摘要:

The management of asymptomatic or minimally symptomatic non-small cell lung cancer in patients with severe underlying chronic obstructive pulmonary disease poses a frequent and difficult challenge for the pulmonary practitioner. The therapeutic strategies most commonly used at present include limited surgery, radiotherapy, or observation until distressing symptoms arise. In addition, laser photoresection may be suitable for a few highly selected patients. In this review, salient aspects of each approach are considered. Limited data suggest that carefully planned surgery or radiotherapy are reasonably safe and effective and preferable to expectant management for most patients with concomitant non-small cell lung cancer and severe chronic obstructive pulmonary disease. Treatment (as opposed to expectant management) is also supported by a consideration of the natural history of the two diseases. Recent developments in thoracic surgery (including tumor resection in conjunction with volume reduction) suggest that no patient should be dismissed from surgical consideration based solely on pulmonary function criteria. Nevertheless, management is ultimately predicated on a careful weighing of the particular clinical circumstances that uniquely pertain to each individual.

ISSN:1068-0640    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

Pneumocystis cariniipneumonia (PCP) remains a frequent cause of morbidity and mortality in immunosuppressed patient populations despite the introduction of primary prophylaxis in patients at risk. The available spectrum of therapy in the management of PCP has widened in the last few years. Sulfamethoxazole/ trimethoprim (TMP-SMZ) remains the drug of choice for both prophylaxis and treatment. However, in a significant proportion of patients (especially HIV-infected patients), severe adverse events may limit the clinical utility of this regimen. For prophylaxis in TMP-SMZ-intolerant patients, either inhaled pentamidine or dapsone may be used, although both regimens are less efficacious. Clindamycin/primaquine is becoming the second drug of choice for treatment of mild-to-moderate PCP, because this regimen seems to be less toxic, may be given orally, and is presumably as efficacious as TMP-SMZ. Atovaquone is an alternative therapeutic agent with potent in vitro efficacy againstP. cariniiandToxoplasma gondii,but may be limited by variable bioavailability in vivo. Pentamidine is currently being questioned as the second-choice drug in the treatment of PCP because of concerns about toxicity and inadequate efficacy. Trimetrexate with leucovorin protection may be used for all (including severe) cases of PCP intolerant to standard treatment. This regimen is less toxic but also less efficacious than TMP-SMZ in moderate-to-severe PCP. All patients with moderate-to-severe PCP should receive adjunctive corticosteroid treatment. Further research should be directed toward the discovery of more effective and orally administered regimens for PCP management. Clin Pulm Med 1996;3(6):304–313

ISSN:1068-0640    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

Lung disease in scleroderma is a major cause of morbidity and mortality. The two most common forms are pulmonary fibrosis and pulmonary hypertension, and both are difficult to detect at an early stage. With late detection, therapeutic attempts are difficult due to the development of end-stage irreversible disease. Methods for early detection are being studied and include high-resolution computed tomography and bronchoalveolar lavage. Medication trials have yielded varying results, with many studies involving a small number of patients and being open trials. The most promising results of therapy derive from three studies of cyclophosphamide, each of which demonstrated an improvement in pulmonary function in scleroderma patients with interstitial lung disease. Vasodilator therapy has been evaluated and more recent studies include infusions of prostacyclin and its analogs for the treatment of pulmonary hypertension. Single lung transplantation has also been used in a few patients, but controlled trials are needed to determine if any of these therapies can lead to significant improvement in the morbidity and mortality of scleroderma lung disease.

ISSN:1068-0640    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

Respiratory tract infections and their treatment are associated with an enormous burden on the health care system. Economic considerations are therefore extremely important in making therapeutic decisions regarding antibiotic prescriptions in particular, and a systematic framework is required to fully evaluate the costs and outcomes resulting from therapeutic choices. There are four types of economic evaluations: cost minimization, cost-effectiveness, cost benefit, and cost utility, and each is appropriate in different situations depending on the magnitude and type of outcome measured. Designs of studies to gather economic data alongside clinical outcomes range from clinical trials to decision analytic models. Three examples of differing therapeutic situations in respiratory tract infections are discussed to highlight the application of these principles.

ISSN:1068-0640    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

Because tissue hypoxia plays a major role in the morbidity and mortality of critically ill patients, achieving adequate tissue oxygenation is considered the main goal in the intensive care unit during initial management of patients with shock, severe sepsis, trauma, and the multiorgan dysfunction syndrome. Unfortunately, systemic parameters of tissue oxygenation are not reliable enough to represent “true” tissue oxygenation status. Methods developed to monitor oxygen tissue metabolism, such as phos-phorus-31 nuclear magnetic resonance, near-infrared spectroscopy, and tissue Po2electrodes are still far from clinical application. A new approach to this problem is the measurement of gastric intramucosal pH (pHi) with a gastric tonometer. This device consists of a modified nasogastric tube attached to a silicone balloon that is filled with saline. After an equilibration period, saline solution can be sampled and its Pco2measured in a blood-gas analyzer. Arterial bicarbonate is simultaneously measured. Gastric pHi is then easily calculated using the Henderson-Hasselbalch equation. Its value has been experimentally validated, comparing it with direct electrode tissue pH measurements. A growing body of evidence supports its clinical value at the present time. Several clinical investigations show that pHi is a sensitive and specific prognostic marker. Gastric pHi behavior is able to predict multiorgan dysfunction and mortality in different groups of critically ill patients. Its use to guide resuscitation maneuvers could contribute to mortality reduction. From the few years of basic and clinical research in which this technique has been used, it appears to be a useful tool to assess tissue oxygenation status.

ISSN:1068-0640    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

Sleep-disordered breathing (including obstructive sleep apnea and nocturnal hypoventilation) is a significant cause of morbidity and mortality among patients with neuromuscular and chest wall disorders. Rapid eye movement sleep is associated with a significant decrease in skeletal muscle tone. Therefore, the intercostal muscles are no longer available to assist with inspiration, and the pharyngeal muscles are floppier. The former is thought to lead to hypoventilation in the presence of compromised diaphragm function and thus significant oxygen desaturation during rapid eye movement sleep. The latter may exacerbate obstructive sleep apnea. Central sleep apnea has also been described in patients with myotonic and muscular dystrophy. Sleep studies are indicated in patients with symptoms of nocturnal hypoventilation including disrupted sleep, excessive daytime sleepiness, morning headache, altered concentration, memory, or personality, and awakenings with shortness of breath and choking. Additionally, asymptomatic patients with a reduced maximal inspiratory pressure or a forced vital capacity ≦ 1 to 1.5 liters or hypercarbia and hypoxemia on daytime arterial blood gases should undergo nocturnal sleep evaluation. For patients with nocturnal hypoventilation, treatment with noninvasive positive pressure ventilation is the treatment of choice. Negative pressure ventilators and other ventilatory-assist devices remain an option for those who do not have obstructive sleep apnea and cannot tolerate noninvasive positive pressure ventilation

ISSN:1068-0640    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

Given the rarity of mediastinal fibrosis, most reports are retrospective series of cases. Because of the belief by some that mediastinal fibrosis and mediastinal granuloma are one entity, many publications make no attempt to stratify the patients, leading to significant discrepancies in the reported clinical course and prognosis. Clinicopathologic correlations suggest that mediastinal fibrosis is an invasive process that causes impairment of mediastinal structures, whereas mediastinal granuloma is a more benign entity. It is unknown whether mediastinal granuloma progresses to fibrosis. Patients with mediastinal fibrosis present with symptoms related to the invasion of mediastinal structures, most frequently airway obstruction. Occlusion of pulmonary arteries and veins may cause symptoms resembling thromboembolic disease. The most common cause of mediastinal fibrosis is infection with Histoplasma capsulatum. Histopathologic analysis often suggests a prior infection with H. capsulatum, yet cultures are usually negative, arguing against an active infection. Mediastinal fibrosis is often misdiagnosed, compromising treatment, which is limited. Antifungal agents and steroids have minimal value; surgery is technically difficult and associated with a high mortality. Alternatively, surgery for mediastinal granuloma is safe and effective

ISSN:1068-0640    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

SynopsisPersistently symptomatic asthmatics who are on maintenance inhaled steroids improved more when salmeterol was added than when the inhaled steroid dose was doubled.SourceWoolcock A et al. Comparison of addition of salmeterol to inhaled steroids with doubling of the dose of inhaled steroids. Am f Respir Crit Care Med 1996;153:1481–8.

ISSN:1068-0640    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

SynopsisA 12-week postexposure cohort study compared molecular techniques with conventional diagnostic methods in the evaluation of health care personnel who were exposed to a patient with multidrug-resistant tuberculosis (MDR-TB). Both molecular and conventional testing showed that no health care personnel were infected, but molecular test results were available sooner and appeared to be more sensitive.SourceCockerill FR et al. Prospective evaluation of the utility of molecular techniques for diagnosing nosocomial transmission of multidrug-resistant tuberculosis (MDR-TB). Mayo Clin Proc 1996;71:221–9.

ISSN:1068-0640    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

SynopsisIn an open, prospective study, capnography was able to rule out clinically significant hypercapnic episodes in 30 critically ill patients who were being weaned from mechanical ventilation. Clinically significant hypercapnic episodes were detected by increments of >mmHg in end-tidal co2with a sensitivity of 82%, a specificity of 76%, and a negative predictive value of 94%.SourceSaura P et al. Use of capnography to detect hypercapnic episodes during weaning from mechanical ventilation. Intensive Care Med 1996;22:374–81.

ISSN:1068-0640    

出版商:OVID    

年代:1996

数据来源: OVID