Exercise testing prior to lung resection has long and honored tradition. It began as a test of tolerance using simple techniques such as stair climbing. This was followed by aggressive and invasive protocols using right cardiac catheterization in the search for pulmonary hypertension. More recently, measurement of VO2 with exercise has been reported to predict both postoperative mortality and survivable morbidity. Exercise testing holds promise as a noninvasive test to predict the physiologic outcome from lung resection. Significant questions remain concerning the pathophysiologic mechanisms responsible for an abnormal result and who should be denied thoracotomy based on these results.

Evaluation of diseases in the chest by MR is continually evolving. Early studies showed the potential of the technique for imaging the mediastinal and hilar structures and for demonstrating the normal anatomy of the thorax on sagittal, coronal, and transverse MR images. As more data have been compiled, investigators have compared MR to computed tomography for its ability to assess mediastinal and hilar adenopathy and masses, bronchogenic carcinoma and other pulmonary parenchyma lesions, and for assessment of the pulmonary vascularity. MR has been shown in these situations generally to provide equivalent information to that provided by computed tomography. MR, compared to computed tomography, is still in its infancy in regard to the length of time of its availability and in relation to the MR technology for obtaining images. MR is a technique that has wide variation as to type of image quality obtained depending upon the MR system utilized and the pulse sequence utilized. Because of the diverse nature of potential variables for imaging, many times the images are not equal in quality. As a consequence of this significant variability, the data in the literature are divergent on the precise utility of MR. Although the recommended use of MR may change rapidly, the current feeling is that MR should be used as a procedure complementary to computed tomography in those patients with allergy to iodinated contrast material and to aid in defining equivocal lesions as seen on computed tomography, such as small central hilar bronchogenic carcinomas.

Previous reports of pulmonary rehabilitation programs have demonstrated improvement in exercise capacity in subjects with disabling pulmonary disease. However, the cost-effectiveness, benefits to outpatients in a community setting, durability of these improvements, and mechanism of improved exercise capacity remain unclear. Forty-four patients with an average FEV1 of 33 +/- 4 percent of predicted completed a six-week long period of supervised treadmill exercise, as well as a continuing home program. Twenty percent had previously unsuspected cardiac disease discovered through the program, while 36 percent had previously unsuspected exercise desaturation. Cardiopulmonary stress testing before and after the program revealed a 73 +/- 16 percent improvement in aerobic capacity (METs peak [power]) and a 250 +/- 78 percent improvement in endurance (MET-min [work]). No significant change was seen in VE max, HR max, FEV1, or the degree of exercise desaturation. Only a small improvement was noted in VO2 max (15 +/- 8 percent) and O2 pulse (16 +/- 8 percent), suggesting that most of the improvement was due to improved muscle efficiency. Follow-up testing at 12 +/- 3 months in 24 subjects revealed that 89 +/- 7 percent of the peak exercise performance was maintained. The cost of the basic program was +800. The results demonstrated that an outpatient community hospital pulmonary rehabilitation program can accomplish substantial exercise capacity improvement with sustained benefits in a cost-effective manner.

A prospective, double-blind, randomized study of the role of corticosteroids in the treatment of tuberculous pleurisy was performed in 40 patients. All patients received adequate antituberculosis chemotherapy (isoniazid, 300 mg/day; rifampin, 450 mg/day; ethambutol, 20 mg/kg/day) for more than nine months. They were randomly assigned to take prednisolone 0.75 mg/kg/day orally or placebo for the initial treatment, which was tapered gradually for the next two to three months. Twenty-one were treated with steroids and 19 were given a placebo. The two groups were identical with regard to age, sex, duration from onset of symptoms to diagnosis, and initial amount of pleural effusion. The mean duration from symptoms (fever, chest pain, dyspnea) to relief was 2.4 days in the steroid-treated group, and 9.2 days in the placebo group (p less than 0.05). Complete reabsorption of pleural effusion occurred an average of 54.5 days in the steroid-treated group and 123.2 days in the placebo group (p less than 0.01). The development of residual pleural thickening was not influenced by the administration of corticosteroids. No serious side effects were noted during the treatment in either group. We conclude that the administration of corticosteroids, in conjunction with antituberculosis chemotherapy, will resolve the clinical symptoms more quickly and hasten the absorption of pleural effusion in patients with tuberculous pleurisy.

This report describes three cases of massive mobile right heart thrombus and reviews the available literature to better define the pathophysiology, natural history and most appropriate therapy of the syndrome. The clinical presentation of most patients has been severe cardiopulmonary dysfunction and the diagnosis has been made by echocardiographic study. The most likely source of these cardiac thrombi is the large systemic veins. The associated mortality risk is very high. Therapy has, heretofore, been individualized. Embolectomy has been most favored, with a survival rate of 80 percent. The role of thrombolytic therapy remains to be delineated. Therapy should, however, be initiated rapidly because of the precipitous nature of the mortality risk.

A stratified random sample of a large state (Michigan) was studied by respiratory questionnaire, medical history, and physical examination. Data were obtained on 1,169 white adults. The prevalence of chronic bronchitis and chronic wheezing varied with sex (greater in men) and smoking history (greatest in current smokers). The prevalence of chronic bronchitis varied depending on whether it was (1) defined simply as chronic production of sputum, (2) diagnosed by the examining physician, or (3) previously diagnosed by a physician. Dyspnea was more common in women; in men, it was least common in nonsmokers but was of similar prevalence in ex-smokers and current smokers. Angina was more commonly reported by women, but previously diagnosed heart attack was consistently more common in men. Wheezing was by far the most common physical sign, present in 5.1 percent of the total population and 9.2 percent of male current smokers. Clubbing and rales were each noted in 1.2 percent of the total population. The prevalences of clinical findings in this cross section of a large state should be useful for comparison with other populations.

We reviewed the literature evaluating pediatric asthma education interventions to assess their impact on morbidity (school absences and health care utilization). Thirteen studies were analyzed, most of which reported favorable outcomes. Of the ten studies reporting on school absences, only seven used tests of statistical significance when reporting on postintervention reductions, and of those, only two found a significant decrease in absenteeism. Similarly, among the studies reporting on utilization, not all used tests of statistical significance when reporting on postintervention decreases in physician visits, ER visits, and hospitalization. Only four of the ten studies used adequate sample sizes to detect a 20 percent reduction in school absences, and stratification of the sample by severity of asthma suggests that some programs do reduce health care utilization among those children with more severe disease. We conclude that the effectiveness of asthma educational programs on reducing school absences and health care utilization may be small. These programs are best directed toward children with moderate or severe disease. Finally, it is important for pediatricians, children with asthma, and their families to have realistic expectations about what these programs may accomplish.

A report of pulmonary edema following acute upper airway obstruction in an adult is presented, and the literature involving 25 additional cases is reviewed. This form of pulmonary edema appears to be related to markedly negative intrathoracic pressure due to forced inspiration against a closed upper airway resulting in transudation of fluid from pulmonary capillaries to the interstitium. Postanesthetic laryngospasm is the most common cause of pulmonary edema in adults (11/26 cases). The edema usually clears rapidly with supportive care. Aggressive diagnostic and therapeutic interventions may be avoided if the syndrome is recognized. Maintenance of oxygenation and a patent airway are the mainstays of treatment.

A 15 1/2-year-old boy died suddenly while swimming. He had a family history of sudden death involving three consecutive generations, including a brother. The patient had a history of exercise-related syncope, for which he was being treated with nadolol. Autopsy showed enlarged heart, normal coronary arteries, right ventricular septal hypertrophy, quadricuspid pulmonary valve, accessory tricuspid valve, and a moderately elongated and thickened mitral valve. Conduction system revealed that the penetrating bundle was pushed to the left side of the summit of the ventricular septum by the right ventricular septal hypertrophy; it was lobulated and showed fatty-fibrous changes. These findings extended throughout the beginning of the bundle branches. We conclude that in this patient with familial sudden death and normal QT interval, the abnormal right ventricular septal hypertrophy altered the course and produced degenerative changes in the conduction system, which may have caused sudden death.

Pyrazinamide is an antituberculosis drug synthesized in the 1950s and formerly used only as salvage therapy. Recent developments have elevated it to a central role in tuberculosis chemotherapy as the essential addition to isoniazid and rifampin which makes it possible to successfully complete treatment in six months. This is accomplished with no increase in hepatotoxicity. The only substantial side effect of this drug given at the dosage and for the duration used in these six-month regimens is a polyarthralgia which is only bothersome and not sufficient to warrant interruption of therapy. More rarely, acute gout is produced. The early history and pharmacology of this now first line antituberculosis drug are reviewed herein.

Patients with cystic fibrosis (CF) show abnormal aminoglycoside pharmacokinetics. After a conventional dose, the serum concentrations in CF patients are lower than those in nonCF patients. The lower serum concentrations in CF might be explained by increased total body clearance and/or a larger volume of distribution. The therapeutic range of aminoglycosides is narrow due to oto- and nephrotoxicity. The changed pharmacokinetics and the narrow therapeutic range make it difficult to ensure that patients with CF are adequately and safely treated with aminoglycosides. The mode of administration of aminoglycosides influences the antibacterial effect of these agents on Pseudomonas aeruginosa and the development of possible side effects. The therapeutic implications of these facts are discussed.