Experimental use of an illuminated and magnetic tip, flow-directed pulmonary artery catheter for lung resection.

The authors performed a study to design and evaluate a device giving the surgeon added protection against pulmonary artery injury in a closed thoracic compartment. Eleven swine were used for a total of 12 lobectomies. A light-bearing, magnetic-tipped, modified Swan-Ganz catheter was passed through the jugular vein into the left pulmonary artery. By using magnetic guidance through a port site and balloon inflation, cessation of flow in the pulmonary artery was documented by Doppler. Twelve video-assisted lobectomies were performed. Nine of 12 (75%) lobectomies were completed successfully by using the magnetic-tipped, illuminated balloon catheter. In 4 cases, the catheter displaced because of the short left main pulmonary artery in swine. In one case, the balloon was recovered, and successful lobectomy was performed. The use of a magnetic-tipped, flow-directed device may provide an effective means of endovascular control during thoracoscopic pulmonary arterial dissection.

Glutathione S-transferase-catalyzed conjugation of bioactivated aflatoxin B(1) in human lung: differential cellular distribution and lack of significance of the GSTM1 genetic polymorphism.

Epidemiological studies suggest that aflatoxin B(1) (AFB(1)), a mycotoxin produced by certain Aspergillus species, may play a role in human respiratory cancers in occupationally-exposed individuals. AFB(1) requires bioactivation to the corresponding exo-8,9-epoxide for carcinogenicity, and glutathione S-transferase (GST)-catalyzed conjugation of the epoxide with glutathione (GSH) is a critical determinant of susceptibility to AFB(1). Of the purified human GST enzymes studied, the polymorphic hGSTM1-1 has the highest activity towards AFB(1) exo-epoxide. The influence of the GSTM1 polymorphism on AFB(1)-GSH formation, as well as the abilities of cytosols from preparations enriched in different isolated lung cell types to conjugate AFB(1)-epoxides, were examined. In whole-lung cytosols from patients undergoing clinically indicated lobectomy, GSTM1 genotype correlated with GSTM1 phenotype as determined by [(3)H]trans-stilbene oxide conjugation: GSTM1-positive = 295 +/- 31 pmol/mg/h (n = 6); GSTM1-negative = 92.8 +/- 23.3 pmol/mg/h (n = 4) (P < 0.05). In contrast, conjugation of microsome-generated [(3)H]AFB(1)-epoxides with GSH was low and variable between patients, and did not correlate with GSTM1 genotype: GSTM1-positive = 11.9 +/- 8.1, 111 +/- 66 and 510 +/- 248 fmol/mg/h (n = 6); GSTM1-negative = 15.3 +/- 16.7, 167 +/- 225 and 540 +/- 618 fmol/mg/h (n = 4) (for 1, 10 and 100 microM [(3)H]AFB(1), respectively). GSH conjugates of AFB(1) exo-epoxide and the much less mutagenic stereoisomer AFB(1) endo-epoxide were produced in a ratio of approximately 1:1 in cytosols from both whole lung and isolated cells. Total cytosolic AFB(1)-epoxide conjugation was significantly higher in fractions enriched in alveolar type II cells (3.07 +/- 1.61 pmol/mg/h) than in unseparated lung cells (0.143 +/- 0.055 pmol/mg/h) or fractions enriched in alveolar macrophages (0. 904 +/- 0.319 pmol/mg/h; n = 4) (P < 0.05). Furthermore, AFB(1)-GSH formation and percentage of alveolar type II cells in different cell fractions were correlated (r = 0.78, P < 0.05). These results demonstrate that human lung GSTs exhibit very low conjugation activity for both AFB(1)-8,9-epoxide stereoisomers, and that this activity is heterogeneously distributed among cell types, with alveolar type II cells exhibiting relatively high activity. Of the GSTs present in human peripheral lung which contribute to AFB(1) exo- and endo-epoxide detoxification, hGSTM1-1 appears to play at most only a minor role.

Indications for pneumonectomy. Pneumonectomy for benign disease.

A wide variety of nonmalignant diseases of the lung require pneumonectomy. Pneumonectomy for inflammatory lung disease is frequently associated with high morbidity rates, and the frequencies of postpneumonectomy space empyema and bronchopleural fistula are high. It is essential to treat underlying infections prior to surgery in an effort to minimize the sputum production, maximize the patient's nutritional status, minimize the chance for intraoperative spillage, and decrease the risk of postoperative bronchopleural fistulas and postpneumonectomy space empyemas. Despite the challenges of performing a pneumonectomy for inflammatory diseases, cure rates for MDR-TB, MOTT infections, and fungal disease, including invasive fungal disease, are excellent. Pneumonectomy for trauma is associated with very high mortality, and efforts should be made to avoid pneumonectomy if possible. Pneumonectomy for other benign conditions is unusual.

Perforation of the right ventricle: a complication of blind placement of a chest tube into the postpneumonectomy space.

We were asked to review a case from an outside hospital in which there was inadvertent perforation of the right ventricle during the percutaneous placement of a chest tube. We present the case in the hopes that by doing so, others will avoid such a complication in the future. After reviewing the case, it appeared that the complication occurred because the physician was not knowledgeable about the anatomy of the postpneumonectomy space and the physician failed to use the safest procedure in placing the tube.

Thoracoscopic lobectomy with endoarterial vascular control: an experimental study in swine.

BACKGROUND: Video-assisted lobectomy lacks vascular control and presents the potential for serious hemorrhage in a closed cavity. The use of a lighted, flow-directed balloon catheter in the pulmonary artery as an endovascular control device was evaluated. METHODS: A modified light-bearing Swan-Ganz catheter was placed in the left or right pulmonary artery using fluoroscopy. The lit catheter was identified easily through the arterial wall at thoracoscopy. Its inflation allowed the control of proximal blood flow as required. Fully thoracoscopic lobectomy was carried out by isolating and dividing the lobar branches of the pulmonary artery, the pulmonary vein, and the bronchus in anesthetized swine. RESULTS: Forty-two video-assisted anatomic lobectomies were completed in 30 pigs with balloon catheter control of the pulmonary artery. The balloon effectively controlled experimental hemorrhage caused by puncturing arterial branches (n = 4). It allowed the transection of unlooped lobar arteries (n = 42) and the main interlobar pulmonary artery (n = 3). Catheter displacement back to the heart occurred in 5 animals and balloon catheter technical failures occurred in 3. CONCLUSIONS: The lighted, flow-directed balloon catheter was an effective means of avoiding acute hemorrhage and achieving vascular control in a swine lobectomy model.

Acute submucosal esophageal hemorrhage.

Two cases of acute submucosal esophageal hemorrhage are reported. This condition is uncommon and presents an urgent diagnostic dilemma. Its presentation, diagnosis, and management are reviewed. The underlying pathology and causative factors are researched and clarified. Conservative management is safe and effective.

Biotransformation of aflatoxin B1 in human lung.

In addition to being a potent hepatocarcinogen, aflatoxin B1 (AFB1) is a pulmonary carcinogen in experimental animals, and epidemiological studies have shown an association between AFB1 exposure and lung cancer in humans. This study investigated AFB1 bioactivation and detoxification in human lung tissue obtained from patients undergoing clinically indicated lobectomy. [3H]AFB1 was bioactivated to a DNA binding metabolite by human whole lung cytosols in a time-, protein concentration-, and AFB1 concentration-dependent manner. Cytosolic activation of [3H]AFB1 correlated with lipoxygenase (LOX) activity and was inhibited by the LOX inhibitor nordihydroguaiaretic acid (NDGA; 100 microM), indicating that LOXs were largely responsible for the observed cytosolic activation of AFB1. In whole lung microsomes, low levels of indomethacin inhibitable prostaglandin H synthase (PHS)-mediated [3H]AFB1-DNA binding and cytochrome P-450 (P450)-mediated [3H]AFB1-DNA binding were observed. Cytosolic glutathione S-transferase (GST)-catalyzed detoxification of AFB1-8,9-epoxide, produced by rabbit liver microsomes, was minimal at 1 and 10 microM [3H]AFB1. With 100 microM [3H]AFB1, [3H]AFB1-8,9-epoxide conjugation with reduced glutathione was 0.34 +/- 0.26 pmol/mg/h (n = 10). In intact, isolated human lung cells, [3H]AFB1 binding to cellular DNA was higher in cell fractions enriched in macrophages than in either type II cell-enriched fractions or fractions containing unseparated cell types. Indomethacin produced a 63-100% decrease in [3H]AFB1-DNA binding in macrophages from five of seven patients, while NDGA inhibited [3H]AFB1-DNA adduct formation by 19, 40 and 56% in macrophages from three of seven patients. In alveolar type II cells, NDGA decreased [3H]AFB1-DNA binding by 30-100% in cells from three patients and indomethacin had little effect. SKF525A, an isozyme non-selective P450 inhibitor, enhanced [3H]AFB1 binding to cellular DNA in unseparated cells, macrophages, and type II cells, suggesting that P450-mediated bioactivation of AFB1 is not a major pathway by which AFB1-8,9-epoxide is formed in human lung cells. Overall, these studies suggest that P450 has a minor role in the bioactivation of AFB1 in human lung. Rather, LOXs and PHS appear to be important bioactivation enzymes. Co-oxidative bioactivation of AFB1, in combination with the low conjugating activity displayed by human lung cytosolic GSTs, likely contributes to human pulmonary susceptibility to AFB1.

Mechanisms of relief of exertional breathlessness following unilateral bullectomy and lung volume reduction surgery in emphysema.

STUDY OBJECTIVE: To explore mechanisms of relief of exertional breathlessness following surgery to reduce thoracic gas volume in patients with emphysema. MATERIALS AND METHODS: We studied 8 patients with emphysema (FEV1 = 39 +/- 3% predicted; residual volume [RV] = 234 +/- 12% predicted; mean +/- SEM) who were severely breathless despite optimal pharmacotherapy and who underwent unilateral bullectomy for giant bullae (greater than one third hemithorax); 4 of these also had ipsilateral lung reduction (pneumectomy). Pulmonary function and cycle exercise performance (n = 6) were evaluated before and 13 +/- 3 weeks after surgery. Chronic breathlessness was measured with the Baseline Dyspnea Index and the Medical Research Council dyspnea scale. Exertional breathlessness was measured using Borg ratings at a standardized work rate (BorgSTD). RESULTS: FEV1, FVC, and maximal inspiratory pressures increased postsurgery by 29 +/- 7% (p < 0.05), 24 +/- 10% (p = 0.06), and 39 +/- 12% (p < 0.01), respectively. Plethysmographic total lung capacity, RV, and functional residual capacity fell by 14 +/- 2%, 30 +/- 4%, and 18 +/- 3%, respectively (p < 0.001). All measures of chronic breathlessness improved significantly (p < 0.05). During exercise at a standardized work rate, BorgSTD fell 45% (p < 0.05), end-expiratory lung volume (EELV) fell 22% (p < 0.01), and breathing frequency (F) fell 25% (p = 0.08). By multiple stepwise regression analysis, 99% (p = 0.007) of the variance in symptom relief (delta BorgSTD) was explained by the combination of decreased ratio of the end-expiratory lung volume to total lung capacity, decreased F, and diminished mechanical constraints on tidal volume (tidal volume to vital capacity ratio). CONCLUSION: Reduced exertional breathlessness at a given workload after volume reduction surgery was attributed to a combination of reduced thoracic hyperinflation, reduced F, and reduced mechanical constraints on lung volume expansion.

Left hilar mass with obstruction of the main bronchus due to localized pseudoaneurysm of the thoracic aorta.

The left hilum is an anatomically complex region. It is poorly imaged on conventional chest roentgenography and even on tomography. A wide range of diagnoses must be considered upon discovery of a hilar mass. In this report, the authors discuss their experience with a potentially hazardous hilar mass found in a 61-year-old man with a 40 pack-year smoking history. The mass, which was identified as an aortic pseudoaneurysm, caused near-total obstruction of the left main bronchus. The aneurysm was successfully repaired and patency of the bronchus restored. Radiographic features that suggest an aortic aneurysm as a cause of a hilar mass include posterior location and lack of associated mediastinal or contralateral hilar adenopathy. Computer tomography with contrast will readily define a vascular hilar mass. If cancer or lymphoma are suspected as the cause of a hilar mass, mediastinal lymph-node imaging, and aspiration or biopsy are indicated.

Elective pneumonectomy for benign lung disease: modern-day mortality and morbidity.

This retrospective study of elective pneumonectomy for complicated inflammatory lung disease was done to define modern-day mortality and morbidity. One hundred twenty-four patients received elective pneumonectomy. Patient ages ranged from 6 months to 71 years. Past, recurrent, or new pulmonary tuberculosis was present in 107 patients (86.3%). Clinical presentation involved recurrent infections or severe suppurative sequelae (abscess, empyema). Forty-seven patients had chronic hemoptysis and 25 patients had past or recent massive hemoptysis (> 600 ml of hemoptysis fluid within 24 hours). Nutritional deficiencies were common. One hundred six patients (85.5%) had end-stage destroyed lungs. Evaluative bronchoscopy showed inflammatory endobronchial changes in 106 patients (85.5%), bronchial strictures in 4, and indolent endobronchial tumor in 2. Lung separation was by double-lumen tube in 96 patients, single lung-single tube in 6, bronchus blocker in 6, and prone posture in 9. Extrapleural pneumonectomy was done in 83 patients (66.9%). Fifty-seven of these procedures were left sided and 26 were right sided. Standard transpleural pneumonectomy was done in 41 patients (33.1%): 30 left sided and 11 right sided. Nine pneumonectomies were conducted with the patient in the prone position. Four patients had completion pneumonectomy. Hospital mortality was three deaths (2.4%). Morbidity included postpneumonectomy empyema in 19 patients (15.3%). Seven postoperative bronchopleural fistulas occurred. Empyema in most patients was managed by open pleural drainage (thoracostoma) and later space closure. Pneumonectomy proved effective therapy with low mortality but postpneumonectomy empyema posed serious morbidity.

Unusual site of spontaneous first-rib fracture: case report.

Spontaneous fractures of the first rib are uncommon and are usually thought to be associated with a malignant process. However, fatigue fractures of the first rib are being encountered increasingly in association with various physical activities. Typically, the fractures occur at the subclavian groove, but in the 48-year-old woman described in this report the fracture was unexpectedly situated in the posterior portion of the rib and was the result of snow shovelling, which was a new activity for the patient.

Intraoperative whole-lung torsion producing pulmonary venous infarction.

Pulmonary venous infarction and whole-lung torsion are both rare, life-threatening complications of thoracic operations. A case of whole-lung torsion with resultant pulmonary venous infarction of the entire lung after a nonpulmonary thoracic operation is reported.

Surgical management of the redundant transposed colon.

Redundancy of the transposed thoracic colon is not uncommon. Rarely, however, when accompanied by severe symptoms, it may necessitate surgical correction. We describe herein a surgical technique that allows the stretching and straightening of the redundant transposed organ.

Pulmonary aspergilloma--indications for surgical intervention. An analysis of 22 cases.

Surgical resection of aspergillomas has generally been associated with excess mortality and morbidity; 22 patients who had a resection of complicated mycetomas were studied retrospectively. Indications for surgery were serious haemoptysis (14), massive haemoptysis (6), and recurrent infection (2). Extrapleural pneumonectomy was required in 9 patients and extrapleural lobectomy in 12; thoracoplasty alone was done in 1 patient. There was 1 hospital death (4.5%); 4 patients developed postoperative empyemas (18%), 2 with associated bronchopleural fistulas. Two further patients (9%) had stable postresectional spaces. Surgery for complicated aspergilloma was associated with significant postoperative morbidity.