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Articles

Chest. 1991;100(6):1481-1482. doi:10.1378/chest.100.6.1481
Abstract
Topics: asthma
Chest. 1991;100(6):1482-1483. doi:10.1378/chest.100.6.1482
Abstract
Topics: dust , vermont
Chest. 1991;100(6):1483-1484. doi:10.1378/chest.100.6.1483
Abstract
Chest. 1991;100(6):1484-1486. doi:10.1378/chest.100.6.1484
Abstract
Topics: nicotine
Chest. 1991;100(6):1486. doi:10.1378/chest.100.6.1486
Abstract
Chest. 1991;100(6):1488-1492. doi:10.1378/chest.100.6.1488

The prime complication of heparin therapy is bleeding, and the gastrointestinal tract is the most common site of bleeding in patients treated with heparin. We recently reported that gastroduodenal lesions are common in patients admitted because of acute venous thromboembolism, and now we present our experience in a larger series of patients. The aims of the study were to try to validate our previous findings and to identify clinical factors that could increase the likelihood of having an acute, potential bleeding lesion in the gastroduodenal tract. Upper gastrointestinal endoscopy was performed on admission in 155 consecutive patients with acute venous thromboembolism (118 with deep vein thrombosis, 37 with pulmonary embolism). Acute lesions (both peptic ulcers and diffuse erosions) were found in 19 of 118 patients (16 percent) with venous thrombosis, and in 14 of 37 patients (38 percent) with pulmonary embolism (p = 0.005). When only patients with pulmonary embolism were considered, lesions were more commonly found in men, and in patients with severe hypoxemia on admission. When considered overall, only the timing of endoscopy was statistically significant; acute lesions were more commonly found when endoscopy was performed early after admission. No significant differences were found in terms of age, sex, smoking habits, alcohol intake, concomitant drug ingestion, comorbid diseases, or previous history of ulcer. The very high incidence of upper GI tract lesions in these patients will have long-term diagnostic/therapeutic implications which cannot be ignored. Who should receive prophylactic H2 blockers and for how long remains to be determined.

Chest. 1991;100(6):1493-1496. doi:10.1378/chest.100.6.1493

We have previously reported that patients with deep vein thrombosis (DVT) and scintigraphic evidence of pulmonary embolism (PE) had a fall in platelet count, as compared with their levels before thrombosis had developed. Otherwise, no changes were found in DVT patients without embolism. We recently conducted a prospective study with a larger series of patients and studied platelet count behavior in 189 consecutive patients with acute venous thromboembolism (VTE) in whom a baseline blood cell count was available (obtained before thromboembolism developed). We found no significant differences in baseline platelet counts between groups. However, at the time of VTE diagnosis the analysis of variance demonstrated that mean platelet count was significantly higher in patients without embolism as compared with PE patients (p less than 0.001). On the other hand, no differences were found between patients with silent PE and those with clinically obvious PE. When patients with postoperative VTE and those with nonpostoperative VTE were analyzed separately, mean platelet count increased only in postoperative DVT patients without embolism (p less than 0.001). In the absence of a previous intervention, DVT did not produce any change in platelet count, while PE significantly reduced platelet number (p less than 0.008). In DVT patients without respiratory symptoms of embolism, we suggest that a lung scan should be performed when platelet count is lower than baseline value. For patients with a higher count, the probability of finding PE is very low, and scintigraphy is not cost-effective.

Chest. 1991;100(6):1497-1502. doi:10.1378/chest.100.6.1497

The efficacy and safety of oral temafloxacin (600 mg) and ciprofloxacin (500 mg) twice daily for seven days were compared in patients with mild to moderate lower respiratory tract infections. Fifty-eight of 64 (91 percent) patients who received temafloxacin and 63 of 67 (94 percent) patients who received ciprofloxacin had clinical cure or improvement; bacteriologic cure occurred in 61 (95 percent) and 63 (94 percent), respectively. All 14 patients with pneumonia were clinically cured or improved and bacteriologically cured; 11 had complete resolution of roentgenographic evidence of pneumonia. Both quinolones eradicated most major respiratory pathogens. In the ciprofloxacin group, organisms persisted in three of seven Pseudomonas aeruginosa isolates and in one of eight Hemophilus parainfluenzae isolates; all these pathogens were eliminated with temafloxacin. Theophylline blood levels significantly increased by 25 percent in the ciprofloxacin group and decreased by 5 percent in the temafloxacin group. Adverse events, mostly dizziness, headache, and gastrointestinal effects, occurred in 43 percent of temafloxacin patients and in 31 percent of ciprofloxacin patients.

Chest. 1991;100(6):1503-1506. doi:10.1378/chest.100.6.1503

Clarithromycin, a new macrolide antibiotic, is at least four times more active in vitro than erythromycin against Legionella pneumophila. In this study the safety and efficacy of orally administered clarithromycin (500 to 1,000 mg bid) in the treatment of Legionella pneumonia were evaluated. Forty-six patients were enrolled in the study, 15 of whom had not responded to previous routine anti-Legionella therapy (erythromycin, ofloxacin, rifampin [rifampicin], or tetracycline). Twelve patients prematurely discontinued the study (nine by the patient's request while feeling well; one because of cancer diagnosis; and two because of adverse events). The response rates after treatment were as follows: clinical cure rate, 98 percent (43/44); clinical success (cure or improved), 100 percent (44/44); radiographic success (cure and improved), 93 percent (28/30); direct antigen fluorescence resolution, 100 percent (40/40); and bacteriologic cure, 100 percent (13/13). Ten patients reported 13 adverse events (seven mild, four moderate, and two severe). Clarithromycin is a safe effective treatment for patients with severe chest infections due to Legionella pneumophila.

Chest. 1991;100(6):1507-1514. doi:10.1378/chest.100.6.1507

The issue of whether low levels of granite dust exposure lead to radiographic abnormalities after a lifetime of exposure has not been settled. In 1983, we carried out a radiographic survey of the Vermont granite industry, consisting of quarry and stone shed workers who had been exposed to the low dust levels prevailing in the industry since 1938 to 1940. Films were read by three "B" readers, using the ILO classification system, which requires the identification of both rounded and irregular opacities, as well as combinations of both. X-ray films were taken of 972 workers, out of a total work force of approximately 1,400. Of these films, 28 (3 percent) were interpreted by either two or three of the three readers as showing abnormalities consistent with pneumoconiosis. Only seven films (or 0.7 percent of the entire cohort) showed nodular or rounded opacities of the type typically seen in uncomplicated silicosis. The remainder of the abnormal x-ray films showed irregular opacities, largely in the lower lung zones, which are of uncertain significance, but may be related to heavy cigarette smoking and aging, and possibly dust inhalation. In addition, total gravimetric dust concentrations in the workplace were measured; 417 respirable-size mass samples showed concentrations of 601 micrograms/cu m +/- 368 micrograms/cu m. Using previously published estimates of 10 percent quartz in granite dust, the average quartz concentration was 60 micrograms/cu m. Twelve percent of the samples exceeded 100 micrograms/cu m, the current OSHA standard for quartz. We conclude that control of quartz exposure in the Vermont granite industry to levels which are on average less than the current OSHA standard has essentially eliminated definite radiographic changes of silicosis. The significance of the irregular opacities in the lower lung zones seen on a majority of the 28 x-ray films judged to be abnormal is not clear.

Topics: dust , vermont
Chest. 1991;100(6):1515-1521. doi:10.1378/chest.100.6.1515

The purpose of this study was to identify the strengths and limitations of using portable peak flowmeters to document suspected cases of occupational asthma that were reported to a statewide surveillance project. The New Jersey Department of Health conducts surveillance for occupational asthma as part of the federally sponsored Sentinel Event Notification System for Occupational Risks (SENSOR). Between May 1988 and January 1990, 70 cases were reported voluntarily by physicians. Subjects who were still employed in suspected work sites were requested to test themselves for at least 15 days, using portable peak flowmeters to generate serial measurements of their peak expiratory flow rate (PEFR). For each of the 14 subjects who were successfully tested, the PEFR data provided valuable information about their asthma-work association. However, a large number of subjects whose cases were reported (56) either could not be tested or were not successfully tested. The proportion of subjects completing the test would probably improve if it were conducted when their conditions were first diagnosed. Accordingly, the collection of serial peak flow measurements to document occupational asthma would best be initiated by the treating physician when the patient first sought care, rather than waiting until after the case was reported to the state health department.

Chest. 1991;100(6):1522-1527. doi:10.1378/chest.100.6.1522

Long-term oxygen is the only therapy that has been shown to improve survival in patients with chronic obstructive pulmonary disease. The aim of this study was to assess the predictors of survival in such patients treated with long-term oxygen therapy. We studied 179 patients who were assessed for long-term oxygen therapy in two Departments of Respiratory Medicine: in Warsaw and in Edinburgh. Those who died following the prescription of long-term oxygen therapy had a similar forced expiratory volume in the first second (FEV1) and arterial carbon dioxide tension, but a slightly lower arterial oxygen tensions (p less than 0.05) than those who survived (p less than 0.05). A small but significant fall in FEV1 and a rise in arterial carbon dioxide tension (p less than 0.05) occurred in both survivors and nonsurvivors after treatment with oxygen, but arterial oxygen tension breathing air continued to fall only in those who died (p less than 0.005). Only two variables were independent predictors of survival in patients with chronic obstructive pulmonary disease treated with long-term oxygen therapy. These were the arterial oxygen tension and the mean pulmonary arterial pressure (Ppa). However, when the calculation was made on patients with PaO2 less than or equal to 60 mm Hg (n = 154), then FEV1 and PaO2 but not Ppa were found to predict survival.

Chest. 1991;100(6):1528-1535. doi:10.1378/chest.100.6.1528

Between December 1985 and August 1988, there were 115 patients at 13 centers who were entered on a randomized comparison of tetracycline and bleomycin for treatment of malignant pleural effusions. Fifteen patients were not treated, primarily due to rapid progression of systemic cancer. Fifteen patients entered on a high-dose regimen of bleomycin (120 units) were excluded from this analysis (following early closure of that arm), leaving 85 patients randomized to low-dose bleomycin (60 units; 44 patients) or tetracycline (1 g; 41 patients). Patients were required to have a cytologically positive pleural effusion, good performance status (0, 1, or 2), lung reexpansion following tube thoracostomy with drainage rates of 100 ml/24 or less, no prior intrapleural therapy, no prior systemic bleomycin therapy, no chest irradiation, and no recent (four weeks) change in systemic therapy. A total of 11 patients (five with bleomycin and six with tetracycline) were not evaluable due to technical problems with tube drainage (one), loss to follow-up (two), sudden death due to pulmonary embolus (one), and rapid progression of systemic disease (seven). There were no clinically significant differences in demographic factors, primary site, performance status, or presence of metastases other than pleural effusion. Overall survival did not differ between the two groups. Median time to recurrence or progression of the effusion was 32 days for tetracycline-treated patients and at least 46 days for bleomycin-treated patients (p = 0.037). The recurrence rate within 30 days of instillation was 36 percent (10/28) with bleomycin and 67 percent (18/27) with tetracycline (p = 0.023) (not all patients were restudied in the first 30 days). By 90 days the corresponding recurrence rates were 30 percent (11/37) for bleomycin and 53 percent (19/36) for tetracycline (p = 0.047). Toxicity was similar between groups.

Chest. 1991;100(6):1536-1541. doi:10.1378/chest.100.6.1536

The aim of the study was to evaluate if D-dimer and thrombin-antithrombin III complex determinations in patients with clinically suspected pulmonary embolism create a discrimination between patients to be further investigated with lung scanning and those who should be investigated for other diseases mimicking pulmonary embolism. The Data-Fi Dimertest Latex Assay, MAbCO Dimertest EIA, and TAT EIA were performed in 100 consecutive patients (26 percent outpatients) who were sent to our institution for lung scanning by their attending physicians because of clinically suspected pulmonary embolism. The D-dimer Latex Assay was positive (greater than 500 ng/ml) in 12 (48.0 percent) of 25 patients with high probability of pulmonary embolism and in one (11.1 percent) of nine with intermediate probability, respectively. Only one patient (1.5 percent) with a normal scan had a positive latex assay, presumably due to inapparent bleeding after a computed tomographic (CT)-guided liver biopsy. Referring to 120 ng/ml as upper limit of normal (mean +/- 2 SD of healthy controls), the D-dimer enzyme immunoassay (EIA) was positive in 21 (84.0 percent) of 25 patients with high probability, in six (66.7 percent) of nine patients with intermediate probability, and in 40 (60.6 percent) of 66 patients with normal/low probability of pulmonary embolism, respectively. The TAT EIA was positive (greater than mean +/- 2 SD of healthy controls = 3.53 ng/ml) in 18 (72.0 percent) of 25 patients with high probability, in five (55.6 percent) of nine patients with intermediate probability and in 16 (24.2 percent) of 66 patients with normal/low probability of pulmonary embolism. A normal result in one of these hemostaseologic tests did not predict a low probability of pulmonary embolism after lung scanning. Thus, it is not justified to exclude patients with clinically suspected pulmonary embolism from further investigation by lung scanning because of a normal result in one of these tests.

Chest. 1991;100(6):1542-1548. doi:10.1378/chest.100.6.1542

To determine the effects of intermittent hypoxemia on daytime sleepiness in the clinical setting of obstructive sleep apnea syndrome, we enrolled seven patients in a prospective, randomized, crossover study. We had two experimental conditions with NCPAP treatment as follow: (1) to correct apneas, sleep fragmentation, and hypoxemia; and (2) to correct apneas and sleep fragmentation and at the same time, induce intermittent hypoxemia. The outcome variable, daytime sleepiness, was measured objectively with the multiple sleep latency test following completion of baseline and each treatment condition. Compared with sleep latencies in the untreated condition, both experimental treatment arms prolonged sleep latencies (p less than 0.05). We found no statistically significant differences between mean MSLT scores obtained after NCPAP treatment under hypoxemic and nonhypoxemic conditions. In summary, two nights of intermittent nocturnal hypoxemia during NCPAP treatment for OSAS did not diminish the objective improvement in daytime somnolence seen with NCPAP treatment in the absence of nocturnal hypoxemia. Results lend further support to the hypothesis relating excessive daytime sleepiness to sleep fragmentation.

Chest. 1991;100(6):1549-1552. doi:10.1378/chest.100.6.1549

The aim of the study was to assess the effect of absence of atrial contraction during exercise. During the incremental ergometer exercise tests, heart rate, oxygen uptake, and oxygen pulse in patients with isolated atrial fibrillation were compared with those in control subjects at rest, at the exercise level of gas exchange anaerobic threshold, and at peak exercise. The study population consisted of 51 subjects aged 40 years or more: 12 patients with isolated atrial fibrillation and 39 control subjects with normal sinus rhythm. Heart rate in control subjects was lower than that in patients with isolated atrial fibrillation, at rest, anaerobic threshold, and peak exercise (74 +/- 12 vs 85 +/- 8 beats/min at rest, 108 +/- 16 vs 134 +/- 18 beats/min at anaerobic threshold, and 151 +/- 16 vs 173 +/- 22 beats/min at peak exercise, all p less than 0.01). During exercise, oxygen uptake in patients with isolated atrial fibrillation was not significantly different from that in control subjects. Oxygen pulse in patients with isolated atrial fibrillation was lower than that in control subjects during exercise (6.45 +/- 2.04 vs 7.84 +/- 1.63 ml/beat at anaerobic threshold, 7.79 +/- 2.28 vs 9.16 +/- 1.79 ml/beat at peak exercise, both p less than 0.05). In patients with isolated atrial fibrillation, the oxygen pulse might be reduced due to the lack of atrial contraction during exercise. However, the oxygen uptake that represents the exercise capacity would be preserved with the increase in heart rate.

Chest. 1991;100(6):1553-1557. doi:10.1378/chest.100.6.1553

Retrospectively, we reviewed the charts of 101 patients at the University of Kansas Medical Center who received low-intensity anticoagulation for mechanical prosthetic valves implanted over a 17-yr period. The mean duration of follow-up was 4.6 yr, and the total duration of follow-up was 466.5 patient-yr. The patients' records were evaluated for evidence of hemorrhagic or thromboembolic complications. A prothrombin time ratio of 1.3 to 1.5 times control was considered to be low-intensity anticoagulation. There were three thromboembolic events or 2.9/100 patient-yr of follow-up at a prothrombin time ratio of less than 1.3, four thromboembolic events or 2.5/100 patient-yr of follow-up at 1.3 to 1.5 times control, four thromboembolic events or 2.2/100 patient-yr of follow-up at 1.6 to 2.0 times control, and no thromboembolic events at prothrombin time ratios greater than 2.0 times control. Hemorrhagic events occurred in three patients at a prothrombin time ratio of less than 1.3 times control or 2.8/100 patient-yr of follow-up, in six patients at 1.3 to 1.5 times control or 3.8/100 patient-yr of follow-up, in ten patients at 1.6 to 2.0 times control or 5.5/100 patient-yr of followup, and in two patients at 2.1 to 2.5 times control or 12.2/100 patient-yr of follow-up. The rate of hemorrhagic events at 2.5 times control was 470/100 patient-yr follow-up. While not providing definitive proof, we believe that our retrospective study provides supportive evidence for the use of low-intensity anticoagulation in patients with mechanical cardiac prostheses.

Chest. 1991;100(6):1558-1561. doi:10.1378/chest.100.6.1558

We evaluated the safety of enalapril administration in 20 very old (76 +/- 7 years) patients with rapidly progressive congestive heart failure (deteriorating from New York Heart Association class 2 to class 4 on admission). They were all given increasing doses of enalapril regardless of concomitant diuretic therapy and state of hydration. Renal function deteriorated in four patients (group A) and remained unchanged in 16 (group B). The mean pretreatment serum creatinine level in group A was significantly higher than that in group B (2.4 vs 1.3 mg/dl, p less than 0.001). No patient with a serum creatinine level less than 1.9 mg/dl on admission had further impairment of renal function. Groups A and B did not differ by age, concomitant diseases (including hypertension and diabetes mellitus), or medications (including diuretics) or by in-hospital serum electrolyte concentrations and blood pressure. Renal damage was noted during the initial four days of the study and was reversible following discontinuation of enalapril. Our data suggest that enalapril can be safely administered to very old patients with rapidly progressive congestive heart failure provided that the initial serum creatinine level is below 1.9 mg/dl. In patients with a higher serum creatinine level, careful monitoring and prompt discontinuation of enalapril administration can prevent irreversible renal damage.

Chest. 1991;100(6):1562-1566. doi:10.1378/chest.100.6.1562

Twenty-one of 146 cases of spontaneous pneumothorax that were treated by thoracentesis or continuous low negative pressure suction drainage (-12 cm H2O) of the pleural space developed REPE. The rate of REPE was higher in patients 20 to 39 years of age than in those over the age of 40, and the rate progressively increased in proportion to the extent of pneumothorax, as assessed by roentgenographic criteria. It is postulated that age-related changes in the lung may afford some degree of protection against developing REPE. It is also suggested that the treatment of pneumothorax with thoracentesis and/or suction drainage in young patients, or in the face of a large pneumothorax, requires careful consideration in view of a relatively high incidence of REPE in such individuals.

Topics: pulmonary edema
Chest. 1991;100(6):1567-1571. doi:10.1378/chest.100.6.1567

The CD11/CD18 leukocyte surface adhesion glycoprotein family consists of three different heterodimeric molecules that play an essential role in adhesion-related functions such as migration, chemotaxis, and phagocytosis. This suggests an important role of these molecules in inflammatory processes. The three molecules consist of a specific alpha chain (CD11a, CD11b, or CD11c) and share a common beta chain (CD18). The expression of the cell adhesion glycoprotein family on alveolar macrophages (AM) and peripheral blood monocytes (PBM) was studied in bronchoalveolar lavage (BAL) fluid samples and PB from 11 smokers and 10 nonsmoking healthy volunteers. Smokers showed increased numbers of macrophages in their BAL fluid as compared with nonsmokers. This is probably due to an increased recruitment of blood monocytes to the alveoli, since the numbers as well as percentages of cells with a monocyte-like morphology were significantly increased in BAL fluid samples from smokers. The proportion of CD11+/CD18+ AM in the BAL fluid from smokers, however, was decreased as compared with AM from nonsmokers and PBM. This suggests that tobacco smoke might play a role in the downregulation of these leukocyte adhesion glycoproteins on AM.

Chest. 1991;100(6):1572-1577. doi:10.1378/chest.100.6.1572

An experimental technique designed to predict theophylline doses needed to attain therapeutic theophylline concentrations in 43 emergency department (ED) patients was compared with a standard conventional regimen in 46 ED patients. The experimental protocol utilized a computer-assisted dosage prediction program that incorporated baseline theophylline concentration rapidly obtained using a bedside assay. The standard protocol used conventional loading and infusion rates, as well as an estimate of time of last theophylline dose based on patient history. Plasma theophylline concentrations, estimated 1 and 6 hours after commencement of aminophylline therapy in each regimen, were compared. The experimental protocol was equally rapid but much more accurate in achieving targeted theophylline concentrations. Experimental dosage prediction was associated with a higher proportion of theophylline concentrations in the therapeutic range at 1 (81 percent vs 26 percent; p less than 0.001) and 6 hours (91 percent vs 37 percent; p less than 0.001). There was a trend toward fewer toxic concentrations recorded at 1 (0 percent vs 7 percent; p = 0.27) and 6 hours (0 percent vs 10 percent; p = 0.08). This protocol, which was performed quickly and without difficulty by residents in a busy hospital ED, offers an opportunity to improve the efficacy and decrease the toxicity of theophylline use in asthma emergencies.

Chest. 1991;100(6):1578-1581. doi:10.1378/chest.100.6.1578

The principal features of computed tomography in hydatid disease of the lungs were reviewed in ten patients with surgically verified hydatid disease of the lungs. On the basis of localization and multiplicity, hydatid cysts of the lungs can be classified in three distinct categories: single unilateral unilocular cysts with or without daughter cysts, unilateral multiple cysts with or without daughter cysts, and bilateral multiple cysts. Cystobronchial communication may lead to cavitary lesions, while infection of the cyst may alter the attenuation values and produce a solid appearance. On the basis of density and clinical symptoms, hydatid cysts of the lungs can be classified as simple cysts, complicated cysts, and ruptured cysts, including cystobronchial communication.

Topics: lung , echinococcosis
Chest. 1991;100(6):1582-1585. doi:10.1378/chest.100.6.1582

With a few simple modifications, an aerosol mask was adapted to deliver high concentrations of oxygen. We compared the delivery of high concentrations of oxygen by this modified aerosol mask (MAM) with that of a nonrebreathing mask (NRM) in five normal volunteers and six patients with respiratory failure. Besides improved oxygenation, the MAM also permitted the following: humidification of the inspired oxygen, nebulization of bronchodilators, oropharyngeal suctioning, and performance of fiberoptic bronchoscopy. In lieu of intubation and mechanical ventilation, MAM may be a better alternative to a NRM for maintaining adequate oxygenation until the clinical situation improves.

Chest. 1991;100(6):1586-1591. doi:10.1378/chest.100.6.1586

Two recent epidemiologic case-control studies suggested that fenoterol, a selective beta-adrenergic agonist, was associated with an increase in the risk of asthma death. The results of these studies were criticized because of methodologic problems in the choice and selection of control subjects; the different methods used to gather exposure data in cases and control subjects; and because of inadequate classification and adjustment for asthma severity. In response to this controversy, a new study is underway, the Saskatchewan Asthma Epidemiology Project. The SAEP includes two complementary studies, an historic cohort and a case-control analysis, that employ the computerized databases of the Saskatchewan Health Department. A unique aspect of the SAEP is the attempt to incorporate knowledge of asthma physiology and management into the design of the studies. Specifically, the study design recognized the role of antiinflammatory drugs in asthma treatment; the distinction between asthma death and near-fatal asthma; the severity of asthma; patterns of drug use; and the distinction between inadequate clinical care and disease severity. The strategies we employed in the SAEP may prove helpful to investigators whenever clinical and biologic processes create sources of potential bias requiring special procedures for the design and analysis of epidemiologic studies.

Chest. 1991;100(6):1592-1596. doi:10.1378/chest.100.6.1592

A study was conducted to determine the bronchoscopic and chest roentgenographic findings associated with a positive TBNA. One hundred fifty-seven of 465 patients who were diagnosed for the first time as having carcinoma of the lung had a positive aspirate. Bronchoscopic findings associated with a positive TBNA of N2 nodes were carinal widening and endobronchial disease, especially of the right upper lobe. Mediastinal adenopathy noted on chest roentgenograms and subcarinal nodes on CAT scans were associated with a positive aspirate as well. In 34 of 465 patients, TBNA was the only means of establishing the diagnosis of pulmonary malignancy. A useful, simple and safe procedure, TBNA can be used to stage the mediastinum in patients with lung cancer and is most likely to be positive with endobronchial and nodal disease. It can also facilitate therapeutic decision-making in patients whose surgical candidacy is marginal.

Chest. 1991;100(6):1597-1600. doi:10.1378/chest.100.6.1597

We compared the effectiveness of albuterol with isoproterenol as a bronchodilator for use in pulmonary function testing. A total of 180 patients presenting for routine pulmonary function testing were randomly assigned to receive 5 mg of either albuterol or isoproterenol by compressed air nebulizer. Forced expiratory maneuvers were performed before, 5 min after, and 10 min after bronchodilator administration. The average increase in FEV1 and FVC did not differ between drugs. Also, the fraction of patients achieving a clinically significant bronchodilator response did not differ between drugs. Importantly, there was no significant difference between average 5 and 10 min postbronchodilator values for FEV1 or FVC for either bronchodilator, suggesting that a peak response was reached by 5 min. These results show no advantage of isoproterenol over albuterol in terms of potency or speed of action. Given the well-known cardiovascular side effects of isoproterenol, albuterol is the preferable agent for use in pulmonary function testing.

Chest. 1991;100(6):1601-1606. doi:10.1378/chest.100.6.1601

To investigate the prognostic utility of the morphologic and immunologic evaluation of BAL cell populations in determining mortality risk, we analyzed BAL data obtained from 115 patients infected with HIV-1. Forty fatal outcomes occurred within 73 patients with OI. The OI patients who died showed a significant increase in neutrophils with respect to surviving patients. Furthermore, the finding of a BAL neutrophilia in HIV-1-infected patients with OI strongly correlated with a high risk of death. Among 42 cases without OI, 11 patients died. Patients without OI who had a fatal outcome showed an increase in CD3+ and CD8+ BAL lymphocytes with respect to the survivors. The presence of a lymphocytic alveolitis was associated with a significant increase in the mortality rate. Taken together our data suggest that the evaluation of the BAL cell populations might be useful in predicting the risk of fatal outcome in patients with HIV-1 infection.

Chest. 1991;100(6):1607-1613. doi:10.1378/chest.100.6.1607

The role of Pseudomonas aeruginosa infection in airway mucosal permeability was studied in 16 patients with chronic bronchitis by measuring the amounts of radiolabeled albumin in sputum. One group (A) consisted of six patients (two female, four male, 53 +/- 6 years, SEM) with chronic P aeruginosa infection for 5 +/- 0.9 years. Another group (B) consisted of ten patients (five female, five male, 67 +/- 4 years) without P aeruginosa infection for at least two years. No significant differences between groups A and B were found in the volume of sputum (63 +/- 21 ml/day in group A and 45 +/- 8 ml/day in group B, p = 0.44), the obstructive changes (FEV1 of 57 +/- 6 percent in group A and 51 +/- 4 percent in group B), or the duration of disease (19 +/- 4 years in group A and 14 +/- 4 years in group B). Saliva, sputum, and serum samples were collected at intervals of 2 h over an 8-h period, and at 24 h after intravenous administration of 131I-labeled human albumin. For counting, free 131I was removed by dialysis. Radiocounts (cpm) of saliva were significantly smaller than those of sputum or serum. The cpm from each sputum sample was divided by serum cpm at the time of each sampling. Group A showed significantly higher values in the ratio of sputum- to serum-cpm than did group B at all sampling times. Furthermore, the ratios at 2 and 4 h after 131I-albumin injection significantly correlated with sputum volume per day, whereas they did not correlate with any other factors (age, obstructive impairment, and duration of disease). These findings suggest that chronic P aeruginosa infection produces an increase in airway mucosal permeability to albumin.

Chest. 1991;100(6):1614-1618. doi:10.1378/chest.100.6.1614

The role of Aspergillus species as a pathogen in acquired immunodeficiency syndrome (AIDS) has not been clearly defined. From 1984 to 1989, more than 2,000 AIDS patients were seen at Beth Israel Medical Center, New York. Aspergillus was isolated in ten patients; seven had invasive disease and three had noninvasive disease. Invasive pulmonary aspergillosis (IPA) was diagnosed in six patients and invasive renal aspergillosis was found in one patient. Five were homosexual men and two were intravenous drug users. At presentation, all ten had fever, seven had cough, eight had dyspnea, and five had pleuritic chest pain. Chest roentgenograms revealed focal infiltrates in six patients, bilateral interstitial infiltrates in two patients, and bilateral pneumothoraces in one patient. Predisposing conditions included corticosteroid therapy in four, granulocytopenia (less than 1,000/cu m) in two, and broad-spectrum antibiotic therapy in five. Three of the four patients receiving corticosteroids received them as adjuvant therapy for Pneumocystis carinii pneumonia (PCP). Aspergillus was identified antemortem in eight patients, in bronchoalveolar lavage (BAL) fluid in six, in transbronchial biopsy specimen in three, in open lung biopsy specimen in one, and postmortem in one patient. Six of seven patients had at least one concomitant pulmonary process. Six underwent necropsy and findings showed IPA in three, disseminated aspergillosis in two, and PCP in one. Invasive aspergillosis, although significant, is uncommon in AIDS. When Aspergillus is isolated in the setting of corticosteroid therapy, antibiotics, or granulocytopenia, one must suspect invasive disease.

Chest. 1991;100(6):1619-1636. doi:10.1378/chest.100.6.1619

The objective of this study was to refine the APACHE (Acute Physiology, Age, Chronic Health Evaluation) methodology in order to more accurately predict hospital mortality risk for critically ill hospitalized adults. We prospectively collected data on 17,440 unselected adult medical/surgical intensive care unit (ICU) admissions at 40 US hospitals (14 volunteer tertiary-care institutions and 26 hospitals randomly chosen to represent intensive care services nationwide). We analyzed the relationship between the patient's likelihood of surviving to hospital discharge and the following predictive variables: major medical and surgical disease categories, acute physiologic abnormalities, age, preexisting functional limitations, major comorbidities, and treatment location immediately prior to ICU admission. The APACHE III prognostic system consists of two options: (1) an APACHE III score, which can provide initial risk stratification for severely ill hospitalized patients within independently defined patient groups; and (2) an APACHE III predictive equation, which uses APACHE III score and reference data on major disease categories and treatment location immediately prior to ICU admission to provide risk estimates for hospital mortality for individual ICU patients. A five-point increase in APACHE III score (range, 0 to 299) is independently associated with a statistically significant increase in the relative risk of hospital death (odds ratio, 1.10 to 1.78) within each of 78 major medical and surgical disease categories. The overall predictive accuracy of the first-day APACHE III equation was such that, within 24 h of ICU admission, 95 percent of ICU admissions could be given a risk estimate for hospital death that was within 3 percent of that actually observed (r2 = 0.41; receiver operating characteristic = 0.90). Recording changes in the APACHE III score on each subsequent day of ICU therapy provided daily updates in these risk estimates. When applied across the individual ICUs, the first-day APACHE III equation accounted for the majority of variation in observed death rates (r2 = 0.90, p less than 0.0001).

Chest. 1991;100(6):1637-1642. doi:10.1378/chest.100.6.1637

The impact of analysis of the severity of illness on the in-hospital mortality was reviewed retrospectively on a cohort of patients admitted to a coronary care unit. Three hundred and eighty-six patients were admitted during the study period, with diagnoses including myocardial infarction (49 percent), unstable angina (23 percent), arrhythmias (11 percent), congestive heart failure (5 percent), and nondiagnostic chest pain (5 percent). Total in-hospital mortality was 13 percent. Severity of illness was measured using the acute physiology and chronic health evaluation (APACHE 2) score. Mortality was found to be influenced by admitting diagnosis (p = 0.01), source of referral (p = 0.03), and APACHE 2 score (nonsurvivors, 16.5 +/- 10.1; survivors, 8.5 +/- 4.8; p less than 0.001). The receiver operating characteristic (ROC) curve for the APACHE 2 confirmed it as a predictor of mortality, with an area under the curve (+/- SE) of 0.75 +/- 0.04 (95 percent confidence limits, 0.67 to 0.83). Logistic regression analysis showed the APACHE 2 score and the diagnosis on admission to be significant multivariate predictors of mortality, and a series of diagnosis-specific coefficients are presented. We conclude that the APACHE 2 score is a useful tool for the overall assessment and management of the CCU, as it is in the multidisciplinary medical-surgical intensive care unit.

Chest. 1991;100(6):1643-1646. doi:10.1378/chest.100.6.1643

Enteral delivery of nutrients is important for optimal treatment of critically ill patients. It maintains gut digestive and barrier functions, decreases gut bacterial translocation, decreases the incidence of sepsis, and improves outcome. Gastric emptying is impaired in many critically ill patients and feeding into a gastroparetic stomach leads to large gastric residuals and aspiration. We describe a simple bedside technique for placement of small bowel feeding tubes. Using this technique, we successfully placed 213/231 (92 percent) of feeding tubes in critically ill patients. Three percent were in the first portion of the duodenum, 25 percent in the second portion, 47 percent in the third portion, and 17 percent in the proximal jejunum. The average time for placement of small bowel feeding tubes was 40 +/- 14 min (mean +/- SD). Abdominal roentgenograms failed to properly locate 13 (6 percent) tubes. The most accurate and cheapest methods for confirming small bowel location of feeding tubes were bile aspiration, pH change from acidic to basic, and blue dye injection.

Chest. 1991;100(6):1647-1654. doi:10.1378/chest.100.6.1647

STUDY OBJECTIVE: We evaluated the ability of three independent reviewers (R1, R2, R3) using waveform analysis to accurately identify confirmed valid PCWP tracings, and their ability to consistently report the PCWP numerical value. DESIGN: Sixty PA and PCWP tracings were prospectively obtained and blindly reviewed by three independent critical care physicians. SETTING: The medical ICU of Wilford Hall USAF Medical Center. PATIENTS OR PARTICIPANTS: Twenty mechanically ventilated patients with PA catheters inserted for hemodynamic assessment. INTERVENTIONS: Sixty PA and PCWP tracings were reviewed blindly and independently for acceptability using waveform criteria by three critical care physicians. While recording all 60 tracings, blood was aspirated from the distal port of the PA catheter with the balloon "wedged" and blood gas analysis was done. Each reviewer analyzed the PCWP tracings for validity using waveform criteria, and reported a numerical PCWP reading for those tracings judged valid by waveform criteria. Reviewer sensitivity, specificity and accuracy in performing waveform analysis were assessed by comparing their predictions with those tracings that were confirmed their predictions with those tracings that were confirmed valid by the aspiration of pulmonary capillary blood. Inter-reviewer agreement upon which validity of PCWP tracings was based and reviewer agreement on the numerical PCWP reading were also assessed. All tracings were blindly reviewed by each physician, first without and then with an AP tracing to define end-expiration. MEASUREMENT AND RESULTS: Thirty-eight of 60 PCWP tracings were confirmed valid by the aspiration of pulmonary capillary blood. In the remaining 22 tracings, mixed venous blood was aspirated with the balloon wedged, and tracing validity was unconfirmed. Reviewer accuracy in identifying was 50 percent for R1, 65 percent for R2 and 57 percent for R3. No reviewer's accuracy was significantly different from a random guess which would yield an accuracy of 50 percent. Agreement by all three reviewers in identifying valid PCWP tracings using waveform analysis varied from 37 percent in the absence of an AP tracing to 66 percent when an AP tracing was available to identify end-expiration (p less than 0.003). Agreement by all three reviewers on the PCWP numerical reading (within 4 mm Hg) was 79 percent without an AP tracing and 96 percent with an AP tracing (p = NS). The numerical reading reported by the ICU nurses and house staff correlated closely with the reviewers' readings. Agreement with the reported PCWP reading was improved only for R2 by the addition of an AP tracing. CONCLUSION: We conclude that the validation of PCWP tracings by waveform analysis is subject to interobserver variability, and reviewer accuracy in identifying confirmed valid tracings was no better than a random guess. Agreement on the numerical PCWP reading was high among the reviewers as was agreement by each individual reviewer with the reported PCWP. Finally, the presence of an AP tracing, to define end-expiration, adds little to the interpretation of the PCWP numerical reading by experienced physicians.

Chest. 1991;100(6):1655-1659. doi:10.1378/chest.100.6.1655

Because T-piece breathing may impair oxygenation, the best airway pressure from which to extubate ventilated patients is controversial. We compared the effects of extubation after 1 h of either CPAP 5 and T-piece/ZEEP. Once weaned from mechanical ventilation and breathing spontaneously, 106 patients were randomized to 1 h CPAP or 1 h T-piece/ZEEP, following which patients were extubated and mask O2 administered. No significant difference existed between groups in age, sex, HR, BP, FIO2, PaCO2 or PaO2. However, P(A-a)O2 was significantly greater at 120 min in the CPAP group. Within the CPAP group, P(A-a)O2 was also significantly worse at 120 vs 0 min. Nineteen T-piece patients showed improved P(A-a)O2 at 120 min compared with only ten CPAP patients. Three CPAP and two T-piece patients subsequently required reintubation. This study demonstrates that use of a T-piece dose not impair arterial oxygenation and may in fact be superior to direct extubation from CPAP 5.

Chest. 1991;100(6):1660-1667. doi:10.1378/chest.100.6.1660
Abstract
Topics: bronchoscopy
Chest. 1991;100(6):1668-1675. doi:10.1378/chest.100.6.1668

A mail survey of this type has several inherent drawbacks. First, answers to some of the questions, particularly those pertaining to complication rates, rely on the memory of participants. Second, the wording of certain questions may have imparted different meanings. Third, the format of the questionnaire may have confused some. Fourth, one cannot expect that all questionnaires will be answered fully. Fifth, as indicated by several respondents, several important topics (eg, topical anesthetic agents and mode of their delivery, prophylaxis against infective endocarditis, tracheobronchial stent placement, endobronchial intraluminal radiotherapy) were not included. Many respondents suggested inclusion of these and other questions in future surveys. Nevertheless, in the absence of any survey looking into a large number of bronchoscopy-related practices, mail surveys have the advantage of reflecting nationwide practice rather than results from selected centers, and this report provides some insight into bronchoscopy practices in North America. While the results indicate the present trends in bronchoscopy practices in North America, they do not establish or recommend any standards in bronchoscopy.

Topics: bronchoscopy
Chest. 1991;100(6):1676-1684. doi:10.1378/chest.100.6.1676
Chest. 1991;100(6):1685-1686. doi:10.1378/chest.100.6.1685
Abstract
Chest. 1991;100(6):1694-1702. doi:10.1378/chest.100.6.1694

The pulmonary reimplantation response (PRR) is a form of membrane permeability pulmonary edema occurring in lung transplants. The severity of the PRR reflects the quality and duration of lung graft preservation. Free radicals formed during ischemia with reperfusion in the autotransplanted dog lung may play a role in producing PRR. We hypothesized that the addition of reduced glutathione (GSH) to the preservative solution could decrease PRR if hydroperoxides are being formed. Six dogs underwent left lung autotransplantation after the lung was flushed with Euro-Collins solution (EC). These dogs demonstrated radiographic and histopathologic evidence of bilateral pulmonary edema, greatest in the transplanted left lung. They also had increases in lung wet to dry weight (W/D) ratios in both lungs (left, 12.0 +/- 0.9; right, 10.1 +/- 0.8) as compared with a group of five unmanipulated control animals (left, 6.0 +/- 0.5; right, 7.0 +/- 0.4). Malondialdehyde (MDA) concentrations were significantly increased in the transplanted left lungs (14 +/- 4) from this group as compared with the controls (5 +/- 7). Five additional dogs underwent left lung autotransplantation with GSH added to the EC cryopreservation fluid. These animals did not develop histologic or radiographic evidence of pulmonary edema, and W/D ratios as well as MDA concentrations were not different from those in controls. To evaluate the effect of ischemia alone on changes in lung GSH concentrations, ten additional dogs underwent left pneumonectomy. Left lungs were cryopreserved in EC + GSH. In five of the animals, the right lung was removed and preserved in EC alone. In the other five animals, the right lung remained in vivo for 3 h and was then removed. Lung GSH concentrations were doubled after 3 h of ischemia when incubated in EC + GSH compared to in vivo controls and to EC-treated lungs. These data suggest that GSH added to the preservation fluid prevents PRR following transplantation and that lung GSH concentrations actually increase during preservation prior to reimplantation and reperfusion if the lung graft is exposed to GSH in the preservation fluid.

Chest. 1991;100(6):1703-1711. doi:10.1378/chest.100.6.1703

Since the sepsis syndrome is associated with depressed vascular reactivity, it may be incorrect to assume that pharmacologically mediated changes in cardiac output will be proportionately distributed at the regional level of the circulation. We examined the effect of hyperdynamic sepsis and the concurrent administration of the vasodilatory prostaglandin (PGE1) on the regional distribution of blood flows (Q) in unanesthetized sheep rendered septic by cecal ligation and perforation. Systemic Q progressively increased throughout a 48-h study period after cecal ligation and perforation. Simultaneously, organ Q, measured by the radioactive microsphere technique, was depressed to the pancreas, but increased to the heart, gallbladder, brain, and colon; the increased Q to both heart and gallbladder was greater than the simultaneous increase in systemic Q in this septic study. With the infusion of PGE1 (1 microgram/kg/min), mean arterial perfusing pressures fell, while the cardiac index increased further over that recorded during the 48-h septic study. Despite this depression in arterial pressures, the only significant effect of PGE1 on the interorgan distribution of Q was in the renal circulation, where it was demonstrated that kidney Q fell. We conclude that (1) hyperdynamic and normotensive sepsis exerted nonhomogeneous effects on the distribution of organ Q, and (2) an increased systemic Q during PGE1 infusion was proportionately distributed to all organs, except the kidneys, where Q paradoxically fell. The latter finding suggests that the regulation of kidney Q may be depressed across the normal range of arterial perfusing pressures in the sepsis syndrome. Further investigation is essential to understand the effect of clinical interventions on the control of tissue O2 flux at both the regional and microregional levels of the circulation.

Chest. 1991;100(6):1712-1714. doi:10.1378/chest.100.6.1712
Chest. 1991;100(6):1715-1717. doi:10.1378/chest.100.6.1715

Acute histoplasmosis is generally a benign, self-limited pulmonary infection. Although Histoplasma capsulatum pneumonitis is common, pleural effusions associated with histoplasmosis are quite rare, and massive pleural effusions have not been reported. There have been several reports of pericardial fibrosis secondary to histoplasmosis, but epicardial fibrosis has not been described. We report a biopsy-proven case of histoplasmosis initially associated with recurrent massive pleural effusions and excessive pleural fibrosis causing a trapped lung. The patient later developed constrictive pericarditis. Despite pericardiectomy, severe cor pulmonale occurred, and the patient died. Necropsy demonstrated fibrosis of the epicardium.

Chest. 1991;100(6):1717-1719. doi:10.1378/chest.100.6.1717

Lung transplantation has resulted in dramatic functional improvement in patients with end-stage pulmonary diseases. Among the complications of lung transplantation are dehiscence and stenosis at the site of the bronchial or tracheal anastomosis. In this case report, we describe a single lung transplant recipient in whom partial bronchial dehiscence, followed by exuberant growth of granulation tissue, resulted in obstruction of the bronchial lumen. After mechanical dilation failed to produce lasting relief of bronchial obstruction, a novel approach to this problem was successfully employed: YAG laser phototherapy was used to remove obstructing granulation tissue, followed by application of a preparation derived from autologous blood platelets to promote epithelialization of the bronchial anastomosis. The bronchus remains patent and fully epithelialized six months after therapy.

Chest. 1991;100(6):1720-1721. doi:10.1378/chest.100.6.1720

We describe a patient with PHG who presented with multiple cavitary calcified nodules. Laboratory evaluations revealed that she had serum immune abnormalities, and a histoplasmin skin test yielded positive results. Her Histoplasma infection may have produced a hyperimmune reaction that resulted in PHG and the calcified nodules.

Chest. 1991;100(6):1721-1722. doi:10.1378/chest.100.6.1721

A 60-year-old man presented with features of superior vena cava (SVC) obstruction. On evaluation, he was diagnosed as having angioimmunoblastic lymphadenopathy with dysproteinemia (AILD). SVC obstruction due to AILD, to our knowledge, has not been described.

Chest. 1991;100(6):1723-1724. doi:10.1378/chest.100.6.1723

A 35-year-old man with the acquired immunodeficiency syndrome (AIDS) presented with a multitude of constitutional symptoms, fever, and marked intrathoracic lymphadenopathy. Results of initial diagnostic examination were unrevealing, and bronchoscopy with fine-gauge flexible transbronchial needle aspiration (TBNA) of subcarinal lymph nodes was performed. Two aspirates were obtained, one for cytologic study and the other for acid-fast smear. Despite obtaining acid-fast smears from numerous sites, only TBNA provided evidence of acid-fast organisms and prompted early antimycobacterial therapy. We believe this is the first report of mycobacterial intrathoracic lymphadenopathy diagnosed by TBNA.

Chest. 1991;100(6):1724-1725. doi:10.1378/chest.100.6.1724

A 7-year-old white boy with the long QT syndrome began to experience recurrent syncope associated with torsade de pointes ventricular tachycardia in spite of beta-blocker therapy. The patient was therefore given a combined alpha- and beta-blocking agent (labetalol) with complete suppression of the syncopal episodes. This suggests a role for combined alpha- and beta-blocking agents in the therapy of arrhythmias associated with the long QT syndrome.

Chest. 1991;100(6):1726-1728. doi:10.1378/chest.100.6.1726

A young nonsmoking woman presented with severe dyspnea, exercise desaturation, and chest discomfort. Pathologic and histochemical findings revealed pulmonary lymphangioleiomyomatosis (LAM) as the primary abnormality. In addition, there were multiple noncaseating granulomas with special stains and cultures negative for organisms. This highly unusual combination of pathologic findings might suggest the presence of coexistent sarcoidosis in our patient with LAM.

Chest. 1991;100(6):1728-1730. doi:10.1378/chest.100.6.1728

A 62-year-old woman was noted to have complete heart block immediately following an exercise stress test. Coronary arteriography subsequently revealed a significant lesion in the right coronary artery, which was successfully dilated. Thallium-exercise testing following angioplasty showed no evidence of inducible ischemia and no arrhythmia was seen, supporting the idea that exercise-related heart block may occur secondary to myocardial ischemia.

Chest. 1991;100(6):1730-1732. doi:10.1378/chest.100.6.1730

Severe pulmonary edema occurred in a patient during the third trimester of two consecutive pregnancies, 17 months apart. Noncardiac origin of the pulmonary edema was demonstrated by normal pulmonary capillary wedge pressures, normal roentgenographic cardiac dimensions with absence of effusions, normal echocardiographic ejection fraction, and elevated thermodilution cardiac outputs; moderate reduction in serum albumin levels may have contributed. In the setting of pregnancy-induced hypertension, the development of ARDS on each occasion suggests a pathophysiologic link.

Chest. 1991;100(6):1733-1735. doi:10.1378/chest.100.6.1733

A 34-year-old woman seronegative for the human immunodeficiency virus presented with recurrent, bilateral pneumothoraces. She also had bibasilar interstitial and alveolar infiltrates, and histologic examination was consistent with lymphocytic interstitial pneumonitis. To our knowledge, this is the first documented case of lymphocytic interstitial pneumonitis presenting with recurrent pneumothoraces.

Chest. 1991;100(6):1735-1737. doi:10.1378/chest.100.6.1735

Intubation of the left main bronchus via a tracheostomy tube was performed in a patient with local recurrence of lung cancer associated with invasion and obstruction of the left main bronchus after right sleeve pneumonectomy. The result was satisfactory not only for preventing asphyxia, but also for maintaining the patency of the airway after extubation of the endotracheal tube.

Chest. 1991;100(6):1737-1738. doi:10.1378/chest.100.6.1737

We report the case of a patient who developed granulomas in a ten-year-old tattoo. Total body gallium scanning detected the presence of bilateral hilar adenopathy not apparent on routine chest roentgenograms and thus established a diagnosis of systemic sarcoidosis.

Chest. 1991;100(6):1739a. doi:10.1378/chest.100.6.1739a
Chest. 1991;100(6):1739b-1741. doi:10.1378/chest.100.6.1739b
Chest. 1991;100(6):1741b. doi:10.1378/chest.100.6.1741b
Abstract
Chest. 1991;100(6):1743a. doi:10.1378/chest.100.6.1743a
Abstract
Topics: atopy , lung cancer
Chest. 1991;100(6):1743b-1744. doi:10.1378/chest.100.6.1743b
Abstract

Communications to the Editor

Chest. 1991;100(6):1740-1741. doi:10.1378/chest.100.6.1740
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Abstract
Chest. 1991;100(6):1742. doi:10.1378/chest.100.6.1742-a
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Abstract
Chest. 1991;100(6):1742-1743. doi:10.1378/chest.100.6.1742-b
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Chest. 1991;100(6):1744. doi:10.1378/chest.100.6.1744-a
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Chest. 1991;100(6):1744. doi:10.1378/chest.100.6.1744-b
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    Print ISSN: 0012-3692
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