inhaler (SMI). After 4 weeks of treatment, we assessed change from baseline in forced expiratory volume in 1 second (FEV1) area under the curve 0-3 hours (FEV1 AUC0-3h) and trough FEV1. RESULTS: Overall, 213 patients were randomized, of whom 106 received tiotropium/olodaterol (PIF <60 L/min, 55; PIF ≥60 L/min, 51) and 107 received placebo (PIF <60 L/min, 55; PIF ≥60 L/min, 52). For FEV1 AUC0-3h, the adjusted mean change from baseline versus placebo was 336 mL (95% confidence interval [CI] 246-425 mL; P<0.0001) in the PIF <60 L/min group and 321 mL (95% CI 233-409 mL; P<0.0001) in the PIF ≥60 L/min group. For trough FEV1, the adjusted mean change from baseline versus placebo was 201 mL (95% CI 117-286 mL; P<0.0001) in the PIF <60 L/min group and 217 mL (95% CI 135-299 mL; P<0.0001) in the PIF ≥60 L/min group. CONCLUSION: In the TRONARTO study, which included patients with moderate-to-severe COPD and varying inspiratory flow abilities, treatment with tiotropium/olodaterol resulted in significant lung function improvements versus placebo. This SMI can be used irrespective of the PIF that a patient can generate.

Peak Inspiratory Flow as a Predictive Therapeutic Biomarker in COPD.

Biomarkers in COPD may be clinical (prior exacerbation history), physiologic (FEV1), or blood based (eosinophil count or fibrinogen level). Recent interest in using biomarkers to predict response to therapy in clinical practice has emerged. The benefits of inhaled therapy depend on the correct use of the inhaler, including an appropriate inspiratory flow. Of the available delivery systems, dry powder inhalers are unique because they have an internal resistance, are breath actuated, and are flow dependent. Ideally, the user inhales "forcefully" to generate turbulent energy (determined by an individual's inspiratory flow and the resistance of the device) within the device that disaggregates the powder so that the individual inhales the medication particles into the lower respiratory tract. Because of specific features of dry powder inhalers and the required optimal inspiratory flow, an unmet need exists to identify individuals who are likely or unlikely to benefit from dry powder medications. Peak inspiratory flow, defined as the maximum airflow generated during inhalation against the simulated resistance of a dry powder inhaler, is a physiologic measure that has biological plausibility, has good test characteristics (repeatability and reliability), and is generalizable. Current evidence supports peak inspiratory flow as a predictive therapeutic biomarker to optimize therapy in both outpatients with COPD as well as those hospitalized for an exacerbation before discharge. This approach is consistent with the precepts of precision medicine, which considers differences in a person's biological features, exposure, and lifestyle to prevent and treat disease.

High-Flow Nasal Cannula Therapy for Exertional Dyspnea in Patients with Cancer: A Pilot Randomized Clinical Trial.

BACKGROUND: Exertional dyspnea is common in patients with cancer and limits their function. The impact of high-flow nasal cannula on exertional dyspnea in nonhypoxemic patients is unclear. In this double-blind, parallel-group, randomized trial, we assessed the effect of flow rate (high vs. low) and gas (oxygen vs. air) on exertional dyspnea in nonhypoxemic patients with cancer. PATIENTS AND METHODS: Patients with cancer with oxygen saturation >90% at rest and exertion completed incremental and constant work (80% maximal) cycle ergometry while breathing low-flow air at 2 L/minute. They were then randomized to receive high-flow oxygen, high-flow air, low-flow oxygen, or low-flow air while performing symptom-limited endurance cycle ergometry at 80% maximal. The primary outcome was modified 0-10 Borg dyspnea intensity scale at isotime. Secondary outcomes included dyspnea unpleasantness, exercise time, and adverse events. RESULTS: Seventy-four patients were enrolled, and 44 completed the study (mean age 63; 41% female). Compared with low-flow air at baseline, dyspnea intensity was significantly lower at isotime with high-flow oxygen (mean change, -1.1; 95% confidence interval [CI], -2.1, -0.12) and low-flow oxygen (-1.83; 95% CI, -2.7, -0.9), but not high-flow air (-0.2; 95% CI, -0.97, 0.6) or low-flow air (-0.5; 95% CI, -1.3, 0.4). Compared with low-flow air, high-flow oxygen also resulted in significantly longer exercise time (difference + 2.5 minutes, p = .009), but not low-flow oxygen (+0.39 minutes, p = .65) or high-flow air (+0.63 minutes, p = .48). The interventions were well tolerated without significant adverse effects. CONCLUSION: Our preliminary findings support that high-flow oxygen improved both exertional dyspnea and exercise duration in nonhypoxemic patients with cancer. (ClinicalTrials.gov ID: NCT02357134). IMPLICATIONS FOR PRACTICE: In this four-arm, double-blind, randomized clinical trial examining the role of high-flow nasal cannula on exertional dyspnea in patients with cancer without hypoxemia, high-flow oxygen, but not high-flow air, resulted in significantly lower dyspnea scores and longer exercise time. High-flow oxygen delivered by high-flow nasal cannula devices may improve clinically relevant outcomes even in patients without hypoxemia.

Peak Inspiratory Flows: Defining Repeatability Limits and a Predictive Equation for Different Inhalers.

BACKGROUND: Peak inspiratory flow (PIF) has been proposed as a measure to assess a patient's ability to use dry powder inhalers (DPIs). However, robust quality criteria to determine a repeatability limit for measuring PIF are lacking. RESEARCH QUESTIONS: What are the repeatability limits for measuring PIF? What is the relationship between PIF measured using the In-Check DIAL device at Diskus (GlaxoSmithKline; PIFD) and HandiHaler (Boehringer Ingelheim; PIFHH) resistances? STUDY DESIGN AND METHODS: Data from a randomized, controlled, phase 3 trial (study 0149; see Clinical Trial Registration data) were used to define repeatability limits for PIF. In addition, a model to characterize the relationship between PIF measured with the In-Check DIAL device at PIFD and PIFHH was defined using data from two randomized, controlled, phase 3 trials (studies 0128 and 0149). RESULTS: In study 0128, the mean values (SD) for PIF at zero resistance and PIFHH were 84.6 (33.4) and 57.3 (26.1) L/min, respectively. In study 0149, the mean values (SD) for PIFD and PIFHH were 42.4 (11.2) and 29.0 (8.3) L/min, respectively. At the mean level, the mean difference between measurement attempts for PIFD and PIFHH was small, < 5 and < 3 L/min, respectively. The repeatability limit was determined as 10 and 5 L/min for PIFD and PIFHH, respectively. Modeling the relationship between PIFD and PIFHH, after controlling for significant covariates, demonstrated that a PIFD value of 60 L/min was approximately equivalent to PIFHH of 40 L/min. INTERPRETATIONS: This analysis demonstrated that the two highest values of PIF using the In-Check DIAL device among three inspiratory efforts, met the repeatability limit. Altogether, these data provide guidance for measuring PIF against the simulated resistance of a specific DPI in clinical practice and research studies. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov; Nos.: NCT02518139 (study 0128) and NCT03095456 (study 0149); URL: www.clinicaltrials.gov.