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A F Gelb

Publications and source records attributed to A F Gelb.

At least 37 records · Page 2Linked to original sources

Contribution of lung and chest wall mechanics following emphysema resection.

OBJECTIVE: To determine the contributions of (1) chest wall (Pcw) and (2) lung elastic recoil pressure (PL) to (3) total elastic recoil pressure exerted by the respiratory system (Prs) in 18 patients (12 men) aged 66 +/- 6 years (mean +/- 1 SD) with severe emphysema who underwent video-assisted thoracoscopic bilateral lung volume reduction surgery under paralyzed (vecuronium) general anesthesia (isoflurane). DESIGN: We measured preoperative and 6-week postoperative lung function studies, and intraoperative inspiratory lung conductance (GL), PL, Pcw, and Prs (cm H2O) at end-expiratory lung volume (EELV), EELV plus 0.60 +/- 0.0 L, and EELV plus 1.15 +/- 0.0 L. All values are mean +/- SEM. RESULTS: Preoperative vs postoperative FVC was 1.9 +/- 0.1 L vs 2.3 +/- 0.1 L (p = 0.03); FEV1 was 0.6 +/- 0.1 L vs 0.9 +/- 0.1 L (p < 0.02); total lung capacity was 7.4 +/- 0.4 L vs 5.9 +/- 0.3 L (p < 0.001); functional residual capacity was 5.7 +/- 0.4 L vs 4.4 +/- 0.2 L (p = 0.001). At EELV preoperative vs postoperative, PL was 0.0 +/- 0.3 vs 1.1 +/- 0.05 (p = 0.04), Pcw was 5.0 +/- 0.7 vs 2.4 +/- 0.9 (p = 0.02), and Prs was 5.0 +/- 0.8 vs 3.5 +/- 0.7 (p = 0.08). AT EELV plus 0.60 L, PL was 3.2 +/- 0.6 vs 6.1 +/- 0.9 (p < 0.001), Pcw was 8.8 +/- 0.8 vs 7.0 +/- 0.9 (p = 0.12), and Prs was 12.0 +/- 0.8 vs 13.1 +/- 0.7 (p = 0.80). At EELV plus 1.15 L, PL was 6.8 +/- 0.9 vs 10.3 +/- 1.1 (p < 0.001), Pcw was 13.5 +/- 1.0 vs 11.2 +/- 1.2 (p = 0.12), and Prs was 20 +/- 1.2 vs 21.5 +/- 1.0 p = 0.93). AT EELV plus 0.06 L, GL was 0.09 +/- 0.00 L/S/cm H2O vs 0.16 +/- 0.01 (p < 0.01). At EELV plus 1.15 L, GL was 0.12 +/- 0.01 vs 0.21 +/- 0.03 (p < 0.05) with similar preoperative vs postoperative GL/PL slopes. CONCLUSION: The increase in PL and decrease in Pcw following LVRS for emphysema may be responsible for the increase in spirometry and airway conductance.

Aged↗

Lung volume reduction surgery for emphysema.

There has been dramatic resurgence of interest in surgical treatment of emphysema, particularly "lung volume reduction" procedures. Recent studies have demonstrated improvements in pulmonary function, lung mechanics, exercise tolerance, and quality of life in selected patients following volume reduction procedures. However, considerable uncertainty remains regarding overall benefit, optimal patient selection, operative techniques, and duration of response. This summarizes current approaches to lung volume reduction surgery, available clinical outcome information, selection criteria, and physiologic mechanisms of response, and discusses the potential role for surgical volume reduction in treatment of emphysema. Recent data appear to support the efficacy of bilateral staple lung volume reduction surgery in patients with severe symptomatic heterogeneously distributed emphysema. Further studies will be needed to determine relative value of different operative techniques and benefit in patients with other clinical presentations.

Algorithms↗

Combined operations for lung volume reduction surgery and lung cancer.

Fifty-three lung masses were found in 51 (16%) of 325 patients who underwent lung volume reduction surgery. This included 11 non-small cell lung cancers and 42 benign lung masses. Eleven patients (mean age, 69.4 years) underwent a combined lung volume reduction surgery and resection of clinical stage I lung cancers (lymph node dissection with either lobectomy [3] or wedge resection [8]). There were no deaths or major complications. The average length of stay was 8.7 days. The mean FEV1 was 654 mL (21.7% predicted) preoperatively and 1,079 mL (49% predicted) postoperatively. Patients who are screened for lung volume reduction surgery should be carefully evaluated for possible lung masses. Lung volume reduction surgery allows lung cancer surgery in patients who otherwise would be considered to have physiologically inoperable disease.

Aged↗

Lung function 12 months following emphysema resection.

OBJECTIVE: To investigate the mechanism of airflow limitation before and 6 and 12 months after targeted emphysematous resection in 10 male patients aged 67 +/- 8 years (mean +/- SD) with very severe COPD undergoing bilateral thoracoscopic stapling techniques. DESIGN: Lung function, including static lung elastic recoil, was measured 2 weeks before and 6 and 12 months after surgery. RESULTS: Twelve months after surgery, there was a significant (p < 0.001) reduction in total lung capacity (TLC), 9.5 +/- 0.3 L (mean +/- SEM) to 8.5 +/- 0.3 L, functional residual capacity, and residual volume. Airway conductance and FEV1, 0.71 +/- 0.1 L (mean +/- SEM) to 0.95 +/- 0.1 L, improved significantly (p < 0.01). Lung elastic recoil increased markedly at TLC from 11.7 +/- 0.7 cm H2O (mean +/- SEM) to 15.0 +/- 1.0 cm H2O (p < 0.01) as did maximum expiratory airflow in every patient. However, when compared with data obtained in each patient at 6 months, lung volumes are significantly increased, and expiratory airflow and lung elastic recoil pressures are significantly reduced (p < or = 0.05). Analysis of maximum expiratory flow-static elastic recoil pressure curve indicates conductance of the S airway segment (Gs) increased from 0.20 +/- 0.03 L/s/cm H2O (mean +/- SEM) to 0.28 +/- 0.04 L/s/cm H2O (p < 0.02), and critical transmural pressure in the collapsible segment (Ptm') decreased from 3.2 +/- 0.2 cm H2O (mean +/- SEM) to 2.5 +/- 0.2 cm H2O (p < 0.01). CONCLUSION: The improvement in maximal expiratory airflow can be attributed primarily to increased lung elastic recoil and its secondary effect on enlarging airway diameter causing increased airway conductance, increased Gs, and decreased Ptm'. The improvement in lung function and elastic recoil peaks at 6 months.

Aged↗

Limited contribution of emphysema in advanced chronic obstructive pulmonary disease.

Previous studies on autopsy specimens or surgically resected lobes or lungs have reached varying conclusions regarding the importance of small airways disease and emphysema in causing fixed expiratory airflow limitation in patients with chronic obstructive pulmonary disease (COPD). We obtained high resolution CT scans of the lung and lung function in 56 consecutive patients with fixed expiratory airflow limitation. There was poor correlation between CT emphysema score and either FEV1/FVC% (r = -0.36) or FEV1 % predicted (r = -0.20). In only 10 of the 35 patients with FEV1 < 50% predicted, the CT emphysema score was > 40, indicating significant emphysema. A strong negative correlation between diffusing capacity % predicted and diffusing capacity per alveolar volume and CT emphysema score was found only in patients with FEV1 > or = 1 L (r = -0.75, p < 0.0001). Thus, emphysema does not appear to be primarily responsible for expiratory airflow limitation in COPD. A low diffusing capacity may be spuriously misleading in patients with FEV1 < 1 L and no or trivial emphysema.

Aged↗

Physiologic studies of tracheobronchial stents in airway obstruction.

When airway obstruction is due to extraluminal compression and/or dynamic collapse, metal and silicone rubber prosthetic stents may stabilize the affected airway. Through a rigid bronchoscope, we inserted three metal stents in two patients and 18 silicone stents in 15 adult patients with symptomatic tracheobronchial compression and dynamic airway collapse. The underlying cause was malignancy in three patients; benign tracheobronchial malacia in three patients, two of whom refused surgical resection; and tracheobronchial stenosis that developed at the anastomotic site following lung transplantation in 11 patients. Clinical status and lung function studies were analyzed before and after stent insertion. Following stent insertion, airway diameter at least doubled and near normal patency of the affected tracheobronchial tree was achieved in every patient using stents of axial length 4 to 5 cm. The stents were well tolerated clinically, and all patients noted immediate relief of dyspnea. Following stent insertion, the forced vital capacity (FVC) increased from 64 +/- 21% predicted (mean +/- 1 SD) to 73 +/- 19% predicted, p less than 0.1; the forced expiratory volume in 1 s (FEV1) from 49 +/- 25% predicted to 72 +/- 26% predicted, p less than 0.02; the ratio of the FEV1/FVC from 59 +/- 16% to 78 +/- 15%, p less than 0.01; and the maximum flow at 50% expired FVC from 38 +/- 26% predicted to 72 +/- 31% predicted, p less than 0.01.

Adult↗

Computed tomography and bronchoscopy in chest radiographically occult main-stem neoplasm diagnosis and Nd-YAG laser treatment in 8 patients.

We studied 8 adult patients with variable symptoms of cough, dyspnea, stridor, wheezing, or hemoptysis. Fiberoptic bronchoscopy in all showed complete or nearly complete endobronchial obstruction of a main-stem bronchus by neoplasm with a mean bronchial diameter of 1.9 mm +/- 1.6 mm (mean +/- standard deviation). In 4 patients, a lobar bronchus was also completely obstructed. No mass was visible on chest radiographs of any patient; however, computed tomography in each showed main-stem endobronchial obstruction, lobar obstruction (4 instances in 3 patients), and in 6 patients hypoperfusion of the involved lung. Computed tomographic scan showed additional abnormalities that were unsuspected on viewing chest radiographs or at bronchoscopy, including mediastinal adenopathy in 3 patients and an extraluminal tumor component in 4. After therapy with Nd-YAG laser, main-stem airway diameter increased to a mean of 9.6 mm +/- 1.0 mm (P less than .05) and pulmonary functions improved. Results suggest the complementary role of computed tomography and fiberoptic bronchoscopy in the detection and laser-treatment planning of chest radiographically occult severe neoplastic obstruction of the main-stem bronchus.

Bronchial Neoplasms↗

Physiologic characteristics of malignant unilateral main-stem bronchial obstruction. Diagnosis and Nd-YAG laser treatment.

To evaluate the effects of severe, unilateral main-stem malignant bronchial obstruction on airway dynamics, we obtained maximal expiratory flow-volume (MEFV) curves in 11 patients 59 +/- 18 yr of age (mean +/- 1 SD), three with and eight without underlying emphysema, before and after laser therapy (10 patients) or lung resection (one patient). Mean main-stem bronchial diameters before and after treatment were 1.1 +/- 1.3 and 9.0 +/- 0.8 mm, respectively (p less than 0.05). In the three patients with underlying emphysema, MEFV curves showed a diffuse intrathoracic obstructive pattern before and after treatment; in the other eight patients, MEFV curves demonstrated an apparently restrictive pattern, with associated airflow obstruction in four, reversible after laser treatment in three of these four. After treatment, all patients exhibited an increase in FVC with a roughly parallel shift of the MEFV curve and little change in the slope of the descending limb of the MEFV curve: FVC improved from 54 +/- 16 to 86 +/- 13% predicted in patients without emphysema and from 54 +/- 16 to 77 +/- 8% predicted in patients with emphysema, whereas the slope of the descending limb of the MEFV curve between 45 and 55% of FVC changed minimally from 2.0 +/- 0.6 to 1.8 +/- 0.5 s-1 in patients without emphysema and from 0.8 +/- 0.3 to 0.8 +/- 0.1 s-1 in patients with emphysema.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗

Diagnosis and Nd-YAG laser treatment of unsuspected malignant tracheal obstruction.

Thirteen adult patients underwent palliative Nd-YAG laser treatment for relief of severe dyspnea due to malignant endotracheal obstruction. Three of the 13 patients had underlying chronic airflow obstruction (CAO) due to diffuse obstructive pulmonary disease. Despite dyspnea, cough, wheezing, stridor and/or hemoptysis, the diagnosis was delayed because of a normal chest roentgenogram in eight patients and nondiagnostic pulmonary function studies (including maximal expiratory and inspiratory flow-volume loops) in all three patients with CAO and in four of ten patients without CAO. The location of the tumor was extrathoracic in two patients, including one with CAO; intrathoracic in seven patients, including two with CAO; and combined extra- and intrathoracic in four. Tracheal diameter increased from 3.5 +/- 1.0 mm before, and to 9.8 +/- 2.0 mm after single or multiple laser treatments. Increased patency of the trachea after laser surgery was associated with improvement in expiratory and/or inspiratory flow rates and with symptomatic relief in all patients which persisted for 14.1 +/- 8.7 months (range four to 48 months). These results indicate that severe symptomatic narrowing of the extra- and/or intrathoracic trachea to a diameter of 2 to 5 mm may not be detected by conventional chest radiography or even by sensitive physiologic tests, especially in patients with underlying CAO. The resultant delay in diagnosis defers possible relief of disabling symptoms with palliative therapy, including Nd-YAG laser photocoagulation.

Adult↗

Neodymium-yttrium-aluminum-garnet laser in lung cancer.

Neodymium-yttrium-aluminum-garnet laser treatments were performed in 70 patients aged 62 +/- 10 (1 SD) years for incomplete malignancy-induced obstruction of the trachea or main bronchi, or both, associated with uncontrolled cough, dyspnea, atelectasis/pneumonia, and hemoptysis. Forty-three patients had been treated with surgical techniques, chemotherapy, or radiotherapy, or all three, while 27 patients were untreated before laser therapy because of acute respiratory distress. Laser treatment produced palliative improvement in 81% of the treated group (35 of 43), with survival of 4.3 +/- 3.9 months. Unsuccessfully laser-treated patients survived 0.7 +/- 0.4 month (p less than .05). Eighty-five percent of the untreated patients (23 of 27) showed postlaser improvement, with survival of 8.5 +/- 6.9 months. Unsuccessfully laser-treated patients survived 1.4 +/- 0.6 months (p less than .05). Twenty-three of the 27 previously untreated patients underwent radiation therapy after laser treatment. Laser treatments also were administered to 23 patients aged 61 +/- 13 years with complete obstruction of the main bronchi. Of this group, 17 patients had been treated and 6 had not been treated before the laser therapy. Laser treatment was successful in 47% of the treated patients (8 of 17), but there was no difference (p greater than .05) in survival between successfully and unsuccessfully treated patients (3.0 +/- 2.5 vs. 2.9 +/- 4.6 months). Similarly, laser treatment was successful in 50% of the untreated patients (3 of 6), and there was also no difference (p greater than .05) in survival between successfully and unsuccessfully treated patients (3.4 +/- 3.5 vs. 3.5 +/- 2.8 months).(ABSTRACT TRUNCATED AT 250 WORDS)

Airway Obstruction↗

Nd-YAG laser surgery for severe tracheal stenosis physiologically and clinically masked by severe diffuse obstructive pulmonary disease.

Nd-YAG laser surgery was performed on six patients with tracheal stenosis complicating severe diffuse intrathoracic airways obstruction due to emphysema, chronic obstructive bronchitis and/or asthma. Tracheal stenosis was extrathoracic in four patients and both extrathoracic and intrathoracic in two patients. Results suggest that patients with severe chronic obstructive pulmonary disease and asthma have maximal expiratory and inspiratory flow volume patterns that may completely mask extrathoracic and intrathoracic tracheal stenosis. Following relief of tracheal obstruction with laser therapy, substantial improvement can occur both clinically and physiologically, as reflected by symptomatic relief and large increases in Vmax 50I and FVC.

Adult↗

Exercise-induced bronchodilation in asthma.

Of 34 symptomatic adult asthmatic patients (23 men) aged 51 +/- 13 years (mean +/- 1 SD) with moderately severe airways obstruction who underwent maximal exercise testing at room temperature (22 degrees C) and humidity (44 percent RH) using a bicycle ergometer, we identified seven male patients aged 56 +/- 9 years in whom forced expired volume in one second (FEV1) increased greater than or equal to 20 percent over the baseline pre-exercise value (exercise-induced bronchodilation). At maximal exercise, these patients achieved an O2 consumption of 1.4 +/- 0.4 L/min and a minute ventilation of 56 +/- 9 L/min. Baseline FEV1 was 1.3 +/- 0.5 L (SD) (43 +/- 12 percent predicted) and increased to 2.1 +/- 0.5 L at five minutes after exercise and persisted at least 20 minutes. Exercise was repeated in all seven patients on a separate day one to six months later, and results were similar in six. In these seven patients, three minutes of voluntary isocapnic hyperventilation achieving a minute ventilation comparable to that during maximal exercise led to an increase in FEV1 of 20 +/- 18 percent (range 0 to 54 percent). The Vmax50 was 22 +/- 30 percent before, and 10 +/- 21 percent after maximal exercise and 25 +/- 37 percent before, and 11 +/- 22 percent after isocapnic hyperventilation. Pre-treatment with acetylsalicylic acid (mean serum concentration 120 +/- 64 micrograms/ml) in the six patients with reproducible bronchodilation completely blocked exercise bronchodilation in one patient and blunted it in four others. Findings suggest that a subset of adult patients with symptomatic asthma may develop bronchodilation after six to eight minutes of exercise, that exercise-induced bronchodilation may in part be reproduced with isocapnic hyperventilation, and that it may be blocked completely or partially by acetylsalicylic acid, implying mediation by prostaglandins.

Aspirin↗

Lasers in medicine.

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Bronchial Neoplasms↗

Laser in treatment of lung cancer.

We performed treatments with a Nd-YAG laser in 27 patients (19 men) with a mean age (+/- 1 SD) of 63 +/- 15 years for incomplete obstruction of the tracheobronchial tree due to non-oat cell malignant neoplasm associated with cough, dyspnea, hemoptysis, or unresolved atelectasis or pneumonia. Sixteen patients had been previously treated with surgery, chemotherapy, or irradiation. Before surgery,, their mean values were as follows: Karnofsky score, 41 +/- 15 percent; British Medical Research Council dyspnea index, 3.7 +/- 0.6; forced vital capacity (FVC), 64 +/- 23 percent of predicted; and mean forced expiratory volume in one second (FEV1), 52 +/- 19 percent of predicted. Immediate palliative relief was achieved in 23 patients and lasted one-half to six months after a single treatment. After surgery, the mean values were as follows: FVC, 77 +/- 26 percent of predicted; FEV1, 74 +/- 27 percent of predicted; Karnofsky score, 57 +/- 18 percent (p less than 0.05); and dyspnea index, 2.8 +/- 0.7 (p less than 0.05). Complications included one death, and two patients subsequently died of massive pulmonary hemorrhage within seven days of treatment. Rigid bronchoscopy was required in seven patients. We also performed laser treatments in 19 patients (eight men) with a mean age of 64 +/- 10 years who had complete bronchial obstruction due to non-oat cell malignant neoplasm; all but one had received previous non-laser treatment. Before surgery the mean values were as follows: Karnofsky score, 30 +/- 10 percent; dyspnea index, 3.7 +/- 0.5; FVC, 46 +/- 14 percent of predicted; and FEV1, 44 +/- 13 percent of predicted. Immediate relief was achieved in six cases and lasted 0.25 to 1.5 months after a single treatment. After surgery the mean values were as follows: FVC, 59 +/- 8 percent of predicted (p less than 0.05); FEV1, 48 +/- 13 percent of predicted; Karnofsky score, 34 +/- 16 percent; and dyspnea index, 3.4 +/- 0.5. Complications included two deaths, one associated with combustion of the outer sheath of the fiberoptic bronchoscope. Rigid bronchoscopy was required in five patients. Results suggest that laser therapy is most beneficial in patients with partial and not totally occluded airways (X2, p less than 0.05).

Adenocarcinoma↗

Nd-YAG laser in lung cancer.

We administered 45 Nd-YAG laser treatments in 29 patients (18 men) aged 39 to 82 years who had lung malignancy; 26 patients had primary non-oat cell lung cancer and three had metastatic airway malignancy. In all, 25 of the patients had been previously treated with combination(s) of surgical procedure, radiation therapy and chemotherapy. Indications for laser treatment included endobronchial airway obstruction with uncontrolled cough, hemoptysis, dyspnea or unresolved atelectasis-pneumonia. Of 15 patients with partially occluded tracheobronchial airway tumors, immediate palliative relief was achieved in 13 patients and lasted one to six months after a single treatment. In this group there was one postoperative death related to respiratory failure and two patients subsequently died of massive pulmonary hemorrhage. However, of 14 patients with totally obstructed airways, immediate palliative relief was achieved in only five patients and this lasted three weeks to three months after a single treatment. In this group there were two postoperative deaths related to progressive respiratory failure; in one case it was associated with endobronchial combustion of the fiberoptic bronchoscope. All three patients in both groups who died of respiratory failure were in acute respiratory distress and terminally ill before the procedure. These findings suggest that Nd-YAG laser therapy may be most beneficial in patients with partially rather than totally occluded airways due to lung malignancy.

Adenocarcinoma↗

Nd-YAG laser treatment of tracheal stenosis.

We administered Nd-YAG laser treatments in four patients aged 56 to 68 years for severe tracheal stenosis, the tracheal diameters varying between 2.5 and 5 mm. These patients were all dyspneic at rest with talking or dressing and their peak flows ranged from 8% to 36% of predicted. They were not felt to be candidates for surgical excision. Immediate palliative relief was achieved in all patients and lasted two to four months after a single treatment in three patients. One patient died three weeks after laser treatment due to respiratory failure from underlying emphysema. There were no complications of laser therapy. Postlaser therapy the tracheal diameter in each patient was at least 9 mm and peak flow improved to between 25% and 76% of predicted. The results suggest that laser treatment may be beneficial in cases of severe tracheal stenosis.

Aged↗

Partial and complete maximum expiratory flow-volume curves in asthmatic patients with spontaneous bronchospasm.

Bronchodilatation follows a deep inspiration in normal subjects with pharmacologically induced bronchoconstriction. To determine to what extent this occurs in asthmatic patients with spontaneous bronchospasm, we obtained partial (PEFV) and complete (MEFV) maximum expiratory flow volume curves in 20 adults (helium-oxygen responders and nonresponders) and 13 children with asthma. We measured maximum expiratory flow at 25 percent of forced vital capacity from the partial (Vmax - p) and complete (Vmax - c) flow-volume curves and expressed this relationship as the Vmax - p/Vmax - c ratio. Three of the adult subjects and one of the children had a V max-p/V max-c less than 1.0. Following inhalation of nebulized bronchodilators, none of the children or adults had a Vmax - p/Vmax - c ratio less than 1.0. Reasons for Vmax - p to be higher than Vmax - c include bronchoconstriction, decreased lung elastic recoil following a deep inspiration, and time dependence of maximum expiratory flow due to lung inhomogeneity. We conclude that asthmatic patients with spontaneous bronchospasm are only seldom able to obtain bronchodilation following a deep inspiration.

Adolescent↗

Immune complexes, gallium lung scans, and bronchoalveolar lavage in idiopathic interstitial pneumonitis-fibrosis.

We obtained results of lung immune complexes (LIC), circulating immune complexes (CIC), 48-hour gallium lung scans (scans), bronchoalveolar lavage (BAL), and pulmonary function tests in 20 patients with idiopathic interstitial pneumonitis-fibrosis. Sixteen patients had predominantly interstitial (13 cases UIP) and/or intraalveolar (3 cases DIP) cellular disease (group 1). Prior to corticosteroid therapy in group 1, scans were positive in 75 percent, CIC were elevated in 86 percent, LIC were present in 64 percent, and BAL was abnormal in 90 percent. Duration of follow-up after treatment was 3.5 +/- 1.0 year. In group 1 after treatment with corticosteroids in 13 patients and corticosteroids and penicillamine (three patients) and plasmapheresis (one patient), only four patients remain stable or improved. After corticosteroid therapy, elevated CIC returned to normal values despite progressive patient deterioration. In three patients, lung immune complexes were still detected after circulating immune complexes had returned to normal after corticosteroid therapy. In group 2 were four patients with fibrotic disease; scans and CIC were uniformly negative, LIC were weakly present in only one patient, and BAL was abnormal in all. Despite corticosteroid therapy, all have died or deteriorated. These results suggest that positive gallium lung scans, BAL, circulating immune complexes, and to a lesser extent, lung immune complexes are associated with the cellular phase of interstitial pneumonia, but do not reliably identify a corticosteroid-responsive group.

Adult↗