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Biomedical subjects

L P Fielding

Publications and source records attributed to L P Fielding.

At least 73 records · Page 4Linked to original sources
PubMed1984

Local recurrence following 'curative' surgery for large bowel cancer: II. The rectum and rectosigmoid.

1988 patients with an adenocarcinoma of the rectum (1292; 65 per cent) or rectosigmoid (696; 35 per cent) have been studied. A resection (1700 patients) or polypectomy (124 patients) was performed in 1824 (92 per cent) and, of the former, 1376 patients either underwent abdominoperineal (AP) excision of the rectum (788 patients) or an anterior resection (598 patients). The in-hospital mortality was 63 patients (8 per cent) for AP and 44 (7 per cent) for anterior resection, and a curative resection had been performed in 504 (71 per cent) of those undergoing an AP, and 393 (71 per cent) of those undergoing an anterior resection. Follow-up information is available for 478 patients (95 per cent) who underwent an AP and 370 (94 per cent) who underwent an anterior resection. More patients have developed a local recurrence after an anterior resection (67; 18 per cent) than after AP (57; 12 per cent) (Logrank chi2 = 6.6, d.f. = 1, P less than 0.02) (stratified for sex and Dukes' stage). This difference is not accounted for by a lesser margin of distal clearance after an anterior resection; firstly because the margin of clearance was not different in those who did and those who did not develop a local recurrence (AP: whole group = 4.4 cm, local recurrence = 4.5 cm; anterior resection: whole group = 3.0 cm, local recurrence = 3.1 cm) and secondly because for each centimetre of distal clearance there was a consistently greater probability of recurrence for anterior resection (Logrank chi2 = 9.1, d.f. = 1, P less than 0.01) (stratified for sex, Dukes' stage and distal clearance margin).

Adenocarcinoma↗
PubMed1984

Large bowel cancer: surgical pathology and its relationship to survival.

Modifications of Dukes' (1932) classification of rectal tumours have led to confusion. From the data of 2518 patients who had undergone curative colorectal surgery the interrelationships between tumour penetration, grade, vascular invasion and pattern of lymph node involvement have been examined and their individual relevance to survival determined. Subdivision of Dukes' A cases into those confined to the muscularis mucosae (A) and those penetrating into, but not through, the bowel wall (B1) should be abandoned. Despite interrelationships between lymph node status, grade of tumour and vascular invasion, they all contribute prognostic information independent of each other. Apical lymph node involvement, more than four lymph nodes involved and extensive primary tumours with nodal involvement all carry a bad prognosis. Although interrelated each variable is individually relevant. However, subgroups of patients with Dukes' C tumours have an observed survival significantly better than expected. When few lymph nodes are involved or the primary tumour is confined to the bowel wall but lymph nodes are involved, the expectation of life is equivalent to Dukes' B.

Adenocarcinoma↗
PubMed1984

Covering stoma for elective anterior resection of the rectum: an outmoded operation?

A prospective multicenter study of the management of large bowel cancer recorded the results in 4,500 patients in whom 2,056 have had an elective colorectal anastomoses. Of these patients, 15.8 percent had a synchronous covering stoma to protect the anastomoses. Although the anastomotic leak rate was high in patients with a stoma, no overall differences were observed in mortality between those patients who had a covering stoma and those patients who did not (7 percent and 6.1 percent, respectively). However, when surgical policies were analyzed, clinically large and statistically significant differences were found. Some surgeons frequently used a covering stoma for low anterior resection whereas others only rarely did so. The differences in anastomotic leak and mortality were 20 percent and 7.8 percent, and 8.4 percent and 3.6 percent, respectively. We conclude that all surgeons should know their own clinical and radiologic anastomotic leak rate. If and when this figure becomes low (less than 5 percent), the covering stomas will become necessary except for the very rare and difficult case.

Adenocarcinoma↗
PubMed1982

Gastric acid secretion induced by impromidine in the dog and man: analysis of dose-response relationships.

The new histamine H2-receptor agonist, impromidine, was used to assess three models of dose-response curves in vivo. Vm and ED50 values were calculated for gastric acid output to infusions of impromidine in the dog with a Heidenhain pouch and in man. In two models Michaelis-Menten kinetics were assumed: the linear transformation using the Eadie-Hofstee plot and the non-linear hyperbola, but in the third method the logistic function allowed the data to be analysed without making assumptions about the steepness of the curves. In the dog all three models gave similar results both for calculated Vm and ED50. Curve steepness from the logistic function was found to be 0.98 +/- 0.023 - not different from that assumed for the hyperbola (where steepness = 1). The results in man were different: the Eadie-Hofstee plot did not produce a significantly linear fit while the logistic function produced the smallest standard errors. The logistic curve slope was almost twice that assumed for the hyperbola (1.8 : 1) and it seems, therefore, that impromidine-induced gastric acid secretion does not follow Michaelis-Menten kinetics in man and data should be analysed using methods which allow the calculation of curve steepness.

Animals↗
PubMed1981

Gastric mucosal blood flow and acid secretory changes in man with impromidine: a new specific histamine-H2-receptor agonist.

The effect of impromidine, a new histamine-H2-receptor agonist, on gastric mucosal blood flow (neutral red clearance) and acid secretion was studied in nine volunteers. Impromidine stimulated a dose-dependent increase in neutral red clearance and acid secretion. Simultaneous cimetidine in three doses caused a parallel shift to the right for both acid output and clearance with unchanged maxima compatible with simple surmountable antagonism. There were small cardiovascular changes: an increased heart rate with a decreased diastolic pressure during infusion of impromidine. These changes were antagonised by cimetidine.

Adult↗
PubMed1981

Histopathology reporting in large bowel cancer.

A review of histopathology reports on 2046 patients in the large bowel cancer project showed considerable observer variation in histological grading. Dukes staging, and lymph node harvest. These parameters have a well-established relationship to prognosis, but, if they are to be applied for both clinical and research purposes, they must be assessed consistently. A minimal level of information which should be recorded from a resection specimen is suggested, with a description of the methods by which this information can be obtained.

Adenocarcinoma↗
PubMed1980

Anastomotic integrity after operations for large-bowel cancer: a multicentre study.

Clinically evident anastomotic dehiscence was studied in 1466 patients who had undergone resection of a large-bowel adenocarcinoma. The overall incidence of anastomotic leakage was 13%, but the incidence varied between surgeons (range 0.5% to over 30%). Morbidity and mortality were significantly higher in those patients in whom the anastomosis failed to heal primarily. If these results are extrapolated to the national level, it should be possible by achieving results closer to those in patients without leakage to reduce overall post-operative mortality after resection of large-bowel cancer by 2% and to achieve an appreciable reduction in morbidity. Both factors are clinically important and, taken together, could result in appreciable saving of revenue.

Adenocarcinoma↗
PubMed1979

Large-bowel obstruction caused by cancer: a prospective study.

Patients with obstructing large-bowel cancer may be treated by primary tumour resection or the conventional staged tumour resection, and a prospective study comparing these two treatments was carried out. The post-operative outcome in 174 patients (of whom 90 underwent primary and 47 staged tumour resection) showed that the overall mortality was similar in both groups but that the duration of hospital stay in patients who underwent primary tumour resection was half that of those who underwent staged tumour resection. The mortality for primary tumour resection, however, was unexpectedly high for lesions proximal to the splenic flexure and unexpectedly low for lesions distal to this point. Of patients with distal tumours in whom a staged resection was planned, 35% died after a loop colostomy. The most striking result was that the ratio of postoperative death for trainee surgeons compared with fully trained surgeons was 3:1. It is concluded that patients with large-bowel cancer who present with intestinal obstruction should be treated by a fully trained surgeon and that immediate resection of the tumour should be considered for every patient.

Aged↗
PubMed1978

The effect of highly selective vagotomy on the relationship between gastric mucosal blood flow and acid secretion in man.

Previous work has shown that the duodenal ulcer population can be defined by a lower ratio between gastric mucosal blood flow and acid secretion (during pentagastrin stimulation) than is found in normal subjects. The results of the present investigation have shown that the ratio is restored to normality by highly selective vagotomy. This suggests that increased tonic activity of the vagus on the parietal cell is one of the important disorders in duodenal ulceration.

Adult↗