Biomedical subjects

C D Smith

Publications and source records attributed to C D Smith.

At least 55 records · Page 3Linked to original sources

PubMed2001

Nissen fundoplication improves gastric motility in patients with delayed gastric emptying.

BACKGROUND: Fundoplication hastens gastric emptying in pediatric patients with gastroesophageal reflux disease (GERD). However, among adult GERD patients with impaired gastric emptying, the degree of improvement offered by fundoplication and the value of pyloroplasty are less well defined. Therefore, we compared outcomes in GERD patients with delayed gastric emptying after fundoplication alone or fundoplication with pyloroplasty. METHODS: Of 616 consecutive GERD patients who submitted to primary fundoplication (601 laparoscopic) between October 1991 and October 1997, 82 underwent preoperative solid-phase nuclear gastric emptying analysis. Of these, 25 had delayed gastric emptying (half-time >100 min). Of 12 patients with emptying half-times between 100 and 150 min, one underwent pyloroplasty at the time of Nissen fundoplication. Of 13 patients with emptying half-times >150 min, 11 had pyloroplasty at the time of Nissen fundoplication. Patients were asked to use a 0 ("none") to 4 ("incapacitating") scale to describe the severity of their symptoms of heartburn, regurgitation, dysphagia, bloating and diarrhea preoperatively and at 6 weeks and 1 year postoperatively. Eight patients consented to a postoperative analysis of gastric emptying. RESULTS: One year after fundoplication, patients with delayed gastric emptying and controls reported a similar improvement in heartburn, regurgitation, and dysphagia, with no increase in undesirable side effects such as bloating and diarrhea. Among the patients with delayed gastric emptying who consented to undergo a repeat gastric emptying study after their operation, fundoplication alone provided a 38% improvement (p < 0.05) in gastric emptying, whereas fundoplication with pyloroplasty resulted in a 70% improvement in gastric emptying (p < 0.05). CONCLUSION: Fundoplication improves gastric emptying. The addition of pyloroplasty results in even greater improvement and may have particular value for patients with severe gastric hypomotility.

Adolescent↗

PubMed2001

A randomized, controlled trial of methotrexate versus placebo in early diffuse scleroderma.

OBJECTIVE: Early diffuse scleroderma (systemic sclerosis; SSc) has no proven treatment. This study was undertaken to examine the efficacy of methotrexate (MTX) in improving the skin and other disease parameters in early diffuse SSc. METHODS: Seventy-one patients with diffuse SSc of <3 years' duration were enrolled in a multicenter, randomized, placebo-controlled, double-blind trial. Thirty-five patients were treated with MTX and 36 with placebo. Treatment was administered for 12 months. The primary outcome measures were skin score (as determined with 2 different indices) and physician global assessment. RESULTS: At baseline, there were no statistically significant differences in skin scores, carbon monoxide diffusing capacity (DLco), physician global assessment, or other secondary outcome measurements between the 2 treatment groups. At study completion, results slightly favored the MTX group (mean +/- SEM modified Rodnan skin score 21.4+/-2.8 in the MTX group versus 26.3+/-2.1 in the placebo group [P < 0.17]; UCLA skin score 8.8+/-1.2 in the MTX group versus 11.0+/-0.9 in the placebo group [P < 0.15]; DLco in the MTX group 75.7+/-4.6 versus 61.8+/-3.4 in the placebo group [P < 0.2]). In addition, physician global assessment results favored MTX (P < 0.035), whereas patient global assessment did not differ significantly between groups. When between-group differences for changes in scores from baseline to 12 months were examined using intent-to-treat methodology, MTX appeared to have a favorable effect on skin scores (modified Rodnan score -4.3 in the MTX group versus 1.8 in the placebo group [P < 0.009]; UCLA score -1.2 in the MTX group versus 1.2 in the placebo group [P < 0.02]), but differences in the degree of change in the DLco and physician global assessment were not significant. For the UCLA skin score, these differences in results were not statistically significant after adjustment for baseline differences in sex distribution and steroid use. Dropout rates were similar in the 2 groups. CONCLUSION: Although results of this trial demonstrated a trend in favor of MTX versus placebo in the treatment of early diffuse SSc, the between-group differences were small and the power to rule out false-negative results was only 50%. Our findings do not provide evidence that MTX is significantly effective in the treatment of early diffuse SSc.

Disability Evaluation↗

PubMed2001

Are the favorable outcomes of splenectomy predictable inpatients with idiopathic thrombocytopenic purpura (ITP)?

BACKGROUND: Historically, splenectomy has been an accepted procedure in the management of immune thrombocytopenic purpura (ITP). However, it is also true that the response to splenectomy in patients with ITP seems to be unpredictable. Therefore, the purpose of this study was to identify clinical variables that might predict a favorable response to splenectomy in patients with ITP. METHODS: Data were collected retrospectively for 40 adult patients with ITP who underwent laparoscopic (LS) and open (OS) splenectomy at Emory University Hospital between 1992 and 1999. Demographics and outcomes were recorded. Age, sex, disease duration, comorbidities (ASA > 2), previous response to steroids and/or other medications, and preoperative platelet count were analyzed by univariate (t-test, Fisher's exact test) and multivariate statistical methods. RESULTS: Of the 20 patients in each group, improved platelet counts were noted in 18 patients (90%) in the LS group and 20 patients (100%) in the OS group. Follow-up (16 +/- 3 months) was obtained in 19 LS patients (95%) and 16 OS patients (80%), with 84% and 87.5% sustained response rates, respectively. After univariate analysis, two variables (age and disease duration) were found to be significantly related to the outcome of splenectomy (p <lt; 0.01). However, after multiple logistic regression analysis, only disease duration (relative risk = 1.083; CI, 1.004-1.167) was an independent prognostic factor for a sustained response to splenectomy. CONCLUSION: These results suggest that the response to splenectomy (laparoscopic and open) in patients with ITP cannot be adequately predicted on the basis of presplenectomy clinical variables. However, disease duration and patient age should be taken into consideration when selecting patients for splenectomy.

Adult↗

PubMed2001

A computer-based laparoscopic skills assessment device differentiates experienced from novice laparoscopic surgeons.

BACKGROUND: The acquisition of laparoscopic skills is difficult to assess. Previously, through the use of a computer-based skills assessment device (SAD), we have shown that assessments of the time needed to perform a task and graded observations of task performance overestimate the speed at which laparoscopic skills can be acquired. The aim of this study was to test the ability of a laparoscopic SAD to differentiate novices from experienced laparoscopic surgeons and thereby further validate its use in surgical education. METHODS: Using a laparoscopic simulator platform integrated with task simulation and data collection software (MIST VR), we tested both experienced and novice laparoscopists. Each group performed three tasks with a minimum of seven repetitions. The tasks consisted of target acquisition, target traversal, and target manipulation with diathermy. Within each task, time (T), errors (E), and economy of movement for each hand (EML, EMR) were assessed. Results were reported as mean +/- SEM, and comparisons were made using an independent samples t-test. RESULTS: For the target acquisition task, the expert group performed the task faster than the novice group (5.5 +/- 0.24 vs 7.6 +/- 0.40 sec, p < 0.05); the experts also made fewer errors (0.5 +/- 0.10 vs 0.8 +/- 0.11 errors, p < 0.05), and achieved both a better EML (1.8 +/- 0.6 vs 2.3 +/- 0.9, p < 0.05) and a better EMR (2.0 +/- 0.1 vs 2.9 +/- 0.21, p < 0.05). In the target traversal task, the experts made fewer errors than the novices (2.2 +/- 0.25 vs 4.6 +/- 0.38 errors, p < 0.05). For the manipulation and diathermy tasks, the expert group completed the task faster (30.8 +/- 1.5 vs 39 +/- 1.5 sec, p < 0.05), made fewer errors (5.3 +/- 0.59 vs 8.1 +/- 0.63 errors, p < 0.05), and had a better EML (6.0 +/- 0.37 vs 7.2 +/- 0.45, p < 0.05) and EMR (4.3 +/- 0.23 vs 5.8 +/- 0.36, p < 0.05) than the novices. CONCLUSION: A laparoscopic skills assessment device can discern levels of laparoscopic manipulative skill. This type of device can be used in surgical training to make objective assessments of the acquisition of laparoscopic skills.

Clinical Competence↗

PubMed2001

Assessing laparoscopic manipulative skills.

BACKGROUND: The rapid emergence of laparoscopic surgery over the past decade has highlighted the need for teaching and assessing laparoscopic manipulative skills. Most analyses consist of a measurement of the time to complete a specified task and a subjective assessment by an observer. Objective assessments of accuracy in the performance of manipulative skills have been lacking. To quantify both speed and accuracy during laparoscopic skill performance, we have developed a skills assessment device (SAD) using a laparoscopic simulator platform and computer-based skills assessment software that precisely measures an instrument's movement during performance of timed laparoscopic manipulations. STUDY DESIGN: The SAD device measures the time necessary for an operator to complete a task, and the movements of the working end of laparoscopic instruments in three dimensions. Ten nonsurgeons performed 10 repetitions of a standardized laparoscopic manipulation. Data were captured in real time for both hands on a personal computer. Accuracy was determined by calculating the sum of all distances traveled. Duration was measured in seconds. Results are group means. RESULTS: The time necessary to perform defined laparoscopic manipulative skills improved dramatically during the first 3 repetitions and then stabilized. However, accuracy of manipulations continued to improve over all 10 repetitions. CONCLUSIONS: When untrained subjects are learning a laparoscopic manipulative task, measurement of time alone fails to account for the more protracted learning curve for accuracy. Therefore, devices and training programs that fail to consider objective assessments of accuracy may overestimate laparoscopic proficiency.

Clinical Competence↗

PubMed2001

Neural substrates of facial emotion processing using fMRI.

We identified human brain regions involved in the perception of sad, frightened, happy, angry, and neutral facial expressions using functional magnetic resonance imaging (fMRI). Twenty-one healthy right-handed adult volunteers (11 men, 10 women; aged 18-45; mean age 21.6 years) participated in four separate runs, one for each of the four emotions. Participants viewed blocks of emotionally expressive faces alternating with blocks of neutral faces and scrambled images. In comparison with scrambled images, neutral faces activated the fusiform gyri, the right lateral occipital gyrus, the right superior temporal sulcus, the inferior frontal gyri, and the amygdala/entorhinal cortex. In comparisons of emotional and neutral faces, we found that (1) emotional faces elicit increased activation in a subset of cortical regions involved in neutral face processing and in areas not activated by neutral faces; (2) differences in activation as a function of emotion category were most evident in the frontal lobes; (3) men showed a differential neural response depending upon the emotion expressed but women did not.

Adult↗

PubMed2001

Response of atypical symptoms of gastro-oesophageal reflux to antireflux surgery.

BACKGROUND: Atypical manifestations of gastro-oesophageal reflux (GOR) include asthma, chest pain, cough and hoarseness. The effectiveness of antireflux surgery for these symptoms is uncertain. The present study compared symptomatic response rates for typical and atypical GOR symptoms after fundoplication. METHODS: Between October 1991 and January 1998, 324 patients underwent laparoscopic fundoplication at Emory University Hospital and returned postoperative questionnaires. Severity of typical (heartburn) and atypical (asthma, chest pain, cough and hoarseness) GOR symptoms was reported by patients on a 0-4 scale before surgery, and at 6 and 52 weeks after operation. Patients were stratified based on preoperative symptoms into three groups: group 1 (severe heartburn/minimal atypical symptoms), group 2 (severe heartburn/severe atypical symptoms) and group 3 (minimal heartburn/severe atypical symptoms). RESULTS: In group 1 (n = 173) heartburn improved in 99 per cent and resolved in 87 per cent. In group 2 (n = 95) heartburn improved in 95 per cent and resolved in 76 per cent, and atypical symptoms improved in 94 per cent and resolved in 42 per cent. In group 3 (n = 56) atypical symptoms improved in 93 per cent and resolved in 48 per cent. Although all symptoms were improved by fundoplication, resolution was more likely for heartburn than for atypical symptoms. CONCLUSION: Atypical symptoms of GOR are improved by fundoplication, but symptom resolution occurs in fewer than 50 per cent of patients.

Asthma↗

PubMed2001

Urban-rural differences in a memory disorders clinical population.

OBJECTIVES: To compare patient characteristics and family perceptions of patient function at one urban and one rural memory disorders clinic. DESIGN: Secondary, cross-sectional data analyses of an extant clinical database. SETTING/PARTICIPANTS: First time visits (n = 956) at two memory disorders clinics. MEASUREMENTS: Patient and family-member demographics and assessment results for the Mini-Mental State Examination (MMSE), instrumental activities of daily living (IADLs), activities of daily living (ADLs), the Memory Change and Personality Change components of the Blessed Dementia Rating Scale, and the Revised Memory and Behavior Problems Checklist. RESULTS: In both clinics, patients and family members were more likely female. The typical urban clinic patient was significantly more likely to be living in a facility and more educated than the typical rural patient. Urban and rural patients did not show significant differences in age- and education-adjusted MMSE scores or raw ADL/IADL ratings, but the urban family members reported more memory problems, twice as many personality changes, more-frequent behavior problems, and more adverse reactions to problems. CONCLUSION: Physicians who practice in both urban and rural areas can anticipate differences between patients, and their families, who seek a diagnosis of memory disorders. Our most important finding is that despite similarities in reported functional abilities, urban families appear to be more sensitive to and more distressed by patients' cognitive and behavioral symptoms than rural families. These differences may reflect different underlying needs, and should be explored in further research.

Activities of Daily Living↗

PubMed2001

A prospective randomized comparison of laparoscopic appendectomy with open appendectomy: Clinical and economic analyses.

BACKGROUND: Previous randomized studies of laparoscopic appendectomy produced conflicting recommendations, and the adequacy of sample sizes is generally unknown. We compared clinical and economic outcomes after laparoscopic and open appendectomy in a sample of predetermined statistical power. METHODS: A pre-study power analysis suggested that 200 randomized patients would yield 80% power to show a mean decrease of 1.3 days' hospitalization. One hundred ninety-eight patients with a preoperative diagnosis of acute appendicitis were randomized prospectively to laparoscopic or open appendectomy. Economic analysis included billed charges, total costs, direct costs, and indirect costs associated with treatment. RESULTS: Laparoscopic appendectomy took longer to perform than open appendectomy (median, 107 vs 91 minutes; P <.01) and was associated with fewer days to return to a general diet (mean, 1.6 versus 2.3 days; P <.01), a shorter duration of parenteral analgesia (mean, 1.6 versus 2.2 days; P <.01), fewer morphine-equivalent milligrams of parenteral narcotic (median, 14 mg versus 34 mg; P =.001), a shorter postoperative hospital stay (mean, 2.6 versus 3.4 days; P <.01), and earlier return to full activity (median, 14 versus 21 days; P <.02). However, operative morbidity and time to return to work were comparable. Billed charges and direct costs were not significantly different in the 2 groups ($7711 versus $7146 and $5357 versus $4945, respectively), but total costs (including indirect costs) of laparoscopic appendectomy were, on average, nearly $2400 less, given the shorter length of stay and abbreviated recuperative period ($11,577 versus $13,965). Subgroup analyses suggested the benefit of a laparoscopic approach for uncomplicated appendicitis and for patients with active lifestyles. CONCLUSIONS: While laparoscopic appendectomy is associated with statistically significant but clinically questionable advantages over open appendectomy, a laparoscopic approach is relatively less expensive. The estimated difference in total costs of treatment (direct and indirect costs) was at least $2000 in more than 60% of the bootstrapped iterations. The economic significance and implications favoring a laparoscopic approach cannot be ignored.

Appendectomy↗

PubMed2001

Bile duct injury during laparoscopic cholecystectomy: results of a national survey.

OBJECTIVE: To determine whether surgical residency training has influenced the occurrence of common bile duct injuries during laparoscopic cholecystectomy, and to asses the anatomic and technical details of bile duct injuries from the practices of surgeons trained in laparoscopic cholecystectomy after residency versus surgeons trained in laparoscopic cholecystectomy during residency. SUMMARY BACKGROUND DATA: Shortly after the introduction of laparoscopic cholecystectomy, the rate of injury to the common bile duct increased to 0.5%, and injuries were more commonly reported early in each surgeon's experience. It is not known whether learning laparoscopic cholecystectomy during surgery residency influences this pattern. METHODS: An anonymous questionnaire was mailed to 3,657 surgeons across the United States who completed an Accreditation Council for Graduate Medical Education (ACGME)-approved residency between 1980 and 1990 (group A) or 1992 and 1998 (group B). All surgeons in group A learned laparoscopic cholecystectomy after residency, and all those in group B learned laparoscopic cholecystectomy during residency. Information obtained included practice description, number of laparoscopic cholecystectomies completed since residency, postgraduate training in laparoscopy, and annual volume of laparoscopic cholecystectomy in the surgeon's hospital. In addition, technical details queried included the completion of a cholangiogram, the interval between injury and identification, the method of repair, and the site of definitive treatment. The primary endpoint was the occurrence of a major bile duct injury during laparoscopic cholecystectomy (bile leaks without a major bile duct injury were not tabulated). RESULTS: Forty-five percent (n = 1,661) of the questionnaires were completed and returned. Mean practice experience was 13.6 years for group A and 5.4 years for group B. At least one injury occurrence was reported by 422 surgeons (37.6%) in group A and 143 surgeons (26.5%) in group B. Forty percent of the injuries in group A occurred during the first 50 cases compared with 22% in group B. Thirty percent of bile duct injuries in group A and 32.9% of all injuries in group B occurred after a surgeon had performed more than 200 laparoscopic cholecystectomies. Independent of the number of laparoscopic cholecystectomies completed since residency, group A surgeons were 39% more likely to report one or more biliary injuries and 58% more likely to report two or more injuries than their counterparts in group B. Bile duct injuries were more likely to be discovered during surgery if a cholangiogram was completed than if cholangiography was omitted (80.9% vs. 45.1%). Sixty-four percent of all major bile duct injuries required biliary reconstruction, and most injuries were definitively treated at the hospital where the injury occurred. Only 14.7% of injuries were referred to another center for repair. CONCLUSIONS: Accepting that the survey bias underestimates the true frequency of bile duct injuries, residency training decreases the likelihood of injuring a bile duct, but only by decreasing the frequency of early "learning curve" injuries. If one accepts a liberal definition of the learning curve (200 cases), it appears that at least one third of injuries are not related to inexperience but may reflect fundamental errors in the technique of laparoscopic cholecystectomy as practiced by a broad population of surgeons in the United States. Intraoperative cholangiography is helpful for intraoperative discovery of injuries when they occur. Most injuries are repaired in the hospital where they occur and are not universally referred to tertiary care centers.

Adult↗

PubMed2001

Crystallization and preliminary X-ray diffraction analysis of protein L-isoaspartyl O-methyltransferase from wheat germ.

Wheat-germ protein L-isoaspartyl O-methyltransferase (WPIMT) can initiate the conversion of L-isoaspartyl residues in a protein or peptide, which accumulate during the aging process in wheat-germ seeds, to normal L-aspartyl groups. The recombinant protein of WPIMT was overexpressed in Escherichia coli and purified to homogeneity. The protein was crystallized in the presence of S-adenosine-L-homocysteine using 2-methyl-2,4-pentanediol. Preliminary X-ray analysis indicated a tetragonal space group P4(1)2(1)2 or P4(3)2(1)2, with unit-cell parameters a = b = 77.3, c = 152.9 A for cryofrozen crystals at 90 K. The crystals diffracted to 3.3 A and contain two molecules per asymmetric unit.

Cloning, Molecular↗

PubMed2001

Differences in functional magnetic resonance imaging activation by category in a visual confrontation naming task.

OBJECTIVE: Cortical processing involved in seemingly similar tasks may differ in important ways. The authors mapped cortical regions engaged in a commonly performed picture naming task, seeking differences by semantic category. Functional magnetic resonance imaging was used during presentation of standardized line drawings in 18 healthy right-handed female participants, comparing living versus nonliving entities. During visual naming, across categories there was strong activation of left frontal (BA45/47), bilateral temporo-occipital junction (BA19), and inferior temporal regions (BA36/37). Activation of right inferior temporal cortex (BA19 and BA37) was greater during naming of living versus nonliving category items. No category differences in activation strength in the left temporal lobe were observed. The authors conclude that visual semantic operations may involve visual association cortex in the right temporal lobe in women.

Brain Mapping↗

PubMed2001

Genital infection and termination of pregnancy: Are patients still at risk?

OBJECTIVES: To identify the treatment patterns and early complication rates in women identified with a genital infection prior to a termination of pregnancy (TOP) and to re-assess our earlier work on contact attendance and treatment. The aim was to refine current prophylactic measures to provide the most efficient and effective way of reducing post-termination complications. METHOD: Six-month retrospective analysis of all women with genital Chlamydia trachomatis or Neisseria gonorrhoeae identified prior to TOP. Data on the timing of positive results and treatment in relation to the TOP were recorded. Clinical signs of pelvic infection and the success of contact tracing and treatment were noted. RESULTS: Forty women were identified with infection, 31 (78%) proceeded to TOP; only five were treated adequately in the peri-TOP period. Twenty-six (84%) of the women undergoing TOP attended the genitourinary medicine (GUM) department after the TOP and received antimicrobial therapy where necessary. In total, four women (10%) were untreated. Approximately two thirds of results were reported prior to, or on the day of, the TOP. The majority of TOPs (71%) were carried out at 5 days or less from the initial assessment. Clinical signs of post-TOP pelvic inflammation developed in seven (28%) women with chlamydial infection. Contact tracing was successful in 24 (69%) of the 35 women who attended the GUM department. CONCLUSION: The debate about the best option for the most effective management of women undergoing TOP continues. The options with respect to C. trachomatis include universal prophylaxis, screening and treating as necessary, or a 'belt and braces' approach of screening all and treating all. Fundamental is the continuation of active contact tracing and GUM remains integral to this.

Abortion, Induced↗

PubMed2001

National market cow and bull beef quality audit-1999: a survey of producer-related defects in market cows and bulls.

The 1999 National Market Cow and Bull Beef Quality Audit comprised face-to-face interviews with industry representatives (n = 49); in-plant evaluations of cattle in holding pens (n = 3,969), carcasses on harvest floors (n = 5,679), and in carcass coolers (n = 4,378); and a strategy workshop. Face-to-face interviews suggested that the beef industry was most frequently concerned about the presence of antibiotic residues in carcasses, presence of lead shot in carcasses, and price discovery for carcasses following excessive trimming of bruises and testing due to arthritic joints, pathogens, or antibiotic residues. Although live animal evaluations determined that 73.4% of beef cows, 60.8% of dairy cows, 63.7% of beef bulls, and 70.9% of dairy bulls did not exhibit evidence of lameness, losses due to lameness were greater (P < 0.05) than in the 1994 National Non-Fed Beef Quality Audit. In-plant audits revealed that 88.9, 10.3, and 88.2% of cow carcasses and 18.9, 21.2, and 52.9% of bull carcasses had inadequate muscling, arthritic joints, and at least 1 bruise, respectively, all of which resulted in greater (P < 0.05) losses than the same defects in 1994. Audits revealed that 88.9% of cow carcasses and 18.9% of bull carcasses were lightly muscled, resulting in greater (P < 0.05) losses for cow carcasses, and similar (P > 0.05) losses for bull carcasses, than the same defect in the 1994 audit. Also, 14.5 and 30.8% of cow carcasses and 6.9 and 5.9% of bull carcasses had excess external fat and yellow-colored external fat, respectively, which was an improvement (P < 0.05) over 1994 results. In aggregate, 24.1, 19.2, 7.2, 6.7, 9.5, and 1.1% of livers, tripe, hearts, heads, tongues, and whole cattle or carcasses, respectively, were condemned and 60.6, 2.4, and 46.5% of cattle had hide damage from latent defects, insect damage, and brands, respectively. Condemnation rates were generally lower (P < 0.05), but tongue condemnations and frequency of branded hides were higher (P < 0.05) than in 1994. Producers should promote value in cows and bulls by managing to minimize quality defects, monitoring health and condition, and marketing in a timely manner. Using these techniques, producers might have recaptured $13.82, $27.50, and $27.50, respectively, for each cow or bull harvested in 1999.

Animal Husbandry↗

PubMed2001

An automated technique for measuring hippocampal volumes from MR imaging studies.

We describe an automated volumetric measure of the hippocampus obtained with software called the Knowledge-Guided MRI Analysis Program (KGMAP). Postmortem MR images from 56 participants in the Nun Study were used to validate the measure. KGMAP-determined volumes strongly correlated with those obtained with manual tracings and neurofibrillary pathologic findings of Alzheimer disease in the hippocampus. KGMAP provides a rapid and accurate estimate of hippocampal volume that is suitable for use in clinical practice.

Alzheimer Disease↗

PubMed2001

The effect of low dose methotrexate on bone density.

OBJECTIVE: High dose methotrexate (MTX) has been linked with bone loss in oncology patients. However, it is unclear whether longterm low dose MTX used in the treatment of inflammatory arthritis is associated with bone loss. We compared the effect of low dose MTX on bone density in prospectively recruited patients with rheumatoid arthritis (RA) and psoriasis/psoriatic arthritis (Ps/PsA). METHODS: Thirty RA patients and 30 Ps/PsA patients taking MTX were compared to controls not taking MTX (30 with RA, 27 Ps/PsA). Bone mineral density (BMD) of the radius, lumbar spine, trochanter, and femoral neck was measured using Lunar dual energy x-ray absorptiometry. Student t tests were used to detect differences in bone density (using Z scores) of the MTX group versus controls for both the RA and Ps/PsA groups. Analysis of covariance was used to examine for confounders including disease duration, disease activity, age, and sex. RESULTS: BMD of the radius/femoral neck/trochanter did not differ significantly between the MTX treated groups and controls when analyzed by Z scores. The mean difference between the MTX group and controls of the femoral neck was 0.040 (95% CI -0.40, 0.12) and 0.060 (95% CI -0.30, 0.15) for the RA and Ps/PsA groups, respectively. The absolute BMD of the lumbar spine (L2-L4) was higher in the RA MTX group than in controls. Analysis of covariance did not reveal an effect of study group on bone density. CONCLUSION: This study suggests that low dose MTX does not have a negative effect on bone density, at either cortical or trabecular sites.

Absorptiometry, Photon↗

PubMed2001

Effects of a weaning protocol on ventilated pediatric intensive care unit (PICU) patients.

As part of a learning collaborative sponsored by the Center for the Evaluative Clinical Sciences (CECS) at Dartmouth College, a multidisciplinary pediatric intensive care unit (PICU) group began meeting in 1997 to evaluate potential performance improvement (PI) opportunities. A reduction in mechanical ventilation (MV) hours was the initial team focus. The multidisciplinary team developed and implemented protocols and physician order sets outlining care for MV weaning, neuromuscular blockade/therapeutic paralyzation, and enteral feedings. Since the initiation of our protocols in July 1997, we have significantly reduced the number of hours our PICU patients receive MV.

Algorithms↗

PubMed2000

"Preclinical" AD revisited: neuropathology of cognitively normal older adults.

OBJECTIVE: To classify neuropathologic alterations in the brains of nondemented older adults using current sets of criteria for AD. BACKGROUND: AD neuropathologic alterations are found in the brains of some nondemented elderly subjects and suggest the possibility of presymptomatic AD. Three sets of guidelines have been developed to classify AD using senile plaques, neuritic plaques, and neurofibrillary tangles (NFT). METHODS: Neuropathologic changes in 59 older adults followed longitudinally with a standard battery of mental status measures were investigated using Khachaturian, Consortium to Establish a Registry for Alzheimer's Disease (CERAD), and National Institute on Aging-Reagan Institute (NIA-RI) guidelines. AD neuropathologic markers were evaluated in neocortical and allocortical regions. Cases were categorized as neuropathologically "normal" or "AD-like" and compared for possible mental status differences. RESULTS: Between 11 and 49% of cases met one or more of the three classifications of AD. With adjustments for multiple comparisons, only NFT in hippocampal CA1 region were associated with autopsy age, suggesting that this may represent a pathologic process associated with normal brain aging. Using the NIA-RI guidelines, subjects in the AD-like group performed less well on the immediate paragraph recall and word-list delayed recall than their counterparts who did not meet these guidelines. CONCLUSIONS: These data indicate that the prevalence of "preclinical" AD in our population is relatively low based on the NIA-RI classification. Although many subjects had AD-like changes based on CERAD and Khachaturian guidelines, they exhibited no differences in mental performance, suggesting that the aging brain may be able to withstand such structural changes without meaningful impact on mental functioning.

Aged↗