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C T Bolliger

Publications and source records attributed to C T Bolliger.

At least 55 records · Page 3Linked to original sources
PubMed1999

Stents in the management of malignant airway obstruction.

Surgical resection is feasible in only 20% of patients with lung cancer: less than 30% of these patients survive > 5 yrs and almost 95% of them require palliative treatment. During the course of disease, 30% of lung cancers cause obstruction of the trachea and main bronchi with subsequent respiratory distress, bleeding and infection. Similar problems arise through secondary pulmonary malignancies. There are several types of central airway obstruction; this influences the modality used for their treatment. The three basic types of stenosis are endoluminal, extraluminal and a combination of both. A mainly endoluminal stenosis can be treated with various resection techniques, such as laser, electrocautery or cryotherapy; for an extraluminal compression the only option is placement of stents, which results in efficient palliation and may prolong survival. Various stent models have been developed for the treatment of inoperable airway stenoses. They consist mainly of two types: metal and silicone devices, or combinations of both (hybrid models). The choice of a specific stent depends on the nature of the airway obstruction, the endoscopist's preference and the overall costs of the procedure. The best treatment results are usually obtained using a combination of stent placement followed by tumour-specific treatment such as irradiation or chemotherapy.

Airway Obstruction↗
PubMed1999

[Prosthesis: indications, contraindications and follow-up].

The use of stents or endoprostheses to treat tracheobronchial obstruction is firmly established. The most important indication for stent placement are inoperable stenoses of the central airways, whose main component is extrinsic compression due to malignant, less frequently to benign disease. In experienced hands the short- and long-term results are excellent. When considering stent placement the functional benefit for the patient should be highly likely. With respect to this, the parameters to be assessed before and in regular intervals after stent placement include a physical examination, a chest roentgenogram or a CT scan, pulmonary function tests, bronchoscopy, and quality of life. Of all the various stents on the market the cylindrical silicone stent designed by Dumon is the one most widely used and represents the standard against which all other models have to compete. Expandable metal stents have advantages over most silicone stents through their thin walls and their excellent adaptability to greatly varying airway diameters. The current development of covered expandable stents should make it possible to combine the good biocompatibility known of silicone stents with the excellent flexibility and favorable wall to inner diameter ratio of the metal stents. This development will make expandable stents much more versatile for the treatment of malignant and benign obstructions of the central airways. Effective sealing of fistulas in airways without a concomitant obstructive component is another most welcome indication for this type of stents. The future might well belong to hybrid stents with metallic components and a smooth synthetic covering of silicone or polyurethane. The ongoing research in stents shows that the "ideal stent" for all purposes does not exist and probably never will. Quite often the specific stent type needed can only be determined during therapeutic endoscopy. Every specialist practicing in the area of stenting should therefore have an armamentarium of a few different types available and use the one best indicated in a specific situation.

Airway Obstruction↗
PubMed1998

A phase I study of adenovirus-mediated wild-type p53 gene transfer in patients with advanced non-small cell lung cancer.

Mutations of the tumor suppressor gene p53 are the most common genetic alterations observed in human cancer. Loss of wild-type p53 function impairs cell cycle arrest as well as repair mechanisms involved in response to DNA damage. Further, apoptotic pathways as induced by radio- or chemotherapy are also abrogated. Gene transfer of wild-type p53 was shown to reverse these deficiencies and to induce apoptosis in vitro and in preclinical in vivo tumor models. A phase I dose escalation study of a single intratumoral injection of a replication-defective adenoviral expression vector encoding wild-type p53 was carried out in patients with incurable non-small cell lung cancer. All patients enrolled had p53 protein overexpression as a marker of mutant p53 status in pretreatment tumor biopsies. Treatment was performed either by bronchoscopic intratumoral injection or by CT-guided percutaneous intratumoral injection of the vector solution. Fifteen patients were enrolled in two centers, and were treated at four different dose levels ranging from 10(7) to 10(10) PFU (7.5 x 10(9) to 7.5 x 10(12) particles). No clinically significant toxicity was observed. Successful transfer of wild-type p53 was achieved only with higher vector doses. Vector-specific wild-type p53 RNA sequences could be demonstrated in posttreatment biopsies of six patients. Transient local disease control by a single intratumoral injection of the vector solution was observed in four of those six successfully transduced patients. There was no evidence of clinical responses at untreated tumor sites. Wild-type p53 gene therapy by intratumoral injection of a replication-defective adenoviral expression vector is safe, feasible, and biologically effective in patients with advanced non-small cell lung cancer.

Adenoviridae↗
PubMed1998

[Tobacco abuse: background and countermeasures].

The extreme extent of world-wide tobacco consumption, mainly in the form of cigarette smoking, is a phenomenon of the 20th century and can be termed a pandemic. Partly due to the massive and uninhibited advertising of the tobacco companies smoking prevalence has dramatically increased until the mid-sixties. Since then thousands of reports on the damaging-effects of smoking have been published which has led to a change in attitude and to a decrease in smoking prevalence at least in industrialised countries. In Switzerland about 25% of the adult population smoke, but the percentage in the age group between 25 to 34 years is significantly higher. Smoking is the most important preventable cause of disease; this has been underlined by recent findings that about 50% of smokers will eventually die from their habit. Regular smokers-usually defined as regularly smoking more than 10-15 cigarettes daily-are nicotine dependent and do not smoke because they want to, but because they have to. Although 60-70% of smokers would like to quit, they fail without help. Nevertheless, smoking cessation is possible: the most important issue is the smoker's own motivation. Psychological counselling and nicotine replacement therapy (NRT) given as either patch, chewing gum, or nasal spray are merely aids to enhance success. With intensive counselling and NRT a maximum success rate of about 30% can be expected assessed 1 year after quit date. In general the use of NRT doubles the success rate of any chosen form of intervention. Cessation of smoking in young people is currently considered the best form of prevention.

Adolescent↗
PubMed1998

Functional evaluation of the lung resection candidate.

Advances in operative technique and perioperative care have considerably reduced surgical morbidity and mortality after pulmonary resections. Various single and combined parameters of functional operability have been proposed to assess the surgical risk. Pulmonary function tests adequately assess the pulmonary risk, and baseline or stress electrocardiography, echocardiography and nuclear cardiac studies assess the cardiac risk. Patients with normal or only slightly impaired pulmonary function (forced expiratory volume in one second (FEV1) and transfer factor of the lung for carbon monoxide (TL,CO) > or = 80% of predicted) and no cardiovascular risk factors can undergo pulmonary resections up to a pneumonectomy without further investigation. For others, exercise testing, pulmonary split-function studies, or a combination of these two methods are recommended. Exercise testing, most frequently performed as a symptom-limited test with the measurement of maximal oxygen uptake (V'O2,max), assesses both the pulmonary and cardiovascular reserves. A V'O2,max of <10 mL.kg(-1).min(-1) is generally considered prohibitive for any resection, a value of >20 mL.kg(-1).min(-1) or >75% of predicted normal, safe for major resections. Split-function studies are radionuclide-based estimations of the predicted postoperative (ppo) values of various parameters. The currently used ppo-parameters are FEV1-ppo, TL,CO-ppo and, most recently, V'O2,max-ppo. Suggested cut-off values for safe resection are: for FEV1-ppo and TL,CO-ppo > or = 40% pred; and for V'O2,max > or = 35% pred, combined with an absolute value of > or = 10 mL.kg(-1).min(-1). The lowest acceptable ppo-values will still have to be established by additional prospective studies. In the long-term, resections involving not more than one lobe usually lead to an early functional deficit followed by later recovery. The permanent functional loss in pulmonary function is small (< or = 10%) and exercise capacity is only slightly reduced or not at all. Pneumonectomy, on the other hand, leads to an early permanent loss of about 33% in pulmonary function and 20% in exercise capacity. Thus, pulmonary function tests alone overestimate the functional loss after lung resection.

Exercise Test↗
PubMed1997

Treatment of early parapneumonic empyema by "medical" thoracoscopy.

We report on a consecutive series of 16 patients with complicated parapneumonic effusion or empyema, in whom, after a failed attempt at tube drainage, thoracoscopy under local anesthesia ("medical" thoracoscopy) was performed for debridement and placement of a chest tube. This approach led to immediate clinical improvement in all patients and to definitive cure in 12 of 16. In 4 patients open surgical debridement was necessary after a few days in an elective procedure. In a subgroup of thoracoscopically treated patients, lung function tests were performed at least 6 months after the procedure and did not demonstrate significant restrictive changes. We conclude that thoracoscopy under local anesthesia is a valuable addition to the treatment options in patients with multiloculated, complicated parapneumonic effusion or empyema not responsive to simple tube thoracotomy. The procedure is less taxing for the patient and less expensive than video-assisted thoracoscopic surgery under general anesthesia or open decortication.

Adult↗
PubMed1997

[Sudden dyspnea].

Dyspnea is abnormal respiration experienced as unpleasant, concomitant with excessive respiratory labor. This review limits differential diagnoses of dyspnea to common pulmonary causes in which dyspnea often assumes a "sudden" character. Restrictive diseases of lung parenchyma are therefore not covered. The following disease states are illustrated with respect to history, clinical presentation and emergency treatment: hyperventilation-syndrome, pulmonary embolism, pneumothorax, central airway-stenosis, asthma and chronic obstructive pulmonary disease. In the case of asthma the conception of "home management" and telemedicine are presented.

Acute Disease↗
PubMed1997

[Endoscopic contamination with Mycobacterium tuberculosis].

A 60-year-old woman who had been investigated and treated unsuccessfully for chronic cough was referred for a bronchoscopy. The cultures of bronchial aspirates were positive for Mycobacterium tuberculosis. The radiological and endobronchial findings were typical of chronic bronchitis, but in the light of the positive cultures endobronchial tuberculosis was diagnosed and the patient was started on a standard 3-drug regimen. She developed a classical hypersensitivity reaction to isoniazid. Later the diagnosis had to be revised when molecular typing demonstrated contamination.

Antitubercular Agents↗
PubMed1997

Conservative management of a broncho-oesophageal fistula in a patient with non-Hodgkin's lymphoma.

We describe the case of a 56-year-old male patient with a 2-year history of productive cough and weight loss. The diagnosis of a broncho-oesophageal fistula due to a low-grade Non-Hodgkin's lymphoma was made. The patient was referred for surgical closure of the fistula and resection of the left lower lobe because of intractable severe pneumonia. As an alternative treatment option, oesophageal or bronchial stent placement was considered. Because of the relatively favourable prognosis of this type of lymphoma, treatment with chemotherapy alone and a feeding gastrostomy were started. After eight cycles of cyclophosphamide and prednisone, the fistula healed spontaneously. Two years later, the patient continues to do well and is in remission. In patients with Non-Hodgkin's lymphoma and an oesophagorespiratory fistula, treatment should first be conservative; surgery or stent placement should be postponed.

Antineoplastic Agents↗
PubMed1996

An Airway Wallstent for the treatment of tracheobronchial malignancies.

BACKGROUND: The palliative effect of a new Airway Wallstent with a polyurethane covering was tested in patients with inoperable malignant lesions of the central airways. METHODS: Thirty six stents were inserted in 27 patients with obstruction (n = 24) or fistulae (n = 3), 15 of whom later received radiotherapy. The degree of symptom relief was assessed 1, 30, and 90 days after stent insertion. RESULTS: Stent deployment was successful in all patients. Significant improvements were observed one day after placement compared with before placement, with no change at 30 and 90 days, in dyspnoea index (mean (SD) 3.2 (0.7) before stent insertion compared with 1.8 (0.7) one day after insertion); Karnofsky index (32 (18) before insertion compared with 55 (15) one day after insertion); and obstruction of airway diameter (85 (11)% before insertion compared with 10 (12)% on day 1 after stent insertion). Stent-related complications needing later interventions included retained secretions (five patients), granuloma formation at ends of the stent (four patients), and stent migration (four patients). Over a median observation period of two months (range two days to 8.5 months) all stent coverings remained intact without delamination or tumour ingrowth. CONCLUSIONS: The Airway Wallstent provided excellent palliation for malignant obstructions and fistulae of the central airways. Retention of secretions and granuloma formation at the ends of the stent warrant minor technical improvements.

Adult↗
PubMed1996

Pulmonary function and exercise capacity after lung resection.

The influence of pulmonary resection on functional capacity can be assessed in different ways. The aim of this study was to compare the effect of lobectomy and pneumonectomy on pulmonary function tests (PFT), exercise capacity and perception of symptoms. Sixty eight patients underwent functional assessment with PFT and exercise testing before (Preop), and 3 and 6 months after lung resection. In 50 (36 males and 14 females; mean age 61 yrs) a lobectomy was performed and in 18 (13 males and 5 females; mean age 59 yrs) a pneumonectomy was performed. Three months after lobectomy, forced vital capacity (FVC), forced expiratory volume in one second (FEV1), total lung capacity (TLC), transfer factor of the lungs for carbon monoxide (TL,CO) and maximal oxygen uptake (V'O2,max) were significantly lower than Preop values, increasing significantly from 3 to 6 months after resection. Three months after pneumonectomy, all parameters were significantly lower than Preop values and significantly lower than postlobectomy values and did not recover from 3 to 6 months after resection. At 6 months after resection significant deficits persisted in comparison with Preop: for FVC 7% and 36%, FEV1 9% and 34%, TLC 10% and 33% for lobectomy and pneumonectomy, respectively; and V'O2,max 20% after pneumonectomy only. Exercise was limited by leg muscle fatigue in 53% of all patients at Preop. This was not altered by lobectomy, but there was a switch to dyspnoea as the limiting factor after pneumonectomy (61% of patients at 3 months and 50% at 6 months after resection). Furthermore, pneumonectomy compared to lobectomy led to a significantly smaller breathing reserve (mean +/- SD) (28 +/- 13 vs 37 +/- 16% at 3 months; and 24 +/- 11% vs 33 +/- 12% at 6 months post resection) and lower arterial oxygen tension at peak exercise 10.1 +/- 1.5 vs 11.5 +/- 1.6 kPa (76 +/- 11 vs 86 +/- 12 mmHg) at 3 months; 10.1 +/- 1.3 vs 11.3 +/- 1.6 kPa (76 +/- 10 vs 85 +/- 12 mmHg) at 6 months postresection. We conclude that measurements of conventional pulmonary function tests alone overestimate the decrease in functional capacity after lung resection. Exercise capacity after lobectomy is unchanged, whereas pneumonectomy leads to a 20% decrease, probably due to the reduced area of gas exchange.

Adult↗
PubMed1996

The use of the covered Wallstent for the palliative treatment of inoperable tracheobronchial cancers. A prospective, multicenter study.

STUDY OBJECTIVE: To investigate the safety, efficacy, and tolerance of the covered Wallstent for the palliative treatment of inoperable tracheobronchial cancer. DESIGN: An 8-month prospective study employing either a rigid bronchoscope or a flexible delivery system for prosthesis insertion. SETTING: Multicentric setting involving four teaching hospitals in Switzerland and Germany. PATIENTS: Forty patients (29 men, 11 women), average age of 62 years, presenting with an inoperable tracheobronchial cancer. INTERVENTIONS: After partial airway recanalization with an Nd-YAG laser, the covered Wallstent was inserted 23 times using a rigid bronchoscope (Rigidstep device), and 27 times using a flexible delivery system (Telestep device) under fluoroscopic and endoscopic visualization. RESULTS: Clinical and endoscopic examination at 1, 30, and 90 days showed improvement in the bronchial lumen and in the dyspnea index. No serious complication (death, perforation, hemorrhage, inability to remove an improperly placed prosthesis) was observed during surgery. Late complications included migration (12%), inflammatory granulations or tumor regrowth at the tip of the prosthesis (36%), and symptomatic retention of secretion (38%). CONCLUSIONS: Compared with other tracheobronchial prostheses, notably the Dumon stent, the covered Wallstent presents the following advantages: insertion with visual guidance, treatment of extrinsic compressions and esophagobronchial fistulas, and little chance of migration when the prosthesis diameter is chosen correctly. The following disadvantages can be noted: high price; both repositioning and extraction of the released stent are more difficult, though certainly possible; and risk of granulations at the tips of the prosthesis and retention of secretions. Suggestions are made for potential improvements to the stent and insertion system that may result in a significant decrease in early and late complications.

Adult↗