Pulmonary complications of cancer treatment.

Great strides have been made in the treatment of cancer. This success, however, has not come without a price. Pulmonary complications of cancer treatment have proven to be common and often result in significant morbidity. The manifestations of such complications may range from an asymptomatic patient with an abnormal chest, radiograph to one with transient dyspnea to varying degrees of chronic pulmonary insufficiency to an acute lethal event. Each of the major treatment modalities, surgery, radiation therapy, and chemotherapy, carries a significant complication rate that often limits its effectiveness. When two or more modalities are used concurrently or sequentially, the risk of complications increases further. The respiratory system, for a number of reasons, has proven to be especially vulnerable to treatment-related complications.

Delayed tension pneumothorax after laparoscopy.

Laparoscopy is a safe and useful procedure in evaluating intraabdominal disease. Serious complications have been reported but are rare. Laparoscopy related pneumothorax is one such complication that may occur during the procedure or in the immediate period thereafter. This complication is typically neither hemodynamically significant nor tension in nature. We report the unique case of a 52-year-old woman who not only developed acute respiratory compromise from a tension pneumothorax but did so 3 h after the completion of a seemingly uneventful laparoscopic procedure. Prompt recognition of this potential complication may permit immediate and effective treatment of this life-threatening complication.

Reactive airways dysfunction syndrome.

Two types of occupational asthma have been identified and are distinguished by whether they appear after a latency period. Asthma without a latency period is best illustrated by irritant-induced asthma. The reactive airways dysfunction syndrome is a subset of irritant-induced asthma. Although case reports appeared in the literature before 1985, the term reactive airways dysfunction syndrome was coined in 1985. Since that report a number of case reports of asthma-like illnesses developing as the direct consequence of massive toxic inhalation exposure have been published. Not all experts, however, are certain that reactive airways dysfunction syndrome is a real and distinct clinical entity. Most studies and reviews, although acknowledging the current gap in our knowledge of the epidemiology, pathogenesis, and pathologic findings, conclude that the available scientific evidence supports the conclusion that reactive airways dysfunction syndrome and irritant-induced asthma are valid disorders.

Occupational asthma. Serious consequences for workers and employers.

Patients affected by occupational asthma have respiratory symptoms that may persist for months, years, or even life. Hundreds of substances have been implicated in the disease, and the list is expected to grow. The authors discuss management of this sometimes life-threatening condition and emphasize the importance of environmental controls to prevent future cases.

The FEF25-75% and the clinical diagnosis of asthma.

Nonspecific bronchial provocation testing is clinically useful in the evaluation of patients with symptoms suggestive of asthma. Testing is usually reserved for those with normal or near normal baseline spirometry. Although bronchial provocation testing is safe and widely available, the protocol is time consuming and not without expense. It has been reported that a reduced FEF25-75% in the context of an otherwise normal spirogram suggests that asthma should be considered. To evaluate this suggestion, we compared the baseline FEF25-75% (expressed as percent of predicted) with the results of the subsequent methacholine bronchial provocation test in 205 consecutive patients referred for testing. The mean baseline FEF25-75% in the 112 patients with normally responsive airways (ie, a negative bronchial provocation test) was 95.4 +/- 27.5%. In the 93 patients with a positive bronchial provocation test, the mean FEF25-75% was 77.6 +/- 27.2%. The mean FEF25-75% in those with hyperresponsive airways was significantly lower (t = 4.616, P < .0001). Of those patients with a positive bronchial provocation test, there was no significant correlation, however, between the baseline FEF25-75% and the degree of bronchial hyperresponsiveness as assessed by the PC20FEV1 (r = .154, P = .141). When a significant reduction in FEF25-75% was defined as less than 60% of predicted, the sensitivity of the prediction rule was 25.8%, the specificity was 92.0%, the positive predictive value was 72.7%, and the negative predictive value was 60.0%. From these results, we conclude that the FEF25-75% derived from simple spirometry may be useful in predicting the presence or absence, but not the degree, of bronchial hyperresponsiveness.

Case report: Castleman disease in association with POEMS.

Castleman disease, or angiofollicular lymph node hyperplasia, and POEMS (Polyneuropathy, Organomegaly, Endocrinopathy, Monoclonal gammopathy, and Skin changes), are associated and can lead to a clinical conundrum. The physician caring for a patient with Castleman disease should be alert to the development of multiple endocrine deficiencies, including primary hypogonadism, diabetes mellitus, hypothyroidism, and adrenal insufficiency. Avoidance of treating hypothyroidism alone when there is concomitant subclinical adrenal insufficiency is important, to avoid precipitating an adrenal crisis. A better outcome may result from earlier recognition of the endocrinopathies of this syndrome. This article describes a patient with Castleman disease in whom the features of POEMS unfolded over the ensuing years.

Bronchodilator testing "confidence intervals" based on the level of bronchial responsiveness.

"Confidence intervals" based upon inhalation of placebo have been proposed as criteria for defining a significant response to an inhaled bronchodilator. The published intervals were derived from a clinically heterogeneous population. We calculated the difference (delta) between spirometric data before and after placebo in 109 consecutive patients referred for methacholine bronchoprovocation challenge testing. The mean delta, expressed both as a percent change and as actual volume change for both the FVC and FEV1, was not significantly different in patients with bronchial hyperresponsiveness, as compared to subjects with a negative methacholine challenge test; however, the variance of measurements in hyperresponsive subjects was significantly greater than that of the normal population. In addition, as the category of responsiveness increased from mild to moderate to severe hyperresponsiveness, so did the variance within these groups. A negative correlation between the measured PC20FEV1 and the volume and percent change was noted. We conclude that patients with hyperresponsive airways may display increased spirometric variation before and after placebo. This general approach for establishing normal limits for defining a significant response appears to be valid, but the actual values used may vary, depending on the composition of the population tested and the goals of the study. Also, the use of the term, "confidence intervals," in this context is inappropriate; and we propose, instead, the use of percentiles and the simpler terms, upper 90th or 95th percentiles.

Advances in occupational asthma.

Clinical and research interests in occupational asthma increased dramatically in the 1980s. Advances in our knowledge base have led to improved recognition, management, and methods for preventing this disorder. An accelerated pace of basic and clinical research is anticipated in the 1990s. These efforts will likely lead to a more complete understanding of the disease (and pay dividends in understanding asthma itself). Occupational asthma is predicted to be the preeminent occupational lung disease in the next decade.

Hepatic hydrothorax. Cause and management.

Significant pleural effusions are infrequently noted in patients with cirrhosis of the liver. A large effusion (hepatic hydrothorax) occasionally appears during the course of the disease. The fluid in the pleural space is believed to be derived from ascitic fluid that may accompany hepatic cirrhosis. Although the exact mechanism is somewhat controversial, it appears that the ascitic fluid is transported directly into the pleural space. A therapeutic thoracentesis, usually accompanied by a paracentesis, may be necessary to relieve acute symptoms. Long-term management, however, centers around eliminating or reducing the formation of ascites. When this is not successful, tube thoracostomy followed by chemical pleurodesis, primary repair of diaphragmatic defects with pleural sclerosis, or peritoneovenous shunting in conjunction with chemical pleurodesis may be attempted. These interventions may or may not be successful. Management of hepatic hydrothorax remains a clinical challenge.