Tracheobronchial foreign bodies

Aspiration of tracheobronchial foreign bodies occurs more commonly in children, but under certain circumstances, it also can occur in adults. The most common symptoms are choking followed by a protracted cough. Physical examination findings include fever, stridor, retractions, and decreased breath sounds. Radiographic imaging can be helpful if the object aspirated is radiopaque or if there are signs of hyperexpansion on expiration. Negative-imaging studies, however, do not exclude the presence of a foreign body in the airway. The longer a foreign body resides in the airway, the more likely it is to migrate distally. When this occurs, symptoms of chronic cough and wheezing may mimic an asthmalike condition. Bronchoscopy is indicated in this situation to evaluate the airway thoroughly. If a foreign body is present, extraction can be performed with flexible or rigid bronchoscopy. If flexible bronchoscopy is attempted, it is imperative that the bronchoscopist is familiar with rigid bronchoscopy and has the equipment immediately available should danger to the airway occur. The procedure is generally safe and well tolerated. Many patients are managed under general anesthesia, but foreign bodies often can be removed with a flexible bronchoscope with the patient under local anesthesia. Surgery should be performed only as a last resort and rarely is necessary.

External-beam radiation therapy in the treatment of diffuse tracheobronchial amyloidosis

Tracheobronchial amyloidosis is characterized by deposits of amyloid in airway walls. No effective treatment is known. We describe a 59-year-old woman who presented with increasing symptoms of airway obstruction due to diffuse deposition of amyloid throughout her tracheobronchial tree. She was treated with external-beam radiation therapy (20 Gy) with marked improvement in her symptoms, effort tolerance, bronchoscopic appearance, and forced expiratory volume in 1 second (1.39 L to 1.97 L [42%]). This improvement was maintained during 21 months of follow-up.

Strategic performance management: development of a performance measurement system at the Mayo Clinic

Managing and measuring performance become exceedingly complex as healthcare institutions evolve into integrated health systems comprised of hospitals, outpatient clinics and surgery centers, nursing homes, and home health services. Leaders of integrated health systems need to develop a methodology and system that align organizational strategies with performance measurement and management. To meet this end, multiple healthcare organizations embrace the performance-indicators reporting system known as a "balanced scorecard" or a "dashboard report." This discrete set of macrolevel indicators gives senior management a fast but comprehensive glimpse of the organization's performance in meeting its quality, operational, and financial goals. The leadership of outpatient operations for Mayo Clinic in Rochester, Minnesota built on this concept by creating a performance management and measurement system that monitors and reports how well the organization achieves its performance goals. Internal stakeholders identified metrics to measure performance in each key category. Through these metrics, the organization links Mayo Clinic's vision, primary value, core principles, and day-to-day operations by monitoring key performance indicators on a weekly, monthly, or quarterly basis.

Solitary pulmonary nodules: clinical prediction model versus physicians

OBJECTIVE

To determine whether a clinical prediction model developed to identify malignant lung nodules based on clinical data and radiologic lung nodule characteristics could predict a malignant lung nodule diagnosis with higher accuracy than physicians.

MATERIAL AND METHODS

One hundred cases were obtained by using a stratified random sample from a retrospective cohort of 629 patients with newly discovered 4- to 30-mm radiologically indeterminate solitary pulmonary nodules (SPNs) on chest radiography. A chest radiologist, pulmonologist, thoracic surgeon, and general internist made predictions of a malignant lesion and recommendations for management (thoracotomy, transthoracic needle aspiration biopsy, or observation) on the basis of radiologic and clinical data used to develop the clinical prediction rule. The predictions of a malignant lung nodule were compared with the probability of malignant involvement from a previously validated clinical prediction model to identify malignant nodules on the basis of three clinical characteristics (age, smoking status, and history of cancer greater than or equal to 5 years previously) and three radiologic characteristics (nodule diameter, spiculation, and upper lobe location).

RESULTS

Receiver operating characteristic analysis showed no significant difference between the logistic model and the physicians' predictions. Calibration curves revealed that physicians overestimated the probability of a malignant lesion in patients with low risk of malignant disease by the prediction rule; this finding suggests a potential for the decision rule to improve the management of patients with SPNs that are likely to be benign.

CONCLUSION

The prediction model was not better than physicians' predictions of malignant SPNs. The prediction rule may have potential to improve the management of patients with SPNs that are likely to be benign.

Photodynamic therapy for bronchogenic carcinoma

Photodynamic therapy has been used in the management of early lung cancer since the 1980s. It appears to be effective as a curative therapy for superficial squamous cell carcinomas and as palliative therapy in obstructive cancers of the tracheobronchial tree. New photosensitizers that have a deeper penetration and less photosensitivity are needed.

Human immunodeficiency virus infection and pulmonary hypertension: two new cases and a review of 86 reported cases

In this article, we describe pulmonary hypertension in two men (31 and 43 years of age) with human immunodeficiency virus (HIV) infection who were examined at Mayo Clinic Rochester. Among 88 reported cases (including the two current ones) of HIV- or acquired immunodeficiency syndrome (AIDS)-associated pulmonary hypertension, 61% were male; the age range was 2 to 56 years (mean, 32). Dyspnea was the usual initial symptom. Of the 74 patients in whom pulmonary artery pressure was recorded or calculated by echocardiography, systolic pressures ranged from 49 to 118 mm Hg (mean, 68). Of the 33 cases in which lung tissue was evaluated microscopically, 28 (85%) were of the plexogenic variant of pulmonary arterial hypertension. Of the other five cases examined histologically, three consisted of thrombotic pulmonary arteriopathy (one was due to recurrent thromboembolism, and the other two were due to in situ thrombosis), and two were of pulmonary venoocclusive disease. No correlation existed between either CD4 counts or a history of pulmonary infections and the development of pulmonary hypertension. In 15 of the 88 patients (17%), confounding factors for hypertensive pulmonary vascular disease were present, including coexisting liver disease in 13 and coagulation abnormalities in 2. In 83% of the patients, the development of pulmonary hypertension seems to have been related primarily to the chronic HIV infection. Pulmonary hypertension was more rapidly progressive in patients with HIV or AIDS than in those with primary pulmonary hypertension; the reported time intervals between onset of symptoms and diagnosis were 6 months and 30 months, respectively. The 1-year survival rate for patients with HIV and pulmonary hypertension was 51%, based on the follow-up data compiled from the 63 patients in whom it was described; this compares with a 1-year survival rate of 68% for patients with primary pulmonary hypertension. Death was considered a direct consequence of pulmonary hypertension in 29 (76%) of the 38 fatal cases.

Photodynamic therapy for early stage squamous cell carcinoma of the lung

OBJECTIVE

To study the effectiveness of photodynamic therapy (PDT) as a therapeutic strategy in roentgenographically occult squamous cell carcinoma of the lung.

MATERIAL AND METHODS

A carefully selected group of 21 patients (with 23 cancers) who had early stage squamous cell carcinoma of the lung and were eligible for surgical treatment were offered PDT as an alternative to resection. Patients underwent close follow-up with bronchoscopic surveillance and were offered resection if cancer persisted after no more than two sessions of PDT.

RESULTS

A complete response was identified in 15 patients (16 cancers) after an initial PDT session. A complete response that lasted longer than 12 months was noted in 11 patients (52%). After PDT, the minimal follow-up period was 24 months. A subsequent primary lung cancer developed in 5 of the 21 patients (24%). Ten patients ultimately had surgical treatment, in 3 (30%) of whom N1 disease was identified at the time of resection. Two patients refused a surgical procedure and received alternative therapy. Therefore, nine patients (43%) were spared an operation (95% confidence interval, 21.8 to 66.6%). The mean duration of follow-up for these nine patients was 68 months (range, 24 to 116).

CONCLUSION

On the basis of this investigation, we can conclude with 95% confidence that at least 22% of patients with early stage squamous cell lung cancer who are candidates for PDT can be spared surgical resection.

Diagnostic tests for lung cancer

Bronchogenic carcinoma is the leading cause of cancer death in both men and women in the United States. There has been little impact on the overall mortality from lung cancer in the past 20 years. Diagnostic tests such as routine chest x-ray and sputum cytology have proven to be ineffective in altering this mortality. The identification of risk factors, including obstructive lung disease and familial tendencies to develop lung cancer, may allow for specific strategies that will impact this mortality. Additionally, biological markers are being identified in sputum specimens that may allow identification of premalignant changes prior to morphologic changes seen in sputum cytology. Radiologic testing such as CT scans with contrast enhancement and positive emission tomography may also aid in the early detection of peripheral lung nodules. It is through the development of these new technologies that we have an opportunity to alter overall lung cancer mortality. Here we review several articles reporting exciting new diagnostic technology.

The probability of malignancy in solitary pulmonary nodules. Application to small radiologically indeterminate nodules

BACKGROUND

A clinical prediction model to identify malignant nodules based on clinical data and radiological characteristics of lung nodules was derived using logistic regression from a random sample of patients (n = 419) and tested on data from a separate group of patients (n = 210).

OBJECTIVE

To use multivariate logistic regression to estimate the probability of malignancy in radiologically indeterminate solitary pulmonary nodules (SPNs) in a clinically relevant subset of patients with SPNs that measured between 4 and 30 mm in diameter.

PATIENTS AND METHODS

A retrospective cohort study at a multispecialty group practice included 629 patients (320 men, 309 women) with newly discovered (between January 1, 1984, and May 1, 1986) 4- to 30-mm radiologically indeterminate SPNs on chest radiography. Patients with a diagnosis of cancer within 5 years prior to the discovery of the nodule were excluded. Clinical data included age, sex, cigarette-smoking status, and history of extrathoracic malignant neoplasm, asbestos exposure, and chronic interstitial or obstructive lung disease; chest radiological data included the diameter, location, edge characteristics (eg, lobulation, spiculation, and shagginess), and other characteristics (eg, cavitation) of the SPNs. Predictors were identified in a random sample of two thirds of the patients and tested in the remaining one third.

RESULTS

Sixty-five percent of the nodules were benign, 23% were malignant, and 12% were indeterminate. Three clinical characteristics (age, cigarette-smoking status, and history of cancer [diagnosis, > or = 5 years ago]) and 3 radiological characteristics (diameter, spiculation, and upper lobe location of the SPNs) were independent predictors of malignancy. The area (+/-SE) under the evaluated receiver operating characteristic curve was 0.8328 +/- 0.0226.

CONCLUSION

Three clinical and 3 radiographic characteristics predicted the malignancy in radiologically indeterminate SPNs.

Future therapeutic procedures

Management of disorders of the tracheobronchial tree have advanced significantly since the first use of the rigid bronchoscope by Gustav Killian. The addition of the flexible bronchofiberscope by Shigeto Ikeda offered a second generation of new therapeutic opportunities. The future use of thoracic endoscopy will depend upon the application and improvement of technologies that currently exist in addition to those not yet developed. There are three current technologies which are being improved and may be applicable in the future management of diseases of the tracheobronchial tree and these include cryotherapy, electrosurgery, and photodynamic therapy.

The documentation of thoracic endoscopy

Thoracic endoscopy encompasses bronchoscopy, esophagoscopy, laryngoscopy, mediastinoscopy, and thoracoscopy (pleuroscopy). In this article, the role of documentation as it applies to bronchoscopy is discussed. However, the discussion is generally applicable to other thoracic endoscopy procedures.

Cytokine production at the site of disease in chronic eosinophilic pneumonitis

Chronic eosinophilic pneumonitis (CEP) is characterized by longstanding respiratory symptoms accompanied by a massive pulmonary eosinophil infiltration. We hypothesized that cytokine(s) produced in the disease sites are implicated in the pathophysiology of CEP. We studied peripheral blood and bronchoalveolar lavage fluids (BALF) obtained from two lung segments of a patient with CEP. Seventy times more eosinophils were found in the BALF from an involved lung segment (showing patchy opacification on a chest roentgenogram) than from an uninvolved segment. The eosinophil-active cytokines interleukin-5 (IL-5), IL-6, and IL-10 were strikingly elevated in the BALF from the involved lung segment, whereas no or minimal levels of these cytokines were detectable in the BALF from the uninvolved segment or serum, respectively. Leukocytes in the involved lung segment, but not those in peripheral blood, expressed messenger ribonucleic acid (mRNA) for IL-5, IL-6, and IL-10. In contrast, IL-2, IL-3, IL-4, interferon-gamma (IFN-gamma), granulocyte-macrophage colony-stimulating factor (GM-CSF), and tumor necrosis factor-alpha (TNF-alpha) were not detected in any sample. These findings suggest that increased production of several cytokines, such as IL-5, IL-6, and IL-10, in the involved lung segment, but not in the uninvolved lung segment or peripheral blood, is a critical pathophysiologic feature of CEP.

Photodynamic therapy. Its use in the management of bronchogenic carcinoma

Photodynamic therapy is an investigational treatment of various types of carcinoma. It involves a photosensitizing agent which, when exposed to light of the proper wavelength, forms toxic oxygen radicals that result in cell death. This article describes its current use in the management of bronchogenic carcinoma.

Tests for diagnosis and staging of bronchogenic carcinoma

Bronchogenic carcinoma continues to be a significant cause of both morbidity and mortality. Despite the attempts to reduce exposure to known causative agents, such as tobacco, the incidence of lung cancer continues to rise. New methods are being developed to aid in the early detection and localization of lung cancer in hopes that overall survival can be improved. More accurate staging may prevent patients who have advanced disease from encountering the morbidity associated with thoracotomy. This review summarizes some of the new methods being evaluated to assist in the early diagnosis and staging of bronchogenic carcinoma.

Extrapulmonary lymphangioleiomyomatosis and lymphangiomatous cysts in tuberous sclerosis complex

OBJECTIVE

To describe the clinical manifestations, imaging findings, and histologic features of extrapulmonary lymphangioleiomyomatosis (LAM) in the tuberous sclerosis complex (TSC).

DESIGN

We retrospectively reviewed institutional medical records since 1940 to identify patients with TSC and extrapulmonary LAM.

MATERIAL AND METHODS

Of 403 patients with TSC, 3 had pulmonary and extrapulmonary LAM and retroperitoneal lymphangiomatous cysts. The clinical, imaging, and histologic features of these three patients were summarized, including analysis of biopsy specimens by conventional histology, immunohistology, radiolabeled ligand-binding assays, and tissue culture.

RESULTS

The three young women had characteristic dermatologic findings of TSC and pulmonary LAM. Two patients were of normal intelligence, and one had a recent history of contraceptive use. All three patients had intra-abdominal lymphangiomatous cysts, uterine LAM, and renal angiomyolipomas. Renal and uterine biopsy specimens demonstrated positive immunostaining for melanoma-related antigens and expression of estrogen and progesterone receptors by ligand-binding assay and immunohistology. Cells cultured from LAM tissue of one of the patients exhibited a mitogenic response to estradiol.

CONCLUSION

Clinically significant extrapulmonary LAM is a rare manifestation of TSC and may occur in women with this disease who also have pulmonary LAM. The clinical features of these patients confirm the importance of sex steroids in the development of these lesions. Immunohistochemical findings suggest that LAM and angiomyolipomas have a neuroectodermal origin. The development of lymphangiomatous cysts in these patients is probably due to smooth muscle proliferation in lymph vessels, which can result in lymphatic obstruction.

Tracheobronchial involvement in Wegener's granulomatosis

This study was designed to characterize the clinical spectrum and course of tracheobronchial involvement in Wegener's granulomatosis (WG). Of the 51 patients with biopsy-proven WG who underwent bronchoscopy at least once at our institution between January 1982 and November 1993, 30 (59%) had endobronchial abnormalities due to WG. Initial findings included subglottic stenosis in five (17%), ulcerating tracheobronchitis with or without inflammatory pseudotumors in 18 (60%), tracheal or bronchial stenosis without inflammation in four (13%), and hemorrhage without identifiable source in two (4%) patients. Nine patients with ulcerating tracheobronchitis on initial study had subsequent bronchoscopies for continued symptoms, which in seven cases documented the progression from ulcerating tracheobronchitis to stenosis without inflammation. Bronchoscopic interventions included dilation by rigid bronchoscope in three, YAG-laser treatment in one, and placement of silastic airway stents in three patients. Only the stents provided persistent airway patency. Endobronchial biopsies were performed on 21 occasions in 17 patients. Half of the specimens were helpful in establishing the diagnosis and in all but three in assessing disease activity. While antineutrophil cytoplasmic antibody titers reflect overall disease activity, no correlation with endobronchial inflammatory activity was apparent.

The role of transcarinal needle aspiration in the staging of bronchogenic carcinoma

Metastatic spread to subcarinal lymph nodes in patients with bronchogenic carcinoma generally indicates unresectability. Transcarinal needle aspiration of the main carina (TCNA) has been used to obviate the need for more invasive procedures, particularly thoracic surgery. Of 510 transbronchial needle aspirations performed at our institution from 1983 to 1991, 88 (17 percent) were from the main carina in patients with bronchogenic carcinoma. We reviewed these 88 TCNA procedures to assess our experience with TCNA in the staging of lung cancer. The TCNA results were positive in 32 of 88 (36 percent) patients (20 non-small-cell cancers, 12 small-cell lung cancers). Following bronchoscopy, TCNA was the only evidence of unresectability in all 20 patients with non-small-cell lung cancer and was the only mode of diagnosis in 5 of 12 (42 percent) patients with small-cell lung cancer. Thirteen patients with non-small-cell lung cancer and positive TCNA also had positive bronchial secretion cytologic studies. Five of these patients had further subcarinal sampling and in all cases metastatic involvement was confirmed. TCNA was positive in 29 of 67 (43 percent) patients with radiographic evidence of mediastinal adenopathy. Of the remaining 38 patients with radiographic evidence of mediastinal adenopathy and negative TCNA results, 23 patients had further mediastinal sampling with mediastinoscopy or thoracotomy and in all cases mediastinal spread of cancer was established. Nineteen of 58 (33 percent) patients with an endoscopically normal-appearing main carina had a positive TCNA, while 13 of 30 (43 percent) patients with broadening or widening of the main carina had positive TCNA results. There were no complications. We conclude that TCNA is often a safe and useful staging modality in patients with bronchogenic carcinoma.

Ancillary therapies in the management of lung cancer: photodynamic therapy, laser therapy, and endobronchial prosthetic devices

Endoscopic therapy for cancer that involves the tracheobronchial tree is currently available for two distinct types of lesions: radiographically occult superficial squamous cell carcinoma and advanced malignant tumors that cause severe airway obstruction. Photodynamic therapy, which uses a photosensitizing agent, is effective for managing early superficial squamous cell carcinoma. Neodymium:yttrium-aluminum-garnet laser therapy has been effective in the palliative management of patients with advanced or recurrent malignant obstructive airway lesions, either alone or in combination with intraluminal radiation therapy. Most recently, endobronchial prosthetic devices (stents) have been used in patients with advanced airway obstruction. The use of each of these modalities in the management of lung cancer is reviewed.

Photodynamic therapy in the management of early superficial squamous cell carcinoma as an alternative to surgical resection

Photodynamic therapy has been used since 1980 at our institution for the management of cancer of the tracheobronchial tree. We identified 13 patients (14 cancers) who were thought to be surgical candidates but who elected to have photodynamic therapy. Thirteen cancers (93 percent) had a complete response to hematoporphyrin-derivative phototherapy. Ten cancers (71 percent) showed a complete response after single treatment, and three (21 percent) required a second course of therapy to achieve a complete response. Ten (77 percent) of 13 cancers have shown no local recurrence. Three patients with persistent cancer underwent surgical resection and were found not to have nodal involvement. We concluded that photodynamic therapy is an alternative to surgical resection in the management of early superficial squamous cell carcinoma.

Endothelium-derived relaxing factor in pulmonary and renal circulations during hypoxia

The pulmonary and renal vasculatures, in contrast to the systemic vasculature, constrict during hypoxia. The endothelium has been implicated in mediating these vascular responses to acute hypoxia via the production of endothelium-derived vasoactive factors. The present study, performed in anesthetized dogs, was designed to investigate the role of endothelium-derived relaxing factor (EDRF) to attenuate the vasoconstrictor response of the pulmonary and renal circulations during acute hypoxia. In response to hypoxia, pulmonary (2.2 +/- 0.3 to 4.5 +/- 0.6 mmHg.l-1.min) and renal (0.60 +/- 0.07 to 0.90 +/- 0.14 mmHg.ml-1.min) vascular resistances increased. Inhibition of endogenous EDRF with NG-monomethyl-L-arginine resulted in similar increases in pulmonary (3.0 +/- 0.1 to 4.8 +/- 0.4 mmHg.l-1.min) and renal (0.67 +/- 0.07 to 0.90 +/- 0.09 mmHg.ml-1.min) vascular resistances as in hypoxia. However, in the presence of both hypoxia and EDRF inhibition, an exaggerated pulmonary vascular response was observed (2.2 +/- 0.2 to 7.4 +/- 0.9 mmHg.l-1.min), in contrast to the renal vascular response to EDRF inhibition during hypoxia (0.61 +/- 0.05 to 0.95 +/- 0.10 mmHg.ml-1.min), which was not different from hypoxia or EDRF inhibition individually. The endothelium-derived contracting factor endothelin, which modestly increased during hypoxia (11.7 +/- 1.9 to 15.6 +/- 2.4 pg/ml), may also contribute to this vasoconstrictive response to hypoxia. This study suggests in the intact animal that EDRF serves to oppose the pulmonary vasoconstrictor response to hypoxia and further characterizes the role of endothelium-derived factors in the regulation of vascular function during hypoxia.

Primary biliary cirrhosis: relation between hepatic function and pulmonary function in patients who never smoked

We studied the relationship between selected variables of hepatic and pulmonary function in 47 patients with primary biliary cirrhosis, who were participating in a prospective study to assess sequential pulmonary function at yearly intervals. An additional 20 patients with primary biliary cirrhosis, who were liver transplant candidates awaiting transplantation, were studied. None of the 67 patients ever smoked cigarettes. Severity of primary biliary cirrhosis was characterized by histological stage and the Mayo risk score derived from a Cox regression model that used the following variables: serum bilirubin and serum albumin levels, age, prothrombin time and clinical severity of edema. Pulmonary function assessment included key variables describing expiratory airflow (forced expiratory volume in 1 sec divided by forced vital capacity) and efficiency of gas exchange (steady-state diffusing capacity for carbon monoxide). We found a significant relationship between histological stage of primary biliary cirrhosis and steady-state diffusing capacity (p = 0.02) and between the Mayo risk score for disease severity and steady-state diffusing capacity (p = 0.03). Progressive deterioration of steady-state diffusing capacity was associated with increasing severity of primary biliary cirrhosis. No relationship existed between pulmonary function and the presence of sicca complex or Sjögren's syndrome or the clinical manifestations of portal hypertension (e.g., esophageal varices, ascites and splenomegaly). No significant relationship existed between expiratory airflow and severity of primary biliary cirrhosis. We conclude that in patients with primary biliary cirrhosis who have never smoked, a statistically significant relationship exists between the severity of the liver disease and the efficiency of gas exchange measured by steady-state diffusing capacity.(ABSTRACT TRUNCATED AT 250 WORDS)

Tracheobronchopathia osteochondroplastica

Tracheobronchopathia osteochondroplastica is an unusual disease of obscure causation characterized by cartilaginous or bony outgrowths into the lumen of the tracheobronchial tree. Our retrospective review of 15 patients, 8 of whom were women, revealed a mean age of 63.5 years. The most common symptoms were cough (66%), hemoptysis (60%), dyspnea on exertion (53%), and wheeze (30%). Thirteen percent of the patients were asymptomatic. Chest radiography was not helpful in the diagnosis. Tracheal tomography revealed typical beaded intraluminal calcification in 4 of the 12 patients tested. Mirror laryngoscopy initially revealed the abnormalities in 30% of the patients, and bronchoscopy confirmed the diagnosis and determined the extent of the disease in all patients. Even though upper airway involvement has been thought to be uncommon, 40% of our patients demonstrated abnormalities of the larynx and upper trachea. Histologic confirmation of heterotopic bone formation was obtained in 60% of the patients. Pulmonary function tests showed mild obstructive lung disease. There were no deaths directly attributable to the disease. Treatments attempted included cryotherapy, laser excision, external beam irradiation, and bronchoscopic removal of the obstructing lesions.

The assessment of major airway function in a ventilator-dependent patient with tracheomalacia

A 60-pack-year smoker presented with cough, dyspnea and orthopnea of three months' duration. Spirometry revealed severe reduction in maximal expiratory flow; CT of the chest and bronchoscopy demonstrated expiratory collapse of a mid-tracheal segment, and a presumptive diagnosis of tracheomalacia was made. A right lateral thoracotomy was performed to resect the unstable segment and improve maximal expiratory flow. Diffuse major airway disease with absence of cartilaginous rings from the thoracic inlet to the mainstem bronchi was encountered. The trachea and mainstem bronchi were stented externally. A high resistance to airflow and absence of expiratory flow limitation were present, suggesting a fixed rather than variable intrathoracic obstruction of major airways. This case illustrates some potential pitfalls in preoperative assessment of patients with tracheomalacia. Recordings of airway pressure and flow during mechanical ventilation are useful in distinguishing between fixed and variable intrathoracic obstruction and may complement tests of airway anatomy.

Severe hypoxemia and liver disease

Severe hypoxemia and orthodeoxia in patients with chronic liver disease is uncommon, but, when present, it is incapacitating. The purpose of this study was to determine the distribution of alveolar ventilation-perfusion (VA/Q) in six patients with mild liver disease and severe hypoxemia (PaO2 at rest in sitting or standing position ranged from 35 to 67 mm Hg). Orthodeoxia was documented with improvement in PaO2 in the supine position in each patient (PaO2 at rest in supine position ranged from 46 to 75 mm Hg). VA/Q distribution was measured by the multiple inert gas elimination technique. The dispersion of VA/Q was increased with small portions of the cardiac output (0.5 to 14.8%) perfusing low VA/Q areas (O less than VA/Q less than 0.1). Another major finding was a large right-to-left shunt (VA/Q less than 0.005) that ranged from 4 to 28%. The VA/Q mismatching and the right-to-left shunt both contributed to the hypoxemia. The predicted PaO2 was 5.5 mm Hg (p less than 0.01) larger than the measured PaO2. In each patient, the mean pulmonary artery pressure was low and the cardiac output was elevated. These results show that the low PaO2 in these patients was due to both increased right-to-left shunt and VA/Q mismatching, but impaired diffusion could not be ruled out.

Bronchoscopic localization and treatment of occult lung cancer

The flexible fiberoptic bronchoscope is currently the standard tool for localization of radiographically occult carcinomas of the tracheobronchial tree. It allows direct inspection of proximal airways and can establish the location of most occult lung cancers. A small percentage of patients present with bronchoscopically as well as radiographically occult carcinoma, particularly challenging because definitive localizations is required before a therapeutic plan can be outlined. Selective cytologic brushing of each lobar segment, taking random biopsy specimens, has been used to assist in localization of these early cancers. Recently, fluorescent compounds have been used to assist in localizing early lung cancers and in the treatment of radiographically occult carcinoma. We review the current methods of bronchoscopic localization and treatment of radiographically occult lung cancer.

Tracheopathia osteoplastica: familial occurrence

Tracheopathia osteoplastica is an unusual disease characterized by cartilaginous or bony projections into the tracheobronchial lumen, with sparing of the posterior membranous portion of the tracheobronchial tree. The cause of this disorder is unknown. The diagnosis is seldom made because of the chronic and asymptomatic nature of the condition. More than 90% of the cases are diagnosed at postmortem examination. Symptoms may include dyspnea, coughing, hemoptysis, hoarseness, and wheezing. Tomography of the trachea may reveal beaded calcification of the tracheobronchial cartilages. Bronchoscopy is diagnostic. Histologically, the abnormal growths show heterotopic bone formation. No known treatment is available. We describe two female patients, one with hemoptysis and another with asthmalike symptoms, in both of whom bronchoscopy established the diagnosis of tracheopathia osteoplastica. The first patient had recurrent episodes of pneumonia attributable to bronchial obstruction by bony projections. In the second patient, removal of large lesions that obstructed the upper part of the trachea relieved the dyspnea. Of interest is the fact that the first patient was the biologic mother of the second. To our knowledge, this constitutes the first report of familial occurrence of tracheopathia osteoplastica.

Combined effects of hematoporphyrin derivative phototherapy and adriamycin in a murine tumor model

Hematoporphyrin derivative phototherapy (HpD-PT) is currently being used experimentally in the treatment of various malignancies. The effectiveness of HpD-PT appears to be limited to superficial malignancies because of its inability to penetrate more than 0.5-1 cm. The mechanism of action has been demonstrated to result from the formation of toxic singlet oxygen and other oxygen radicals. Preliminary work suggested that the addition of other chemical agents known to produce toxic oxygen radicals may enhance the effect of HpD-PT. To test this hypothesis, we examined the effectiveness of HpD-PT in the Walker 256 carcinosarcoma with and without Adriamycin. Tumor kill was estimated by calculating the area of necrosis on photomicrographic sections. From this area, a radius of tumor necrosis was determined and compared among various control and experimental groups. HpD-PT was effective in this model when compared to control groups (radius of necrosis 3.79 +/- 0.97 mm vs. 2.60 +/- 1.26 mm, P less than .05). The addition of Adriamycin significantly increased the radius of necrosis when compared to HpD-PT (4.57 +/- 1.70 mm vs. 3.69 +/- 0.97 mm, P less than .01). From this work we conclude that HpD-PT demonstrates effective tumor killing in this murine model. The addition of Adriamycin significantly increased tumor kill.

Bronchoscopic phototherapy with hematoporphyrin derivative for treatment of localized bronchogenic carcinoma: a 5-year experience

Between December 1980 and April 1986 at our institution, 38 patients with cancer that involved the tracheobronchial tree (a total of 40 carcinomas) completed at least one course of hematoporphyrin derivative phototherapy. A complete response occurred in 13 patients (with 14 carcinomas). Eleven of these carcinomas did not recur during follow-up periods that ranged from 3 to 53 months. Three carcinomas recurred at 9, 12, and 35 months, respectively. For 26 carcinomas, the response was less than complete, and alternative therapy was necessary. The carcinomas in patients with a complete response were radiographically occult, were less than 3 cm2 in surface area, and appeared superficial at bronchoscopy. Our experience supports the use of hematoporphyrin derivative phototherapy as an alternative to surgical resection in carefully selected patients.