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Nutritional status and lung function in patients with emphysema and chronic bronchitis.

This study compared the nutritional status of patients with emphysema and chronic bronchitis and examined the relationship between lung dysfunction and nutritional depletion in patients with emphysema. There was no evidence of nutritional depletion in patients with chronic bronchitis (n = 4). In contrast, patients with emphysema (n = 14) were somatically depleted. They exhibited lower values for percent ideal body weight (%IBW), arm muscle circumference (AMC), and triceps skin fold thickness (TSF) (p less than 0.05) than did patients with chronic bronchitis. The creatinine height index (CHI) was also lower in this group, but the difference was not significant (p = 0.08). In patients with emphysema, there was a good correlation between the degree of airflow obstruction and of somatic depletion (FEV1 vs %IBW, r = 0.699, p less than 0.001). The single-breath diffusing capacity (DCO) also correlated well with %IBW (r = 0.6052, p less than 0.019). These results confirm that patients with emphysema are frequently nutritionally depleted and suggest that nutritional depletion contributes to lung dysfunction in emphysema.

Aged↗

Distinguishing among asthma, chronic bronchitis, and emphysema.

The history holds the central role in distinguishing among asthma, chronic bronchitis, and emphysema. A personal or family history of atopy, a history of seasonal worsening of disease in response to a known environmental agent, perhaps seasonal, and marked variability in the severity of airflow obstruction, often with dramatic responsiveness to bronchodilator drugs, strongly support the diagnosis of asthma. Exacerbation of wheezing by exposure to cold air or following the ingestion of a drug, and asthma variants, such as nocturnal cough responsive to bronchodilator agents or exercise-induced asthma, all support the diagnosis of asthma. Peripheral blood eosinophilia or sputum eosinophilia support the diagnosis of asthma providing other known causes of eosinophilia can be excluded. Positive skin tests are helpful in establishing the atopic state and indicating its possible etiology. An elevated serum IgE level supports the diagnosis of asthma; a normal one does not exclude it. Cigarette smoking is a common background factor in both chronic bronchitis and emphysema, and both diseases are infrequently observed in the absence of this history. Long-standing mucous hypersecretion preceding airflow obstruction suggests the presence of chronic bronchitis. Progressive dyspnea on effort as the predominant symptom suggests the possibility of emphysema. Reversibility of airflow obstruction suggesting the presence of asthma can be obtained either from physical examination or serial pulmonary function studies. Apart from this, neither of these techniques is very useful in differential diagnosis. Evidence of emphysema in the chest roentgenogram and a low value of the Dco/VA are sensitive tests for the presence of emphysema but are not highly specific. The main value of making the differentiation among these three conditions now lies in establishing a prognosis and guiding the use of corticosteroid therapy. As new information accumulates on the pathogenesis, prevention, and treatment of asthma, chronic bronchitis, and emphysema, precise diagnosis is likely to acquire increased significance.

Adult↗

Comparison of dynamic lung function indices during forced and quiet breathing in upper airway obstruction, asthma, and emphysema.

We compared the dynamic lung function indices in patients with asthma (n = 27), emphysema (n = 20), and UAO (n = 18), with the purpose being to examine whether different patterns of abnormalities could be found and which tests were most discriminative among the three groups. Forced expiratory indices were measured (FEV1; PEF; MEF50%), as well as indices obtained during quiet breathing (Raw; Gaw; Gaw/VL). The three groups were comparable as far as PEF was concerned (about 60 +/- 20 percent of predicted, yet the group with UAO showed significantly larger FEV1 (84 percent of predicted vs 55 percent and 57 percent of predicted in asthma and emphysema respectively), and larger MEF50% (71 percent of predicted vs 25 percent and 23 percent of predicted in the other groups), and the group with asthma had the largest Raw (0.37 +/- 0.18 kPa.s.L-1 vs 0.24 +/- 0.13 in UAO and 0.22 +/- 0.10 in emphysema). From these functional tests, several ratios were derived which were discriminative among the three groups. Upper airway obstruction could be recognized by a significantly lower PEF/MEF50% ratio and higher FEV1/PEF ratio than in the other conditions. Furthermore, a distinction between asthma and emphysema could be made by comparing airway patency during forced and quiet breathing, ie, the MEF50%/Gaw ratio. This ratio was, in fact, significantly different for all three groups, having the lowest value in emphysema (0.19 +/- 0.08 kPa vs 0.44 +/- 0.23 kPa and 0.63 +/- 0.34 kPa in asthma and UAO, respectively). Within the group with UAO, those with variable intrathoracic obstruction showed the least difference from asthma and emphysema for the measured indices.

Adult↗

The usefulness of 99mTc-Technegas scintigraphy for diagnosing pulmonary impairment caused by pulmonary emphysema.

X-ray computed tomography (CT) has been used for diagnosis of pulmonary emphysema because it can reveal the morphology of low attenuation areas. Recently, 99mTc-Technegas imaging, one of several types of scintigraphic techniques, has been used for ventilation scintigraphy. Technegas scintigraphy was performed on 15 patients with pulmonary emphysema, and we compared the extent and degree of abnormal findings on Technegas scintigraphy with the extent of low attenuation areas shown by CT. We classified the findings of Technegas imaging into three grades, from mild to severe, according to the extent of peripheral irregularity and central hot spot formation. We also classified the findings of CT as centrilobular emphysema into three grades from mild to severe according to the extent of low attention areas in the peripheral lung fields. In 5 cases, CT and Technegas assessment resulted in equivalent diagnoses. In eight cases, Technegas images showed more detailed findings than CT images. In the two remaining cases, which were diagnosed as panlobular emphysema on CT, Technegas images showed the severe stage. Technegas scintigraphy was useful for diagnostic assessment of pulmonary emphysema, especially for panlobular emphysema, which is difficult to distinguish from the normal lung condition by CT assessment.

Adult↗

Idiopathic giant bullous emphysema (vanishing lung syndrome): imaging findings in nine patients.

OBJECTIVE: We reviewed the imaging findings in nine patients with idiopathic giant bullous emphysema. This progressive condition is characterized by large bullae, usually seen in association with several forms of emphysema, and usually occurs in young men, most of whom are smokers. MATERIALS AND METHODS: Nine patients with chest radiographic evidence of a bulla or bullae occupying at least one third of a hemithorax, who had also been examined with high-resolution CT, were included in this retrospective study. We examined the size, distribution, and locations of bullae. On high-resolution CT scans, bullae were categorized as predominantly subpleural or intraparenchymal. RESULTS: In eight of the nine cases, the chest radiographs showed variable asymmetry in the distribution of bullae. Bullous disease involved predominantly the upper lobes. High-resolution CT showed bullae from 1 to 20 cm in diameter, but most were 2-8 cm in diameter. Paraseptal emphysema and subpleural bullae were the predominant findings in all nine patients. Seven patients had separate centrilobular emphysema of various degrees and intraparenchymal bullae. None of the intraparenchymal bullae were larger than 2-3 cm. Additionally, two non-small-cell lung cancers were seen in our series. CONCLUSION: The dominant and consistent feature seen on high-resolution CT scans in both smokers and nonsmokers is extensive paraseptal emphysema merging into giant bullae. Associated centrilobular emphysema, seen in cigarette smokers, is the important variable finding for determining the extent of underlying parenchymal disease, which may help in the preoperative assessment of giant bullous lung disease.

Adult↗

Quantitative analysis of pulmonary emphysema: three-dimensional fractal analysis of single-photon emission computed tomography images obtained with a carbon particle radioaerosol.

OBJECTIVE: The purpose of this study was to quantify the heterogeneous distribution of a carbon particle radioaerosol in the lungs of patients with pulmonary emphysema using single-photon emission computed tomography (SPECT) and fractal analysis. SUBJECTS AND METHODS: Ventilation SPECT was performed on 19 patients with pulmonary emphysema, seven patients with suspected pulmonary emphysema, and 14 healthy volunteers. We delineated the lungs using five cutoff levels (15%, 20%, 25%, 30%, and 35% of the maximal pixel radioactivity) and measured the total number of pixels in the areas surrounded by the contours obtained with each cutoff level. We calculated fractal dimensions from the relationship between the total number of pixels and cutoff levels transformed into logarithms. RESULTS: The fractal dimensions increased with the severity of pulmonary emphysema. The fractal dimensions for patients with pulmonary emphysema, patients with suspected pulmonary emphysema, and healthy volunteers were 2.03+/-0.61 (mean +/- SD), 0.77+/-0.09, and 0.59+/-0.06, respectively. A significant difference (p < .0005) in the fractal dimension was found when any of these three groups was compared with any other group of subjects. CONCLUSION: Three-dimensional quantitative evaluation of the emphysematous lung was possible using SPECT and fractal analysis. Our results suggest that fractal analysis can quantify the heterogeneity of the distribution of a carbon particle radioaerosol in the lung. Fractal analysis appears to be applicable for routine clinical use because it is simple and the fractal dimensions can be obtained easily without using special software.

Aged↗

[A comparative study of computed tomographic techniques for the detection of emphysema in middle-aged and older patient populations].

Helical-scan computed tomography (CT) is now widely utilized as a mass screening procedure for lung cancer. By adding 3 slices of high-resolution CT (HRCT) to the standard screening procedure, we were able to compare the efficacy of helical-scan CT and HRCT in detecting pulmonary emphysema. Additionally, the prevalence of emphysema detected by HRCT was examined as a function of patient age and smoking history. The subjects (106 men and 28 women) were all community-based middle-aged and older volunteers who participated in a mass lung cancer screening program. Based on visual assessments of the CT films, emphysema was detected in 29 subjects (22%) by HRCT, but in only 4 (3%) by helical-scan CT. Although the prevalence of emphysema was higher among subjects with a higher smoking index, no correlations with age were observed. We concluded that the efficacy of helical scan CT in detecting pulmonary emphysema can be significantly improved with the inclusion of 3 slices of HRCT, and confirmed that cigarette smoking is linked to the development of pulmonary emphysema.

Aged↗

[The clinical study of pulmonary emphysema with pulmonary fibrosis].

OBJECTIVE: Emphysema and interstitial pulmonary fibrosis are two different diseases in clinical manifestation and pathology, but it was noticed that there were cases diagnosed as pulmonary emphysema and pulmonary fibrosis. It is necessary to study the relationship between the clinical aspects of these cases. METHODS: 11 patients with emphysema and pulmonary fibrosis were found in the past five years. Clinical symptoms, radiographic features, arterial blood-gas, lung function testing and computed tomography of the chest were analyzed. RESULTS: These patients had a long history of cigarette-smoking. Their clinical features are those of both emphysema and pulmonary fibrosis. CONCLUSIONS: Although emphysema and interstitial pulmonary fibrosis are two different diseases, they could coexist in some patients. Their clinical features do not like either of the two diseases. HRCT is an important method for discovering the coexistance of pulmonary emphysema and interstitial fibrosis.

Diagnosis, Differential↗

Thigh emphysema and hip pain secondary to gastrointestinal perforation.

A patient presenting with thigh emphysema and hip pain may suggest intra-abdominal pathology. Three new and 19 previously reported cases of thigh emphysema secondary to bowel disease are reviewed. The thigh and hip manifestations can obscure the primary intra-abdominal process either due to the obvious emphysema or to the obtunded abdominal signs secondary to associated neuropathy. Only one of 22 patients with thigh emphysema secondary to bowel perforation had gas gangrene. Early diagnosis of this clinical association is essential since eight of the 11 deaths occurred within a few days after admission. Right-sided thigh emphysema suggests appendicitis, whereas left-sided emphysema is more likely to be secondary to left colonic diverticulitis or carcinoma.

Appendicitis↗

Spiral CT evaluation of pulmonary emphysema using a low-dose technique.

PURPOSE: To evaluate the diagnostic accuracy and clinical acceptability of low-dose spiral CT for determining pulmonary volumes and emphysema extension in patients with pulmonary emphysema, in comparison with studies based on spiral CT at conventional dose. MATERIALS AND METHODS: We prospectively evaluated eighteen patients, current or former smokers, with a clinical diagnosis of chronic obstructive pulmonary disease. All the patients underwent: HRCT with three scans at predetermined levels; quantitative spiral CT, with two inspiratory scans, one conventional scan at 240 mA, and the second one a low-dose scan at 80 mA. We used the following parameters: 120 kV, rotation time 0.8", scan time less than 20" (single inspiratory breath-hold), layer thickness 7.5 mm, pitch 6 (high speed), interpolation algorithm at 180 degrees. A 3D reconstruction was performed, with segmentation of the lungs and automatic quantification of pulmonary volumes. We compared the volumes of absolute and percent emphysema and the ratings of the dose delivered to the patient (CTDIw and DLP) obtained with the two spiral CT scans with each other and with the respiratory function tests. RESULTS: The average total lung capacity (TLC) obtained by conventional-dose spiral CT (CTs1) was 6889.4 cc (SD +/-1813.2), and the capacity with low-dose spiral CT (CTs2) was 6929.4 cc (SD +/-1811.6). The percentage of emphysema was 39.7% (range: 2.2-63.5%; SD: +/-19.9) for the CTs1 and 41.1% (range: 2.1-66.4%; SD: +/-20). The CTDIw corresponding to CTs1 was 12.2 mGy (range: 11.9-16.4; SD: +/-1), the one corresponding to CTs2, 3.6 mGy (range: 3.6-4.9; SD: +/-0.3). The DLP corresponding to CTs1 was 391.7 mGy x cm (range: 333.3-518.9; SD: +/-46.7), the one corresponding to CTs2 was 117.8 mGy x cm (range: 100.3-156; SD: +/-14). As for the respiratory function tests, the total lung capacity (TLC) obtained by body plethysmography was 7061 cc (SD: +/-2029.7); the percent TLC was 115.9 (range: 66-165; SD: +/-27.6), the forced expiratory volume at one second (FEV1%, percentage of predicted value) was 46.7% (range: 17-123; SD: +/-27.3), residual volume (RV%) as a percentage of predicted value was 186.3 (range: 84-359; SD: +/-80.7), the Tiffeneau index (TI) was 46% (range: 25-71; SD: +/-15.7). We observed a very significant correlation between radiological and functional TLC for both CT methods. The percentage scores for emphysema obtained with the two methods correlated significantly with the functional indexes. The pixel index of CTs1 correlated with TLC% (r=0.87; p<0.0001), FEV1% (r=-0.53; p<0.02), RV% (r=0.76; p=0.004), TI (r=-0.79; p=0.0001). The pixel index of CTs2 correlated with TLC% (r=0.87; p<0.0001), FEV1% (r=-0.56; p=0.01), RV% (r=0.78; p=0.003), TI (r=-0.8; p=0.0001). The adoption of the method with low tube current entailed a highly significant reduction in the estimated dose delivered to patients (CTDIw and DLP) with r=0.9 and p < 0.0001. DISCUSSION AND CONCLUSIONS: Quantitative low-dose spiral CT is a very good method to quantify pulmonary volumes and calculate the extension of the anatomic emphysema. The reduction of mA from 240 to 80 lowers the estimated dose by 30%, without compromising the accuracy of the results. Our study achieved a highly significant correlation between the results obtained with the two spiral CT techniques and between these results and the respiratory function tests. In clinical practice, the easiest way to reduce the dose in spiral CT of the lung is to reduce the tube current. The low-dose method allows a significant reduction in radiation exposure. Further studies are required to establish to what extent the dose can be reduced without increasing in quantum noise and thereby compromising the quality of the study.

Adult↗

CT quantification of pulmonary emphysema: assessment of lung structure and function.

Accurate diagnosis and quantification of pulmonary emphysema in vivo is important to understand the natural history of the disease, to assess the extent of the disease, and to evaluate and follow-up therapeutic interventions. Because pulmonary emphysema is defined by pathology, new diagnostic methods for quantification should be validated by reference to pathological and histological standards. Recent studies have addressed the capability of computed tomography (CT) to accurately quantify pulmonary emphysema. These studies that have been overviewed in this article have been based on CT scans obtained after deep inspiration or expiration, on subjective visual grading, and on objective measurements of attenuation values by using dedicated software providing numerical data on two-dimensional and on three-dimensional approaches, and compared CT data with pulmonary function tests. More recently, fractal and textural analyses were applied to CT scans to assess the presence, extent, and types of emphysema. Quantitative CT has already been used in patient selection for surgical treatment of pulmonary emphysema and in pharmacotherapeutical trials. However, despite numerous and extensive studies already available, this technique has not yet been standardized, and important questions about how to best use CT for the quantification of pulmonary emphysema remain to be addressed.

Age Factors↗

Alpha 1-antitrypsin-deficiency-related emphysema.

BACKGROUND: A congenital cause of emphysema resulting from alpha 1-antitrypsin (A1AT) deficiency affects 1 in 2500 individuals and could account for emphysema in 2 percent of all persons with emphysema. Individuals aged 30 to 45 years with chronic shortness of breath and coughing could have A1AT deficiency. METHODS: Using the key words "alpha 1-antitrypsin deficiency," "chronic obstructive pulmonary disease," and "emphysema," the MEDLINE files were searched from 1985 to the present. Data from articles published before 1985 were accessed from cross-reference of the recent articles. RESULTS AND CONCLUSIONS: Unlike smoker's emphysema, A1AT deficiency is panacinar, appears in middle-aged patients, and is more severe at the lung bases. Chronic bronchitis, mucous hypersecretion, and liver disease, as well as a family history of emphysema, are associated conditions. Clinical management includes the avoidance of smoking and atmospheric pollution. Also available is purified, functional human A1AT in quantities large enough for intravenous replacement or augmentation therapy. Future treatment for the disease includes synthetic elastase inhibitors and an aerosolized formulation of A1AT, which is currently under investigation.

Air Pollution↗

[Expression of pulmonary vascular endothelial growth factor and vascular endothelial growth factor receptor in emphysema].

OBJECTIVE: To investigate the expression of vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor 2 (VEGFR-2/KDR) in lung tissues of emphysema patients. METHODS: The peripheral lung tissues were obtained from 35 patients undergoing pneumonectomy. They were divided into three groups: emphysema group (n = 16), control group (n = 14) and smoking group (n = 5). The level of VEGF protein in lung homogenates was measured by ELISA. The expression of KDR protein in lung was determined by immunohistochemistry, the expression of VEGF and KDR mRNA was detected by reverse transcription polymerase chain reaction, and the apoptosis in lung tissues was observed by terminal transferase dUTP nick end labeling (TUNEL). RESULTS: The level of VEGF protein of emphysema group [(2.77 +/- 1.0) pg/ml] was significantly decreased when compared with control group [(4.51 +/- 1.68) pg/ml, P < 0.01]. The expression of KDR protein, VEGF mRNA and KDR mRNA of emphysema group were lower than those of control group (P < 0.01). The number of TUNEL+ cells in the alveolar septa was significantly increased in the emphysema lungs when compared with the control (P < 0.01). There was no significant difference between smoking group and control group in the expression of VEGF and KDR (P > 0.05). CONCLUSION: The decrease of VEGF and KDR and the increase of alveolar septal cell apoptosis may contribute to the pathogenesis of emphysema.

Aged↗

Subcutaneous emphysema and mediastinitis: unusual complications of tonsillectomy.

INTRODUCTION: Subcutaneous emphysema and mediastinitis are rarely reported complications of tonsillectomy. CASE REPORT: We describe two patients who developed subcutaneous emphysema, one of them with mediastinitis, within a few days after tonsillectomy. The diagnosis was based on the clinical presentation and confirmed by computed tomography (CT). For the patient without mediastinitis, the emphysema disappeared after a short period of reintubation and administration of antibiotics. For the patient with mediastinitis, surgical drainage of a cervico-mediastinal purulent collection was necessary to obtain healing. DISCUSSION: The events leading to subcutaneous emphysema and mediastinitis have not been entirely clarified. They probably include direct introduction of air into the neck via either the tonsillar bed or a laryngeal or pharyngeal wound caused by intubation. The clinical presentation, treatment and possible pathophysiology of subcutaneous emphysema and medisastinits are discussed. CONCLUSION: Emphysema and mediastinitis after tonsillectomy occur seldomly. If rapidly recognised and appropriately managed, mortality can be avoided.

Adult↗

[Correlation between the function and structure in papain-induced emphysema in dogs].

To examine the relationship between morphologic changes and the alteration of pulmonary function, papain solution was administered to 11 dogs by inhalation and to 5 dogs by a single intratracheal injection. Pulmonary function tests, including determination of lung volume subdivision, diffusion capacity (DLCO), pressure-volume relationship of the lung and arterial blood gas were performed before and after papain treatment. The dogs were then killed and the lungs processed for pathologic studies. The severity of emphysema was graded as percent of emphysema according to Dunill's method and we compared this to the antemortem pulmonary function data. Exponential constant K was determined by fitting lung pressure-volume data to the equation V = Vo (1-e-KP). After papain administration, DLCO decreased, K of the pressure-volume curve increased, and arterial blood oxygen pressure reduced significantly. The changes of residual volume, the ratio of residual volume to total lung capacity, DLCO per unit lung volume, and the values of the exponential functions of pressure-volume data were correlated with the severity of emphysema with statistical significance, but none of them showed excellent order correlation. Multiple regression equation using 2 to 4 of the parameters indicated that the severity of emphysema can be predicted more accurately. We conclude that recognition of the severity of emphysema requires a multivariate approach including the determination of lung volume, DLCO, and pressure volume relationship of the lung, because the relationship between the severity of emphysema and the values obtained with these measurements are nonlinear.

Animals↗

Amelioration of human neutrophil elastase-induced emphysema in hamsters by pretreatment with an oligopeptide chloromethyl ketone.

Human neutrophils are a likely source of elastase in the pathogenesis of human pulmonary emphysema. A study was undertaken to determine whether emphysema, induced in hamsters by intratracheal treatment with human neutrophil elastase (HNE), could be ameliorated by intratracheal instillation of succinyl-alanyl-alanyl-prolyl-valine-chloromethyl ketone (CMK). One mg of CMK was given to hamsters 1 h before 300 or 360 micrograms HNE or 1 h or 4 h after 360 micrograms HNE. The animals were studied eight weeks after treatment. The CMK given 4 h after HNE did not ameliorate the emphysema. The CMK given 1 h before HNE, ameliorated the development of emphysema but not bronchial secretory cell metaplasia. A molar ratio of instilled CMK to HNE of 128 was required for 50% in vivo effectiveness in ameliorating emphysema. Clearance studies indicated that 6.9% of the instilled CMK could be lavaged from the lungs 1 h after instillation. Therefore, an 8.9 to 1 molar ratio of lavageable CMK to HNE, at the time of HNE instillation, resulted in 50% protection. Using an in vitro assay with 3H-elastin as substrate, a 3 to 1 molar ratio of CMK to HNE was required to inhibit 50% of the elastolytic activity; 14% of the activity remained with an 18 to 1 molar ratio of CMK to HNE. Study of the in vivo effectiveness of anti-elastases, given as pretreatment in ameliorating HNE-induced emphysema and secretory cell metaplasia, is a reasonable bioassay, which may be used as a step in evaluating such agents for possible use in the prevention of human disease.

Animals↗

Large-image intensifier photofluorography and conventional radiography in pulmonary emphysema. Correlation with computed tomography.

Large-screen image intensifier (II) photofluorography was compared with full-size screen-film chest radiography in the diagnosis of pulmonary emphysema in 84 patients. Photospot films and conventional radiographs were interpreted independently by three radiologists. Computed tomography (CT) was used as an independent reference technique, and diagnostic performance of chest radiography in various CT patterns of emphysema was evaluated. The difference in diagnostic sensitivity for emphysema in favor of conventional chest radiography over photofluorography (0.65 versus 0.56) was statistically significant (p less than 0.05). Specificity of the imaging modalities was equal: 0.78 in full-size films and 0.77 in photospot films. All CT patterns of emphysema had great false negative response rates in chest radiography, which is an inaccurate technique for the diagnosis of emphysema. CT is required for reliable radiologic evaluation of emphysema.

Emphysema↗

Effects of intravenous prostaglandins F2 alpha and E2 in hypoxic and non-hypoxic rabbits with elastase induced emphysema.

To determine whether the pulmonary and circulatory effects of intravenous Prostaglandins F2 alpha and E2 are altered in the presence of emphysema and/or hypoxia, 19 New Zealand White rabbits were treated with 3 doses of intratracheal porcine pancreatic elastase (100 U/kg) administered at 4 day intervals to induce panacinar emphysema, and 19 were treated on a similar schedule with saline to serve as controls. Thirty days after their last elastase or saline treatment, rabbits were divided randomly into hypoxic and non-hypoxic breathing subgroups, so that there were 4 experimental groups: control/non-hypoxic (n = 10), control/hypoxic (n = 9), elastase/non-hypoxic (n = 11), and elastase/hypoxic (n = 8). All rabbits underwent pulmonary physiologic studies and received rapid intravenous infusions of PGF2 alpha (6, 12, 14 micrograms) and PGE2 (1,3,6 micrograms). Lung resistance (RL), dynamic lung compliance (Cdyn), right ventricular systolic pressure (Prv), and mean aortic pressure (Paorta) were measured before, and 1 and 5 min. after prostaglandin infusions. At the conclusion of these studies, all rabbits were killed for morphometric and light microscopic analysis of their lungs. Elastase treated rabbits and physiologic, morphometric, and light microscopic evidence of panacinar emphysema. In the control/non-hypoxic group, PGF2 alpha had no effect on Cdyn, but produced a decline in Paorta and an increase in RL and Prv after the 24 micrograms dose. In the same group, PGE2 had no effect on RL or Cdyn, but a decrease in Paorta was observed with all 3 doses. In addition, Prv increased after 6 micrograms of PGE2. These effects were produced by doses of PGF2 alpha and PGE2 which were 12 and 3 times greater respectively than effects of similar magnitude in dogs. Except for the absence of an increase in RL after PGF2 alpha 24 micrograms, the presence of emphysema did not alter the effects of PGF2 alpha or PGE2. However, hypoxia irrespective of emphysema produced greater physiologic effects from both prostanoids. These findings indicate that rabbits are more resistant to the effects of PGF2 alpha and PGE2 on pulmonary mechanics, and pulmonary and systemic vascular pressures. Furthermore, they suggest that hypoxia is a more important factor influencing pulmonary prostaglandin catabolism than anatomic pulmonary emphysema.

Animals↗