PubMed Health⌕ Search

Biomedical subjects

R Dempsey

Publications and source records attributed to R Dempsey.

At least 19 recordsLinked to original sources
PubMed1999

UCMP and the Internet help hospital libraries share resources.

The Medical Library Center of New York (MLCNY), a medical library consortium founded in 1959, has specialized in supporting resource sharing and fostering technological advances. In 1961, MLCNY developed and continues to maintain the Union Catalog of Medical Periodicals (UCMP), a resource tool including detailed data about the collections of more than 720 medical library participants. UCMP was one of the first library tools to capitalize on the benefits of computer technology and, from the beginning, invited hospital libraries to play a substantial role in its development. UCMP, beginning with products in print and later in microfiche, helped to create a new resource sharing environment. Today, UCMP continues to capitalize on new technology by providing access via the Internet and an Oracle-based search system providing subscribers with the benefits of: a database that contains serial holdings information on an issue specific level, a database that can be updated in real time, a system that provides multi-type searching and allows users to define how the results will be sorted, and an ordering function that can more precisely target libraries that have a specific issue of a medical journal. Current development of a Web-based system will ensure that UCMP continues to provide cost effective and efficient resource sharing in future years.

Catalogs as Topic↗
PubMed1998

Breaking the boundaries: collaborating to develop a model ventilator training program.

Changes in the health care system have created new opportunities for acute care nurses to establish collaborative relationships with their rehabilitation partners. When a rehabilitation facility decided to establish a ventilator weaning rehabilitation program, an acute care facility joined forces with the institution to develop an educational plan for the nursing staff. The development and implementation of the educational program as well as the collaborative relationship established between the two facilities are highlighted in this continuing education article.

Curriculum↗
PubMed1998

Basic concepts of functional arteriovenous MR imaging malformations.

This article reviews the technical features of functional MR imaging. Examples are presented demonstrating how MR imaging may be used to identify primary cortical regions adjacent to AVMs. Preliminary results suggest that cortical functions may undergo translocation when the AVM involves eloquent cortex. This finding underscores the importance of cortical mapping prior to surgical excision.

Brain Mapping↗
PubMed1998

Basic concepts of functional magnetic resonance imaging and arteriovenous malformations

Cortical mapping is an important adjunct to the workup of patients with arteriovenous malformation (AVMs) near eloquent cortical regions. Task activation imaging can be performed that clearly identifies primary cortical regions. Although current methods require considerable postprocessing, advances in hardware and software will likely make functional MR imaging a routing examination before surgical resection of AVMs in the near future.

Journal Article↗
PubMed1992

Reproducibility of noninvasive ultrasonic measurement of carotid atherosclerosis. The Asymptomatic Carotid Artery Plaque Study.

BACKGROUND AND PURPOSE: To determine the effect of a lipid-lowering agent and/or a low-dose antithrombotic agent on the progression of early-stage carotid atherosclerosis, noninvasive B-mode ultrasound was used to measure intimal-medial thickness in asymptomatic individuals with moderately elevated lipids as part of the ongoing multicenter Asymptomatic Carotid Artery Plaque Study. METHODS: Uniform ultrasonic scanning and reading protocols were implemented to obtain maximum intimal-medial thickness measurements in 12 standard segments in patients having a small to moderate wall thickness (1.5-3.5 mm) in at least one of the carotid arteries. Paired B-mode image recordings on 858 patients, performed 1 month apart and read at a core laboratory (each pair by the same reader), determined both within-sonographer (W, n = 405) and between-sonographer (B, n = 453) reproducibility. RESULTS: The primary end point (mean +/- SD), defined in each individual as the mean value of the 12 maximum intimal-medial thickness measurements, was 1.31 +/- 0.21 mm (W) and 1.32 +/- 0.22 (B) at the time of the second examination. The mean difference in the primary end point (exam 2-exam 1) was -0.01 +/- 0.13 mm (W) and 0.00 +/- 0.15 mm (B). The Pearson correlation coefficients were 0.79 (W) and 0.75 (B). In 90% of the patients, the absolute difference in the primary end point was less than 0.22 mm (W) and less than 0.24 mm (B). Variability of the secondary end point, defined as the single largest intimal-medial thickness measurement in a patient, was between three and four times larger than the variability for the primary end point. Differences in sonographer performance between clinical centers were very small. CONCLUSIONS: The results demonstrate that standardized noninvasive ultrasonic techniques yield highly reproducible measures of carotid intimal-medial thickness, which can serve as a measure of carotid atherosclerosis in clinical trials that monitor small rates of lesion progression.

Adult↗
PubMed1992

Assessing choice making among children with multiple disabilities.

Some learners with multiple disabilities display idiosyncratic gestures that are interpreted as a means of making choices. In the present study, we assessed the validity of idiosyncratic choice-making behaviors of 3 children with multiple disabilities. Opportunities for each child to choose between food and drink were provided under two conditions. In one condition, the children were given the food or drink item corresponding to their prior choice. In the other condition, the teacher delivered the item opposite to that chosen. It was reasoned that valid choice-making behaviors would be reflected in a greater tendency to accept the chosen item and refuse the unchosen item. Direct observations revealed all children consistently indicated choices during both conditions. Choices of both the food and drink items were made by all 3 children. A reversal design demonstrated that acts of refusal were more frequent when choices were followed by delivery of the item opposite to that chosen. Similar assessment procedures may be effective in determining the function of idiosyncratic gestures exhibited by persons with multiple disabilities. For children lacking such skills, intervention to teach valid choice-making behaviors may be needed to complement assessment procedures.

Child↗
PubMed1991

Altered gastric emptying in the head-injured patient: relationship to feeding intolerance.

Most patients with moderate to severe head injury initially do not tolerate enteral feedings postinjury. This intolerance is more prolonged than that found in patients suffering other types of trauma. The authors prospectively evaluated 12 patients with moderate to severe head injury (Glasgow Coma Scale score between 4 and 10) throughout their hospitalization for liquid gastric emptying as a possible mechanism for intolerance to enteral feeding. During Week 1, the majority of patients displayed a delay in gastric emptying. Patients also displayed an abnormal biphasic response (gastric emptying faster than normal during the early stage but prolonged later). By Week 2, many patients still had delayed and abnormal biphasic responses to gastric emptying. By Week 3, an improvement was observed with the majority of patients exhibiting rapid gastric emptying, but delays and abnormal biphasic responses were still seen. Patients who initially had rapid or normal gastric emptying tolerated full-strength full-rate feedings significantly earlier compared with those who experienced delayed gastric emptying (8.5 +/- 0.5 days vs. 13.7 +/- 3.2 days, p less than 0.001). All patients tolerated full-strength full-rate feedings by Day 16 postinjury (range 7 to 16 days) except the two patients who displayed delayed gastric emptying for prolonged periods of time (mean 25 days). This is the first study to longitudinally evaluate gastric emptying following head injury. The authors suggest that patients with moderate to severe head injury often experience alterations in gastric emptying which may affect their ability to tolerate enteral feedings.

Adolescent↗
PubMed1990

Leukocyte inhibitory factor activates human neutrophils and macrophages to release leukotriene B4 and thromboxanes.

Recent evidence has proved that cytokines can stimulate the production of 5-lipoxygenase products. Leukotriene B4 (LTB4) is a major mediator of leukocyte activation in acute inflammatory reactions, which produce chemotaxis, lysosomal enzyme release, and cell aggregation. Leukocyte inhibitory factor (LIF) also causes biological responses related to inflammation, i.e., LIF directly induces specific granule secretion by polymorphonuclears (PMNs) and potentiates many formyl-methionyl-leucyl-phenylalanine (FMLPs) mediated responses. Since arachidonic acid products are important mediators of inflammation, we have studied the effects of LIF on the arachidonic acid cascade products LTB4 and thromboxane A2 (TxA2). Resuspended at a final concentration of greater than 95% polymorphonuclear PMNs were isolated and tested with some cytokines on the release of LTB4 and TxA2. Peripheral blood mononuclear cells were isolated and seeded in Petri dishes and incubated for 60 min. Adherent macrophages were used for the cytokine stimulation study. Both types of leukocytes were treated with LIF, interleukin 6 (IL 6), and granulocyte-monocyte colony stimulating factor (GM-CSF) at different concentrations, and test agents A23187 and FMLP. Radioimmunoassay for LTB4 and TxB2 was determined by the resulting supernatants. Treatment of PMNs and macrophages with LIF at different concentrations proved to generate significant increases in LTB4 and TxA2 production. This was compared with IL 6 and GM-CSF, which had no effects. In these experiments, TxA2 generations could not be attributed to platelet contamination of PMN suspensions. The quantity of platelet contamination was not sufficient to influence how much TxB2 was produced. The similarities of LIF to other arachidonate stimulating cytokines suggest a similar mode of action in producing hematologic changes typical of tissue injury.(ABSTRACT TRUNCATED AT 250 WORDS)

Calcimycin↗
PubMed1989

Relationship between admission hyperglycemia and neurologic outcome of severely brain-injured patients.

Severe head injury is associated with a stress response that includes hyperglycemia, which has been shown to worsen outcome before or during cerebral ischemia. To better define the relationship between human head injury and hyperglycemia, glucose levels were followed in 59 consecutive brain-injured patients from hospital admission up to 18 days after injury. The patients who had the highest peak admission 24-hour serum glucose levels had the worse 18-day neurologic outcome (p = 0.01). Patients with peak 24-hour admission glucose levels greater than 200 mg/dL had a two-unit increase in Glasgow Coma Scale score while patients with admission peak 24-hour serum glucose levels less than or equal to 200 mg/dL had a four-unit increase in Glasgow Coma Scale score during the 18-day study period (p = 0.04). There was a significant relationship between 3-month and 1-year outcome and peak admission 24-hour serum glucose level (p = 0.02 and p = 0.02, respectively). Those patients with admission peak 24-hour serum glucose levels less than or equal to 200 mg/dL had a greater percentage of favorable outcome at 18 days, 3 months, and 1 year than those with admission peak 24-hour glucose levels greater than 200 mg/dL (p = 0.0007, p = 0.03, and p = 0.005, respectively). A significant relationship between admission peak 24-hour Glasgow Coma Scale score and 18-day, 3-month, and 1-year outcomes was found (p = 0.0001, p = 0.0002, and p = 0.0002, respectively). Patients with mean admission peak 24-hour Glasgow Coma Scale scores of 3.5, 6, and 10 had mean admission 24-hour peak serum glucose levels of 252 +/- 23.5, 219.1 +/- 19, and 185.8 +/- 21, respectively (p = 0.05). These relationships were not significantly altered when confounding variables such as the amount of glucose given over the initial 24-hour postinjury period, the presence of diabetes or multiple injuries, and whether patients were given steroids, dilantin, or insulin were statistically incorporated. These data suggest that admission hyperglycemia is a frequent component of the stress response to head injury, a significant indicator of severity of injury, and a significant predictor of outcome from head injury.

Analysis of Variance↗
PubMed1988

Prophylactic parenteral antibiotics in clean neurosurgical procedures: a review.

Clean surgical procedures carry a risk of postoperative wound infection that is less than 5% in most hospitals. The use of prophylactic antibiotic agents in clean neurosurgical cases is controversial, and the neurosurgical literature through 1980 contains no controlled clinical trials to study its effectiveness in such cases. A report of 1732 consecutive procedures without a single postoperative wound infection in patients receiving systemic gentamicin, vancomycin, and streptomycin irrigation fluids is often quoted by neurosurgeons; however, these results have not yet been duplicated by others. Since 1980, there have been several controlled trials that support the use in clean neurosurgical cases of prophylactic antibiotics, including the vancomycin/gentamicin/streptomycin regimen and the first-generation cephalosporins. A report in 1986 of 1602 cases without a primary wound infection supports the use of a single perioperative dose of cefazolin. A review of causative organisms in postoperative wound infections demonstrates the preponderance of Gram-positive pathogens. Therefore, when antibiotic prophylaxis is indicated, adequate Gram-positive bacterial coverage, including protection against Staphylococcus infection, is required. With consideration of the present data, the cost of antibiotic therapy, and the danger of drug toxicity, a short perioperative regimen of cefazolin as prophylaxis is preferred in clean neurosurgical cases.

Anti-Bacterial Agents↗
PubMed1987

Effect of total parenteral nutrition upon intracranial pressure in severe head injury.

Animal investigations suggest that administration of hyperosmolar total parenteral nutrition (TPN) solutions may potentiate cerebral edema following head injury. Intravenous nutrition (TPN) is often required after head injury due to intolerance to enteral feeding (EN). This study evaluates the effect of TPN on intracranial pressure (ICP) measurements in severely brain-injured patients. Ninety-six severely brain-injured patients were randomly assigned to receive TPN or EN and were studied from hospital admission until 18 days postinjury. The TPN was started within 48 hours postinjury and the EN was started when tolerated. Peak daily ICP was not significantly different on admission and over time (overall mean +/- standard error of the mean 32.01 +/- 1.62 for TPN versus 32.5 +/- 1.25 for EN). Intracranial pressure was greater than 20 mm Hg in 75% of TPN patients and 73% of EN patients. Conventional therapy failed to control elevated ICP in 36% of TPN patients and 38% of EN patients. Of these patients, subsequent barbiturate therapy failed to control ICP in 56% of TPN patients and 64% of EN patients. Serum osmolality was not significantly different between groups at admission or over the course of the study. The TPN group tended to have higher mean serum glucose levels for the first 13 days postinjury, while the EN group had a higher mean serum glucose content thereafter, but these differences were not statistically significant. This study shows that TPN can be given safely to the severely brain-injured patient without causing serum hyperosmolality or affecting ICP levels or ICP therapy.

Brain Injuries↗
PubMed1987

The effect of nutritional support on outcome from severe head injury.

Fifty-one brain-injured patients with peak 24-hour admission Glasgow Coma Scale (GCS) scores of 4 to 10 were prospectively randomly assigned to receive total parenteral (TPN) or enteral (EN) nutrition. Patients were studied from hospital admission to 18 days postinjury. Outcome was assessed by the Glasgow Outcome Scale at 3 months, 6 months, and 1 year postinjury. The TPN group received a significantly higher cumulative mean intake of protein than the EN group (mean +/- standard error of the mean: 1.35 +/- 0.12 vs. 0.91 +/- 0.9 gm/kg/day; p = 0.004). Mean cumulative caloric balance was also significantly higher in the TPN than in the EN group (75.6% +/- 5.13% vs. 59% +/- 4.26%; p = 0.02). Nitrogen balance was significantly more negative in the EN group during the 1st week postinjury (p = 0.002). The incidence of pneumonia, urinary tract infections, septic shock, and infections was not significantly different between groups. Classic nutritional assessment parameters such as anergy screens, total lymphocyte counts, and albumin levels were not significantly different between groups. The 11 patients in the EN group who did not tolerate tube feedings for 1 week postinjury had a significantly higher incidence of septic shock (p = 0.008). The change over time in GCS scores between groups was significantly different, with the TPN group showing a mean four-point increase in GCS score compared with a three-point increase in the EN group (p = 0.02). At 3 months the TPN group had a significantly higher percentage of favorable outcomes (43.5% vs. 17.9%, respectively; p = 0.05). At 6 months, 43.5% of the TPN group had a favorable outcome while 32.1% of the EN group had a favorable outcome (p = 0.29). By 1 year, 47.8% of the TPN group and 32.1% of the EN group had a favorable outcome (p = 0.20). In conclusion, more calories and protein usually can be administered to acute brain injury patients via the TPN route than by EN feedings via nasogastric or nasoduodenal routes. Traditional parameters for nutritional assessment are not useful in studying the efficacy of nutritional support during the first 2 weeks after head injury. Neurological recovery from head injury occurs more rapidly in patients with better early nutritional support.

Craniocerebral Trauma↗
PubMed1985

Metabolic and nutritional sequelae in the non-steroid treated head injury patient.

Energy production, substrate oxidation, serum protein levels, and weight change were studied in 16 non-steroid treated patients with severe head injury. Patients were evaluated during an average of 31.3 days from hospital admission to discharge. The mean measured energy expenditure (MEE) was 1.40 +/- 0.5 times predicted energy expenditure. Caloric balance [calories received = calories expended] was achieved by the 2nd week. Despite caloric balance and the administration of at least 1.5 g of protein per kg of body weight per day, the mean nitrogen balance was negative. There was a positive nitrogen balance in only 2 patients. These patients received a mean of 1.43 times the MEE in total kilocalories and 2.3 g of protein per kg of body weight. Fat and protein oxidation exceeded protein and fat administration for 3 weeks postinjury. Albumin levels dropped from a mean of 3.09 +/- 0.2 on admission to 1.98 +/- 0.4 within 2 weeks. The initial retinol binding protein levels were within the normal range, and the levels increased over time. There was marked weight loss (mean, 15.6 +/- 5.9 lb). Head injury induces a profound traumatic response identified by increased energy expenditure, a negative nitrogen balance, weight loss, hypoalbuminemia, and altered substrate oxidation. This response seems to be caused by the head injury alone and is not due to the administration of corticosteroids.

Adolescent↗
PubMed1975

Reduction of enzyme efflux from skeletal muscle by diethylstilbestrol.

We have previously shown that oral diethylstilbestrol (DES) lowers the high serum enzyme levels characteristic of Duchenne's muscular dystrophy (DMD). The present studies were undertaken to assess the effect of DES on the efflux of enzymes from isolated mouse skeletal muscle. Thirty-four male mice were used. Half received daily subcutaneous injections of 10 mug diethylstilbestrol-diphosphate (DES-DP) in saline for up to 3 wk and half daily saline injections. Left gastrocnemii were isolated from control and treated mice, and placed in separate incubation media at 37 degrees C. The efflux of creatine phosphokinase (CPK) and lactate dehydrogenase (LDH) from each was compared over a 4- to 5-hr period. In 15 of 18 there was a reduction in efflux of both enzymes from muscles isolated from DES-DP-treated mice. The greatest effect was noted during the second hour, when the mean efflux of each enzyme was reduced about 30%. Minor differences in muscle weight, water content, and enzyme activities did not explain the reduced efflux. These results suggest that DES has either reduced the permeability of the sarcolemma or enhanced the intracytoplasmic stability of these enzymes. This is the first drug reported to reduce the spontaneous enzyme efflux from isolated skeletal muscle. It remains to be established that a similar effect accounts for the reduction in serum enzyme levels when DES is administered to persons with DMD.

Animals↗
PubMedDate not supplied

Comparison of urinary urea nitrogen excretion and measured energy expenditure in spinal cord injury and nonsteroid-treated severe head trauma patients.

Severe head trauma patients (HT) exhibit markedly elevated energy expenditure and 24-hr urinary urea nitrogen excretion (UUN) values. The objective of this study was to compare seven spinal cord injured patients (SCI) to seven HT for changes in UUN and measured energy expenditure (MEE) over the first 18 days following injury. Energy expenditure was measured by indirect calorimetry and compared to values predicted by the Harris Benedict Equation (PEE). There were six quadriplegics and one paraplegic in the SCI group. HT patients had peak Glasgow Coma Scale scores of 3 to 10 for the first 24 hr postinjury. Patients were studied prospectively and matched for age, sex, and admitting weight Week 1 following the injury, SCI had mean UUN values of 0.18 +/- 0.04 g/kg/day vs 0.18 +/- 0.01 for HT patients. The mean MEE/PEE ratio was 0.56 for the SCI and 1.4 for HT (p less than 0.01). Over the entire study period the mean UUN value for SCI was 0.23 +/- 0.03 g/kg vs 0.21 +/- 0.01 for HT. The mean MEE/PEE ratio for SCI was 0.94 while HT remained elevated at 1.5 (p less than 0.05). Although the UUN was comparable in SCI vs HT, there was a significant difference in MEE/PEE between the groups. The elevation in UUN observed in SCI is not due to a hypermetabolic state. This suggests that different mechanisms promote the increased nitrogen excretion observed in these two populations.

Acute Disease↗