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W Klepetko

Publications and source records attributed to W Klepetko.

At least 91 records · Page 5Linked to original sources

Pulmonary retransplantation: does the indication for operation influence postoperative lung function?

OBJECTIVE: An international series of pulmonary retransplantation was updated to determine the factors associated with pulmonary function, bronchiolitis obliterans syndrome stage, and survival after operation. METHODS: One hundred sixty patients underwent retransplantation in 35 centers from 1985 to 1995. Logistic regression methods were used to determine variables associated with 3-month and 2-year survival after retransplantation. Values of forced expiratory volume in 1 second were contrasted between groups by unpaired, two-tailed t tests. RESULTS: The median follow-up in surviving recipients was 780 days. Actuarial survival was 45% +/- 4%, 41% +/- 4%, and 33% +/- 4% at 1, 2, and 3 years, respectively. On multivariable analysis, the only predictor of 3-month survival was preoperative ambulatory status (p = 0.005), whereas center experience with at least five pulmonary retransplantations was the sole predictor of 2-year survival (p = 0.04). The prevalence of stage 3 (severe) bronchiolitis obliterans syndrome was 12% at 1 year, 15% at 2 years, and 33% at 3 years after retransplantation. Retransplant recipients with stage 3 bronchiolitis obliterans syndrome at 1 year had a significantly worse actuarial survival than those with stages 0 to 2 (p < 0.01). By 3 years after retransplantation, the forced expiratory volume in 1 second was significantly lower in patients who underwent reoperation because of obliterative bronchiolitis than in patients who underwent retransplantation because of acute graft failure or an airway complication (p = 0.02). Only 31% of patients who underwent retransplantation because of obliterative bronchiolitis were free of bronchiolitis obliterans syndrome at 3 years versus 83% of patients who underwent retransplantation because of other indications (p = 0.02). CONCLUSIONS: Preoperative ambulatory status predicts early survival and center volume predicts intermediate-term outcome after retransplantation. Improved management strategies are necessary to prevent the development of progressive graft dysfunction after retransplantation for obliterative bronchiolitis.

Actuarial Analysis↗

The influence of lung volume reduction surgery on ventilatory mechanics in patients suffering from severe chronic obstructive pulmonary disease.

Recently, lung volume reduction [LVR] removal of about 20% of lung volume), has been performed to treat severe emphysema. Little is known, however, about the mechanism and time course of functional improvement, and the reasons that such patients can be tracheally extubated very early. Therefore, we studied changes in ventilatory mechanics in 12 patients after LVR. Measurements of work of breathing (WOB), intrinsic positive end-expiratory pressure (PEEPi), dynamic compliance (Cdyn), and mean airway resistance (Rawm) were performed the day before surgery, early postoperatively, and 1 and 3 mo after surgery. All measurements were performed on tracheally extubated patients, simultaneously assessing esophageal pressure via esophageal balloon catheter and air flow via tightly adjusted mask. Standard spirometry was assessed pre-operatively and 1 and 3 mo postoperatively. The patients presented with forced expiratory volume in 1 s (FEV1), of 670 +/- 50 mL and pathological values of WOB and PEEPi. All patients were successfully tracheally extubated within 5 h postoperatively. Immediately thereafter, a marked and sustained decrease in WOB, PEEPi, and Rawm was noted, as well as an increase in Cdyn. Ventilatory mechanics improved immediately after LVR, probably due to decompression of lung tissue, thereby enabling successful tracheal extubation.

Adult↗

Lung retransplantation: institutional report on a series of twenty patients.

BACKGROUND AND METHODS: Between 1986 and 1995, 124 isolated lung and 29 combined heart-lung transplantations were performed at our institution. Twenty of these procedures were retransplantations. Four different types of reoperations were performed: ipsilateral single lung retransplantation (n = 3), single lung retransplantation after bilateral or heart-lung transplantation (n = 7), bilateral retransplantation after bilateral lung transplantation (n = 5), and bilateral retransplantation after single lung transplantation (n = 5). Nine patients underwent retransplantation while still in the intensive care unit after the primary transplantation. Indications for retransplantation in these patients were primary graft failure in seven and bronchial complications in two patients. In 11 patients a late retransplantation (3 to 30 months after the first transplantation) was performed. The indication was obliterative bronchiolitis in nine and late bronchial complications in two patients. Overall, 13 patients were ventilator-dependent before retransplantations. RESULTS: Overall survival was 52.8% and 36.2% at 1 and 12 months, respectively. For early retransplantation the survival rate at 1 month was only 22.2% with 2 patients alive 5 and 22 months after the retransplantation. For late retransplantation survival at 1 and 12 months was 70.7% and 50.5%, respectively (p = 0.07), and the longest surviving patient was at 47 months after retransplantation at the time this article was written. Patients who were ventilator-dependent before retransplantation had a significantly worse outcome (survival at 1 and 12 months: 33.8% and 25.4% versus 85.7% and 57.1% for all others, p = 0.055). Of those surviving to date, all were in New York Heart Association class I or II. CONCLUSIONS: We conclude that late and elective lung retransplantation achieves acceptable results when offered to patients with chronic pulmonary dysfunction but with otherwise stable conditions. In view of the poor results, early acute retransplantation should be performed much more restrictively.

Adolescent↗

Tailoring of the lung to overcome size disparities in lung transplantation.

BACKGROUND: Between October 1989 and December 1994 in 13 (four single and nine bilateral lung transplantations) of 124 lung transplantations, pulmonary allografts were considered to be too large to fit into the recipient thoracic cavity. METHODS: In all these patients (emphysema n = 6, fibrosis n = 4, pulmonary hypertension n = 3), the transplanted lungs were trimmed by extra anatomic wedge resections with the use of mechanical stapling devices to reach an acceptable size. RESULTS: No postoperative complication attributable to the tailoring procedure was observed. CONCLUSIONS: Tailoring of the lung is a safe and efficient method to overcome moderate size disparities between donor and recipient lungs.

Humans↗

Influence of human leukocyte antigen matching on long-term outcome after lung transplantation.

BACKGROUND AND METHODS: The importance of human leukocyte antigen matching for long-term outcome after lung transplantation is uncertain. We therefore analyzed retrospectively 78 consecutive primary, isolated lung transplantations (37 female, 41 male; 40 single, 38 bilateral) performed between October 1989 and October 1995 for which human leukocyte antigen typing of both donor and recipient was available. The follow-up ranged from 1 day to 60.3 months. Graft failure, defined as retransplantation or patient death, served as end point. RESULTS: Graft survival was significantly better with one mismatch at the B locus than with two mismatches (p = 0.046): 67% versus 51% and 61% versus 25% graft survival at 12 and 36 months, respectively. For the B and DR loci combined, a marked matching effect was also observed (p = 0.21 for zero to two mismatches versus three to four mismatches: 81% versus 62% and 51% versus 29% graft survival at 12 and 36 months, respectively. The sum of mismatches at the A, B, C, and DR loci combined showed a similar effect (p = 0.17 for zero to four mismatches versus five to eight mismatches: 83% versus 62% and 58% versus 29% graft survival at 12 and 36 months, respectively. Although no clear effect could be shown for the isolated DR locus, the outcome for the three patients with zero mismatches was notably good: one patient is alive at 27 months, two died 37 and 48 months after transplantation. The number of acute rejection episodes showed a clear but insignificant correlation to the number of mismatches. A similar trend was observed for the incidence of bronchiolitis obliterans syndrome. CONCLUSIONS: In summary, a strong influence of human leukocyte antigen matching on the long-term outcome after lung transplantation is suggested by our results. A clear trend toward improved graft survival with better human leukocyte antigen matching was observed, with the most significant effect occurring at the B locus.

Adolescent↗

[Lung volume reduction in emphysema--experience and results of the first 2 years].

Between September 1994 and August 1996 Lung Volume Reduction Surgery (LVRS) was performed through median sternotomy, videoendoscopically or by thoracotomy in 60 patients (age 33 to 80 years, mean 56.7 years). All these patients had severe emphysema despite maximal conservative and physical therapy. The areas with the most destroyed lung parenchyma were resected by means of linear stapling devices, 3 patients (20%) out of 15 who were operated via sternotomy died postoperatively due to aspiration pneumonia, multiorgan failure and acute hepatic failure. In the videoendoscopic group with 45 patients, 2 patients (4.4%) died due to multiorgan failure and cardiorespiratory failure. 72.7% of the remaining patients showed a significant functional improvement (postoperative FEV1 > 130% of the preoperative value) with a marked decrease of dyspnea. There was no significant improvement in 23.7% of the patients (postoperative FEV1 = 90 to 110% of the preoperative value) and 3.6% of the patients had a functional deterioration. Residual volume decreased from 317.0 +/- 12.4% of predicted (%p) preoperatively to 226.2 +/- 8.8 %p within the first month (p = 0.0001). FEV1 significantly increased from 23.7 +/- 1.3 %p preoperatively to 36.6 +/- 4.1 %p during the first 6 months postoperatively (p = 0.0016). Radiological signs of hyperinflation and distention of the thorax preoperatively improved to narrowed intercostal spaces and a more shaped diaphragm. These morphological changes resulted in better ventilatory muscle function. The intrinsic PEEP significantly decreased from 5.92 +/- 0.64 cm H2O preoperatively to 1.70 +/- 0.25 cm H2O postoperatively (p = 0.0001). The work of breathing decreased from 1.58 +/- 0.09 J/l preoperatively to 0.99 +/- 0.07 J/l postoperatively (p = 0.0001). In conclusion, LVRS is an excellent therapeutic option for patients with severe emphysema and additional signs of severe hyperinflation with significant postoperative functional improvement and marked increase in quality of life.

Female↗

[Surgical technique and results of bilateral volume reduction in patients with pulmonary emphysema].

Between 9/94 and 3/96 volume reduction was performed on 29 patients by a median sternotomy or videoendoscopic approach. Perioperative mortality occurred in three patients. The residual volume decreased within the first month from preoperative 308.8 +/- 13.4% of predicted (%p) to 217.9 +/- 12.7%p (p < 0.05). FeV1 significantly improved to 37.9 +/- 4.6%p after 3 months, versus 23.5 +/- 1.8%p preoperatively (p < 0.05). Intrinsic PEEP substantially decreased from 6.69 +/- 0.91 cm H2O preop to 0.93 +/- 0.28 cm H2O initially after surgery (p < 0.005). This was paralleled by the work of breathing: 1.78 +/- 0.2 J/l preoperatively versus 0.77 +/- 0.04 J/l postoperatively (p < 0.005). In conclusion, VR is a safe and successful option for patients with pulmonary emphysema, who show signs of marked hyperinflation.

Female↗

Anemia and erythropoietin levels in lung transplant recipients.

An evaluation of 26 surviving outpatient lung transplant recipients at one center showed that 65% (17/26) had significant anemia (hemoglobin < 11 g/L for women, < 14 g/dl for men) at a median follow-up of 13.5 months after transplantation (range, 1-41 months). There were 14 men and 12 women with a mean age of 45.1 years (range, 23.1-66.7 years). Fifteen had a double allograft and 11 had a single allograft. Anemia was normochromic and normocytic/macrocytic with a tendency to anisocytosis, with normal reticulocyte counts. Iron deficiency (transferrin saturation < 20%) was found in 35% (6/17) of anemic patients, and two of them also had ferritin levels < 15 micrograms/L. In addition, vitamin B12 was decreased in 1 patient. Folate levels were all normal. Erythropoietin levels were significantly decreased in anemic lung transplant recipients as compared with nontransplanted iron-deficient anemic patients (median, 1 mU/ml, range 1-41 mU/ml, vs. 53 mU/ml, 15-88 mU/ml; P < 0.05). In nonanemic lung transplant recipients, erythropoietin levels were decreased too, as compared with normal controls (median, 2 mU/ml, range 1-21 mU/ml, vs. 5 mU/ml, 3-32 mU/ml; P < 0.05). Investigation of peripheral stem cells in 9 patients showed normal stimulation of erythroids (burst-forming unit, erythroid; median, 573 cells/ml; range, 128-1898 cells/ml) independent of erythropoietin concentrations. Analysis of putative prognostic factors, such as age, surgical procedure (double vs. single lung allograft), indication for transplantation, time after transplantation, infection status, presence of bronchiolitis obliterans, immunosuppression (+/- azathioprine), serum creatinine, creatinine clearance, hypertension, and arterial partial pressure of oxygen, did not demonstrate any difference in erythropoietin concentrations. Only the sex variable revealed a trend to higher levels in women than in men (median, 4 mU/ml, range 1-41 mU/ml, vs. 1 mU/ml, 1-16 mU/ml; P > 0.05). The causes for low erythropoietin levels are not quite understood yet; however, they offer a rationale for the treatment of chronic anemia with recombinant human erythropoietin.

Adult↗

Evaluation of solitary pulmonary nodules with dynamic contrast-enhanced MR imaging--a promising technique.

The evaluation of a solitary pulmonary nodule (SPN) is one of the most frequently encountered challenges in thoracic radiology. In addition to a "state-of-the-art" evaluation of SPNs with CT and biopsy techniques, recently the assessment of the enhancement characteristics with iodinized contrast agents has shown its potential to improve the characterization of SPNs. We investigated whether dynamic contrast-enhanced MRI is suitable to assess the degree and kinetics of MR contrast enhancement and whether this technique could help in the noninvasive specification of SPNs. We studied prospectively 21 patients with SPNs. T1-weighted and proton density-weighted spoiled gradient-echo breath-hold images (2D-FLASH) were obtained before and after the administration of Gd-DTPA in a standard dosage of 0.1 mmol/kg body weight. The maximum enhancement and the initial velocity of contrast uptake were assessed and correlated with pathohistological findings. To quantify contrast enhancement, we used the relative signal intensity increase (S(rel)) and the recently introduced enhancement factor (EF) and contrast uptake equivalent (CE). Dynamic contrast-enhanced MRI proved to be well suited for the assessment of the contrast enhancement characteristics of SPNs. Significant differences were found in the degree and kinetics of contrast enhancement for specific types of nodules. Malignant neoplastic SPNs enhanced stronger and faster than benign neoplastic SPNs. The strongest and fastest enhancement, however, was found in a benign type of nodules where histology revealed inflammatory/fibrous lesions. These differences in contrast enhancement between the different pathohistological groups were more significant when EF and CE rather than S(rel) was used for the quantification of contrast enhancement. The results of this study indicate a potential role for dynamic contrast-enhanced MRI in the preoperative noninvasive evaluation of SPNs using EF and CE as contrast uptake assessment parameters.

Contrast Media↗

Recurrence of obliterative bronchiolitis and determinants of outcome in 139 pulmonary retransplant recipients.

An international series of pulmonary retransplantation was updated to identify the predictors of outcome and the prevalence and recurrence rate of obliterative bronchiolitis after operation. The study cohort included 139 patients who underwent retransplantation in 34 institutions in North America and Europe between 1985 and 1994. Eighty patients underwent retransplantation because of obliterative bronchiolitis, 34 because of acute graft failure, 13 because of intractable airway complications, 8 because of acute rejection, and 4 because of other indications. Survivors were followed up for a median of 630 days, with 48 patients alive at 1 year, 30 at 2 years, and 16 at 3 years after retransplantation. Actuarial survival was 65% +/- 4% at 1 month, 54% +/- 4% at 3 months, 45% +/- 4% at 1 year, 38% +/- 5% at 2 years, and 36% +/- 5% at 3 years; nonetheless, of 90-day postoperative survivors, 65% +/- 6% were alive 3 years after retransplantation. Life-table and univariate Cox analysis revealed that more recent year of retransplantation (p = 0.009), identical match of ABO blood group (p = 0.01), absence of a donor-recipient cytomegalovirus mismatch (p = 0.04), and being ambulatory immediately before retransplantation (p = 0.04) were associated with survival. By multivariate Cox analysis, being ambulatory before retransplantation was the most significant predictor of survival (p = 0.008), followed by reoperation in Europe (p = 0.044). Complete pulmonary function tests were done yearly in every survivor of retransplantation and bronchiolitis obliterans syndrome stages were assigned. Eleven percent of patients were in stage 3 at 1 year, 20% at 2 years, and 25% at 3 years after retransplantation. Values of forced expiratory volume in 1 second decreased from 1.89 +/- 0.13 L early after retransplantation to 1.80 +/- 0.15 L at 1 year and 1.54 +/- 0.16 L at 2 years (p = 0.006, year 2 versus baseline postoperative value). Most of this decrease occurred in patients who underwent retransplantation because of obliterative bronchiolitis, whereas the pulmonary function of patients who underwent retransplantation because of other conditions did not significantly change. We conclude that survival after pulmonary retransplantation is improving. Optimal results can be obtained in patients who are ambulatory before retransplantation. Compared with recent data after primary lung transplantation, bronchiolitis obliterans syndrome does not appear to recur in an accelerated manner after retransplantation. As long as early mortality as a result of infection can be minimized, pulmonary retransplantation appears to offer a reasonable option in highly selected patients.

ABO Blood-Group System↗

Tissue polypeptide specific antigen for the detection of lymphoproliferative diseases induced by cyclosporin.

AIM: To evaluate the efficacy of tissue polypeptide specific (TPS) antigen for the early detection of cyclosporin A (CyA) induced post-transplant lymphoproliferative diseases. METHODS: Serum concentrations of TPS antigen were analysed using a monoclonal enzyme immunoassay and whole blood CyA concentrations were measured using high pressure liquid chromatography. Infection with Epstein-Barr virus and cytomegalovirus was detected by determining levels of IgM and IgG antibodies directed against viral capsid antigen (VCA). Immunohistochemistry and analysis of clonality were carried out on formalin fixed, paraffin wax embedded tissue. RESULTS: The mean serum concentration of TPS antigen in the eight transplant recipients investigated was 60 U/l during periods without complication (control), 101 U/l during infection, 166 U/l when the diagnosis of a lymphoma was confirmed, and 172 U/l when lymphoma and infection coincided. Increased TPS antigen concentrations were detected in six patients one month before detection of malignancy. After reduction of immunosuppression and the start of tumour regression, TPS antigen concentrations decreased. TPS antigen concentrations increased in the one patient who experienced a recurrence. CONCLUSIONS: Continuous monitoring of TPS antigen concentrations leads to the early discovery of CyA induced lymphoproliferative disease.

Adult↗

The pulmonary nodule after lung transplantation. Cause and outcome.

In the immunocompromised patient, the pulmonary nodule remains a diagnostic and therapeutic challenge. We studied the incidence, cause, diagnosis, and therapy of pulmonary nodules after lung transplantation (LTx). Eight out of 64 patients (12.5%) developed pulmonary nodules after a median follow-up of 5.8 months (range, 1 to 10 months). The median age was 30.5 years (range, 21 to 62 years). Solitary pulmonary nodules (n = 2) disappeared spontaneously within 3 weeks and were suspected to be of infectious origin. The cause of multiple nodules (n = 6) was posttransplant lymphoproliferative disorder (PTLD [n = 3]), aspergillosis (n = 2), and abscesses caused by Pseudomonas aeruginosa and Staphylococcus aureus (n = 1). After an initial chest radiograph, CT with fine-needle biopsy was the most valuable diagnostic tool. In six patients, nodules resolved within 10 weeks (median, 8 weeks). Two patients, however, died of sepsis (P aeruginosa and S aureus and Aspergillus, respectively). The differential diagnosis of pulmonary nodules after LTx primarily comprises PTLD and infection (bacterial or fungal). To improve the outcome, early, aggressive treatment is mandatory; therefore, serial CT scans are strongly recommended to be part of the diagnostic armamentarium in LTx recipients.

Adult↗

Seventy-two pulmonary retransplantations for obliterative bronchiolitis: predictors of survival.

BACKGROUND: Obliterative bronchiolitis (OB) occurs in up to 40% of patients in the intermediate term after lung transplantation. In recent years an increasing number of recipients with end-stage OB have been treated with retransplantation. METHODS: Seventy-two patients with OB underwent retransplantation at 26 North American and European centers a median of 590 days after their first transplant operation. The predictors of survival were determined using life table and Cox proportional hazards methods, and the recurrence rate of OB was determined in survivors. RESULTS: The actuarial survival rate was 71% +/- 5% at 1 month, 43% +/- 6% at 1 year, and 35% +/- 6% at 2 years; nonetheless, of the 90-day postoperative survivors, 63% +/- 7% were alive 2 years after retransplantation. Institutional experience with more than three pulmonary retransplantations (p = 0.008), reoperation in Europe (p = 0.013), donor-recipient ABO blood group identity (p = 0.018), and more recent year of retransplantation (p = 0.03) were associated with survival. On multivariate analysis, reoperation after 1989 (p < 0.001), retransplantation performed in Europe (p = 0.017), and being ambulatory immediately before reoperation (p = 0.022) were found to be predictive of a positive outcome. Pulmonary function test analyses confirmed that the forced expiratory volume in 1 second decreased from postoperative baseline values by 11% +/- 9% at 1 year and 27% +/- 10% at 2 years (p = 0.02; year 2 versus baseline). Fourteen percent of patients were in stage 3 of the bronchiolitis obliterans syndrome at 1 year postoperatively, with 33% affected at 2 years. CONCLUSIONS: The results of pulmonary retransplantation for OB are improving. Current evidence indicates that OB does not recur in an accelerated manner after retransplantation, although pulmonary function does worsen again by 2 years. Pulmonary retransplantation is appropriate only in selected patients with OB who are ambulatory and are operated on at experienced centers.

Adolescent↗

[Chronic thromboembolic pulmonary hypertension and its treatment with pulmonary thrombendarterectomy].

Chronic recurrent pulmonary embolism can lead to extensive pulmonary hypertension by obstruction of the pulmonary vessels. Pulmonary thrombendarteriectomy is a new approach to normalizing the elevated pulmonary vascular resistance by removal of the adsorbed thrombi. Between 1992 and 1994 we have operated on 8 patients aged between 34 and 62 years. The first patient died due to extensive reperfusion edema, all others showed significant improvement in hemodynamic parameters (mean pulmonary artery pressure preop. 63 +/- 5 mmHg; postop. 30 +/- 9 mmHg; Cardiac Index preop. 2.0 +/- 0.2 l/min; postop. 3.5 +/- 0.5 l/min; pulmonary vascular resistance preop. 1169 +/- 75 dyn; postop. 228 +/- 55 dyn) and exercise performance (NYHA classification preop. III-IV, postop. I-II). Pulmonary thrombendarteriectomy represents an efficient method to normalize elevated pulmonary pressure and exercise performance of patients with far-advanced chronic thromboembolic pulmonary hypertension.

Adult↗

[Diagnostic and therapeutic video thoracoscopy: conversion rate and costs].

With the further development of new surgical techniques, that allow for the performance of a variety of standard diagnostic and therapeutic procedures in a less invasive fashion, it is instructive to look at the complications of these new techniques, in order to define their role for general thoracic surgery. 372 patients have been treated by means of video-assisted thoracic surgery (VATS) between 1/1992 and 12/1994. A total of 934 open thoracic procedures were performed in the same time frame, 399 out of them for the same chest disorders as treated by VATS alternatively. In 40 cases (10.7%) the endoscopic procedure had to be converted to an open thoracotomy. The main reasons for conversion were inability to locate or resect lesions due to a deep or central position (n = 13), requirement of further resection (n = 10), adhesions (n = 9), fibrinopurulent empyema (n = 5), bleeding (n = 2) and single-lung-ventilation failure (n = 1). The mean operation time was significantly shorter with VATS compared to open procedures, except for decortications. The mean hospital stay was 4.2 days in the endoscopic and 7.9 days in the thoracotomy group. Cost analysis for both techniques included expenses for disposable instruments, the operation room, anesthesia, and total hospital charges. Higher costs for instruments for VATS procedures were compensated by shorter chest drainage, less postoperative need for analgetics and a significantly shorter hospital stay.(ABSTRACT TRUNCATED AT 250 WORDS)

Cost-Benefit Analysis↗

The use of recombinant human erythropoietin in lung transplantation.

Recombinant human erythropoietin (r-HuEPO) was administered in 4 lung transplant recipients to treat chronic anemia beyond the immediate postoperative period. There were 2 males and 2 females with a mean age of 38 years (range 22-49). None of the patients had major infection or rejection problems, and no blood products were used. Because of different individual responses duration of therapy was 1 to 17 weeks (median 5) with a total dosage ranging from 8 to 36 x 10(3) IU (mean 21 x 10(3)). The median single dose was 58 IU/kg (range 36-100). Hemoglobin levels increased significantly from 9.1 +/- 0.2 to 12.7 +/- 0.3 g/dl (mean +/- SE; p < 0.01). There were no side effects. r-HuEPO is recommended in treatment of chronic anemia in lung transplant patients to save blood products and to exclude the potential risk of transfusion-transmitted viral infections.

Adult↗