Inhaler use in chronic obstructive pulmonary disease

Inhaler technique is a common problem, particularly in the elderly. We have assessed the ability to use seven common inhaler devices in 20 patients with chronic obstructive pulmonary disease (COPD). Techniques were taught in a standard fashion in random order and assessed immediately and one hour later by two observers. Fourteen patients had a fault that would result in no drug delivery at some time during the study, and such a fault occurred at some point for each inhaler device. These faults were most common with the diskhaler. Accuhaler, autohaler and turbohaler scored highest and diskhaler lowest. Overall scores declined by one hour after instruction. Patients ranked the metered dose inhaler and accuhaler highest for ease of use and preference. These results show that it is useful to have a small range of devices for patients with COPD and that it is important to review inhaler technique regularly.     

Pathophysiology of chronic obstructive pulmonary disease

The prevalence of COPD has increased as mortality from the two organ systems affected by the same risk factors of smoking, heart attacks and strokes, has decreased. Once diagnosed, COPD is progressive and may lead to disability, usually due to dyspnea, at a relatively early age (60 to 80 years of age). COPD is usually caused by destruction of the lung parenchyma or by disease affecting the airways. In most patients both processes exist simultaneously. Less often recognized is the fact that the disease does not affect all portions of the lung alike, which causes different physiologic behaviors in different parts of the lung. This article integrates the pathologic changes of COPD with the known adaptive and maladaptive consequences of those changes. An understanding of these changes should result in an increased capacity to comprehend the different therapeutic strategies that have been developed to decrease the symptoms and improve the well-being of patients with COPD.     

Pathophysiology of chronic obstructive pulmonary disease

Emphysema with bullae is a common feature of patients with chronic obstructive pulmonary disease. Central to the pathophysiology of emphysema is the presence of airflow obstruction and lung and chest hyperinflation. Because of the increased ventilatory demand and the need to maintain gas exchange, patients with emphysema increase their work of breathing. This article reviews the adaptive and maladaptive consequences of these changes. A rationale is given as to the possible mechanism by which surgery aimed at resecting hyperinflated portions of the lungs may be effective.     

Pharmacotherapy of chronic obstructive pulmonary disease

Despite a significant reduction in cigarette consumption, chronic obstructive pulmonary disease continues to be an important cause of mortality in the United States. COPD is characterized by progressive airflow obstruction which is punctuated by acute exacerbations. Nicotine substitution and use of bupropion have been shown to double long-term smoking cessation success. The combination of albuterol and ipratropium bromide produces a synergistic beneficial effect on pulmonary function and symptoms. Long-acting inhaled beta 2-agonists improve symptoms better than as needed albuterol. Oral corticosteroids appear to be helpful during acute exacerbations; however, the chronic use of steroids benefits only a minority of patients. Broad- spectrum antibiotics are indicated during acute exacerbations if there is increased sputum volume and purulence. System-oriented administration of pneumococcal and influenza vaccinations is more successful than provider or client-oriented approaches.     

Radiology of chronic obstructive pulmonary disease

This article reviews the radiologic manifestations and complications of chronic obstructive pulmonary disease, particularly those seen in association with emphysema. Current concepts on the pathogenesis of chronic obstructive pulmonary disease are discussed and related to findings on high-resolution CT scan and histologic examinations. Controversial issues concerning the detection and grading of emphysema using radiologic and physiologic tests are also addressed.     

Lung cancer and chronic obstructive pulmonary disease

Spirometry can predict lung health and monitor disease and response to therapy. This noninvasive test can and should be done regularly by primary care providers. It can identify patients at risk for lung cancer as well as heart attack and stroke. Patients with abnormal spirometric findings can be warned that airflow obstruction has begun, which may provide the motivation to quit smoking. Abnormal spirometry measurements correlate with all-cause mortality. Approaches to early diagnosis of lung cancer continue to expand. For example, use of the new fluorescent bronchoscope can increase diagnostic accuracy in lung cancer by highlighting lesions that are malignant or likely to be malignant. For now, however, identification of airflow obstruction with spirometry and follow-up with sputum cytology provide the widest benefit.     

Inpatient management of chronic obstructive pulmonary disease

Community research and clinical practice have shown that alcohol and drug use and depression are interrelated. Among Hispanics, acculturation may play a role in these relationships. To investigate these relationships as well as alcohol-related problems, we interviewed 288 Puerto Rican, Dominican, and Colombian men in early adulthood. No significant differences emerged in the proportions of abstainers across the three groups. Colombians drank significantly more frequently and had more alcohol-related problems than Dominicans. Dominicans were at least risk for and least likely to have alcohol-related problems. Puerto Ricans were much more likely to use drugs than the other Hispanic men. Drug use was associated with an increased likelihood of heavy drinking which, in turn, increased the risk of drug use and depression. Acculturation decreased the risk of drug use. Results are discussed in terms of implications for community psychology research and interventions.     

Non-invasive estimation of pulmonary arterial hypertension in chronic obstructive pulmonary disease

The feasibility and reliability of the combination of several noninvasive methods using a multivariate method of analysis to predict pulmonary artery hypertension (PAH) is evaluated in 20 patients with chronic obstructive pulmonary disease. These methods comprised arterial blood gases (Pao2, Paco2), pulmonary functional parameters (FEV1), echo-Doppler parameters (tricuspid regurgitation jets, acceleration time on pulmonary valve), computed tomography measurements (transhilar distance, hilar thoracic index, and measurement of the descending branch of the right pulmonary artery to the lower lobe). A multiple stepwise regression analysis (including one Doppler parameter, two parameters of arterial blood gases, and one functional parameter) revealed a coefficient of determination (R2) equal to 0.954 for mean pulmonary artery pressure (MPAP) with a standard error of estimate (S.E.E.) of 5.25 mmHg. A stepwise regression analysis including computed tomography and radiographic parameters revealed an R2 equal to 0.970 for PAP with a S.E.E. of 4.26 mmHg. Logistical regression analysis classified correctly 80% of patients with PAH using noninvasive methods such as the diameter of the main pulmonary artery and the diameter of the left pulmonary arterial branch calculated by computed tomography. Not only the presence of PAH but also the level of MPAP can be estimated by the combination of multiple stepwise and logistical regression analyses.     

Functional performance in people with chronic obstructive pulmonary disease

The extent to which individuals with a chronic physical illness perform their day-to-day activities and maintain the independence and autonomy they desire is both an indicator of adaptation and an important clinical outcome criterion. Yet the concept of functional performance is not well understood. Studies of people with chronic obstructive pulmonary disease (COPD) have attempted to identify physiologic and psychosocial factors that contribute to functioning in this population. These studies have used a melange of terms, including functional status, functional ability, quality of life, and health status interchangeably. They have also employed a variety of instruments to operationalize functional performance and an assortment of predictors to understand the phenomena. Perhaps as a result of this disarray, no attempt has been made to synthesize the literature for nursing research and practice. The purpose of this paper is to summarize the research on functional performance in people with COPD, indicate areas of understanding and quandary, suggest possible flaws, and propose several new directions for practice and research.     

Current trends and treatments in chronic obstructive pulmonary disease

Non-insulin-dependent diabetes mellitus (NIDDM) is a prototypical multifactorial disease. Genetic predisposition and obesity are major risk factors for NIDDM development and the interactions between these factors are likely to be important in the etiology of this disease. The Otsuka Long-Evans Tokushima Fatty (OLETF) rat is one of the best animal models of NIDDM, since the OLETF rat develops NIDDM with mild obesity that is very similar to human NIDDM. Therefore, the OLETF rat is a powerful model for investigating the interaction between genetic susceptibility to NIDDM and obesity. In this study, our goal was to clarify the relationship between an individual NIDDM susceptibility locus and obesity in the OLETF using a molecular genetics approach. We identified four novel quantitative trait loci (QTLs) that contribute to the susceptibility to NIDDM, none of which shows significant linkage with body weight. However, Nidd1/of on chromosome 7 and Nidd2/of on chromosome 14 have an interaction with body weight. In contrast, one locus was mapped to chromosome 10 for body weight, but not to fasting or postprandial glucose levels. These data illustrate that NIDDM and body weight are under separate genetic control in the OLETF yet interact to yield the final disease phenotype in the two Nidd/of loci. In addition, body weight could be used in place of body mass index as an indicator of obesity in our experimental system of genetic study. This study will facilitate the understanding of the complex interaction between genetic susceptibility to NIDDM and obesity.     

Cellular adaptations in the diaphragm in chronic obstructive pulmonary disease

BACKGROUND: In patients with severe chronic obstructive pulmonary disease, the diaphragm undergoes physiologic adaptations characterized by an increase in energy expenditure and relative resistance to fatigue. We hypothesized that these physiologic characteristics would be associated with structural adaptations consisting of an increased proportion of less-fatigable slow-twitch muscle fibers and slow isoforms of myofibrillar proteins. METHODS: We obtained biopsy specimens of the diaphragm from 6 patients with severe chronic obstructive pulmonary disease (mean [+/-SE] forced expiratory volume in one second, 33+/-4 percent of the predicted value; residual volume, 259+/-25 percent of the predicted value) and 10 control subjects. The proportions of the various isoforms of myosin heavy chains, myosin light chains, troponin, and tropomyosin were determined by sodium dodecyl sulfate-polyacrylamide-gel electrophoresis. We also used immunocytochemical techniques to determine the proportions of the various types of muscle fibers. RESULTS: The diaphragm-biopsy specimens from the patients had higher percentages of slow myosin heavy chain I (64+/-3 vs. 45+/-2 percent, P<0.001), and lower percentages of fast myosin heavy chains IIa (29+/-3 vs. 39+/-2 percent, P=0.01) and IIb (8+/-1 vs. 17+/-1 percent, P<0.001) than the diaphragms of the controls. Similar differences were noted when immunohistochemical techniques were used to compare the percentages of these fiber types in the two groups. In addition, the patients had higher percentages of the slow isoforms of myosin light chains, troponins, and tropomyosin, whereas the controls had higher percentages of the fast isoforms of these proteins. CONCLUSIONS: Severe chronic obstructive pulmonary disease increases the slow-twitch characteristics of the muscle fibers in the diaphragm, an adaptation that increases resistance to fatigue.     

Occlusion pressure responses in asthma and chronic obstructive pulmonary disease

During CO2 rebreathing we measured ventilation and the pressure generated during the first 0.1 sec of inspiratory effort against a closed airway (P 0.1) in 12 asthmatics during acute exacerbation, 10 normal subjects, and 10 patients with chronic obstructive pulmonary disease. In normal subjects, the ventilatory responst to CO2 correlated with the P 0.1 response measured as delta In P 0.1. Patients with chronic obstructive pulmonary disease showed depressed responses to CO2 in terms of both ventilation and deltaIn P0.1. However, P 0.1 values in the patients with chronic obstructive pulmonary disease were greater than those of the normal subjects when they were compared at an alveolar PCO2 of 60 mm Hg. Asthmatics' responses to CO2 were similar to those of patients with chronic obstructive pulmonary disease. When measured at an alveolar PCO2 of 60 mm Hg, asthmatics' P 0.1 values were greater than those of both normal subjects and patients with chronic obstructive pulmonary disease. As the asthmatics' airway obstruction decreased so did their P 0.1. The asthmatics, and to a lesser extent the patients with chronic obstructive pulmonary disease, demonstrated increased inspiratory muscle activity that could not be explained on the basis of chemical drive or alterations in functional residual capacity. In the case of the asthmatics it was possible that the increased inspiratory muscle activity was a response to airway obstruction.