摘要:

Mucus retention is usually due to both hypersecretion and impaired clearance. Infected secretions induce inflammation, and this can further damage the airway. To break this cycle, efforts are made to reduce the secretion burden. To choose appropriate therapy, it is important to understand the secretion properties and the mechanism of action of mucoactive medications. Expectorants are postulated to increase the volume or hydration of airway secretions. Systemic hydration and classic expectorants have not been shown to be clinically effective. Modifiers of airway water transport including tricyclic nucleotides are now being investigated as expectorants. Mucolytics degrade polymers in secretions. Classic mucolytics have free thiol groups to degrade mucin and peptide mucolytics break pathologic filaments of neutrophil-derived DNA and actin in sputum. These appear to be effective in chronic inflammatory airway diseases. Mucokinetics are agents that increase mucociliary or cough efficiency. Cough flow can be increased by bronchodilators in patients with airway hyperreactivity. Abhesives such as surfactants decrease epithelial-mucus attachment, augmenting both cough and mucociliary clearance. Mucoregulatory agents reduce the volume of mucus secretion and seem to be especially effective in hypersecretory states such as bronchorrhea and diffuse panbronchiolitis. These medications include antiinflammatory agents, anticholinergic agents, and some macrolide antibioticsPatients most likely to benefit from mucoactive therapy usually have a history of increased sputum expectoration and preserved airflow. With the possible exception of external chest wall oscillation, most clearance assistive devices and mucoactive medications seem to be less beneficial in patients with severe lung disease. However, therapeutic efficacy can be difficult to assess in an individual patient. When the patient feels better and there is an improved airflow, benefit is clear. The expectorated sputum volume relates poorly, at best, to improvement in pulmonary function or the clinical status of the patient. There is significant controversy regarding clinically relevant outcome measurement for clinical trials of mucoactive agents.

ISSN:1068-0640    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Immunoglobulins (Igs) are the products of activated B lymphocytes and are the effector limb of the humoral component of the immune system. IgG, which is found in the highest concentration in serum, is further subdivided into four subclasses: IgGl, IgG2, IgG3, and IgG4, which have different functions. Deficiencies of the IgG subclasses have been recognized for nearly 30 years. Despite extensive research, much is yet unknown, and the exact role that these deficiencies play in the pathogenesis of various respiratory disorders is uncertain. In certain conditions, elevated levels of individual subclasses may occur and may also be associated with harmful effects.Alterations in IgG subclass levels (both increases and decreases) have been noted in a number of respiratory diseases including recurrent infections, community-acquired pneumonia, various forms of obstructive airways disease, cystic fibrosis, and interstitial lung disease. Future research still needs to clarify the role of deficiencies of subclasses in various well-defined clinical syndromes before the true value of Ig replacement therapy can be assessed by appropriately controlled studies.

ISSN:1068-0640    

出版商:OVID    

年代:1998

数据来源: OVID

ISSN:1068-0640    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

The increasing use of high-resolution CT (HRCT) should lead to a reconsideration of the traditional manner in which patients with diffuse interstitial lung disease are evaluated. HRCT is no longer used only in the assessment of rare diseases or exclusively in academic medical centers.There are many clinically important uses of HRCT in patients with pulmonary symptoms; in some cases, the imaging findings are diagnostic and obviate tissue diagnosis. The frequency with which this occurs depends on the type and stage of disease present and on the skill and confidence of the individual interpreting the images. Accurate HRCT interpretation also requires correlation with clinical information.The diagnostic evaluation of patients with known or suspected lung disease should involve pulmonologists, thoracic radiologists, and thoracic surgeons.Clin Pulm Med 1998;5(1):23–35

ISSN:1068-0640    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Thoracic injuries are responsible for approximately 25|X% of deaths from trauma and contribute to mortality in an additional 25|X% of cases. In spite of this, only 15|X% of chest injuries require operative treatment. Most patients can be managed with relatively simple maneuvers, including supplemental oxygen administration, adequate volume resuscitation, and chest tube placement. Critical adjunctive measures include aggressive chest physiotherapy and appropriate pain control. This article focuses on the sequelae of blunt pulmonary injury with particular emphasis on those directly related to the pulmonary system.

ISSN:1068-0640    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

The term “outcomes research” grew out of the research literature on the quality of medical care, which postulated that the quality of medical care can be assessed in terms of the structure, process, and outcome of care. Whereas early research on quality of care focused on structure and process measures, the assessment of patient-oriented health outcomes has recently emerged as a prominent area of research. Interest in this area reflects in part a growing acknowledgment that the mere provision of services does not ensure their appropriateness and that treatment efficacy may not predict treatment effectiveness. Understanding the results of outcomes research may be hampered by the fact that many of the measures involved could be used to assess both the process of care as well as its outcome. Health care utilization measures for chronic diseases, for instance, may be divided into process-oriented measures of ongoing “chronic” care and outcome-oriented measures of “acute” care. Generally speaking, what determines the difference between process research and outcomes research is determined by the purpose of the study. Outcomes research can also be viewed as an integral part of ongoing quality assurance, a cyclical process in which data are collected to test hypotheses about the effectiveness of the health care process and the results of such analyses are used to refine the process of care delivery.

ISSN:1068-0640    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Pain and agitation are common problems among critically ill patients, and achieving adequate relief of these symptoms often presents a difficult challenge in the intensive care unit (ICU). Analgesics and sedative drugs are invaluable in the treatment of agitated patients in the ICU, once organic causes of delirium and agitation have been eliminated. An understanding of the causes of agitation in the ICU, as well as an understanding of the altered physiology of critically ill patients, should lead to the appropriate use of analgesics and sedatives. Although fear of the side effects of analgesics and sedatives often limits their use, undertreatment of agitation and excessive motor activity can have equally deleterious effects.On occasion in patients being mechanically ventilated, sedation alone is not adequate to achieve synchrony between the patient and the ventilator, and neuromuscular blocking agents are required. As with analgesics and sedatives, an understanding of their use in critically ill patients is imperative. Patients receiving neuromuscular blocking agents must be routinely evaluated, both for the depth of neuromuscular blockade and for the adequacy of sedation and pain relief.Properly used, analgesics, sedatives, and neuromuscular blocking agents are very effective and safe drugs in the ICU. Knowledge of the different classes of these drugs and their indications, contraindications, and dosing in critically ill patients is necessary to achieve optimum benefit from their use.

ISSN:1068-0640    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Obstructive sleep apnea (OSA) is a common disorder in middle-aged adults that remains underrecognized and underdiagnosed in the community. Symptomatology and patient characteristics such as obesity and hypertension increase the clinical likelihood of OSA, but the diagnosis of OSA requires confirmation by overnight polysomnography. Portable, unattended monitoring systems promise a more cost-effective alternative to polysomnography, but their efficacy in the diagnosis of OSA is still unclear. The decision to treat patients with OSA is based on the integration of the objective severity of disease, the presence of cardiovascular risk factors, and the severity of daytime symptoms.Treatment of OSA should aim to abolish all apneic activity and arousals because of respiratory events and to normalize sleep architecture because of upper airways obstruction. Conservative measures such as weight loss and alcohol avoidance are advisable for all patients. Nasal continuous positive airway pressure is the treatment of choice for moderate to severe OSA, but patient acceptance and compliance remain suboptimal. Site-specific surgery such as uvulopalatopharyngoplasty may be useful in selected patients, but there is no reliable test at present to localize the site of obstruction preoperatively and to predict treatment success. The recent introduction of oral appliances provides a treatment option for mild to moderate OSA patients who cannot tolerate continuous positive airway pressure; however, long-term efficacy is unknown.

ISSN:1068-0640    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Liver transplantation (LT) is an established form of therapy for selected patients with a variety of liver diseases. More than 7000 new transplants are performed around the world every year with a 5-year survival approaching 70|X%. Pulmonary complications of various degrees develop in 40|X% to 75|X% of LT recipients and account for significant mortality and morbidity. This article reviews the different infectious pulmonary complications of LT including bacterial, fungal, viral, tuberculous, and protozoal infections; in addition, there are a variety of noninfectious problems such as pulmonary edema, atelectasis, pleural effusion, pulmonary calcifications, and posttransplantation malignancy. This review outlines the relative frequency, risk factors, clinical manifestations, and the diagnostic approach to these complications. In appropriate instances, therapeutic and prophylactic strategies are also discussed.

ISSN:1068-0640    

出版商:OVID    

年代:1998

数据来源: OVID

ISSN:1068-0640    

出版商:OVID    

年代:1998

数据来源: OVID