Biomedical subjects

R E Fraser

Publications and source records attributed to R E Fraser.

10 recordsLinked to original sources

PubMed1995

Combined microneurosurgical and thoracoscopic removal of neurogenic dumbbell tumors.

The resection of posterior mediastinal dumbbell tumors has until now required laminectomy and some form of open access to the thoracic cavity. Over a 1-year period, a novel surgical approach combining posterior microneurosurgical and anterior video-assisted thoracoscopy techniques was used in 4 patients. In 3 patients, the tumor was removed successfully with minimal postoperative discomfort and rapid recovery. In the fourth patient, limited thoracotomy became necessary to control bleeding. This new approach, which combines modern-day neurosurgical and general thoracic surgical techniques, appears safe and could become the preferred method for removing most benign posterior mediastinal dumbbell tumors.

Adult↗

PubMed1994

Open tube thoracoscopy: does it have a role in modern thoracic surgery?

To determine the role of open tube thoracoscopy in the diagnosis and management of thoracic diseases, a retrospective review of 48 patients was conducted. A mediastinoscope was used for open tube thoracoscopy. Eleven patients underwent diagnostic thoracoscopy, and 4 patients had thoracoscopy for cancer staging. All 11 diagnostic procedures yielded a diagnosis, and thoracic malignancies were staged accurately in all patients. Thirty-three patients underwent therapeutic thoracoscopy. Twelve therapeutic thoracoscopies were done for pneumothorax, 9 for loculated parapneumonic effusion or empyema, 4 for malignant effusions, 2 for traumatic hemothorax, 2 for wedge resection of peripheral lung cancers, and 4 for other indications. All but 1 therapeutic procedure were successful. Three patients experienced complications specific to thoracoscopy (empyema 1, prolonged air leak 1, chest tube site leakage 1). There were 5 deaths, but none were related to thoracoscopy. Open tube thoracoscopy is very effective for evacuation of loculated pleural fluid, pus, or blood, and it appears to have advantages over video thoracoscopy in these settings. Although open tube thoracoscopy is satisfactory for other simple pleural procedures and wedge resections of lung are possible, video thoracoscopic techniques are now preferred for these indications.

Adolescent↗

PubMed1994

Cystic hydatid lung disease in northwest Canada.

OBJECTIVE: To determine the optimal treatment of sylvatic cystic hydatid lung disease. DESIGN: Retrospective case study. SETTING: Five Edmonton hospitals serving northern Alberta and parts of the Northwest Territories. PATIENTS: Fourteen patients with cystic (Echinococcus granulosus) hydatid lung disease. INTERVENTIONS: Cyst enucleation, wedge resection and pulmonary lobectomy. MAIN OUTCOME MEASURES: Eradication of pulmonary hydatid disease and complications of treatment. RESULTS: Mean patient age was 32 years. Eight patients were symptomatic. Liver cysts were present in three patients. One of the three patients managed by observation required surgery for an expanding cyst. Surgery (13 procedures in 12 patients) was successful in eradicating pulmonary hydatid disease: 8 cyst enucleations, 3 wedge resections and 2 lobectomies were done. There was only one major postoperative complication (pneumatocele requiring repeat surgery). Intraoperative cyst rupture occurred in five cases, but anaphylaxis or seeding did not result. There were no bronchopleural fistulae. CONCLUSIONS: Sylvatic cystic hydatid lung disease is more benign than pastoral hydatid disease. Patients with asymptomatic cysts should be managed by observation. Surgery, consisting of endocyst enucleation or wedge resection, is indicated for symptomatic, enlarging or infected cysts.

Adolescent↗

PubMed1992

Turnover of hyaluronan in the rabbit pleural space.

Hyaluronan influences lung fluid balance. The clearance of lung hyaluronan by way of the pulmonary lymphatics and the pleural space is increased when fluid flux into the interstitium is increased. The purpose of this study was to determine the rate at which hyaluronan is removed from the pleural space. We injected hyaluronan, labeled with tritium in the acetyl group, into the pleural space of six rabbits. The appearance of [3H]H2O in serum was measured over time to calculate the turnover rate of hyaluronan. We found that the half-lives ranged between 8 and 15 h and were positively related to the amount of hyaluronan injected. At the end of the experiment, the contralateral pleural space was irrigated to determine the amount of pleural space hyaluronan, which was 0.3 micrograms/kg body wt.

Animals↗

PubMed1989

The origin and fate of hyaluronan in amniotic fluid.

The mechanisms which regulate the steady-state concentration and molecular weight of hyaluronan in the amniotic fluid of sheep at different gestational ages have been investigated. An attempt to trace the origin of the polysaccharide has been made by analyses of various fetal fluids (amniotic fluid, allantoic fluid, tracheal fluid, urine, and serum). The fate has been studied by injection of radioactively labelled hyaluronan into the amniotic cavity and following the tracer in fetal tissues and fluids. The concentration of hyaluronan in amniotic fluid varies considerably but is in the order of 5 mg/l at mid-pregnancy and decreases to 1 mg/l in late pregnancy. The polysaccharide has a Mr-distribution with a weight-average in the order of 10(6) at 10 to 13 weeks of gestation which decreases to 10(5) closer to term. Calculations show that urine contributes 0.1 and 0.5 mg of low-molecular (Mr = 10(4) hyaluronan per day in mid- and late pregnancy, respectively, and the lung 10-20% of that amount in the form of high-molecular weight polymer (Mr greater than 10(6). The hyaluronan disappears from the amniotic cavity by bulk flow due to fetal swallowing. It is taken up and degraded in the fetal intestine. Molecules of Mr = 10(3) can pass the intestinal barrier. Calculations show that about 0.5 mg and 1.0 mg of hyaluronan is eliminated per day from the amniotic fluid at 12 and 17 weeks of gestation, respectively. Thus, the higher rate of elimination and the relatively high urinary contribution in more mature fetuses explain the low concentration and Mr of amniotic hyaluronan in late gestation, whereas a slower elimination combined with a relatively larger contribution of high molecular weight hyaluronan both from lung and urine and possibly from other sources are responsible for the higher concentration and Mr of the compound in early pregnancy.

Allantois↗

PubMed1970