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Biomedical subjects

J B Davis

Publications and source records attributed to J B Davis.

At least 91 records · Page 5Linked to original sources
PubMed1988

Childhood farm injury: the role of the physician in prevention.

Farm-related trauma occurs in more than 25,000 children per year with almost 300 patients dying from these preventable injuries. The incidence of associated farm-machinery injuries and fatalities is increasing at an alarming rate with the majority occurring in young boys during the summer months. Between 1979-1985, 234 patients with traumatic injuries were admitted to our Pediatric Surgery Service. Seven of these, six boys and one girl, age ranges from 2-15 years were treated for severe farm-related injuries. Modified injury severity score was calculated with an average score of 31.5 (range 9-66). Four patients sustained or required amputation of a major extremity(ies) as a result of the injury. Two patients had multiple long bone fractures with associated neurologic or abdominal injury. One patient exsanguinated from massive liver lacerations. Five of the six surviving patients are disabled to varying degrees because of their injuries. This report provides support for the establishment of federal safety standards for farm-related equipment. Guidelines for prevention are outlined. We believe that the child physician is obliged to encourage education programs in farming communities on safety measures and further should endorse the application for farms.

Accidents, Home↗
PubMed1987

Benthic invertebrates as indicators of urban and motorway discharges.

Spatial differences in the structure and composition of the invertebrate community of a suburban river (demonstrated by the use of indices) could be explained largely in terms of organic inputs but such indices were not suitable for the detection of the low level metal contamination associated with road runoff. Analysis of plant and animal tissue proved to be a more useful strategy and significant variation in metal concentrations in several organisms could be related to the chemistry of the river water and to road and urban discharges.

Animals↗
PubMed1987

Primary repair of esophageal atresia: how long a gap?

Primary esophagoesophagostomy is the treatment of choice for repair of esophageal atresia, particularly the more common type C atresia. Debate continues, however, regarding repair of the type A, or long-gap esophageal atresia. Since the pioneering work of Livaditis, Howard and Myers, the frequency of primary repair of long-gap atresia has increased. Interposition grafting, however, remains as the treatment for gaps longer than 6 cm or with absence of a distal intrathoracic esophageal segment. We report a case of primary esophagoesophagostomy with proximal esophagomyotomy in a 1,900-g infant with an absent distal intrathoracic esophageal segment and an eight vertebral body gap. Utilizing daily bougienage of the proximal and eventually the distal segment, a 1-cm gap was present at 6 months of age. With intraoperative fluoroscopy, the distal intra-abdominal esophageal segment was manipulated thru the esophageal hiatus. Thru an extrapleural approach with a proximal esophagomyotomy, a delayed primary anastomosis was successfully performed. She is currently 3 years old and has a normal barium swallow without stricture or gastroesophageal reflux.

Dilatation↗
PubMed1986

Hemodialysis access: elevated basilic vein arteriovenous fistula.

Vascular access in the pediatric patient with endstage renal disease (ESRD) can be a surgical challenge to perform as well as maintain. We have recently developed a new technique of elevating the basilic vein in the upper arm for the arteriovenous (AV) fistula instead of using a polytetrafluoroethylene (PTFE) graft. During the past 2 years, 66 patients with ESRD and unsuitable superficial veins have had basilic vein elevation. Of these 66 patients, four have been in children, aged 11 to 19 years. The technique of mobilization of the vein from the elbow to the axilla was similar to that described by Dagher et al except that we used one long incision. The new feature of this technique is that the vein is not rerouted laterally through a subdermal tunnel. Instead, after the AV fistula to the side of the brachial artery is created, the vein is elevated within the incision by closing the subcutaneous fascia beneath, and the skin over, the vein. Most veins could be used in 2 to 4 weeks. Of the entire group, the patency rate has been 55 of 66 (83.3%), with no infections or long-term morbidity. Of the four pediatric patients, there have been no thromboses or infections. We believe the operation to be easier to perform than the standard PTFE bridge graft. The subsequent AV fistula is easy to access, less likely to cause a "steal syndrome," less likely to become infected, and if it does become infected, more likely to respond to treatment with antibiotics.

Adolescent↗
PubMed1986

Current concepts in clinical therapeutics: intra-abdominal infections.

The etiology, pathophysiology, clinical presentation, and treatment of the two major types of intra-abdominal infections--peritonitis and abscesses--are described. Peritonitis of infectious origin is the acute response of the peritoneum to microorganisms; it is classified as primary (when the source of bacteria is not apparent) or secondary (usually involving perforation of a hollow structure of the GI tract with subsequent release of microbes). Peritonitis results in mortality because of fluid shifts and endotoxins that may cause hypovolemia and shock. Abscesses, purulent collections of fluid physically separated from the surrounding tissues, are the result of chronic inflammation following failure of the body to eradicate a pathogen completely. Secondary intra-abdominal infections are often polymicrobial because of the diversity of organisms in the GI tract. The size of bacterial inocula and the number and types of species present substantially affect patient outcome. The patient with peritonitis usually presents in acute distress, with generalized abdominal pain and faint bowel sounds. The presentation of the patient with intra-abdominal abscess is more variable and less dramatic; pain and fever may be present. The treatment of these infections requires the coordinated use of prompt surgical intervention, support of vital functions, and appropriate antimicrobial therapy. Surgical procedures are used to stop continuing bacterial contamination of the peritoneum, remove foreign material from the abdomen, and drain purulent collections; it is the foundation of treating most types of intra-abdominal infections. Aggressive fluid therapy is required to assure adequate intravascular volumes in most patients. Generally, antimicrobial coverage for both aerobes and anaerobes must be started before culture results are available. Antimicrobial therapy for specific types of infections is given in the article. Surgical procedures are the foundation of treatment of most intra-abdominal infections; antimicrobial agents active against aerobic gram-negative bacilli and anaerobes are important adjuncts.

Abdomen↗
PubMed1985

Supravalvular aortic stenosis. Clinical and pathologic observations in six patients.

Supravalvular aortic stenosis with a mean pressure gradient of 101 mm Hg was encountered in six patients aged 1 1/2 to 12 years. Three patients had Williams syndrome. In two other patients the stenosis was familial. The angiographic/anatomic subtype of deformity was hourglass in four patients, diffuse in one, and membranous in one. Four patients are alive following successful surgical repair; the other two died without surgery. Microscopically, disorganized medial elements with fibrotic intima sometimes containing lacunae were observed in five cases; the one other had valvelike tissue only. Ultrastructurally, thick irregular elastic fibers, abundant swirling collagen, hypertrophied smooth-muscle cells, and scant ground substance characterized the medial tissue defect. Although hemodynamics during intrauterine development may predispose to localization of the stenosis to the supra-aortic valvar region, the cause for the mural dysplasia remains uncertain.

Adult↗
PubMed1984

Mucinous cystic neoplasm of the pancreas with latent malignancy.

Mucinous cystic neoplasms of the pancreas are rare. They have traditionally been classified as cystadenoma or cystadenocarcinoma. Over a 5-year period, and three operations, a patient initially diagnosed as having a cystadenoma of the pancreas was subsequently found at the time of definitive total pancreatectomy to have a cystadenocarcinoma. The recent literature suggests that there is not distinction between cystadenoma and cystadenocarcinoma, since these tumors have been shown to contain coexisting areas of malignant and benign epithelium in both types. The authors' experience with this patient demonstrates the necessity for thorough histologic sectioning of these tumors to document the presence of carcinoma, since all of these tumors should be regarded as potentially malignant neoplasms. Surgical therapy for these lesions should be total excision whenever feasible.

Cystadenocarcinoma↗
PubMed1981

Atopy and wheeze in children according to parental atopy and family size.

The relationship between atopy and wheeze was examined in children, together with the possible influence on these conditions of parental atopy and family size. Children with a repeated history of wheezing were selected from an urban general practice population. The children, their first degree relatives, and a control group were examined for atopic status, atopy being defined as more than one positive immediate skin prick test response. The prevalence of wheeze in boys was 15.5%, in girls 7.6%, and of atopy in boys 19.7% and in girls 8.1%. Of 110 atopic children 70% had no atopic parent, 27% had one atopic parent, and in 3% both parents were atopic. The presence of parental atopy was associated with an increased prevalence of wheeze in boys but not in girls, 12.0% of boys having a history of wheezing if neither parent was atopic and 27.5% if either or both parents were atopic (p less than 0.05). The presence of parental atopy was associated with an increased prevalence of atopy in girls but not in boys, 6.1% of girls having atopy if neither parent was atopic and 18.9% if either or both parents were atopic (p less than 0.01). There was a strong association between atopy and wheeze for both sexes and no statistically significant difference in the prevalence of atopy or wheeze in children whether they were from two, three, or four child families.

Adolescent↗
PubMed1980

Patient compliance with antihypertensive medication.

Self-reported medication taking compliance behavior of 132 high blood pressure patients was analyzed using an expanded version of the health belief model. Subjects were selected through random sampling procedures from regular hypertension program sessions at a large urban hospital. A questionnaire was constructed to measure the model components, and interviews were conducted with each patient. Bivariate analysis showed that control over health matters, dependence on providers, perceived barriers, duration of treatment, and others' nonconfirming experience were significantly related to compliance (p < .05). Log-linear multivariate analysis revealed that three of these five variables--control over health matters, perceived barriers, and duration of treatment--contributed independently to patient compliance. Self-reported medication taking was significantly related to blood pressure control (p < .02). These data provide the basis for developing interventions for providers to facilitate the medication taking behavior of clinic patients.

Analysis of Variance↗
PubMed1978

Performance characteristics of a gamma camera over a wide range of energies.

The problem of choosing which collimator to use for imaging a new isotope has been approached by collecting resolution and sensitivity data for a selected group of isotopes. These have been chosen to be readily available and to have generally a single gamma-ray only. Resolution and sensitivity plots for a low energy collimator and a high energy collimator are presented and their use with several isotopes of interest is discussed. The interpretation of recommedations in the literature on the choice of collimators for newly introduced isotopes would be considerably simpler if data in this format were commonly available.

Humans↗