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Biomedical subjects

L P Fielding

Publications and source records attributed to L P Fielding.

At least 55 records · Page 3Linked to original sources
PubMed1989

Does vasoactive intestinal polypeptide mediate the pathophysiology of bowel obstruction?

We hypothesized that bioactive peptides might be released into the portal circulation and mediate pathophysiologic alterations accompanying small bowel obstruction. We studied this question in a subacute canine small bowel obstruction model using 50 percent diameter occlusion. Control animals underwent sham laparotomy. Vasoactive intestinal peptide (VIP), peptide YY, and gastrin were measured in portal and systemic plasma by specific radioimmunoassays at 24-hour intervals as the obstruction progressed to completion over 5 days. All peptides in both groups demonstrated portal and peripheral gradients. In control dogs, peptide concentrations did not change postoperatively but VIP increased markedly in obstructed dogs, demonstrating a median portal level of 95 pmol/liter at 96 hours compared with 31.5 pmol/liter in control animals. These portal VIP levels are known to cause hypersecretion and splanchnic vasodilation in experimental models. The release of vasoactive compounds such as VIP may mediate local pathophysiology in human small bowel obstruction. A similar explanation of the systemic effects is consistent with the known cardiopulmonary bioactivity of VIP.

Animals↗
PubMed1989

Low back injury in industry: the value of a recovery program.

Low back pain is the most frequent chronic disabling condition in the United States in patients younger than 45 years, and it is the second largest cause of employee absenteeism. In this retrospective study involving extreme working conditions at an industrial plant, we found that 20% of all employees incurred a back injury (occupational and nonoccupational) during the 12-month study period, costing more than 5,000 days of work lost, and approximately $920,000. Based on these findings a three-phased program of education/prevention, physical therapy, and an on-site rehabilitation workshop was implemented. After the first operational year, the net saving to the corporation was $255,000, and all employees who participated in the program returned to work within 60 days. We conclude that good job design, employee education on back injury prevention, and immediate on-site rehabilitation for injuries incurred can reduce employee disability and lost work time thus benefiting the employer and employee alike.

Absenteeism↗
PubMed1988

Clinical-pathologic staging of large-bowel cancer. A report of the ASCRS Committee.

After surgical treatment in patients with large-bowel cancer, a prediction about the likelihood for cure remains uncertain despite the availability of several different types of staging systems. A committee of the American Society of Colon and Rectal Surgeons has reviewed the available data and concludes that future assessments of prognosis should be based on a combination of clinical and pathologic prognostic factors, using multivariate statistical techniques for the analysis. Although many important prognostic factors are known, there is much to learn about these and other items before a confident prediction of long-term outcome can be made. An extension of these methods should be possible to assist in prospective clinical decision-making based on clinical and investigational data. Such a system would be of particular value for patients with rectal cancer for whom cost-benefit relationships of alternative treatments can be so controversial. It is concluded that an accepted, standard nomenclature is required to reach both these objectives using large multicenter studies.

Colonic Neoplasms↗
PubMed1988

Surgeon-related variability in the outcome of cancer surgery.

Statistical and clinical differences between reports of surgical therapy are usually ascribed to differences in the named method of treatment. However, it is becoming increasingly clear that surgeons vary in the ability to produce a given result; this phenomenon is sometimes referred to as "surgeon-related variability." Thus surgical treatment should be seen as the resultant vector of the named procedure plus the effect of such surgeon-related variability. These propositions have significance for the conduct of prospective randomized controlled trials which set out to test the efficacy of alternative surgical treatments. These issues are of particular importance in the cancer field because therapy is becoming more commonly multiphasic and includes both medical and surgical treatments.

General Surgery↗
PubMed1987

Drunk drivers and medical and social injury.

Alcohol-related traffic injuries are a major cause of death, pain, and suffering and a major contributor to health care costs in the United States. We reviewed the medical and legal consequences of 252 motor vehicle accidents involving drivers admitted to St. Mary's Hospital between 1981 and 1985, with particular attention to patients with a blood alcohol concentration equal to or above the legally defined threshold for intoxication (100 mg per deciliter). There were 84 such patients, with a median blood alcohol level of 218.5 mg per deciliter. Few of these patients were referred either to alcoholism-rehabilitation programs or to the courts for prosecution. We conclude that both drunk drivers and the population at large are poorly served by current medical and legal practices. Because denial of reality and prevarication are hallmarks of alcoholism, we make two recommendations. First, in order to encourage physicians to refer all injured patients with high blood alcohol concentrations to detoxification and rehabilitation programs, injury to intoxicated drivers should be made a reportable condition. Second, prosecution for driving under the influence of alcohol should be made easier by simplifying the procedures for providing the courts with blood alcohol measurements obtained as part of normal clinical care. Physicians must act in the interest of their patients. The two recommended changes in current practice would help provide a firm framework within which physicians could advise patients about appropriate treatment for alcoholism. If such steps are not taken or are ineffective, vigorous legal action should be encouraged, because society has the right to demand that innocent people not be endangered by intoxicated people who drive motor vehicles.

Accidents, Traffic↗
PubMed1987

Continent ileostomy simplified by musculo-serosal window. An experimental study.

Experience with pouch procedures in the quest for continence after total panproctocolectomy has been associated with significant reoperation rates, making these procedures suitable only for highly selected and motivated patients. The purpose of this study was to determine, in an acute dog model, the optimum configuration of a new continence mechanism consisting of a musculo-serosal window formed between the afferent and efferent loops of small bowel. The following geometric measures were varied: single or double window (efferent and afferent loops, respectively); percent circumference of bowel wall used for the window; and distance between pouch apex and window. Intraluminal pressure against volume infused in standard time was recorded. Four hundred seventy experiments in 47 pouches were conducted. The authors suggest that the optimal configuration for this "valve" is bowel circumference used for the window--50 to 60 percent on both the afferent and efferent loops, with a pouch-valve distance of 5 to 6 cm. It is concluded that a biologic valve obviating the need for a nipple may be possible. The geometric configuration has been defined and should be studied in a chronic animal model to determine long-term results.

Animals↗
PubMed1987

Local tumor recurrence after curative resection for rectal cancer. A ten-hospital review.

Local tumor recurrence rates after curative rectal cancer surgery with the end-to-end anastomosis stapler (EEA) are reportedly high. Therefore, a retrospective review in ten Yale-affiliated hospitals was undertaken to establish the outcome of surgical resection for rectal cancer in this patient population. Of those 373 patients who had had curative resections, 192 (52 percent) were abdominoperineal resections (APR); 105 patients (28 percent) had restorative resections with sutured anastomoses, and the EEA stapler was used in 76 patients (20 percent). There was an equal distribution of tumors in the various Dukes' stages in all three procedures. Local tumor recurrence was: APR 19 percent, SUT 17 percent, and EEA 24 percent, but local tumor recurrence was more frequent after EEA than APR for tumors 7 to 10 cm from the anal verge (32 vs. 13 percent, respectively, P less than 0.05), and the time to recurrence was least in EEA patients. It is concluded that local tumor recurrence is higher than expected for all three procedures and that the EEA stapler was associated with a greater risk of local tumor recurrence. These findings are attributed to surgeon-related technical operative factors rather than to the nature of the tumors themselves.

Adult↗
PubMed1986

Prediction of outcome after curative resection for large bowel cancer.

Prospectively collected information on 2524 patients who had undergone "curative" resection for colorectal cancer was analysed to establish the rank-order of importance of both clinical and pathological factors affecting outcome. The patients were divided into two groups. In the first, a statistical weighting was established for each prognostic factor and those that influenced long-term survival were, in order of importance, lymph node status, tumour mobility, number of lymph nodes positive for tumour, presence of bowel obstruction, and depth of primary tumour penetration. Factors that influenced in-hospital mortality were cardiopulmonary complications, intraabdominal sepsis (without anastomotic leak), presence of bowel obstruction, and age. In the second group these mathematical weightings were applied, and the predicted and observed outcomes were in close agreement. Statistical techniques of this kind will be of value in prognosis and in analysis of the results of new treatment regimens.

Adult↗
PubMed1986

Influence of tumour site on presentation, management and subsequent outcome in large bowel cancer.

To demonstrate any difference in outcome between patients with carcinoma at various sites within the large bowel, analysis of a large number of patients is necessary. From the Large Bowel Cancer Project, 4292 patients have been evaluated to compare mode of presentation, surgical management, pathological findings and outcome. Carcinoma at the splenic flexure was associated with the highest risk of obstruction (49 per cent); postoperative cardiopulmonary complications (36 per cent); in-hospital mortality (18 per cent); and the lowest age-adjusted 5-year survival (28 per cent), even after curative resection (38 per cent). This survival disadvantage was seen even in those without obstruction. Further, it was not accounted for by differences in age, sex, Dukes' stage or tumour differentiation between the various sites as stratification by these variables failed to alter significance (log rank chi 2 = 11.1; d.f. = 4; P less than 0.05). Compared with carcinoma of the left colon and rectum, tumours in the right colon were more likely to be poorly differentiated and locally advanced (in terms of fixation and penetration of the bowel wall) but were not associated with a higher risk of either distant spread at presentation or local recurrence. Age-adjusted 5-year survival following curative surgery was higher for the right colon (65 per cent) than the left (59 per cent).

Adult↗
PubMed1985

Regional blood flow and water content of the obstructed small intestine.

The effects of small-bowel obstruction on the regional distribution of blood flow and water content were studied in a new chronic dog model. Nonstrangulative obstruction was induced 40 cm proximal to the canine ileocolic valve. Blood flow was measured with 15-micron microspheres and hemodynamic and respiratory values were recorded before (experimental phase I) and five days after (experimental phase II) the induction of the obstruction. Two separate control groups of dogs were studied: baseline controls and sham-operative groups (phases I and II). Hemodynamic and respiratory values were stable in both phases in all groups. A comparison of sham phase-II data with the experimental phase-II data in the 120-cm segment of bowel proximal to the site of obstruction showed an 85% increase in blood flow (range, 49% to 106%); for the 280 cm of bowel proximal to the site of obstruction, there was a 6% increase in water content (range, 5% to 9%), and a 39% decrease in dry bowel weight (range, 34% to 46%). These findings help illustrate the pathophysiologic characteristics of microvascular changes in bowel obstruction, which are likely to have particular clinical significance for patients with cardiopulmonary diseases.

Animals↗
PubMed1985

Malignant large bowel obstruction.

Of 4583 patients in the Large Bowel Cancer Project, 713 (16 per cent) were obstructed. The site of greatest risk was the splenic flexure (49 per cent). Advanced stage was neither the full reason why some patients obstructed nor for their subsequent poor prospects (age-adjusted 5-year survival: not obstructed, 45 per cent; obstructed, 25 per cent). Also, there was no greater risk of vascular invasion, no heavier lymph node burden and no worse tumour differentiation in patients with obstruction. In-hospital mortality was high (23 per cent), was not reduced by either a policy of primary or staged resection and was not influenced by the site of obstruction. There was no survival advantage for either policy, but hospital stay after primary resection was half that of staged. Immediate anastomosis in the obstructed left colon had a high clinical leak rate (18 per cent versus 6 per cent elective; P less than 0.001). Both registrars and consultants had similar mortality rates for elective primary resection and for the management of obstruction itself (as evidenced by results after the first stage of a staged resection). Selection probably accounts for the very much better results achieved by consultants for primary resection in the presence of obstruction (in-hospital mortality: consultants, 13 per cent; registrars, 24 per cent).

Adenocarcinoma↗
PubMed1985

Risks of surgery for upper gastrointestinal hemorrhage: 1972 versus 1982.

A retrospective comparison was undertaken to determine if the risks of undergoing surgery for nonvariceal upper gastrointestinal hemorrhage had changed between 1972 and 1982. In 1982, patients were on the average 9 years older, there was a significant decrease in bleeding from duodenal ulcers compared with 1972 data, gastric ulcer rates remained unchanged, and diffuse gastritis occurred more frequently in 1982. Mortality and morbidity rates showed no significant differences; however, the patient population did change with the emergence of older patients, in whom bleeding developed after hospitalization for other reasons. These patients comprised 30 percent of the 1982 study population. If further improvements in surgical treatment of upper gastrointestinal hemorrhage are to occur, these patients must be identified and aggressively managed.

Adult↗
PubMed1984

Local recurrence following 'curative' surgery for large bowel cancer: I. The overall picture.

The Large Bowel Cancer Project is a collaborative prospective study of 4228 patients with a histologically proven adenocarcinoma, of whom 2336 (55 per cent) survived a 'curative' resection. Follow-up information is available on 2220 patients (95 per cent). Subsequently, 309 (14 per cent) have developed a local recurrence confirmed by: biopsy (127; 41 per cent), clinical examination (77; 25 per cent), X-ray (15; 5 per cent), a raised CEA (2; 1 per cent), or some other method - e.g. CT scan or a confident unbiopsied laparotomy finding (88; 29 per cent). Statistically significant factors (chi2 test, P less than 0.05) associated with local recurrence are: Dukes' classification: A 4 per cent; B 13 per cent; C 18 per cent Tumour differentiation: Well 11 per cent; Moderate 14 per cent; Poor 21 per cent Obstruction: Absent 13 per cent; Present 21 per cent Perforation: Absent 13 per cent; Present 28 per cent Tumour mobility: Freely mobile 11 per cent; Others 21 per cent Operation performed (rectal and rectosigmoid tumours): Abdomino-perineal 12 per cent; Anterior resection 18 per cent; Surgeon (Consultant only): Range less than 5 per cent to greater than 20 per cent. Stratification of the above variables altered only the statistical significance pertaining to tumour differentiation (P less than 0.1, d.f. = 2). In particular, the differences between Consultant surgeons remained.

Adenocarcinoma↗