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Biomedical subjects

V F Tapson

Publications and source records attributed to V F Tapson.

At least 37 records · Page 2Linked to original sources
PubMed1999

Continuous infusion of epoprostenol improves the net balance between pulmonary endothelin-1 clearance and release in primary pulmonary hypertension.

BACKGROUND: Primary pulmonary hypertension results from progressive narrowing of the precapillary pulmonary vasculature. A variety of endothelial abnormalities have been identified, including a net reduction in pulmonary clearance of the vasoconstrictor and smooth muscle mitogen endothelin-1. In many patients, net pulmonary release of endothelin-1 is observed. Chronic infusions of epoprostenol (prostacyclin) improve functional capacity, survival, and hemodynamics in patients with advanced primary pulmonary hypertension. We hypothesized that the epoprostenol infusions, as compared with conventional therapy, might alter the abnormal pulmonary endothelin-1 homeostasis. METHODS AND RESULTS: Using a subset of patients from a larger randomized study comparing epoprostenol plus conventional therapy (n=11 in the present study) with conventional therapy alone (n=7 in the present study), we determined the ratio of plasma endothelin-1 levels in systemic arterial blood leaving the lung to levels in mixed venous blood entering the lung both before randomization and after 88 days of continuous therapy. There were no differences between the 2 groups before therapy, but by day 88, the epoprostenol-treated group had a greater proportion of patients (82%) with an arterial/venous ratio <1 than did the conventional therapy group, in which only 29% of patients had a ratio <1 (P<0.05). CONCLUSIONS: These results suggest that continuous epoprostenol therapy may have a beneficial effect on the balance between endothelin-1 clearance and release in many patients with primary pulmonary hypertension and may provide one explanation for the salutary effect of epoprostenol in this disease.

Antihypertensive Agents↗
PubMed1999

Cystic fibrosis: usefulness of thoracic CT in the examination of patients before lung transplantation.

PURPOSE: To evaluate the usefulness of thoracic computed tomography (CT) in the pre-lung transplantation examination of patients with cystic fibrosis (CF). MATERIALS AND METHODS: Fifty-six patients (age range, 12-42 years) with CF were evaluated for possible lung transplantation from 1991 to 1997. Twenty-six of these patients underwent bilateral lung transplantation, 19 were awaiting transplantation at the time of the study, seven died before transplantation, and four were excluded for psychosocial concerns. Preoperative chest radiographic and CT findings were reviewed and correlated with clinical, operative, and pathology records. RESULTS: In seven patients, discrete, 1-2-cm pulmonary nodules were detected at CT. Five of these patients underwent transplantation; the nodules were found to be mucous impactions. No malignancy was found in any of the patients who underwent transplantation. Pretransplantation sputum cultures grew Aspergillus fumigatus in seven patients, none of whom had radiologic findings suggestive of Aspergillus infection. Radiographic or CT findings were suggestive of mycetoma in five cases, but no such tumors were found at transplantation. The accuracies of chest radiography and CT for the detection of pleural disease in 48 hemithoraces were 81% (n = 39) and 69% (n = 33), respectively. The radiologic findings of pleural thickening did not influence the surgical approach in any patient. CONCLUSION: Thoracic CT has little utility in the routine pre-lung transplantation examination of patients with CF.

Adolescent↗
PubMed1999

Respiratory viral infections in lung transplant recipients: radiologic findings with clinical correlation.

PURPOSE: To evaluate radiologic finding of respiratory viral infection in lung transplant recipients with clinical correlation. MATERIALS AND METHODS: Over 5 years, 21 episodes of respiratory viral infection (parainfluenza [n = 9], respiratory syncytial virus [n = 8], adenovirus [n = 5], influenza [n = 2]) were diagnosed 6-727 days (mean, 270 days) after lung transplantation in 20 recipients. Chest radiographs, computed tomographic (CT) images, and clinical records were reviewed. RESULTS: Sixteen episodes of respiratory viral infection were diagnosed in patients with symptoms of lower respiratory tract infection or acute allograft dysfunction; five were diagnosed in asymptomatic patients. Chest radiographs were abnormal in 11 (52%) episodes; findings included heterogeneous or homogeneous opacities and masslike consolidation. All patients with radiographic abnormalities were symptomatic. Chest radiographs were unchanged from baseline in 10 (48%) episodes; in one, CT revealed findings not depicted at radiography. Adenoviral infection (n = 5) was typically symptomatic, was associated with new radiographic abnormalities, and was rapidly lethal (n = 4). Infection with parainfluenza and/or respiratory syncytial virus was commonly asymptomatic and was not associated with radiographic abnormalities; affected patients had good outcomes. CONCLUSION: Respiratory viral infections are important causes of morbidity and mortality in lung transplant recipients. Radiographic abnormalities in patients with respiratory viral infections were usually accompanied by symptoms of lower respiratory tract infection. Adenoviral infection was frequently accompanied by progressive pulmonary opacity and fatal outcome.

Adenovirus Infections, Human↗
PubMed1999

Rabbit antithymocyte globulin decreases acute rejection after lung transplantation: results of a randomized, prospective study.

STUDY OBJECTIVES: The efficacy of antithymocyte induction therapy in lung transplantation is controversial, and its use varies from center to center. We hypothesized that rabbit antithymocyte globulin (RATG) induction therapy would decrease acute rejection after lung transplantation, and we designed a single-center, randomized, prospective study to test this hypothesis. DESIGN: A total of 44 single or bilateral adult lung transplant recipients were randomly assigned to receive either RATG induction therapy (dosage, 1.5 mg/kg/d for 3 days) at the time of transplantation, along with conventional immunosuppression (cyclosporine, azathioprine, and prednisone), or conventional immunosuppression alone with no induction therapy. RESULTS: Although a similar number of biopsies were performed in each group, the number of patients experiencing biopsy-proven grade II or greater acute rejection was significantly reduced in the group receiving RATG induction therapy (23% incidence), as compared to the patients treated with conventional immunosuppression alone (55% incidence; p = 0.03). In addition, there was a nonsignificant reduction in the incidence of bronchiolitis obliterans syndrome at the conclusion of the study in patients who received RATG induction (20%), as compared to patients in the control group (38%). The incidence of posttransplant infections and malignancies were similar between the two groups. CONCLUSION: Induction therapy with RATG significantly reduces the incidence of acute allograft rejection after lung transplantation.

Acute Disease↗
PubMed1999

Pulmonary cholesterol granulomas in patients with pulmonary artery hypertension: chest radiographic and CT findings.

OBJECTIVE: We describe the chest radiographic and CT findings of pulmonary cholesterol granulomas in patients with pulmonary artery hypertension. CONCLUSION: Histopathologic evidence of cholesterol granulomas was found in five (25%) of 20 patients with severe pulmonary hypertension. In three of these five patients, the granulomas manifested on chest radiographs and CT as small centrilobular nodules mimicking the appearance of sarcoidosis, bronchiolitis, hypersensitivity pneumonitis, or aspiration.

Adult↗
PubMed1999

Hyperpolarized 3He-enhanced MR imaging of lung transplant recipients: preliminary results.

OBJECTIVE: Bronchiolitis obliterans syndrome is the major cause of long-term graft failure in lung transplant recipients and may be partially reversible if diagnosed early and treated. Diagnosis is difficult because findings of transbronchial biopsy are often negative in patients with early disease. We are investigating a novel MR ventilation agent, hyperpolarized 3He, for evaluating ventilatory abnormalities in lung transplant recipients with suspected bronchiolitis obliterans syndrome. CONCLUSION: In this preliminary study, the extent of ventilatory defects revealed on 3He-enhanced MR images correlated with severity of bronchiolitis obliterans syndrome using an established clinical grading system. This new technique may hold potential for diagnosing bronchiolitis obliterans syndrome in lung transplant recipients.

Adult↗
PubMed1998

Does hyperexpansion of the native lung adversely affect outcome after single lung transplantation for emphysema? Preliminary findings.

RATIONALE AND OBJECTIVES: The authors evaluated the effect of the native emphysematous lung on graft function after single lung transplantation. MATERIALS AND METHODS: Thirty-two patients who underwent single lung transplantation were examined with radiography preoperatively for degree of emphysema and postoperatively for hyperexpansion of the native lung. All patients underwent ventilation-perfusion scanning before transplantation and ventilation scanning after transplantation. Pulmonary function tests and measurement of arterial partial pressure of oxygen were also measured before and after surgery. The postoperative course was graded on a subjective scale. RESULTS: Hyperexpansion of the native lung was seen in 16 of the 32 patients in the postoperative period. On the basis of serial measurements of forced expiratory volume in 1 minute, these patients fared poorly in the postoperative period compared with patients without hyperexpansion. Pulmonary blood flow to the native lung, as measured with perfusion scintigraphy, paradoxically increased in 11 patients after transplantation. Nine of these 11 patients demonstrated hyperinflation of the native lung, suggesting that graft compression adversely affects blood flow to the transplanted lung. CONCLUSION: Hyperexpansion of the native lung after single lung transplantation for emphysema may have a deleterious effect on graft function and possibly on clinical outcome.

Female↗
PubMed1998

Bronchial anastomotic complications in lung transplant recipients: virtual bronchoscopy for noninvasive assessment.

PURPOSE: To compare the accuracy of virtual bronchoscopy (VB) with that of axial computed tomography (CT) in the assessment of bronchial anastomotic complications in lung transplant recipients. MATERIALS AND METHODS: Twenty-seven bronchial anastomoses in 17 patients were evaluated with helical CT. Axial CT and VB images were evaluated for surface irregularity and the presence, length, and severity of stenosis. Findings were correlated with the results of fiberoptic bronchoscopy (FOB). RESULTS: There were 12 anastomotic stenoses at FOB. Pooled accuracy (among all four readers) of VB and axial CT for diagnosis of clinically relevant stenosis was 97% and 80%, respectively, at the right bronchial anastomoses and 92% and 75%, respectively, at the left bronchial anastomoses. Pooled accuracy of VB and Axial CT for stenosis length was 72% and 62%, respectively, at the right anastomoses and 81% and 69%, respectively, at the left anastomoses. These differences were not statistically significant. Both the VB and axial CT images showed surface irregularities when anastomotic infection (n = 2) or dehiscence (n = 1) was present but resulted in an overdiagnosis of mucosal abnormalities when anastomoses were normal. CONCLUSION: VB was slightly more accurate than axial CT for diagnosis of clinically relevant stenoses at bronchial anastomoses in lung transplant recipients. However, because VB is not 100% accurate and has no role in the diagnosis of infection or dehiscence, it probably will not replace FOB for assessment of bronchial anastomotic complications in this population.

Anastomosis, Surgical↗
PubMed1998

Massive pulmonary edema and death after prostacyclin infusion in a patient with pulmonary veno-occlusive disease.

Pulmonary veno-occlusive disease (PVOD) is a rare form of pulmonary hypertension associated with fibrotic occlusion of the smaller pulmonary veins. Although vasodilator therapy is effective in many patients with primary pulmonary hypertension, the role of vasodilators in PVOD is unclear because of concerns about precipitating pulmonary edema. Recently, however, there have been reports of successful therapy with oral vasodilators or intravenous administration of prostacyclin in patients with PVOD. In contrast, a patient with PVOD is described who developed acute pulmonary edema and respiratory failure during low-dose prostacyclin infusion, leading to death. This report suggests that vasodilators, especially prostacyclin, must be used with extreme caution in patients with known PVOD.

Adult↗
PubMed1998

Lung transplantation for Williams-Campbell syndrome.

Williams-Campbell syndrome is a rare disorder characterized by a deficiency of cartilage in subsegmental bronchi leading to distal airway collapse and bronchiectasis. We report the first case of lung transplantation in a patient with end-stage lung disease secondary to Williams-Campbell syndrome. Although the patient did not have proximal airway collapse prior to transplantation, his posttransplant course was complicated by the development of bronchomalacia of the right and left mainstem bronchi. The patient experienced recurrent pulmonary infections and died of bacterial pneumonia 1 year after transplantation. Autopsy revealed cartilage deficiency in both right and left mainstem bronchi. A hypothesis may be made that a combination of proximal cartilage deficiency and posttransplant airway ischemia led to the development of bronchomalacia after lung transplantation. Thus, in contrast to previous reports, the cartilage deficiency in Williams-Campbell syndrome can involve both proximal and distal airways. Consequently, bilateral sequential lung transplantation may not be an effective therapeutic option in patients with this syndrome.

Adult↗
PubMed1998

Community respiratory viral infection in adult lung transplant recipients.

STUDY OBJECTIVE: To define the epidemiology, clinical manifestations, and long-term complications of respiratory viral infections in adult lung transplant recipients. DESIGN: Retrospective review of the records of 122 adult lung transplant recipients over a 5-year period at one institution. RESULTS: Ten episodes of infection with respiratory syncytial virus, parainfluenza, influenza, or adenovirus were identified. All patients presented with symptoms of respiratory tract infection. Two patients died acutely and four patients subsequently had development of obliterative bronchiolitis (OB). CONCLUSIONS: These data suggest community respiratory viral infections cause significant morbidity and mortality in lung transplant recipients. Further prospective studies are warranted to clarify the relationship between respiratory viral infection and OB and to define the optimal therapy for these viral infections.

Adult↗
PubMed1998

Lung transplantation at Duke University Medical Center.

Lung transplantation is a viable therapy for patients with a variety of end-stage lung diseases. Our active program now includes over 200 lung transplant operations with acceptable one- and 3-year survival rates of 78% and 61%. A major focus of clinical research at this institution is to design strategies to prevent the development of chronic allograft dysfunction. Our preliminary work in this regard has been encouraging. In addition, a major research focus has been to design protocols to prevent the development of posttransplant infections. Our work with aerosolized ABLC represents a major advance at our center, and additional randomized prospective studies are ongoing to define the optimal antifungal prophylaxis after transplantation. Ongoing clinical and basic research at Duke and elsewhere should continue to advance the field of clinical transplantation and ultimately lead to more acceptable long-term outcomes for lung allograft recipients.

Adult↗
PubMed1998

Pulmonary rehabilitation in the surgical patient. Lung transplantation and lung volume reduction surgery.

Prior to lung transplantation or lung volume reduction surgery, patients complete a comprehensive pulmonary rehabilitation program. The program aids physicians in the selection of appropriate surgical candidates and prepares patients physically and psychologically for the stress of surgery. Because lung transplantation often involves relocation and prolonged waiting, stress levels can be particularly high. Rehabilitation continues through the perioperative and postoperative period to facilitate recovery and bring patients to the highest possible level of function. Studies of lung transplant recipients suggest that most patients who survive to hospital discharge enjoy a significant improvement in pulmonary function and many resume work and household responsibilities. Initial experiences with lung volume reduction surgery also suggest that many patients experience improved dyspnea symptoms and functional status after the procedure. As lung transplantation and lung volume reduction surgery emerge as viable therapeutic options for many patients with end-stage lung disease, comprehensive pulmonary rehabilitation programs are essential to address the complex medical, surgical, and psychological issues that surround these procedures and to produce optimal therapeutic outcomes.

Humans↗
PubMed1998

Candidal anastomotic infection in lung transplant recipients: successful treatment with a combination of systemic and inhaled antifungal agents.

Anastomotic infection is an uncommon but potentially life-threatening complication after lung transplantation. We recently encountered three lung transplant recipients with invasive candidal anastomotic infection. Two patients were admitted with dyspnea and fever, and one asymptomatic infection was detected on surveillance bronchoscopy. All three patients were treated similarly with a combination of intravenous amphotericin B, inhaled amphotericin B, and oral fluconazole. The combination of systemic and inhaled antifungal agents successfully treated all three cases of anastomotic infection.

Administration, Inhalation↗