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Study objectives The aims of this study were: to evaluate the performance of a novel arterial biopsy catheter in obtaining pulmonary endovascular samples in hypertensive dogs; to compare the results of pulmonary endoarterial biopsy in hypertensive vs normotensive dogs; and to assess the histologic changes in the hypertensive model. Design and interventions Thirty-four dogs (27 with normal pulmonary arterial pressures and seven with pulmonary hypertension) were catheterized through an external jugular vein to obtain endovascular biopsy samples from distal pulmonary arteries 2 to 3 mm in luminal diameter. To induce pulmonary hypertension, seven dogs were given repeated infusions of 0.6- to 0.9-mm ceramic microspheres into the superior vena cava. Endoarterial samples were obtained at pulmonary systolic arterial pressures ranging from 10 to 110 mm Hg. Measurements and results Sixty-two biopsy catheterization procedures were performed in the 34 dogs. After 12 initial procedures of technique refinement, endoarterial samples were obtained in each of the last 50 procedures (21 in normotensive dogs and 29 in hypertensive dogs). The average number of endovascular biopsy samples retrieved was 7.1 (range, 2 to 12) from a mean of 8.6 (range, 2 to 15) biopsy attempts per catheterization (success rate=83%). The average biopsy piece measured 1.13 mm in length, 0.33 mm in depth, and up to 1.0 mm in width. The biopsy success rates and endoarterial sample sizes were similar in normotensive and hypertensive dogs. Smooth muscle cells and endothelial cells were grown from the biopsy samples. There were no significant procedural complications, except for one self-limited hemorrhage. Histologically, samples obtained from dogs with pulmonary hypertension showed characteristic changes when compared with biopsies from normotensive dogs. Conclusion This new endoarterial biopsy catheter was safe and effective when used to obtain pulmonary endoarterial samples in dogs with normal and experimentally elevated pulmonary arterial pressures. The quality and quantity of the biopsy samples allowed identification of pathologic changes.

Purpose The purpose of this consensus report was to address clinically relevant questions related to the diagnosis and management of acute pulmonary embolism and deep venous thrombosis. Background Physicians are often forced to make decisions about the diagnosis and management of pulmonary thromboembolism even though there are only limited data to guide them. Methods We assessed the relevant literature regarding clinical trials according to levels of evidence. The data on which the opinions of the committee were made were sparse. The consensus opinions, therefore, were often based on experience or intuition, rather than firm data. Results Consensus opinions were given in regard to eight clinically relevant questions. Conclusion We hope that the consensus opinions of this committee will assist others in making clinical decisions while we all await prospective investigations.

The finding of a restrictive pulmonary defect may divert clinicians from considering the diagnosis of chronic thromboembolic pulmonary hypertension because lung volumes are usually normal in this disorder. We have, however, encountered a significant number of these patients with reduced lung volumes. Furthermore, we have observed many patients who have developed parenchymal scars and/or pleural thickening. To determine whether such findings are associated with lung volume restriction, we analyzed patients evaluated at our institution for chronic thromboembolic pulmonary hypertension over a 20-month period in whom thoracic high-resolution CT scans and pulmonary function testing had been performed. Patients with obstructive or restrictive lung disease from another cause were excluded. We compared the presence of lung restriction (total lung capacity below 80% of predicted) with the extent of parenchymal scarring, pleural thickening, and pulmonary artery diameter on CT scans. Of 191 patients evaluated, 51 met criteria for entry. Eleven patients (22%) had lung restriction. Parenchymal scarring was highly associated with lung restriction (p=0.01). Neither pleural thickening (p=0.08) nor pulmonary artery diameter (p=0.80) was associated with lung restriction. Conclusions A significant number of patients with chronic thromboembolic pulmonary hypertension may have restrictive lung defects. The restriction may be due to parenchymal scarring.

Background Inhaled nitric oxide (NO) has been shown to be a selective pulmonary vasodilator in certain patients with primary pulmonary hypertension (PPH). Objectives The purpose of this study was to design and test a system for delivery of NO to awaken, ambulatory patients with PPH and to evaluate this system in the home setting. Methods The ambulatory delivery system consisted of a tank of 80 ppm of NO (balance N 2 ), a modified gas-pulsing device, and nasal cannulas. The pulsing device was set to deliver NO for 0.1 s at the beginning of each inspiration. Results Using this system, eight patients with PPH were studied with pulmonary artery catheters in place. Inhalation of NO led to significant reductions in both mean pulmonary arterial pressure (PAPm) (51±12 to 43±10 mm Hg; p=0.001) and pulmonary vascular resistance (PVR) (790±285 to 620±208 dyne·s·cm −5 ; p=0.01). Three of the eight patients had both greater than 20% and greater than 30% decreases in PAPm and PVR, respectively. No exhaled NO or NO 2 was detectable in any of the eight patients. One patient was discharged home from the hospital on a regimen of inhaled NO. At 9 months, no adverse effects were noted and the system was working well. Conclusions Pulsed delivery of inhaled NO to ambulatory patients with PPH, via nasal prongs, is feasible and, in some patients, leads to significant improvement in pulmonary hypertension. Inhaled 09NO, therefore, may have a role in the long-term treatment of patients with PPH.

Background The decreased morbidity and rapid recovery after thoracoscopic lung biopsy compared with open lung biopsy by thoracotomy is increasingly recognized, as is the ability to obtain satisfactory diagnostic material thoracoscopically. To our knowledge, however, there has been no systematic comparison of specimen quality using different thoracoscopic biopsy techniques. The purpose of this study was to compare histologic features of lung parenchyma obtained by videothoracoscopic forceps and wedge biopsy techniques. Methods Five adult swine were anesthetized, intubated, and ventilated. Sequential left and right videothoracoscopies were performed to obtain biopsy specimens of lung parenchyma using 5-mm endoscopic cupped forceps. Specimens were obtained from fully inflated lung and from partially atelectatic (deflated) lung. Electrosurgery was applied during forceps biopsy for airleak closure. Limited wedge biopsy specimens were obtained using an endoscopic stapler. One hundred thirteen forceps biopsy specimens (55 inflated, 58 deflated) and 24 sections from 8 wedge biopsy specimens were examined. Specimens were assessed for overall histologic quality and ease of microscopic interpretation. Specific histologic features were then evaluated including presence of artifact, congestion and hemorrhage, degree of alveolar inflation, and number of bronchioles and vessels per cross-sectional area. Whole lungs from two animals were examined for extent and depth of lung injury at the areas of biopsy. Results No major differences in overall microscopic specimen quality were detected among the different techniques nor were significant differences noted between lung inflated and lung deflated forceps biopsy technique. Wedge sections contained more vessels per unit area (p Conclusions Multiple 5-mm forceps biopsy specimens were of comparable quality to single wedge biopsy specimens obtained by endoscopic stapling. Although greater numbers of vessels were present in endoscopic stapled wedge biopsy specimens, multiple forceps biopsy specimens in fact, contain amply sufficient vessels for histologic analysis.

Nitric oxide (NO) is a potent dilator of vascular smooth muscle that likely represents an important endothelium-dependent relaxing factor. Recent interest has focused on inhaled NO as a pulmonary vasodilator. The purpose of this study was to design a reliable NO delivery system with on-line monitoring of NO and nitrogen dioxide (NO 2 ) concentrations, and to test the effects of inhaled NO in a dog model of acute hypoxic pulmonary vasoconstriction (HPV). Six canines were studied. Marked HPV was induced using a hypoxic gas mixture. Using a standard blender, NO was delivered through a volume-cycled ventilator. We were able to rapidly adjust the delivered NO concentration using this system. An on-line chemoluminescence analyzer was used to continuously measure NO and NO 2 concentrations. Inhaled NO at 40 and 80 ppm for 30 min rapidly reversed HPV in all animals (PVR 502±154 dynes·s·cm −5 with hypoxia, 244 ±52 with 40 ppm NO, 227±47 with 80 ppm NO). No significant NO 2 or methemoglobin production was noted during the study. We conclude that inhaled NO can be easily delivered through a ventilator and the dose rapidly adjusted, NO and NO 2 concentrations can be monitored continuously on-line, inhaled NO rapidly reverses HPV in dogs, and with short-term NO inhalation, there is no significant NO 2 or methemoglobin formation. Inhaled NO may, therefore, have a future clinical role as a new agent in the diagnosis and treatment of other forms of pulmonary hypertension.

A reduced diffusing capacity for carbon monoxide (DCO) is common among patients with chronic thromboembolic pulmonary hypertension (CTEPH) and often persists for more than a year following successful pulmonary thromboendarterectomy (PTE). To determine the relative contribution the pulmonary membrane diffusing capacity (DM) and pulmonary capillary blood volume (VC) make to the reduction in DCO, we measured both in 29 patients with CTEPH before and approximately 3 weeks after PTE. Mean preoperative DM was reduced in patients with CTEPH (28 mL min-1 mm Hg-1 vs 43 mL min-1 mm Hg-1 in control subjects; p0.001) and dropped significantly following PTE (21 mL min-1 mm Hg-1; p0.001). Mean preoperative VC was mildly reduced in the CTEPH group compared with healthy control subjects (57 vs 67 mL; p = 0.044) and did not rise following PTE (57 mL pre-PTE vs 54 mL post-PTE; p0.05) despite substantial reduction in mean pulmonary artery pressure and increase in cardiac output after surgery. We conclude that the low DCO observed in patients with CTEPH before and after PTE is principally caused by a reduced DM and to a lesser extent by a low VC. The mechanisms responsible remain speculative but may reflect pathophysiologic changes in the pulmonary microcirculation caused by chronic pulmonary hypertension that did not improve in the postoperative period studied.

A case of digital clubbing in a patient with pulmonary artery sarcoma and severe pulmonary hypertension is presented. The differential diagnosis of clubbing and clinical features of pulmonary artery sarcoma are reviewed with emphasis on the possible association of clubbing with pulmonary artery sarcoma.

The status of small pulmonary arteries may influence diagnosis, surgical selection and postoperative outcome of patients with chronic major vessel thromboembolic pulmonary hypertension (CTEPH). Therefore, in patients with the established diagnosis of CTEPH, lung tissue was obtained by biopsy (15 patients) or at autopsy (16 patients) to assess the histopathologic composition of small pulmonary arteries. Pathologic examination disclosed the full range of pulmonary hypertensive lesions in the small arteries, including plexogenic lesions. The type and extent of hypertensive lesions did not relate to preoperative hemodynamic values, to patient age, or to symptom duration. The findings indicate that primary pulmonary hypertension cannot be differentiated from potentially correctable CTEPH on the basis of histopathologic findings in small pulmonary arteries. Furthermore, none of the histologic findings preclude a positive hemodynamic and clinical result from pulmonary thromboendarterectomy. However, development of these hypertensive changes may explain the deterioration which these patients experience preoperatively over time.

While bronchoalveolar lavage has been shown to be more sensitive than brush biopsy (BB) for the diagnosis of Pneumocystis carinii pneumonia in AIDS patients, some have reported that BB occasionally is positive in spite of a negative BAL. Many bronchoscopists, therefore, continue to perform routine BB when doing bronchoscopy on AIDS patients. We performed a retrospective study of all fiberoptic bronchoscopies done on human immunodeficiency virus-infected patients over a one-year period at our institution to determine if the use of BB added to the diagnostic yield of bronchoscopy over that of BAL alone. Of 84 bronchoscopies in which BB was performed in addition to BAL, BB yielded no diagnoses that were not obtained by BAL. Brush biopsy added approximately $400 to the cost of bronchoscopy. We conclude that BB should not be routinely done when performing bronchoscopy on HIV-infected patients.

After pulmonary thromboendarterectomy, performed for relief of chronic thromboembolic pulmonary hypertension, perfusion lung scans have frequently disclosed new perfusion defects in segments served by undissected pulmonary arteries. Our hypotheses were that these new postoperative defects occurred with great frequency and did not represent postoperative vessel occlusion. We retrospectively reviewed the preoperative and postoperative perfusion scans of 33 consecutive patients undergoing pulmonary thromboendarterectomy. New postoperative perfusion defects were noted in 23 of 33 patients. The incidence of new defects was increased tenfold in segments that had (1) normal preoperative angiographic findings, (2) normal preoperative radionuclide perfusion, and (3) not been entered at the time of surgery. Postoperative angiograms, available in 15 of 33 patients, documented the nonembolic, nonocclusive nature of the new perfusion scan defects. The most plausible alternate explanation for this previously undescribed finding is a redistribution of pulmonary arterial resistance induced by the thromboendarterectomy, namely, a pulmonary vascular "steal."

Thromboendarterectomy is the treatment of choice for chronic large vessel thromboembolic pulmonary hypertension. To identify the mechanisms responsible for the improvement in gas exchange following thromboendarterectomy, we studied nine patients with chronic thromboembolic pulmonary hypertension before and eight to 18 months after surgery using the multiple inert gas elimination technique. Preoperatively, all subjects had pulmonary hypertension and were hypoxemic or had an elevated P(A-a)O 2 . The V · A / Q · distribution was widened with an elevated V D /V T and a low cardiac index. After thromboendarterectomy, significant improvement had occurred. The V · A / Q · distribution had narrowed to near normal, and the cardiac index increased. It was concluded that thromboendarterectomy improved gas exchange both by improving V · A / Q · relationships and by increasing cardiac output.

There is widespread acceptance of the thesis that in a patient with suspected embolism, a normal perfusion lung scan excludes the diagnosis of acute pulmonary embolism. However, limited published data exist which validate this thesis. We have explored this question by longitudinal follow-up of 68 patients who were referred for lung scanning to rule out embolism and proved to have normal perfusion lung scans. Risk factors for venous thromboembolism among these patients were similar to those reported in prior series of patients with pulmonary embolism. Our data support the widely-held views that: 1) a normal perfusion lung scan excludes the diagnosis of clinically significant pulmonary emboli; 2) the diagnostic work-up for suspected pulmonary embolism need not extend beyond a normal perfusion scan; 3) anticoagulant therapy can be discontinued after a normal perfusion scan, except in the presence of documented venous thrombosis; and 4) a normal lung scan has the same value in ruling out embolism in man as does a normal pulmonary angiogram.

Lavage limited to an isolated lobe was performed on multiple occasions using a cuffed fiberoptic bronchoscope in a patient with alveolar proteinosis. Sequential ventilation-perfusion scintiphotoscans were used to preselect and follow the functional behavior of the lavaged lobe. Lavage led to functional improvement. The technique of fiberoptic bronchoscopic lobar lavage is simple and may find application in patients in whom lavage of an entire lung may be hazardous.

Major vessel chronic thromboembolic pulmonary hypertension is potentially remediable by thromboendarterectomy. The diagnosis often has been delayed because a lung perfusion scan demonstrated modest defects thought to be incompatible with severe vascular obstruction. To define the relationships between perfusion scan abnormalities, angiographic findings, and hemodynamic data, we analyzed 25 consecutive patients with chronic major vessel thromboembolic pulmonary hypertension who subsequently underwent thromboendarterectomy. We found that the perfusion lung scan consistently caused us to underestimate the severity of pulmonary arterial obstruction as defined by pulmonary angiography. Furthermore, there was no significant correlation between the severity of hemodynamic compromise and the extent of obstruction defined by perfusion scan or angiogram. These findings suggest that, when pulmonary hypertension is known or suspected, the diagnosis of correctable, chronic major vessel obstruction should be pursued by angiography and hemodynamic assessment even though the perfusion scan may demonstrate only two segmental defects.

To evaluate the utility of transthoracic needle aspiration biopsy (TTNAB) following negative fiberoptic bronchoscopy (FOB) in a patient with a solitary pulmonary nodule (SPN), we reviewed the records from 262 patients who had undergone TTNAB over an eight-year period. Fifty-eight patients had a SPN and met the criteria for inclusion in this series. Twenty-five of these (43 percent) were diagnosed by TTNAB; 24 had malignant lesions; one had M tuberculosis. Of the remaining 33 patients, 18 went on to definitive diagnostic procedures (surgery, repeat FOB or TTNAB). Nine of these patients had a malignancy. Fifteen patients were followed long-term; one was diagnosed with carcinoma two years after the initial work-up. Carcinoma was not found in any patient under 40 years of age. A benign lesion was diagnosed by TTNAB in only two patients. We conclude that TTNAB is a valuable procedure in the evaluation of patients with a SPN and negative FOB. While a negative FOB and TTNAB do not assure that the lesion is benign, a complex of variables influences the decision regarding thoracotomy vs careful follow-up.

Patients with fibrosing mediastinitis causing obstruction of pulmonary veins and arteries may present with many of the historic, physical, and laboratory findings of patients with pulmonary hypertension due to chronic thrombotic obstruction of major pulmonary arteries. Because the latter is subject to surgical correction, and the former is not, it is important to differentiate between the two and to be aware of the similarities in presentation. Three patients with pulmonary hypertension due to compression of pulmonary veins and the right pulmonary artery by fibrosing medias tinitis are presented who illustrate these points. A review of the literature documents other instances in which vascular involvement due to fibrosing mediastinitis has mimicked other types of pulmonary hypertension.

Fourteen patients with adult respiratory distress syndrome were admitted to the medical intensive care unit and received bedside heart catheterization with the use of a balloon-tipped, flow directed catheter. Four of the 14 (29 percent) were found to have left ventricular failure (LVF), defined as a pulmonary artery wedge pressure greater than 12 mm Hg. Analysis of the standard clinical and laboratory data demonstrated no criteria which could differentiate those patients with LVF from those without. Three of the four patients indentified as having LVF responded to therapy directed toward LVF with substantial clinical improvement.

Tracheal injury continues to be a major complication of the use of cuffed endotracheal/tracheostomy tubes. To assess the determinants of such injury, 22 dogs were studied. It was found that the degree of tracheal injury induced by high compliance-low pressure tracheal cuffs was substantially less than that provoked by low compliance-high pressure cuffs. Marked compromise of tracheal arterial circulation by the high pressure cuffs was demonstrated by vascular injection studies. Tantalum tracheography was useful in assessing the presence of cuff-induced mucosal injury and in delineating tracheal distortion induced by the cuffs. Comparing the cuff compliance (pressure-volume) curve obtained outside the trachea with that obtained inside the trachea can provide a reasonable guide to cuff suitability in terms of the pressure it will apply to the trachea waff. Intercurrent hypotension or the use of positive-pressure ventilation had no discernible influence on extent of tracheal injury. It is cmicluded that high compliance-low pressure cuffs should be used exclusively in clinical practice.

Eighteen COPD patients enrolled in a comprehensive, multidisciplinary pulmonary rehabilitation program were randomly assigned to perform either: 1) walking, or 2) ventilatory muscle exercise training (VMT) using a prototype, portable device for isocapnic hyperventilation training. Both groups performed exercise training at home. Twelve patients completed the study and follow-up evaluation (five VMT, seven walkers). Pulmonary function did not change in either group. For the VMT patients, there were modest increases in ventilatory muscle endurance and exercise performance. V ˙ o 2 max and V ˙ Emax increased significantly. For the walkers, only walking endurance time increased significantly. These results indicate that isocapnic hyperventilation exercise training can be performed successfully by COPD patients in an unsupervised home setting and can lead to improvement in both ventilatory muscle endurance and exercise performance. Walking exercise training did not improve ventilatory muscle endurance.

A retrospective review of 15 patients with angiographically- or biopsy-documented primary pulmonary hypertension was performed to assess the value of pulmonary perfusion scanning in noninvasively differentiating these patients from those with potentially operable, chronic (large-vessel) thromboembolic pulmonary hypertension. None of the 15 patients with primary pulmonary hypertension demonstrated a segmental or larger perfusion defect whereas such defects have been uniformly present in previous reports of patients with large-vessel thromboembolic pulmonary hypertension. While perfusion scans in primary pulmonary hypertension may show certain abnormalities, the presence of segmental or larger perfusion defects should suggest the diagnosis of potentially correctable, large-vessel thromboembolic pulmonary hypertension rather than small-vessel, obliterative (primary, idiopathic) pulmonary hypertension.

The regional distribution of pulmonary ventilation is nonuniform in health and disease. Single and multiple breath techniques have been developed to assess this nonuniformity. Limitations of these expired gas techniques include: identification of only several of the component washout exponentials and preferential representation in this single curve of the better ventilated spaces. In ten normal persons and eight patients we assessed the washout of ventilation by three simultaneous techniques and obtained three clearance curves: nitrogen washout with 100 percent O2; washout of 133Xe at the mouth with 100 percent O2; clearance of 133Xe from the patients' lung fields. A scintillation camera/computer system was utilized to provide clearance curves for 133Xe from selected zones of interest varying from both lungs to sublobar regions. In normal persons all three curves were superimposable. In patients with diffuse lung disease the expired curve for N2 and 133Xe at the mouth were abnormal but superimposable, while the xenon clearance over the lung fields revealed slower and more abnormal clearances. These latter curves provided an appreciation of the presence, localization, and extent of both slow and fast spaces.

A 69-year-old man, in whom extensive embolic obstruction of the pulmonary arteries had likely been present for ten years, and who exhibited marked pulmonary hypertension and compromise of right ventricular function, was submitted to thromboendarterectomy. The course after surgery included extensive hemorrhagic infiltration of the reperfused lung zones (predicted before operation), which required special management. Four months after surgery, reduction in pulmonary vascular resistance of almost 50 percent was demonstrated. The patient is improved and maintains normal activity more than two years after surgery. The patient demonstrates that, despite several negative features before operation, successful thromboendarterectomy is possible, if recent technical and conceptual advances are applied in a coordinated manner during all phases of management.

Twenty patients undergoing fiberoptic bronchoscopy (FOB) (bronchofiberscopy) were studied with serial arterial blood gas analyses. Ten patients were managed using a 40 percent Venturi mask with a 2-cm opening cut out for the FOB; there were ten other patients, with this opening modified by a thin rubber diaphragm with a slit for insertion of the FOB. Both masks decreased the extent of hypoxemia after bronchoscopy, but the mask with the diaphragm provided significantly higher PaO2 values. A significantly higher mean FIO2 was found at the carina in the group using the diaphragm-modified mask. This study suggests that declines in PaO2 after bronchoscopy can be avoided in most patients undergoing diagnostic FOB by using a diaphragm-modified 40 percent Venturi mask during and after the procedure. However, patients with a PaO2 below 60 mm Hg before bronchoscopy may require other measure to avoid potentially hazardous degrees of hypoxemia after bronchoscopy.

Alpha -1-antitrypsin is the main protease inhibitor in human serum. Certain variants or phenotypes of this protein are associated with diseases of the liver and lung. The availability of purified alpha-1-antitrypsin of various phenotypes would be useful in studies exploring these associations. A two-step purification procedure is presented which involves affinity chromatography on isolubilized conconavalin A followed by preparative starch gel electrophoresis. This simple and rapid method has provided both MM and ZZ alpha-1-antitrypsin in highly pure and active form.

Pulmonary perfusion ( Q ˙ ) and ventilation ( V ˙ ) scintiphotography was performed in 16 patients undergoing diagnostic fiberoptic bronchoscopic examinations. Regional V ˙ / Q ˙ did not change in the majority of the patients who developed hypoxemia after bronchoscopic studies. An improvement in V ˙ / Q ˙ was detectable in the patients with a rise in arterial oxygen pressure (PaO 2 ) after bronchoscopic examination, and this rise was associated in most with the removal of mucous plugs or extensive secretions. The data indicate that the behavior of PaO 2 after bronchoscopic study is dependent upon both the extent of lavage and the yield of the procedure in terms of secretions and plugs. The results also indicate that the removal of secretions or plugs can be associated with rapid return of regional V ˙ and Q ˙ .

A survey of 109 pulmonary physicians representing both private practice and academic medicine was conducted to learn their practice of management and treatment of interstitial lung disease. Of the 109, 25 (23 percent) responded. Twenty-two of 23 routinely obtain tissue diagnosis. The routine method was transbronchial biopsy by 15 physicians vs open lung biopsy by seven. Few (n = 5) use BAL cell analysis. The majority of clinicians used two to four criteria to initiate therapy. Physiology laboratory data were the predominant criteria used by the majority of physicians and also were most commonly used to monitor a patients course over time. Prednisone was the drug of choice for therapy. Immunosuppressive therapy was not used until failure of steroid therapy was observed. There was little consistency in the diagnostic procedures applied, criteria for the decision to treat, the drugs used to treat, or methods for monitoring.

In patients with chronic obstructive pulmonary disease (COPD), the clinical differentiation between dyspnea due to left ventricular dysfunction and that due to pulmonary events is difficult. Invasive techniques have been the only reliable diagnostic approach. To assess the potential value of noninvasive techniques in this context, 27 patients with COPD and with clinically suspected left ventricular dysfunction were studied by echocardiography, radionuclide angiography, and right cardiac catheterization. In 20 (74 percent), adequate echocardiograms were obtained. Of these 20 patients, 17 had normal pulmonary arterial wedge pressures at rest and during submaximal handgrip exercise. Sixteen of these 17 had normal left ventricular performance by all three echocardiographic criteria used; in one patient, two criteria were not interpretable, but the third was normal. Results of radionuclide studies were normal in 15 patients, borderline in one, and not measurable in one. Of the three patients with abnormal wedge pressures, at least one echocardiographic criterion was abnormal in all. Radionuclide data were abnormal in two and not measurable in one. We conclude that left ventricular dysfunction is infrequently present in patients with COPD in whom such dysfunction is clinically suspected, that the two noninvasive techniques described here can be applied successfully to a high percentage of patients with COPD, and that the agreement among echocardiographic, radionuclide, and wedge pressure data is excellent.

The therapeutic application of endobronchial lavage has been inhibited by concern regarding alterations in the exchange of gases, particularly hypoxemia, and by the technical complexity of the procedure. Using a cuffed fiberoptic bronchoscope with which lavage could be restricted to one lobe, we studied the sequence of alterations in the exchange of gases after lavage and the attendant disturbances in ventilation and perfusion in ten mongrel dogs following lobar lavage with 1,850 ml of physiologic saline solution. Sequential scintiphotographs of ventilation and perfusion and sequential measurements of arterial blood gas levels were obtained. Linkage of the computer to the scintillation camera allowed quantification of data on ventilation and perfusion from the lobar area of interest. Lavage induced a reduction in regional ventilation and perfusion in all dogs. The decline in ventilation preceded that in perfusion, and the computed ratio of ventilation over perfusion reached its lowest point during the first 30 minutes after lavage. The arterial oxygen pressure (PaO2) declined in all dogs from a mean baseline value of 87 mm Hg to a mean value of 76 mm Hg at 30 minutes after lavage and gradually returned to a mean of 85 mm Hg by six hours after lavage. The lowest values for PaO2 occurred after balloon occlusion prior to lavage. Calculations of shunt showed a minimal increment in the intrapulmonary shunt (QS/QT). In the normal dog, lohar lavage induces mild hypoxemia due to an imbalance of ventilation and perfusion that resolves within six hours.

A flexible, fiberoptic device, fitted with an inflatable distal balloon, has been used to directly visualize the great veins, right cardiac chambers, pulmonary arteries, and experimental emboli in vivo in the dog. Insertion and manipulation of the device have been well-tolerated. The angioscope has significant potential for investigative and clinical application.

The function of the accessory respiratory muscles (ARM) of the neck were studied in a quadriplegic patient suffering from a C 2-3 lesion of the cervical spinal cord. Subtotal expiratory paralysis resulted in an essentially complete loss of expiratory reserve volume such that residual volume and functional residual capacity were equal (RV = FRC). Tidal volume and vital capacity were severely reduced. Being extrinsic to the chest, the ARM of the neck functioned independently of changes in thoracic gas volume; however, their performance appeared posturedependent, and was less efficient in the sitting position. Despite the fact that the ARM preferentially expanded the upper part of the ribcage, significant V/Q mismatch did not seem to occur. Voluntary use of glossopharyngeal breathing (GPB) greatly enhanced the patient's ventilatory capability. Flow volume data during GPB documented the efficiency of the glossopharyngeal muscles, which function as a positive pressure pump to force air into the lungs.

A case is presented which demonstrates the value of bronchial arteriographic studies in localizing and treating hemoptysis. The patient was bleeding from an old posttuberculous bulla and for several reasons was not a candidate for surgery. Bronchial arteriographic studies demonstrated both hypervascularity in the region of the cavity and also a mycotic aneurysm of a bronchial artery. After therapeutic embolization with gelatin (Gelfoam), the hypervascularity and aneurysm were no longer opacified. Active bleeding abruptly ceased and, except for a single mild recurrence, has not recurred during the three months since therapeutic embolization. The major theoretic risk of bronchial arteriographic study and therapeutic embolization is spinal injury. It is believed that permanent injury can almost always be avoided, providing proper technique is used.

Metastatic disease from colorectal carcinoma to the tracheobronchial tree has previously been reported in only 15 cases. Various modalities of treatment have been attempted but have met with limited success. We describe an additional nine cases, as documented by fiberoptic bronchoscopy, treated by Nd-Yag laser therapy debulking. Improvement in bronchial patency was evidenced visually in each case, and relief of symptoms occurred in eight cases. Survival periods of up to 21 months occurred. This type of metastatic disease may be more common than previously reported and combination therapy to include Nd-Yag laser debulking offers a safe and effective alternative in the palliative management of pulmonary symptoms and increased survival in select patients.

Acquired bronchial stenosis has been associated with sleeve resection, tuberculosis, sarcoidosis, and prolonged intubation. Various modalities of therapy for the relief of such stenoses include surgery, cryotherapy, and laser photoresection. Several recent reports have described the use of angioplasty balloon catheters for dilatation of stenotic areas. In two patients with endobronchial stenosis, we found that balloon dilatation, using either angioplasty or valvuloplasty catheters, in combination with laser photoresection can be safely and effectively performed with alleviation of pulmonary symptoms.

The prostaglandins are a group of pharmacologically potent lipid compounds whose role in pulmonary pathophysiology remains to be defined. There is not question that these compounds can induce constriction (PGF) or relaxation (PGE) of the smooth muscle in bronchi and pulmonary vessels. There is no question that the lungs are a major site of both the synthesis and degradation. These facts make speculation about the role of the prostaglandins in pulmonary disorders a tempting exercise. However, the current paucity of clinical data prevents any valid assessment of such speculation at this time and emphasizes the need for continued investigation of the role of prostaglandins in patients with lung disease.

Obstruction of the pulmonary artery can be due to a variety of conditions, including chronic thromboembolic disease, neoplasia, and fibrosing mediastinitis. Differentiation can be difficult. We report a case of malignant fibrous histiocytoma causing intravascular obstruction and include a review of the literature.

Among 28 patients with chronic obstructive pulmonary disease (COPD) with increasing dyspnea, the resting mean pulmonary arterial wedge pressure was elevated (greater than 12mm Hg) in 4 and became abnormal with exercise in 3 other subjects. Stroke volume index was reduced (less than 36 ml/beat/M2) in 16 of 26 patients (62 percent). The resting pre-ejection period index was prolonged (greater than 144 msec) in 17 patients (65 percent), while the left ventricular (LV) ejection time index was reduced (less than 408 msec) in 23 patients (88 percent). The ratio of the pre-ejection period to the LV ejection time was within the normal range (0.309 to 0.381) in only 3 of 26 patients (12 percent). Echocardiographic measurements of LV function were normal in nine patients, seven of whom had one or more abnormal values for systolic time intervals (STIs). These data suggest that reduced LV filing results in abnormal values for STIs in patients with COPD, and therefore that in such patients STIs are not accurate indices of LV function.

In the first 100 patients operated on for C T-E PH, three were referred with the diagnosis of UPAA having been made elsewhere. We found that many features of these two conditions are so similar that differential diagnosis is very difficult. Shared features may include findings on chest x-ray film, pulmonary angiography, CT scan and MRI studies. Since the two conditions vary substantially with respect to the methods of potential surgical correction, recognition of this possible differential diagnostic dilemma is important.