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Biomedical subjects

J D Cooper

Publications and source records attributed to J D Cooper.

At least 127 records · Page 7Linked to original sources
PubMed1996

[Bilateral volume reduction for surgical treatment of advanced lung emphysema].

Lung volume reduction (LVR) for advanced emphysema improves lung function and restores respiratory excursion of chest wall and diaphragm. Between January 1993 and February 1996, bilateral LVR via sternotomy was performed in 150 patients with an early mortality (< 60 days) of 2% (3/150). In 90 patients, FEV1 rose from 0.7 (24% pred.) preoperatively to 1.1 L (37% pred.) at 6 months (57% increase; p < 0.001). In the same interval, O2 requirements decreased during exercise from 95 to 46% of patients and from 50 to 16% of patients on continuous O2. After 1 (n = 54) and 2 (n = 15) years, the improvements in FEV1, pO2, 6-min walking distance, and dyspnea, and the reduction of TLC and RV remained stable. In selected patients, bilateral LVR results in marked improvement of emphysema-related disability and offers excellent palliation.

Carbon Dioxide↗
PubMed1995

Single lung transplantation for pulmonary hypertension. Single institution experience in 34 patients.

BACKGROUND: The present study considered the uniformity and durability of the cardiopulmonary response to single lung transplantation in patients with severe pulmonary hypertension, as well as its effect on length and quality of survival. METHODS AND RESULTS: Thirty-four patients with pulmonary hypertension underwent evaluation, single lung transplantation, and follow-up assessment between November 1, 1989, and June 1, 1994. Operative survival for the entire group of patients was reasonable, with 91% (31 of 34 patients) surviving and being discharged from the hospital following transplantation. The actuarial survival for these 34 patients at 1-, 2-, and 3-year follow-up was 78%, 66%, and 61%, respectively. In the subgroup of 24 patients with primary pulmonary hypertension (PPH), 96% (23 of 24) were successfully discharged from the hospital after transplantation. The actuarial survival for this isolated PPH subgroup at 1-, 2-, and 3-year follow-up was 87%, 76%, and 68%, respectively. The uniform, early posttransplant normalization of pulmonary vascular resistance and right ventricular ejection fraction appears to persist throughout the 4-year follow-up period. Despite a high prevalence of bronchiolitis obliterans, the majority of survivors remain in New York Heart Association functional class I or II and are employed. CONCLUSIONS: Single lung transplantation can be performed in patients with end-stage pulmonary vascular disease with reasonable expectations for a relatively low operative mortality; immediate, complete, and durable amelioration of pulmonary hypertension and right ventricular failure; and optimal use of limited donor organ supply.

Actuarial Analysis↗
PubMed1995

Internal fixation of high tracheal stents.

A technique for internal fixation of a silicone elastomer tracheal stent is described. This technique allows the use of a short stent in situations where complex stent placement otherwise would be necessary. The procedure was used successfully to manage a postresection stricture in the subglottic trachea.

Adult↗
PubMed1995

Immunostains for blood group antigens lack prognostic significance in T1 lung carcinoma.

Recent reports have suggested that the retention of blood group antigen expression on tumor cells may be an important prognostic factor for survival. From 1986 to 1991, 136 patients underwent operative resection for their T1 N0 non-small cell lung carcinoma. One hundred twenty tissue blocks were available for antigen testing, and the histologic types were as follows: adenocarcinoma (73 patients), squamous cell (39 patients), large cell/undifferentiated (7 patients), and mucoepidermoid (1 patient). Follow-up is complete for all patients (mean, 41 months). This distribution of patients among the blood groups was as follows: A, 56 (47%); O, 53 (44%); B, 9 (7.5%), and AB, 2 (1.7%). Immunostaining was performed for A, B, and H blood group antigens. The 5-year actuarial survival in the blood group A patients (53%) did not differ significantly from that in the blood group O patients (59%). Similarly, when tumors were examined for their respective antigens, no significant differences were found in the 5-year survival of either blood group A or O patients between the tumors that retain and those that lose blood group antigen expression. Retention or loss of blood groups A or O antigen expression does not predict survival in patients with early-stage lung carcinomas.

ABO Blood-Group System↗
PubMed1995

Pressure gradient across the pulmonary artery anastomosis during lung transplantation.

BACKGROUND: Perioperative monitoring of pulmonary artery (PA) pressures in lung transplant recipients is critical. This report characterizes an intraoperative gradient across the PA anastomosis in a series of patients undergoing bilateral sequential lung transplantation. METHODS: Hemodynamic measurements were obtained in a series of 10 patients before anesthetic induction, during one-lung ventilation/perfusion of the newly transplanted first lung with the PA catheter proximal and distal to the anastomosis and after arrival in the intensive care unit. The following measurements were recorded: central venous pressure, cardiac output, PA occlusion pressure, and systemic and pulmonary arterial pressures (systolic, diastolic, mean). RESULTS: Although a systolic pressure gradient of more than 10 mm Hg across the anastomosis was observed in all patients, there was a significant variation in systolic (13 to 59 mm Hg), diastolic (2 to 10 mm Hg), and mean (5 to 27 mm Hg) PA gradients. Mean proximal systolic PA pressure measurements (56.2 +/- 20.6 mm Hg) were greater when compared to measurements obtained distal to the anastomosis (28.6 +/- 10.1 mm Hg, p = 0.001) and to those obtained in the postoperative period (32.1 +/- 9.7 mm Hg, p = 0.004). CONCLUSIONS: The present study demonstrates that during single-lung ventilation and perfusion, the PA pressure measured proximally may not reflect accurately the pressure distal to the vascular anastomosis.

Anastomosis, Surgical↗
PubMed1995

Effect of ischemic injury on subsequent rat lung allograft rejection.

BACKGROUND: It has been suggested that the frequency and severity of allograft rejection may be related to the degree of allograft ischemia. The purpose of this study was to determine whether ischemic insult correlates with lung allograft rejection. METHODS: Forty-eight left lung transplants were performed from Lewis donor rats into F344 recipient rats. Allografts were divided into two groups based on the degree of ischemic insult. Transplantation was performed immediately (group 1, minimum injury) or after 18 hours of cold (1 degree C) preservation (group 2, severe injury). Allografts were evaluated radiographically based on aeration scores (0 = opaque to 6 = normal). Animals were randomly sacrificed on days 7, 14, or 21 for histologic and immunohistochemical evaluation of rejection. RESULTS: On postoperative day 3, significantly lower aeration score was demonstrated in group 2 (3.69 +/- 1.71) compared to group 1 (5.0 +/- 1.09) (p < 0.05) as a result of the difference in reperfusion injury. However, by day 7 and thereafter, there was no significant difference. Histologic rejection was present by day 7 and peaked at day 14 with no significant difference between groups. There was also no difference in CD4+, CD8+ infiltrating lymphocyte population or expression of class II major histocompatibility complex antigen on bronchial epithelium. CONCLUSIONS: We conclude that ischemic injury in rat lung allograft does not correlate with the onset or severity of rejection.

Animals↗
PubMed1995

Free radical-mediated vascular injury in lungs preserved at moderate hypothermia.

BACKGROUND: Early allograft dysfunction remains a frequently encountered problem in clinical lung transplantation. Lung ischemia-reperfusion injury is associated with increased vascular permeability, which may be due in part to oxygen (O2) free radicals. However, it is not clear whether O2 free radicals are produced during ischemia under storage conditions in clinical lung transplantation. METHODS: Using an isolated ex vivo rabbit lung model, we studied the effects of preservation temperature on pulmonary capillary filtration coefficient (Kf) and lipid peroxidation in rabbit lungs inflated with 100% O2 after preservation with or without the O2 free radical scavenger dimethylthiourea. New Zealand white rabbits weighing 2.7 to 3.1 kg were intubated and ventilated with room air or 100% O2 (tidal volume = 25 mL). After heparinization and sternotomy, the pulmonary artery was flushed with low-potassium-dextran-1% glucose solution (200 mL). The heart-lung block was excised, submerged, and stored for 24 hours at 1 degree or 10 degrees C. After 24-hour preservation, the heart-lung block was suspended from a strain-gauge force transducer and ventilated with room air. The pulmonary artery cannula was connected to a reservoir of hetastarch solution. The lungs were flushed briefly with the hetastarch solution, and the reservoir was raised sequentially at 8-minute intervals to achieve 1.0 to 1.5 mm Hg increments in pulmonary artery pressure. Lung weight gain, airway pressure, pulmonary artery pressure, and left atrial pressure were measured continuously. The slope of steady-state lung weight gain was used to determine Kf (g.min-1.cm H2O-1 x 100 g-1 wet weight). RESULTS: Twenty-four-hour lung preservation at both 1 degree and 10 degrees C increased Kf. A similar increase in Kf was observed in lungs stored at 1 degree C while inflated with 100% O2. However, a significant increase in Kf was observed when lungs inflated with 100% O2 were stored at 10 degrees C. This increase in Kf was ameliorated by dimethylthiourea. Thiobarbituric acid-reactive substance levels were increased in lungs stored at 10 degrees C while inflated with 100% O2. This finding was eliminated by dimethylthiourea. CONCLUSIONS: These results indicate that free radical injury occurs during the ischemic phase when lungs are stored at moderate hypothermia while inflated with 100% O2.

Animals↗
PubMed1995

Prevalence and outcome of bronchiolitis obliterans syndrome after lung transplantation. Washington University Lung Transplant Group.

BACKGROUND: Bronchiolitis obliterans syndrome (BOS) is the main cause of late morbidity and mortality in lung transplantation. This study was designed to accurately determine the prevalence of this syndrome of chronic lung allograft dysfunction (which is presumed to be due to chronic rejection). METHODS: A retrospective analysis was done of 212 consecutive lung transplantations performed at Barnes Hospital between July 1988 and March 1994 to characterize the prevalence and course of BOS. One hundred eighty-seven transplant recipients survived at least 3 months after transplantation, putting them at risk for BOS. Recipients free of BOS (group I) were distinguished from those with BOS (group II) based on the presence of declining spirometry (forced expiratory volume in 1 second persistently less than 80% of previous baseline) or histologic obliterative bronchiolitis in group II. RESULTS: There were 110 transplantations in group I (59%) and 77 in group II (41%). At follow-up, BOS was detected using the following criteria: declining forced expiratory volume in 1 second alone, 40 of 77 (52%); positive histologic results alone, 7 of 77 (9.1%); and both, 30 of 77 (38.9%). Declining spirometry was the most common initial sign of BOS onset (57 of 77, 74%). There were no differences between groups with respect to age, sex, indication for transplantation, or type of transplantation performed. The mortality rate was significantly higher with BOS (group II, 22 of 77 [28.6%] versus group I, 8 of 110 [7.3%]; p = 0.001) and was not related to either the type of transplantation performed or the indication for transplantation. Follow-up of group II (mean 35.1 months; range, 7.1 to 63.7 months) showed a delay until BOS onset (16.1 +/- 1.2 months); when BOS was fatal, death ensued within 11.5 +/- 2.4 months of its onset. Comparison of the first and last quartiles of recipients in this series (QTR1 versus QTR4, 53 patients in each) demonstrated a higher prevalence of BOS in QTR1 (24 with BOS of 43 at risk [55.8%] versus QTR4, 5 with BOS of 52 at risk [9.6%]; p < 0.001) and a worse BOS functional score in QTR1 (2.2 +/- 0.2 versus QTR4, 0.8 +/- 0.2; p = 0.007). CONCLUSIONS: (1) Bronchiolitis obliterans syndrome is truly a clinical syndrome, not simply a pathologic entity; (2) BOS displays considerable latency in onset and progression; (3) lung transplant recipients must therefore be followed up for a sufficient interval to determine the actual prevalence and mortality rate of BOS; and (4) the prevalence and mortality rates of BOS are higher than previously appreciated, exceeding 50% and 40%, respectively.

Adult↗
PubMed1995

Improved airway healing after lung transplantation. An analysis of 348 bronchial anastomoses.

We evaluated various clinical factors to identify predictors of airway complication after lung transplantation. Two hundred twenty-nine consecutive single (n = 110) and bilateral (n = 119) lung transplants were done between September 1988 and August 1994. These 348 bronchial anastomoses were retrospectively analyzed. Airway complication that necessitated clinical intervention affected 33 anastomoses (9.5%) in 29 patients (12.8%). Satisfactory healing was achieved in 22 of these patients by conservative therapy such as one or a combination of dilation, stent, and laser. There were five deaths (2.2%) attributable to airway complications. One patient had an early postoperative death unrelated to airway complication and one patient has a recalcitrant bronchus intermedius stricture. Complication occurred more often in single-lung than in bilateral lung transplants (16/110, 14.4%, versus 17/238, 7.1%; p < 0.05). The use of a mattress suture (21/153, 13.7%) was associated with more frequent complications than was simple interrupted suture (8/122, 6.6%) or figure-of-eight suture (4/73, 5.5%) (p < 0.05). For patients in whom airway complications subsequently developed, the duration of postoperative mechanical ventilation was greater than that for those in whom an airway complication did not develop. The prevalence of airway complications as our program evolved was evaluated by separating the 229 transplants into three groups: phase I, the first 77 transplants; phase II, the next 76 transplants; and phase III, the most recent 76 transplants. The airway complication rate per anastomosis was significantly lower in phase III (5/126, 4.0%) than in phase I (12/110, 10.9%; p < 0.05) and phase II (16/112, 14.3%; p < 0.01). The majority of airway complications are successfully treated and rarely fatal. The recent reduction in prevalence of airway complications is likely a result of better maintenance immunosuppression and rejection surveillance.

Adult↗
PubMed1995

Inhibition of inducible nitric oxide synthase ameliorates rat lung allograft rejection.

Recently, the inducible isoform of nitric oxide synthase has been shown to be an important immunomodulation molecule in allograft rejection. We have observed the production of nitric oxide during rejection and the effect of nitric oxide synthase inhibition on allograft rejection in a rat lung transplant model. Rat left lung allotransplants were performed in two strain combinations: brown Norway-to-F344 (major histocompatibility complex incompatible); and Lewis-to-F344 (minor loci incompatible) as severe and mild rejection models respectively. Syngeneic F344-to-F344 transplants were performed as a negative control. Nitric oxide production during rejection was determined by measuring the recipient's serum nitrite/nitrate levels as a stable end product of nitric oxide. The progression of rejection was evaluated radiographically and the grade of rejection was determined histologically. After operation, recipients of allotransplantation were randomly divided into two groups and received either aminoguanidine (200 mg/kg, intraperitoneal every 6 hours), a potent inducible nitric oxide synthase inhibitor, or normal saline treatment. The levels of serum nitrite and nitrate in recipients increased in the early phase of rejection in both allotransplant combinations. However, in the terminal phase of rejection, the serum nitrite/nitrate level decreased significantly compared with the peak level in the brown Norway-to-F344 recipients. The serum nitrite/nitrate levels in the syngeneic transplant recipients were normal during the entire observation period. In aminoguanidine-treated animals, serum nitrite/nitrate levels remained normal in both allograft combinations. Significant suppression of rejection in aminoguanidine-treated recipients was observed histologically and radiographically in comparison with untreated recipients in the brown Norway-to-F344 combinations. In the Lewis-to-F344 combination, aminoguanidine treatment significantly ameliorated histologic rejection but did not affect radiologic appearance. We therefore conclude nitric oxide is produced during early allograft rejection and may prove to be a marker and mediator of early rejection. The inhibition of inducible nitric oxide synthase results in significant reduction in rat lung allograft rejection.

Animals↗
PubMed1995

Successful outcome of lung transplantation is not compromised by the use of marginal donor lungs.

Lung transplantation is limited by a shortage of suitable donors. To address this shortage, we have begun using donor lungs that do not meet all of our previous rigorous donor criteria. Of 133 consecutive lung transplants done between June 1991 and March 1994, 89 donors were considered ideal because they satisfied all of the following accepted donor criteria (group I): age younger than 55 years, smoking less than 20 pack-years, arterial oxygen tension greater than 300 mm Hg (using inspired oxygen fraction of 1.0 and positive end-expiratory pressure 5 cm H2O), and chest radiograph negative for infiltrate or trauma (contusion or pneumothorax). Thirty-seven donors failed to satisfy one of these criteria and seven donors failed to satisfy two of them, yielding 51 criteria denoting marginal status in the 44 donors in the marginal group (group II) as follows: age older than 55 years, 2; smoking history 20 or more pack-years, 9; unsatisfactory chest radiograph, 34; and arterial oxygen tension less than 300 mm Hg, 6. Sixty-three single lung transplants were done (group I, 44 versus group II, 19) compared with 70 bilateral sequential transplants (group I, 45 versus group II, 25). In 24 cases in group II, at least one of the lungs actually being implanted contained contusion or infiltrate. Evaluation of recipients from the two groups showed no significant difference in median duration of postoperative mechanical ventilation (3 days in both group I and group II) nor in alveolar-arterial oxygen gradient immediately after transplantation (group I, 304 +/- 14 mm Hg versus group II, 275 +/- 22 mm Hg; p = 0.266) or at 24 hours (group I, 125 +/- 12 mm Hg versus group II, 122 +/- 18 mm Hg; p = 0.933) (all values represent mean plus or minus the standard error). However, cardiopulmonary bypass was required to facilitate second graft insertion in bilateral sequential transplants more often in the marginal group (5 of 25, 20%) than in group I (6 of 45, 13%). There were three deaths within 30 days in group I (operative mortality, 3.4%) and none in group II. Currently, 74 (83.2%) of 89 remain alive in group I compared with 38 (86.4%) of 44 in group II. On the basis of these data, we conclude that successful outcome of lung transplantation can be achieved with the use of marginal donor lungs.

Age Factors↗
PubMed1995

Bilateral pneumectomy (volume reduction) for chronic obstructive pulmonary disease.

We undertook surgical bilateral lung volume reduction in 20 patients with severe chronic obstructive pulmonary disease to relieve thoracic distention and improve respiratory mechanics. The operation, done through median sternotomy, involves excision of 20% to 30% of the volume of each lung. The most affected portions are excised with the use of a linear stapling device fitted with strips of bovine pericardium attached to both the anvil and the cartridge to buttress the staple lines and eliminate air leakage through the staple holes. Preoperative and postoperative assessment of results has included grading of dyspnea and quality of life, exercise performance, and objective measurements of lung function by spirometry and plethysmography. There has been no early or late mortality and no requirement for immediate postoperative ventilatory assistance. Follow-up ranges from 1 to 15 months (mean 6.4 months). The mean forced expiratory volume in 1 second has improved by 82% and the reduction in total lung capacity, residual volume, and trapped gas has been highly significant. These changes have been associated with marked relief of dyspnea and improvement in exercise tolerance and quality of life. Although the follow-up period is short, these preliminary results suggest that bilateral surgical volume reduction may be of significant value for selected patients with severe chronic obstructive pulmonary disease.

Adult↗
PubMed1995

Quantitative analysis of cytomegalovirus viremia in lung transplant recipients.

A quantitative culture method was used to test serial blood specimens from 28 lung transplant recipients at risk of cytomegalovirus (CMV) infection (donor [D] or recipient [R] seropositive for CMV). Viremia occurred in 26 (93%) of 28 patients. Highest levels were seen when the donor was seropositive. The median of individual maximum levels was 2.13 infectious centers (ICs/10(5) leukocytes for D+/R- patients (interquartile range [iqr], 0.12-21.77), 1.01 for D+/R+ (iqr, 0.3-2.32), and 0.10 for D-/R+ (iqr, 0.07-0.36; P = .030, Kruskal-Wallis test). Higher levels were seen in patients with biopsy-proven CMV pneumonitis compared with those with negative biopsies (mean, 0.24 [SD 0.51] ICs/10(5) leukocytes vs. 0.01 [SD 0.03]; P = .039, Wilcoxon test) and with symptomatic CMV episodes compared with asymptomatic episodes (median, 0.34 ICs/10(5) [iqr, 0.11-0.61] vs. 0.08 ICs/10(5) [iqr, 0.03-0.13]; P = .045, Wilcoxon test). Further studies are required to determine whether quantification of CMV viremia by this method will be of practical value in the recognition of significant CMV infection in lung transplant recipients.

Antigens, Viral↗
PubMed1995

Bronchial dehiscence in lung transplantation: CT evaluation.

PURPOSE: To determine the signs of bronchial dehiscence on computed tomographic (CT) scans in a select subset of lung transplant recipients. MATERIALS AND METHODS: In 23 patients who underwent single or bilateral sequential lung transplantations, CT scans were obtained for suspected or known diagnosis of bronchial dehiscence. Dehiscence was identified at bronchoscopy in 17 of the 23 patients. In four patients, the dehiscence was bilateral, resulting in 21 anastomotic dehiscences. RESULTS: CT allowed identification of a bronchial defect in 100% of the bronchoscopically proved dehiscences but only one (5%) of the 18 bronchoscopically proved intact anastomoses. CT also demonstrated extraluminal air in 100% of the bronchoscopically proved dehiscences. Only a very small amount of extraluminal air (without associated bronchial defect) was identified on CT scans in the early postoperative period in four additional patients with bronchoscopically proved intact anastomoses. CONCLUSION: CT is an easily performed and well-tolerated technique that has a high degree of sensitivity and specificity for depicting bronchial dehiscence.

Adolescent↗
PubMed1995

Lung transplant edema: chest radiography after lung transplantation--the first 10 days.

PURPOSE: To determine the imaging spectrum and clinical correlates of lung transplant edema within the first 10 days after lung transplantation. MATERIALS AND METHODS: The study group consisted of 105 consecutive lung transplant recipients. Lung infiltrates on chest radiographs were scored and characterized. Findings that satisfied the accepted description of reperfusion edema were identified. Lung ischemia times and the clinical or biopsy diagnosis of acute rejection were correlated with radiographic findings. RESULTS: Lung infiltrates compatible with reperfusion edema were seen in 97% of transplanted lungs without a demonstrable correlation with lung ischemia times. Lung scores between groups of patients treated and not treated for acute rejection were not statistically significantly different. CONCLUSION: The spectrum of findings attributable to lung transplantation or reperfusion edema is variable and diminishes the use of chest radiography as an early postoperative modality for monitoring acute rejection.

Adult↗
PubMed1995

Expression of class II major histocompatibility complex antigens (HLA-DR) and lymphocyte subset immunotyping in chronic pulmonary transplant rejection.

OBJECTIVE: Currently, the bronchiolitis obliterans syndrome (BOS) of chronic airway rejection represents the most significant obstacle to the long-term function of isolated pulmonary allografts in humans. Between 20% and 30% of recipients are affected by this condition. To define the possible pathogenetic role of altered expression of class II major histocompatibility complex antigens (ie, HLA-DR) in BOS, the authors studied well-characterized examples of this process immunohistologically. DESIGN: Eleven BOS specimens were compared with seven controls, represented by allografts with no pathologic abnormalities taken from patients with normal posttransplant respiratory function, as well as 14 biopsies showing acute rejection. In addition, immunophenotypic subtyping of lymphocytes in all specimens was undertaken. RESULTS: Control tissues exhibited variable but weak expression of HLA-DR in bronchiolar epithelium and alveolar pneumocytes. In comparison, immunostaining for class II major histocompatibility complex antigens in BOS showed no statistically significant differences, whereas the 14 examples of acute rejection manifested intense HLA-DR expression in epithelia and endothelial cells. The numbers of intrabronchiolar and peribronchiolar lymphocytes were clearly higher in both acute rejection and BOS than in controls, but these cells differed in lineage in the two rejection states. Acute rejection showed an obvious preponderance of CD43-positive T lymphocytes, whereas lymphoid cells in BOS were a relatively equal mixture of CD20-positive B cells and CD43-positive T cells. Moreover, incipient peribronchiolar B-cell follicles were observed in BOS. Natural killer (CD57-positive) lymphocytes were rare in all specimens. CONCLUSIONS: These data suggest that alterations in HLA-DR expression probably do not play a central role in the genesis of BOS, as they do in acute rejection. In contrast, the results of lymphocyte immunophenotyping and correlative histologic findings in BOS suggest that both T cells and B lymphocytes may be involved in the mechanism of chronic airway rejection.

Adult↗
PubMed1995

Lung-volume reduction surgery for severe emphysema.

The lung-volume reduction procedure is a palliative one, designed to relieve dyspnea, and improve the patient's ability to carry out routine activities of daily living without significant limitations. The rationale for this procedure and its development are discussed. In addition, patient selection, operative technique, postoperative care, results, and complications are considered. Ultimately, the value of lung-volume reduction surgery will be determined by the balance between the magnitude and duration of benefit achieved on the one hand versus the morbidity and mortality produced on the other.

Humans↗