Biomedical subjects

W S Egerton

Publications and source records attributed to W S Egerton.

15 recordsLinked to original sources

PubMed1997

Relative dispersion of intravascular transit times during isolated human limb perfusions for recurrent melanoma.

AIMS: We have characterized the relative dispersion of vascular and extravascular markers in the limbs of three patients undergoing isolated limb perfusions with the cytotoxic melphalan for recurrent malignant melanoma both before and after melphalan dosing. METHODS: A bolus of injectate containing [51Cr] labelled red blood cells, [14C]-sucrose and [3H]-water was injected into an iliac or femoral artery and outflow samples collected at 1 s intervals by a fraction collector. The radioactivity due to each isotype was analysed by either gamma [51Cr] or beta [14C and 3H] counting. The moments of the outflow fraction-time profiles were estimated by a nonparametric (numerical integration) method and a parametric model (sum of two inverse Gaussian functions). RESULTS: The availability, mean transit time and normalised variance (CV2) obtained for labelled red blood cells, sucrose and water were similar before and after melphalan dosing and with the two methods of calculation but varied between the patients. CONCLUSIONS: The vascular space is not well-stirred but characterized by a CV2 similar that reported previously for in situ rat hind limb and rat liver perfusions. A flow-limited blood-tissue exchange was observed for the permeating indicators. Administration of melphalan did not influence the distribution characteristics of the indicators.

Aged↗

PubMed1988

Two cases of pseudo-aneurysm of the gastroduodenal artery.

Pseudo-aneurysm of the gastroduodenal artery is a rare cause of bleeding-complicated pancreatitis. The use of computerized tomography and angiography lead to early diagnosis. The key to surgical treatment is arterial inflow occlusion prior to opening the aneurysm.

Adult↗

PubMed1988

The Martin Titanline arterial clamp. A new lightweight alternative.

When haemostatic clamps are applied, evidence of injury at the site of clamp application may be seen when the clamp is removed. Rarely, the intima may be disrupted. When a new arterial clamp became available, a study was designed to compare the Martin Titanline arterial clamp (13-143-35, curved arterial clamp) with several other arterial clamps already in use. The Martin clamp is a modified pivot-point, preset-tension, spring-controlled arterial clamp. The closing pressures of several clamps were measured objectively. The injury produced when the clamps were applied to occlude the blood flow on the carotid artery of a dog was assessed by histological study of the excised segments of the arterial wall. Histological cross-sections were prepared from canine carotid artery which had been perfused for 1 h after the clamp had been applied for 1 h. Histological evidence of injury was limited to disruption of the intimal layer and compression of the medial layer. No significant difference between the amount of damage caused by the DeBakey, Satinsky or Martin clamp was identified. When compared to the other varieties of clamp listed above, the Martin clamp had a significantly lower closing pressure (304 g) compared with 580g (Bulldog), 580 g (Satinsky), and 686 g (DeBakey). The Martin clamp was easier to apply, did not obstruct the operative field as readily and had good clamp-retention characteristics throughout the procedure.

Arteries↗

PubMed1984

Portal vein perfusion of the isolated rat liver: some markers of hyperthermic liver damage.

The cytotoxic effects of hyperthermia on tumours are readily measured. Parameters of injury to normal tissues are needed to evaluate therapeutic potential. Fifty-five isolated rat livers were perfused in vitro for 180 min in order to determine parameters of hyperthermic injury. During this period they were heated for 1 h at temperatures ranging from 37 degrees to 45 degrees and then assessed for evidence of hyperthermic injury. The most critical indicator of hyperthermic injury was sustained depression of bile production. Bile secretion decreased by 80% after heating at temperatures above 42 degrees. Aspartate amino transferase (AST) release increased significantly at temperatures of 42 degrees and above. Potassium and variable amounts of glucose were released into the medium during heating, reflecting temporary changes in metabolism at high temperatures.

Animals↗

PubMed1977

An electron microscopic study of the mode of donor cell death in unmodified rejection of pig liver allografts.

The only type of cell death found in pig liver allografts 1 week after technically successful operation was apoptosis. Its extent paralleled the degree of mononuclear cell infiltration of the liver parenchyma, and mononuclear cells were found applied to the surfaces of hepatocytes showing early stages of the process. The results suggest that cellular immune attack induces apoptosis of donor cells, and that the action is a direct one. However, implication of other factors such as vascular damage in the induction of apoptosis in the grafts could not be excluded.

Animals↗

PubMed1976

An improved M.B., B.S., "final" examination in surgery.

A new final year examination in surgery has been devised. It consists of a clinical assessment made by a surgical tutor over a period of six weeks throughout a student's surgical term, a visual, clinically orientated written examination a "spotter-type" practical examination and a viva-voce examination. Correlation with students' previous performances has been good and the examination appears to have solved many of the problems which necessitated its development.

Australia↗

PubMed1976

Experimental coronary occlusion in calves: the effect of hyperglycaemia on ventricular fibrillation threshold.

Measurements of ventricular fibrillation threshold (VFT) were made in two groups of bovine calves, each weighing 25 to 30 kg, before and after ligation of the anterior descending branch of the coronary artery. In the control group, the VFT was determined before occlusion of the anterior descending coronary artery, and the observations were repeated at 20-minute intervals after occlusion. A 33% reduction in VFT was observed 20 minutes after the occlusion. Prior loading with glucose by infusion of 100 ml of 10% glucose prevented the significant fall in VFT.

Animals↗

PubMed1975

Early jaundice after pig liver transplantation.

Of a series of pigs surviving orthotopic liver allotransplantation with end-to-end anastomosis of the bile duct, 70% were noted to be jaundiced at the end of the first week after transplantation. Seven animals in a subsequent series were investigated biochemically, but operative cholangiography, and by liver biopsy seven days after transplantation, when the jaundice was maximal. There was definite cholangiographic obstruction in only one animal, and this finding was subsequently confirmed at autopsy. This was also the only animal in which bile culture was positive. Jaundiced animals appeared to have more marked histological evidence of rejection than non-jaundiced ones. The jaundice was probably a result of transient rejection and usually resolved spontaneously without immunosuppression.

Animals↗

PubMed1974