Susan J. Corbridge

Autotaxin Production of Lysophosphatidic Acid Mediates Allergic Asthmatic Inflammation

RATIONALE Bioactive lipid mediators, derived from membrane lipid precursors, are released into the airway and airspace where they bind high-affinity cognate receptors and may mediate asthma pathogenesis. Lysophosphatidic acid (LPA), a bioactive lipid mediator generated by the enzymatic activity of extracellular autotaxin (ATX), binds LPA receptors, resulting in an array of biological actions on cell proliferation, migration, survival, differentiation, and motility, and therefore could mediate asthma pathogenesis. OBJECTIVES To define a role for the ATX-LPA pathway in human asthma pathogenesis and a murine model of allergic lung inflammation. METHODS We investigated the profiles of LPA molecular species and the level of ATX exoenzyme in bronchoalveolar lavage fluids of human patients with asthma subjected to subsegmental bronchoprovocation with allergen. We interrogated the role of the ATX-LPA pathway in allergic lung inflammation using a murine allergic asthma model in ATX-LPA pathway-specific genetically modified mice. MEASUREMENTS AND MAIN RESULTS Subsegmental bronchoprovocation with allergen in patients with mild asthma resulted in a remarkable increase in bronchoalveolar lavage fluid levels of LPA enriched in polyunsaturated 22:5 and 22:6 fatty acids in association with increased concentrations of ATX protein. Using a triple-allergen mouse asthma model, we showed that ATX-overexpressing transgenic mice had a more severe asthmatic phenotype, whereas blocking ATX activity and knockdown of the LPA2 receptor in mice produced a marked attenuation of Th2 cytokines and allergic lung inflammation. CONCLUSIONS The ATX-LPA pathway plays a critical role in the pathogenesis of asthma. These preclinical data indicate that targeting the ATX-LPA pathway could be an effective antiasthma treatment strategy.

Online learning versus simulation for teaching principles of mechanical ventilation to nurse practitioner students.

Patient simulation is increasingly used in the education of healthcare providers, yet few studies have compared simulation to other teaching modalities. The purpose of this study was to determine differences in knowledge acquisition and student satisfaction between two methods of teaching the principles of mechanical ventilation to advanced practice nursing (APN) students: high-fidelity patient simulation (including face-to-face instruction) versus an online, narrated PowerPoint presentation. Twenty APN students were randomized to either the simulation or online teaching method in this pre/posttest study. Measures included a 12-item knowledge questionnaire and a 5-item satisfaction survey. Both groups had significant improvement in knowledge scores from pretest to posttest, but knowledge scores were not significantly different at posttest between groups. Student satisfaction with their learning method was significantly higher in the simulation group. Students choosing to participate in the alternative teaching method after study completion preferred the simulation to the online method.

Nurses' knowledge of inhaler technique in the inpatient hospital setting.

Purpose/Objectives: High rates of inhaler misuse in patients with chronic obstructive pulmonary disease and asthma contribute to hospital readmissions and increased healthcare cost. The purpose of this study was to examine inpatient staff nurses’ self-perception of their knowledge of proper inhaler technique compared with demonstrated technique and frequency of providing patients with inhaler technique teaching during hospitalization and at discharge. Design: A prospective, descriptive study. Setting: A 495-bed urban academic medical center in the Midwest United States. Sample: A convenience sample of 100 nurses working on inpatient medical units. Methods: Participants completed a 5-item, 4-point Likert-scale survey evaluating self-perception of inhaler technique knowledge, frequency of providing patient education, and responsibility for providing education. Participants demonstrated inhaler technique to the investigators using both a metered dose inhaler (MDI) and Diskus device inhaler, and performance was measured via a validated checklist. Findings: Overall misuse rates were high for both MDI and Diskus devices. There was poor correlation between perceived ability and investigator-measured performance of inhaler technique. Frequency of education during hospitalization and at discharge was related to measured level of performance for the Diskus device but not for the MDI. Conclusions: Nurses are a key component of patient education in the hospital; however, nursing staff lack adequate knowledge of inhaler technique. Implications: Identifying gaps in nursing knowledge regarding proper inhaler technique and patient education about proper inhaler technique is important to design interventions that may positively impact patient outcomes. Interventions could include one-on-one education, Web-based education, unit-based education, or hospital-wide competency-based education. All should include return demonstration of appropriate technique.

Implementing team-based learning in a nurse practitioner curriculum.

Team-based learning (TBL) is an innovative, learner-centered teaching strategy that promotes active learning. The authors describe their experience with implementing TBL in an adult-gerontology acute and primary care course for nurse practitioners as well as their evaluation of student outcomes.

Inspiratory muscle strength in chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease is associated with a functional weakness of the inspiratory muscles. Multiple factors contribute to the decline in functional strength including hyperinflation of the chest, deterioration in nutritional status, and the indirect effects of an exacerbation. The decreased inspiratory muscle strength contributes to sensations of dyspnea and places individuals at risk for respiratory muscle fatigue. The worsening dyspnea causes individuals to reduce their physical activities and ultimately become physically deconditioned. Maximal inspiratory pressure is commonly used to measure functional strength of the inspiratory muscles, and interventions to minimize the extent of decline include inspiratory muscle training, aerobic exercise training, nutritional supplementation, and methods to prevent exacerbations. In the critical care unit, multiple comorbid conditions contribute to further decline in inspiratory muscle strength, making it important to assess respiratory muscle function regularly.

Asthma in adolescents and adults.

OVERVIEW:More than 16 million U.S. adults have asthma, a condition that prompts 2 million ED visits and nearly half a million hospital admissions annually. Management of this potentially deadly, chronic inflammatory disease depends on early diagnosis, accurate classification, appropriate treatment, and targeted patient education. This article outlines current guideline recommendations for asthma and reviews what clinicians need to teach patients about its pathophysiology, pharmacotherapy, self monitoring, and environmental control. The authors discuss the classic clinical presentation of the disease, describe how to assess severity and control, and explain how such assessments can guide management.

COPD Exacerbations: Evidence-based guidelines for identification, assessment, and management.

Overview Chronic obstructive pulmonary disease (COPD) is the third leading cause of death in the United States. Its estimated that more than 13 million U.S. adults have COPD, and as many as 24 million have evidence of impaired lung function, suggesting that COPD is underdiagnosed. Even when patients receive optimal COPD therapy, they periodically experience exacerbations, which reduce lung function and quality of life, increase risk of death from COPD, and account for the majority of costs related to COPD treatment. This article, the second in a two-part series on COPD, outlines current guidelines and evidence-based recommendations for identifying, assessing, and managing COPD exacerbations (the first article in the series, “An Evidence-Based Approach to COPD,” March 2012, focused on the management of stable COPD in the outpatient setting).

Effective management of ARDS

Acute respiratory distress syndrome is a serious complication of critical illness that is associated with high morbidity and mortality. There are no effective treatment options, so prevention, early recognition, and appropriate supportive care are essential to improve outcomes. This article provides an overview of the disorder, including current treatment considerations.

Implementation of an interprofessional educational model.

Despite literature that supports the benefits of interprofessional collaboration among healthcare practitioners, such as better patient outcomes and more efficient use of resources, many education programs continue to educate in silos, leading to a lack of awareness of the role of other disciplines. The nurse practitioner role, as example, requires positive collaboration with other healthcare providers, including physicians. The authors describe the development, implementation, and evaluation of an innovative interprofessional clinical educational model that was integrated into a nurse practitioner curriculum, as well as lessons learned during the first 2 years this program has been in place.

An evidence-based approach to COPD: part 1.

OVERVIEWChronic obstructive pulmonary disease (COPD) is the third leading cause of death in the United States, affecting as many as 24 million Americans and resulting in 1.5 million ED visits, 700,000 hospital admissions, and 124,000 deaths annually. This article, the first in a two-part series on COPD, outlines current guidelines and other evidence-based recommendations on diagnosing and managing stable COPD in the outpatient setting. Part 2 will appear in a future issue of AJN and will focus on managing acute exacerbations of COPD.