摘要:

Difficulty with sleep is a common complaint in patients with chronic obstructive pulmonary disease (COPD). The reasons are complex, having to do with the disease itself as well as with medications prescribed. Significant sleep-related oxyhemoglobin desaturations occur in only a small population of COPD patients. When present, however, significant morbidity may occur.Nocturnal hypoxemia in COPD patients may occur during any stage of sleep, but it is most commonly found during rapid eye movement sleep. This is due, in part, to the muscle atonia that accompanies rapid eye movement sleep, as well as to a blunted hypoxic response, a reduced functional residual capacity, and worsening ventilation/perfusion mismatch. This sleep-related hypoxemia can lead to impaired sleep quality, cardiac arrhythmias, pulmonary hypertension, and even death during sleep. Coexistent sleep apnea can clearly lead to additional complications. Overnight sleep studies should be performed on COPD patients whose awake, resting Pao2is2is >55 torr but who have signs of pulmonary hypertension, right-sided heart failure, or polycythemia. Those with symptoms of obstructive sleep apnea should also be studied. Overnight oximetry can be used to titrate oxygen therapy.Nocturnal oxygen therapy has been shown to benefit survival and lead to enhanced sleep quality. Nasal nocturnal ventilation is most beneficial for those with the most severe desaturations or those with coexistent obstructive sleep apnea/hypopnea syndrome. Awareness of sleep disorders in COPD patients should prompt pulmonologists to ask patients about sleep quality, and sleep studies should be conducted when appropriate.

ISSN:1068-0640    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

The incidence of antibiotic resistance is increasing in pneumococcal isolates worldwide. Current evidence suggests that the most active 13-lactam agents remain clinically useful in the treatment of penicillin-resistant pneumococcal pneumonia. These agents include intravenous penicillin, amoxicillin, cefuroxime, the third-generation cephalosporins cefotaxime and ceftriaxone, and the carbapenems. The authors recommend that penicillin or amoxicillin remain the drugs of choice for this condition. Macrolide resistance has been associated with clinical failure. The clinical relevance of resistance to trimethoprim/sulfamethoxazole has yet to be established. Most of the currently available quinolones are of borderline activity against the pneumococcus and would not be recommended for empiric therapy. Antibiotic-resistant pneumococci are increasingly found among HIV-infected patients. The therapeutic outcome appears, however, to be similar to that of patients without HIV infection.

ISSN:1068-0640    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Welding produces a variety of substances toxic to the respiratory tract. A thorough occupational history, based on an understanding of the various work processes, is essential to the prompt identification of potential welding-associated hazards. Several key questions can establish if the worker has been exposed to some of the more potent airborne emissions from welding. Although this trade is not associated with extraordinary morbidity and mortality in occupational health statistics, a wide variety of acute and chronic respiratory disorders are recognized. There is considerable overlap in the presentation of several of the acute disorders, frequently posing a diagnostic dilemma. The health hazards of welding are changing with the evolution of increasingly sophisticated technologies. Although exposure to welding fumes in general is associated with a 30% to 40% increased mortality from lung cancer, it remains controversial whether or not stainless steel welders are at heightened risk.

ISSN:1068-0640    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Palatal surgery has been the traditional surgical therapy for sleep apnea hypopnea syndrome (SAHS) since 1981 when uvulopalatopharyngoplasty (UPPP) was first reported and subsequently replaced permanent tracheostomy as the mainstay of surgical management for this disorder. Over the past decade, as a more complete understanding of the pathophysiology of SAHS has developed, it has become clear that routine UPPP provides ineffective treatment for many patients with SAHS. When a clinically relevant definition of therapeutic success is used, such as reduction in apneas and hypopneas to a level achieved with optimal positive airway pressure therapy, cure rates for obstructive sleep apnea after UPPP are consistently below 50%. The low UPPP success rate may be attributable to airway collapse in one or more sites in the upper airway other than the soft palate. Therefore, surgical procedures that address multiple sites of airway collapse are needed. Nonpalatal surgical procedures that accomplish this are described, as are several new techniques in palatal surgery and their indications and limitations. Preoperative evaluation of the upper airway emphasizing direct nasopharyngoscopy with Mill-lees maneuver, as well as other techniques, to determine potential sites of airway collapse is discussed. The importance of objective testing and longitudinal care of these patients is emphasized.

ISSN:1068-0640    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Oxygen is a commonly used therapy for a wide variety of cardiopulmonary disorders. It is effective in reversing arterial hypoxemia from all causes except pure venoarterial shunting. In the vast majority of patients, oxygen therapy is safe. Oxygen toxicity has been well studied in animal models, which have led to a detailed understanding of morphology, pathogenesis, and treatment of this form of acute lung injury. In contrast, there remain significant gaps in the understanding of oxygen toxicity in humans. Pulmonary oxygen toxicity in humans is most likely to occur in the intensive care unit setting when patients are exposed to high concentrations of oxygen for prolonged time intervals. These patients usually have acute lung injury and other concurrent illnesses making it difficult to extrapolate information from animal studies and normal humans. There are no currently available techniques to diagnose oxygen toxicity in these patients, and there are no definitive guidelines for what constitutes a “safe” amount of oxygen exposure. The besttreatmentisprevention, which consists of limiting oxygen exposure to the lowest Frog that supports a Pao2of 55 to 60 tort Clinical experience suggests that this strategy is usually effective and raises questions about the importance of oxygen toxicity in critically ill patients. It is possible that the lungs of critically ill patients are better able to withstand the injurious effects of oxygen than nonnal lungs. This artide summarizes information about nomiobaric oxygen toxicity obtained from animal models and humans and addresses controversies that relate to oxygen therapy in critically ill patients.

ISSN:1068-0640    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

There are two general types of pulmonary atelectasis, compressive and resorptive. Fundamental differences between the pathophysiology of these two forms are reflected in the different radiographic appearances of each. This review will provide a basis to recognize atelectasis and to distinguish lobar collapse from resorptive atelectasis on a standard posteroanterior and a lateral chest radiograph. A systematic approach to evaluating chest radiographs is advised based on three questions: Do the lungs, or does a lung, appear small? Are thoracic or extrathoracic structures shifted from their usual position? Is there a characteristic soft tissue density pattern within the lungs? Atelectasis may be identified directly by making an assessment of reduced lung volume on the standard chest radiograph and indirectly inferred by shifts of thoracic and extrathoracic structures from their usual positions. Increased soft tissue density is also an integral component of lobar atelectasis. As residual air is resorbed and the lobe collapses, the soft tissue component of the lobe projects a characteristic pattern on the posteroanterior and the lateral chest roentgenogram. Recognizing lobar collapse on the standard posteroanterior and the lateral chest radiograph should lead to further diagnostic techniques for evaluating the patency of the proximal tracheobronchial tree.

ISSN:1068-0640    

出版商:OVID    

年代:1997

数据来源: OVID

ISSN:1068-0640    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

The pulmonary vasculature is in a relatively inaccessible location, and this may be why there are so many unanswered questions in the study of diseases that affect this site, for example, primary pulmonary hypertension (PPH). PPH seems to be defined by a characteristic pathology in the lungs without a specific cause. Nevertheless, several specific events seem relevant to the pathogenesis of PPH, induding pulmonary vasoreactivity, migration of smooth musde cells from the vascular media into the intima, and an endothelial injury or dysfunction. This review will examine management of PPH and divide it into six categories. Anticoagulation has been shown to be beneficial in PPH it prolongs life. Because hypoxic pulmonary vasoconstriction may be superimposed on PPH, relieving it with supplemental oxygen is important in reducing the afterload of the already taxed right ventride. Although drug-induced vasodilation has been a focus of clinical research in PPH for the past 16 years, it has never been condusively shown to prolong life in this condition. Interestingly, prostacydin, studied for many years for its vasodilator properties, should now be used in the treatment of PPH because of its ability to improve survival via mechanisms other than vasodilation, that is, de-remodeling. Lung transplantation is an option for some patients, and early results have been encouraging. Reversal of the pathologic lesions of vascular remodeling in PPH may be within reach in the next decade using treatment with endothelially derived mediators, for example, nitric oxide and pmstacydin.

ISSN:1068-0640    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

A case is presented of a ruptured splenic artery aneurysm in a 49-year-old patient with known al-antitrypsin deficiency. The possible etiologic implications of arantitrypsin deficiency in the pathogenesis of aneurysmal disease and a brief review of the nonpulmonary manifestations of arantitrypsin deficiency are discussed.

ISSN:1068-0640    

出版商:OVID    

年代:1997

数据来源: OVID

ISSN:1068-0640    

出版商:OVID    

年代:1997

数据来源: OVID