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Biomedical subjects

H Toomes

Publications and source records attributed to H Toomes.

At least 37 records · Page 2Linked to original sources

The ex-vivo isolated, perfused human lung model: description and potential applications.

An ex-vivo isolated, perfused, and ventilated human lung (IPHL) model is well suited for many kinds of physiological, pharmacological, and surgical studies, when the physiological and biochemical conditions in the lung can be maintained near to those in vivo. The aim of this work was to develop such a model. The lung preparations used were available after resection because of bronchial carcinoma. Since the tumor remains intact in these anatomical preparations, this model is particularly suitable for investigation of the pharmacokinetics and effects of anticancer agents. Carrying out a series of 52 IPHL experiments (with 11 whole-lung preparations and 41 lobe preparations), we have established an IPHL model which allows extracorporeal perfusion and ventilation of the resected lungs in physiological conditions for 2-3 hours. The net weight gain during the experiment, wet-to-dry weight ratio for lung tissue, angiography of the pulmonary artery, pulmonary vascular resistance, color and fluorescence of the lung surface, and alveolar gas diffusion into the perfusate proved to be useful parameters to assess the stability of the preparations and the quality of the experiments. To confirm that an intraparenchymal tumor was perfused via the pulmonary artery, methods to detect avidin and dextran-biotin in tumor tissue after administration into the perfusion solution were employed. Histological examination of bronchial as well as tumor tissue, a computerized histoanalyzation, and a tumor grading program demonstrated that IPHL experiments did not interfere with the grading and staging of the tumors-an important ethical precondition for the use of human preparations in an extracorporeal perfusion model.

Carcinoma, Bronchogenic↗

Video-assisted thoracoscopic pleurodesis. A survey conducted by the German Society for Thoracic Surgery.

As video-assisted thoracoscopic surgery has been performed for more than five years an inquiry was made to register and if possible to evaluate different pleurodesis procedures in the treatment of pneumothorax in Germany. 19 institutions provided information about 1365 operations. Overall there were 88 recurrences (6.5%). 26 (1.9%) severe bleeding complications or hemothorax and 39 (2.9%) persisting air leaks required further interventions. There were two (0.1%) hospital deaths. Recurrence rates showed a significant (p < 0.001) correlation to the type of pleurodesis used. Talcum pleurodesis had no recurrences and fibrin glue pleurodesis had the highest rate of recurrence (16.4%) both procedures being less frequent. After causal treatment, i.e. resection without any pleurodesis, recurrence rate is inconsistent and was 10.2% overall. Pleural abrasion was followed by a recurrence rate of 7.9% and pleurectomy of 4.4%. Both procedures induced significantly (p = 0.01) more bleeding complications (about 3%) than other procedures (0.4%). Promising was coagulation of the pleura parietalis with a recurrence rate of only 2.7% and a low rate of complications.

Data Collection↗

[Radical lung surgery interventions with special reference to lymphadenectomy].

Intraoperative lymph node staging plays an essential part in the surgical treatment of lung cancer. The mean number of resected lymph nodes in 237 patients was 17, with a minimum of 1 and a maximum of 60. The largest number was found in N1 regions as expected. The number of resected nodes in the paratracheal, tracheobronchial and subcarinal region was 4, in the paraoesophageal and ligament region 1.2. Twenty-two percent of the whole group showed an N2 situation. In 45% of the patients with N2 invasion, we found a lymph node skipping and in 25% only one positive N2 node. Thus, it is obvious that without a systematic lymph node dissection an exact staging is not possible.

Carcinoma, Bronchogenic↗

[Thoracic surgery in advanced age].

From 1990 through 1992, 70 patients 70 years of age or older (mean 72.8 years) underwent surgery for lung cancer at our hospital (47 males/23 females). 68 patients took part in a follow-up. Operative treatment consisted of standard lung resections in 42 cases. 17 patients underwent enlarged resections. In the postoperative period, complications occurred in 32 cases (47%). The overall operative mortality rate of 13% was mainly due to concomitant cardiovascular diseases and enlarged lung resections. Critical preoperative evaluation of the patients' functional status and selection of the proper operative procedure promise a successful treatment of lung cancer in the elderly.

Aged↗

[Minimally invasive surgery of large bullous pulmonary emphysema].

An enormous pulmonary cyst (phi approx. 20 cm) in a 72-year-old male patient with large bullous pulmonary emphysema caused compression of the right lung and the mediastinum with consecutive, O2-dependent dyspnoea at rest. The symptoms did not improve under conservative therapy of an accompanying COPD. Thus, in spite of two heart attacks in the previous history, an operation with bullectomy was indicated. A thoracotomy had to be avoided because of the very high cardiac risk. In the present case, a minimally invasive procedure enabled the complete cyst resection with a smooth postoperative course and an excellent functional therapeutic result.

Aged↗

The significance of prognostic factors for the resection of pulmonary metastases of breast cancer.

Breast cancer is the most common malignant disease in women in Europe. In 15-25% of cases, the isolated formation of pulmonary metastases occurs. To date these metastases have been treated mainly by chemotherapy, radiotherapy, or hormone therapy. However, good results through pulmonary metastatic resection have been reported increasingly in recent times. From 1979 to 1992, 103 breast-cancer patients underwent surgery for suspected pulmonary metastases in our clinic. Intraoperatively in 88% of the whole group the metastases were confirmed, but in the other 12% they proved to be benign tumors or primary bronchial carcinomas. The operative therapy is standardized in our clinic. The approach is via a median or transverse sternotomy. Wedge resection is the normal procedure, undertaken in 55% of the cases. Complications, which were completely reversible in all cases, occurred in 3%. The 30-day mortality rate was 0%. In the whole patient population, the actuarial 5-year survival was 27%; it was 31% among the completely resected women, whereas no patient undergoing incomplete resection survived 5 years. Taking prognostic criteria into account, there are clear trends. When the disease-free interval exceeded 2 years, the actuarial 5-year survival was 33%, and if the receptor status of the primary tumor was positive, the 3-year survival was 61% compared to 38% for cases with negative receptor status. If a solitary metastasis was removed, the actuarial 5-year survival was 35% as opposed to 0% in cases with more than five metastases.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Ultrastructural studies of acute rejection following single lung transplantation in the rat--histological and immunohistological findings.

Nowadays the acute and especially chronic lung rejection are the major problems after lung transplantation (L-Tx) with relevant influence on longterm survival. We performed lung transplantation in rats to study a possible role of ultrastructural lesions in the graft during the acute rejection process, concerning their reversibility/irreversibility and influence of the chronic rejection. Based on histologic and immunohistologic studies after L-Tx in MHC-different and strong reactive rat strain combination AVN-LEW and filial generation (AVN-LEW)F1-LEW (n = 57 and n = 32) electronmicroscopic studies (TEM, SEM) were performed in the combination AVN-LW (n = 20) on postoperative day 0, 1, 2 and 5, all without immunsuppressive therapy. Syngenic grafts (LEW-LEW; n = 12) served as controls. Histologically the allografts were classed according to the proven acute rejection phases latent, vascular, alveolar and destructive. The immunhistological and electronmicroscopic results correlated with these rejection phases. There was no difference between the rat strain combinations. All allografts developed acute rejection on postoperative day 2 and were destroyed on postoperative day 5/6. Initially T-helper-cells, later cytotoxic-T-cells and macrophages played the predominent role in the acute rejection process. In the ultrastructural specimens alterations of the blood vessels, pneumocytes type-II, and surfactant gave more information. Initially flattening of endothelial cells and circumscribed lesions of graft vessels occur, increasing in the allografts up to extensive vascular wall destructions, accompanied by total thrombotic occlusion. Disturbances of surfactant production observed in the grafts of all strain combinations are not homogenous.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

[Techniques in thoracoscopic surgery].

The presently known methods of thoracoscopic surgery are a symbiosis of traditional thoracic surgery and of new endoscopic techniques. The traditional methods determine the proceeding on the organ, the innovative ones the measure to reach it. The challenge is to carry out traditional procedures on the lung by means of the new technique without loss of quality. The accomplishments of simple thoracoscopic operations on lung, pleura, and mediastinum are mostly determined. In cases of major thoracic surgical interventions new resection techniques, not yet proven on lung vessels and bronchi are increasingly undertaken. This means an innovation in two respects and is therefore difficult to evaluate. In our clinic thoracoscopic surgical techniques are orientated towards preserving the established methods on the organ via new accesses with recently developed endoscopic instruments. After having treated over 400 patients, we are now able to show that the presented thoracoscopic methods offer an advanced and safe way towards modern thoracic surgery. However, it is too early to present standardized surgical techniques of thoracoscopic surgery.

Humans↗

[The status of surgical thoracoscopy in thoracic surgery].

Video-assisted thoracoscopic surgery is viewed as a sparing and safe alternative to thoracotomy for a wide spectrum of benign thoracic diseases. However the loss of palpation as well as the insufficiency of complete mediastinal lymphadenectomy are responsible for the uncertainty of the new method concerning curative oncological therapy. During the last two years we could replace thoracotomy by operative thoracoscopy in nearly all cases of recurrent pneumothorax and recurring pleural effusion. In a series of 447 endoscopic operations in 350 patients following distinct indications and strong prerequisites in terms of operating team and infrastructure of our department we could establish a high standard for this new operating method. The good postoperative results of this large series of thoracoscopic operations indicate the high rank of this new technique in thoracic surgery. Recurrence rates of 1.5% for pneumothorax surgery and 0 for pleurectomy for malignant pleural effusion can be compared to those in open thoracic surgery. Six weeks after the operation the postoperative lung function was normal in 80% of an initial group of patients.

Humans↗

Prerequisites, indications, and techniques of video-assisted thoracoscopic surgery.

During the last two years video-assisted operative thoracoscopy has introduced new impetus into thoracic surgery. Today it is viewed as a sparing and safe alternative to thoracotomy for a wide spectrum of indications. The prerequisites, instruments, and operative techniques are discussed. In oncological thoracic surgery it still remains to be verified whether the criteria of radicality are fulfilled by this new technique. Using video-assisted operative thoracoscopy, we have successfully operated on 209 patients with the following indications: recurrent pneumothorax (n = 94), interstitial lung disease (n = 25), coin lesion (n = 20), pleural effusion (n = 17), hyperhidrosis (n = 14), mediastinal tumor or lymphoma (n = 10), thoracic empyema (n = 9), bullous emphysema (n = 8), pleural tumor (n = 5), hematothorax (n = 3), malignant pericardial effusion (n = 3), and chylothorax (n = 1). The advantages of this minimally traumatizing operating technique lie in a better view of the operative site, the objectively measurable reduction in postoperative restriction, less pain, earlier postoperative mobilization, and shorter hospital stay. This operating technique, in addition to being sparing, requires markedly less time than a thoracotomy. The disadvantages are the two-dimensional monitor picture and, especially, the loss of palpation.

Anesthesia, General↗

Palmar thermometry for intraoperative success control of thoracic sympathectomy.

In a pilot study involving six patients, palmar thermometry was used as a non-invasive method for intraoperative success control during thoracic sympathectomy. Using commercially available thermo-elements and amplifier modules, a marked increase in temperature could be registered in five patients after the severance of their rami communicants grisei for the hand. This effect was associated with the long-term success of therapy for hyperhidrosis in all five patients. This initial experience demonstrates that palmar thermometry is sensitive enough to measure surgical success intraoperatively. The limit of the thoracic sympathectomy in the cranial direction is indicated intraoperatively and Horner's syndrome is avoided with certainty.

Body Temperature↗

Selective video-assisted thoracoscopic sympathectomy.

Video-assisted and thermometrically controlled thoracoscopic sympathectomy demonstrates new ways in the treatment of upper-limb hyperhidrosis. An anatomical portrayal of the sympathetic chain is possible as a result of the improved visualization and magnification of the operative area provided by the video-optic technique. The difference in temperature, registered by means of a thermometric sensor in the palm of the hand, indicates that the sympathetic nerves responsible for the hyperhidrotic segments have been severed. The number of postoperative Horner's syndromes will be reduced significantly with this method. Until now, we have successfully treated six thermometrically controlled patients. No recurrences have arisen during an 18 months observation period. Neither intraoperative nor postoperative complications were recorded. One patient complained of increased compensatory sweating of the trunk. Thermometrically controlled thoracoscopic sympathectomy is expected to improve the various forms of treatment available for sympathetic reflex dystrophies in the future.

Body Temperature↗

Single- and multiple dose pharmacokinetics of lonidamine in patients suffering from non-small-cell lung cancer.

Pharmacokinetic studies of lonidamine (1-[2,4-dichlorobenzyl]- 1H- indazole- 3-carboxylic acid, Doridamina: CAS 50264-69-2) in humans showed a wide variation of the plasma concentration-time profiles following a single peroral dose of 300 mg (Cmax between 6.5 and 40.9 micrograms/ml, tmax between 0.75 and 5.5 h). In order to investigate single and multiple dose pharmacokinetics after peroral administration of this chemotherapeutic compound, a study was performed involving 12 patients with non-small-cell malignancies of the lungs. Plasma and urinary concentration profiles were analyzed for determination of the pharmacokinetic parameters for lonidamine after single dose administration and in the steady state. In addition, age dependency and the presence of liver induction or inhibition was evaluated. Results indicate that steady state was reached after 2 dosing intervals of 12 h and no changes in liver metabolism or age dependent pharmacokinetics could be revealed after 4 days of multiple dose treatment.

Adult↗

[Conservative surgical techniques in the area of lung surgery].

An important condition for careful operations in lung surgery are modern anesthesia procedures like one-lung ventilation and high-frequency jet ventilation. The aim of careful procedures is the preservation of normal lung tissue. Most commonly broncho- and angioplastic resections are performed to avoid a pneumonectomy without loss of radicality. Minimally invasive endoscopic surgical techniques combined with laser application complete the spectrum of careful procedures in thoracic surgery, e.g., for resection of lung cysts or for thoracic sympathectomy.

Humans↗

[Lung changes caused by Mycobacterium xenopi infection in a patient with bone marrow transplantation: problems in differential diagnosis].

Pulmonary affections caused by atypical mycobacteria are an increasingly common problem particularly in patients with immune deficiency disorders. We here report a case of pulmonary infiltrates due to Mycobacterium xenopi in a patient after allogeneic bone marrow transplantation for acute myeloid leukemia in first complete remission and under immunosuppressive treatment with prednisolone and Cyclosporin A. While sputum cultures, serology as well as bronchial lavage and transbronchial biopsy remained inconclusive, diagnosis could only be established by open lung biopsy. We suggest that particularly in immunocompromised patients unclear pulmonary infiltrates require rapid and possibly invasive diagnostic procedures.

Adult↗

Lung volumes following resection of pulmonary metastases in paediatric patients--a retrospective study.

Pulmonary function was evaluated before and after 15 operations for resection of pulmonary metastases from osteogenic sarcoma. In the whole study group (ten patients, aged 13-18 years) preoperative vital capacity (VC) ranged from 62% to 122% (mean 83%) of predicted normal values for height. The operations were performed via median sternotomy. One-28 metastases were removed per session. Six months after the operations VC averaged nearly 95% of the preoperative values. Signs of bronchial obstruction or persistent pulmonary hyperinflation were only present in one patient with repeated operations. We conclude that resection of pulmonary metastases with limited loss of parenchyma leads to an almost complete recovery of preoperative pulmonary function parameters.

Adolescent↗