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PubMed1989

Evaluation of a user-operated patient-side blood gas and chemistry monitor in children undergoing cardiac surgery.

A study was performed to evaluate a user-operated patient-side blood gas and chemistry monitor (GEM-STAT, Mallinckrodt Sensor Systems, Ann Arbor, MI) for the first time in a group of infants and children with congenital heart disease undergoing cardiac surgery. Paired blood samples from 18 patients were analyzed by the test instrument and by standard clinical laboratory instruments. One failure of the test instrument, malfunction of a cartridge, occurred during the evaluation. The integrated and external quality control functions gave readings within the manufacturer's tolerance. The differences between the measurements obtained using the GEM-STAT and the standard laboratory instruments for five of the six variables are summarized as follows (mean +/- SD, units of measure, number of samples): pH (-0.017 +/- 0.02, 132), PaCO2 (-1.90 +/- 3.3 mm Hg, 130), hematocrit (-1.3 +/- 2.3%, 129), potassium (-0.17 +/- 0.20 mmol, 112) and sodium (-2.0 +/- 3.3 mmol, 112). The mean difference in the measurements of PaO2 in the clinically important range defined by the upper quality control limit for oxygen tension of 172 mm Hg for the GEM-STAT is: (-0.20 +/- 7.26 mm Hg, 51). The mean difference between the measurements for PaO2s below the lowest quality control point (60 mm Hg) was (-2.3 +/- 5.5 mm Hg, 30). The values for all variables obtained from the GEM-STAT during the trial period, with the exception of the PaO2 less than 60 mm Hg, showed good correlation with the laboratory over the clinically useful range.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Chemical Analysis↗
PubMed2003

Intelligence in childhood epilepsy syndromes.

UNLABELLED: Intellectual deficits play a significant role in the psychosocial comorbidity of children with epilepsy. Early educational intervention is critical. OBJECTIVE: This study aims to determine the intellectual ability of children with common childhood epilepsy syndromes-generalised idiopathic epilepsy (GIE), generalised symptomatic epilepsy (GSE), temporal lobe epilepsy (TLE), frontal lobe epilepsy (FLE), central epilepsy (CE) and non-localised partial epilepsy (PE). METHODS: A prospective consecutive series of 169 children were recruited. Epilepsy syndrome was identified by clinical data, seizure semiology, interictal and ictal EEG in each child, using International League Against Epilepsy criteria. Each child had neuropsychology assessment using age-normed and validated instruments. After adjusting for important epilepsy variables, 95% confidence intervals were generated for mean full-scale intelligence quotient (FSIQ) using ANCOVA. RESULTS: Significant differences between epilepsy syndrome groups were found for age of onset (P<0.001), duration of active epilepsy (P=0.027), seizure frequency (P=0.037) and polytherapy (P=0.024). Analysing FSIQ, children with GIE, CE and TLE performed best, and did not differ statistically. Children with GSE had a statistically lower FSIQ than other syndrome groups except PE. FLE functioned significantly better than GSE, but did not differ statistically from other groups. CONCLUSIONS: In childhood epilepsy, delineation of the syndrome has important implications when considering intellectual potential. This information is invaluable in planning educational interventions and supporting the family.

Adolescent↗
PubMed1995

A computerized non-invasive method for the assessment of human facial volume.

The three-dimensional coordinates of 22 standardized soft-tissue facial landmarks were used in the definition of a three-dimensional model of the adult human face. The model allows the estimation of the volume of the face in toto and of its parts (upper, middle and lower thirds, nose). Landmark coordinates were collected in 80 healthy young adults (40 men and 40 women selected according to criteria of dentofacial normality) by infrared photogrammetry by an automated instrument, and facial volumes calculated. Sample variability was larger in women than in men; the nose and the upper third of face had the largest variability regardless of gender. On average, all volumes computed in men were significantly larger than the corresponding values computed in women. Also the lower-to-middle third face ratio was significantly higher in men than in women. The sexual dimorphism in human facial volume did not involve the different parts of the face to the same extent: a large part of male facial volume preponderance was explained by the lower third of face. The proposed facial model could adequately represent the human face in all those research and clinical fields where noninvasive surface measurements could be employed alone or in support of conventional radiographic data.

Adult↗
PubMedDate not supplied

A review of fatigue in people with HIV infection.

Fatigue is often cited by clinicians as a debilitating symptom suffered by the many who are infected with HIV. This article provides a review of HIV-related fatigue, including research on possible physiological causes such as anemia, CD4 count, impaired liver function, impaired thyroid function, and cortisol abnormalities. Psychological causes of fatigue, particularly depression, are reviewed as well. Measurement issues, such as the use of inappropriate tools, the problem of measuring the presence or absence of fatigue, and the use of tools developed for other groups of patients, are reviewed. The need for a comprehensive fatigue tool that is appropriate for people with HIV is discussed. Current treatment research, including thyroid replacement, hyperbaric oxygen, and dextroamphetamine, is presented. Finally, the implications for further research, including the need for qualitative studies to learn more about the phenomenon, develop an instrument to measure fatigue, and examine variables together to get a complete picture of this complex concept, are reviewed.

CD4 Lymphocyte Count↗
PubMed2003

The effects of movement, relaxation, and education on the stress levels of women with subclinical levels of bulimia.

The purpose of this study was to assess the impact of a multidisciplinary intervention program on the attitudes and symptoms associated with bulimia nervosa (BN). The Bulimia Test (BULIT) and subscales from the Eating Disorder Inventory-2 (EDI-2) associated with BN were administered to 373 females to determine eligibility for participation in the study. In order to qualify for the study, participants had to be female, not be anorexic, and meet one of four criteria indicating that they had some of the symptoms of BN. Following the screening, 12 females were randomly assigned to a control group (C, n=6) or an intervention group (I, n=6). The I group then participated in an 8-week multidisciplinary intervention program consisting of small group discussions, movement improvisation, and relaxation techniques. Dependent variables consisted of scores from standardized instruments for anxiety, self-esteem, and BN. A multivariate analysis of variance (MANOVA) on the difference score from post- to pretest was calculated for state and trait anxiety. That analysis indicated that compared to the C group, which showed no reduction in anxiety, the I group had a significant reduction in anxiety following the intervention program. No significant differences were found between groups for self-esteem or symptoms of BN. Conclusions were that anxiety levels were lowered in the I group; however, attitudes or behaviors associated with BN were not affected by the intervention.

Clinical Trial↗
PubMedDate not supplied

Clinical and psychological correlates of lumbar motion abnormalities in low back disorders.

BACKGROUND CONTEXT: Low back pain (LBP) and low back disorders (LBDs) identify a complex constellation of conditions that frustrate both diagnosis and therapy. Dynamic quantitative assessment and questionnaire instruments directed toward psychosocial and situational variables provide potentially powerful tools for determining functional pathology and potentially outcome. PURPOSE: Our goal was to independently assess clinical correlates of a trunk motion measurement device, the lumbar motion monitor (LMM). The reliability of the LMM as a clinical test was assessed by comparison with an independent medical examination and biobehavioral questionnaires. STUDY DESIGN/SETTING: There were three study components. A multispecialty physician panel that administered a structured physical examination contributed to a clinical correlation case series study. Standardized outcomes and risk identification questionnaires were administered to the case population. Finally, the LMM was administered in a customary fashion to the same population. PATIENT SAMPLE: Nineteen subjects were recruited on the basis of criteria that included symptoms of chronic recurrent low back pain. This was an employed and active, although impaired, population. Eighteen of the subjects were currently employed with limited lost work time, but chronic and recurrent pain was a common feature. OUTCOME MEASURES: Questionnaire outcome measures were both characterologic and situation based. In addition to providing diagnoses, the physician panel was also asked to offer certain qualitative assessments, such as rehabilitative potential and functional level pertinent to activities of daily living. The impact of LMM measures on physician decision making was also assessed. Trunk angular measurements were used to assess function of patients with chronic low back disorders. METHODS: Kinematic performance on the LMM was expressed as three probability scores. These were the likelihood of abnormality, the "sincerity of effort" (exacerbation or aggravation of impairment), and the likelihood of structural anatomic disease. These variables were examined against established self-report measures of pain and disability. RESULTS: The LMM and physician panels were in agreement on the presence or absence of abnormality. LMM findings tended to be more consistent with clinical history than the clinical examination. The LMM results were also generally consistent with the self-reported measures of pain and disability: a high likelihood of structural disease was associated with depression, somatization, poor health perception and diminished vitality. CONCLUSIONS: The LMM appears to be a useful assessment tool for gauging the presence of LBP and LBD. It was accurate in detecting abnormality when abnormality was determined by clinical history and physician diagnosis. The LMM's differentiation of mechanical low back disease (nonanatomically specific disorders) from structurally specific low back disease was not consistent with a parallel clinical differentiation. Larger trials in a prospective format and studies on a chronically disabled population seem warranted. In an impaired but less disabled population, elevated pain and somatization did not appear to weaken the effort during testing.

Adult↗
PubMed2003

Rectal function following brachytherapy with or without supplemental external beam radiation: results of two prospective randomized trials.

PURPOSE: To evaluate the effect of isotope and supplemental external beam radiation therapy (XRT) on brachytherapy-related rectal morbidity, using prospective, patient-administered quality of life (QOL) assessments. METHODS AND MATERIALS: Two hundred thirteen consecutive patients (median follow-up 22 months) were implanted on 2 prospective randomized brachytherapy trials evaluating the effect of isotope for low-risk patients and different doses of supplemental XRT for patients with higher risk features. Treatment-related rectal morbidity was evaluated by modified Radiation Therapy Oncology Group (RTOG) criteria and the multifactorial Rectal Function Assessment Score (R-FAS). Clinical, treatment and dosimetric parameters evaluated included patient age, diabetes, hypertension, tobacco consumption, clinical stage, prostate ultrasound volume, elapsed time since implant, hormonal manipulation, supplemental XRT, isotope, treatment planning volume, and values of the minimum dose received by 90% of the prostate gland (D90), the percent prostate volume receiving 100%, 150%, and 200% of the minimum peripheral dose (V(100/150/200)), rectal implant doses (V(75/100/125/150) and D(5/10/25/50)) and rectal XRT doses (D(5/10/25/50/75)). RESULTS: Using the RTOG instrument, rectal morbidity peaked at 1 month. The pre- and most recent postimplant median RTOG scores were 0 and 0, respectively. The pre- and postimplant R-FAS scores were 2.41 and 3.83, respectively. With time, the rectal scores for both instruments improved and approached baseline. In multivariate analysis, only the rectal dosimetry variable D5 predicted for bowel function when using the R-FAS instrument. No clinical, treatment, or dosimetric parameters predicted for bowel function when using the RTOG survey. No patient required surgical intervention for rectal complications. CONCLUSIONS: The multifactorial R-FAS elucidated fine gradations in bowel function of a severity less than RTOG Grade 3 morbidity. Of multiple clinical, treatment, and dosimetric parameters evaluated, only the minimum dose received by 5% of the rectum (D5) correlated with rectal dysfunction via the R-FAS instrument, while none of the evaluated parameters predicted for bowel dysfunction using the RTOG survey. Following permanent prostate brachytherapy, the ability to discern subtle changes in rectal function is dependent on the sensitivity of the survey instrument.

Aged↗
PubMed1999

Sample size calculations in studies using the EuroQol 5D.

Health-related quality of life (HRQoL) instruments are increasingly used as outcome variables in clinical trials, leading to a requirement for sample size calculations based on these variables. This paper aims to provide a guide to sample size calculations for use with the EuroQol-5D. The paper focuses on sample sizes required for comparative studies, and uses scores from two reference groups of general population and critically ill patients to determine sample sizes using the three parts of the EQ-5D (descriptive system, visual analogue scale (VAS), and EQ-5D index). The effect on sample sizes of different methods of categorising the three variables are compared, and comparisons are also made between sample sizes using parametric and non-parametric methods. Sample sizes required when the EQ-5D descriptive system is used as a binary variable (problems/no problems) are higher than or equal to those required when each dimension is categorised in three levels of severity (no problems, moderate problems, extreme problems). The use of three categories is appropriate in ill populations, though in more healthy populations two categories should be used. Due to the slight skewness of VAS data, and the equality of results using parametric and non-parametric methods, sample size calculations using the VAS should be based on a parametric approach. Sample sizes were considerably higher for the EQ-5D index when predefined intervals, as opposed to a score frequency based categorisation, were used with the general population reference group. Using the EQ-5D index in ill populations, it is recommended that sample size calculations are based on parametric methods, whilst in healthier populations non-parametric methods should be used.

Critical Illness↗
PubMed1997

Measuring psychosocial work quality and health: development of health care measures of measurement.

Demands on workload and work efficiency have increased because of ongoing global changes in health care organizations. Assessing and evaluating effects of changes on organizational and individual well-being require valid and reliable methods. Questionnaires from 3 large health care studies were used to develop instruments for work quality and health. Variable fields of work quality, health and well-being, and modifying factors were factor analyzed with replicated structures in new samples, including 6 factors of work quality, 5 health factors, and 2 modifying factors. All except 2 factors had high internal consistency (Cronbach's alpha = .69-.84) and low factor intercorrelations within areas. Social climate (but not individual resources) had, according to our model, a modifying effect on the work-health interaction.

Adult↗
PubMed2003

Oral anticoagulant monitoring by laboratory or near-patient testing: what a clinician should be aware of.

Prothrombin time (PT) is the primary laboratory test for monitoring oral anticoagulant treatment but is influenced by preanalytical conditions and analytical variables, that is, thromboplastin reagents and instrumentation. Standardization and normalization of test results is mandatory. PT results should be transformed to International Normalized Ratio (INR) by calibration of the reagent/instrument system with International Reference standards according to World Health Organization guidelines. However, there is still uncertainty in the INR that is caused in part by calibration errors and in part by interaction between the PT reagent and various factors in the patient's specimen. These problems are highlighted in INR measurements performed with whole blood coagulation monitors. Each center should maintain an appropriate scheme of internal and external quality control for the laboratory INR measurement as well as the individual point-of-care coagulation monitors used by the center and patients for self-testing.

Administration, Oral↗
PubMedDate not supplied

Predictors of self-care in persons with heart failure.

OBJECTIVE: The objective of this study was to test a model of individual patient characteristics, covering symptom severity, comorbidity, social support, education, age, socioeconomic status, and gender, derived from Connelly's Model of Self-Care in Chronic Illness as predictors of self-care in heart failure. DESIGN: This was a nonexperimental correlational study. SETTING: The study took place in 6 hospitals in southern California. PATIENTS: The study included 209 patients diagnosed with heart failure by their physicians. The typical study participant was age 73 years, Class III, married, grade-school educated, and earning an income of less than $20,000 per year. The genders were almost equally represented. OUTCOME MEASURE: Self-care was measured by the Evaluating the Change subscale of the Self-Management of Heart Failure Instrument. RESULTS: The model of 7 variables, analyzed by using multiple regression analysis, explained 10.3% of the variance in self-care. Only 2 of the variables were significant predictors of self-care: education (P =.009) and symptom severity (P =.046); 89.7% of the variance remained unexplained. CONCLUSIONS: Persons with higher education and those who are symptomatic may be more likely to engage in self-care than those who are poorly educated or asymptomatic. Further research is needed to confirm these Results and identify other predictors of self-care.

Adult↗
PubMed1994

Teachers' attitudes toward testing practices.

The purpose of this research was to investigate how teachers' attitudes toward testing practices affect the way teachers prepare and administer standardized tests. Classroom teachers (N = 186) from Georgia took the testing practices instrument developed to measure the three variables (behavior, attitude, and pressure) examined in this study. Attitudes were negatively correlated with behavior; teachers who felt that the testing practices were dishonest were less likely to engage in them. Pressure to increase standardized test scores was positively correlated with behavior; the greater the perceived pressure (subjective norms) to increase test scores, the greater the likelihood that teachers had engaged in more test preparation activities. The data also suggest that the amount of test preparation was greater in the lower grades than in the upper grades and that teachers in schools with more low-socioeconomic-status (SES) students tended to engage in more test preparation activities than their colleagues in higher SES schools.

Attitude↗
PubMed1994

Verbal learning patterns in moderate and severe traumatic brain injury.

Previous studies that have examined performances on the California Verbal Learning Test (CVLT) among individuals with traumatic brain injury (TBI) have found differing levels of performance. Differential patterns of performance, however, have only been inferred. The present investigation sought to determine empirically if differential patterns of performance could be discerned in a TBI sample of 65 subjects with CVLT variables. The CVLT variables were selected based on the instrument's factor structure. Cluster analysis yielded four distinct subtypes of brain-injured individuals. The Active subtype demonstrated impaired unassisted retrieval, but used active encoding strategies and showed relatively intact ability to store novel information. The Disorganized subtype demonstrated an inconsistent, haphazard learning style along with deficits in encoding. The Passive subtype was marked by an overreliance on a serial clustering strategy as well as impaired encoding and/or consolidation. The Deficient subtype was the most impaired of all groups, exhibiting a slowed rate of acquisition, passive learning style, and significant impairment in encoding. Implications for rehabilitation are discussed.

Adolescent↗
PubMedDate not supplied

Mayo's Older Americans Normative Studies: Age- and IQ-Adjusted Norms for the Auditory Verbal Learning Test and the Visual Spatial Learning Test.

Although normative data sets for standardized neuropsychometric instruments frequently feature adjustments for subject variables, there are reasons to believe that improvements in interpretive accuracy that result from such adjustments are less than optimal. In particular, years of education may be less closely associated with test performances than is overall intellectual functioning. In this last of four reanalyses of results from the Mayo Clinic's Older Americans Normative Studies (MOANS) databases, age-adjusted scores for the Rey Auditory Verbal Learning Test and the Visual Spatial Learning Test were found to be more strongly related to Mayo age-adjusted WAIS-R Full Scale IQ scores (rs=.150 to .395) than to education (rs=.060 to .236) for healthy older examinees between 56 and 99 years of age. Although AVLT-FSIQ correlations were greatest at moderate levels of intelligence, VSLT-FSIQ correlations consistently increased in strength as intelligence increased (cf. Dodrill, 19971999). Based on these results, we present tables of age- and IQ-adjusted percentile equivalents of Mayo age-adjusted AVLT index scores and MOANS age-adjusted AVLT and VSLT scaled scores for ten age ranges and either seven (AVLT) or five (VSLT) IQ ranges.

Acoustic Stimulation↗
PubMedDate not supplied

Mayo's Older Americans Normative Studies: Age- and IQ-Adjusted Norms for the Wechsler Memory Scale--Revised.

Normative data sets for standardized neuropsychometric instruments often include adjustments for subject variables. There are reasons to believe, however, that improvements in interpretive accuracy that result from such adjustments are less than optimal. In particular, "years of formal education" may be less closely related to test performances than is general intellectual functioning. In this third of four reanalyses of results from the Mayo Clinic's Older Americans Normative Studies (MOANS) databases, age-adjusted index and scaled scores for the Wechsler Memory Scale-Revised were found to be more strongly associated with Mayo age-adjusted WAIS-R Full Scale IQ scores (rs=.271 to .631) than with education (rs=.089 to .310) for healthy older examinees between 56 and 99 years of age. These associations were strongest for Attention/Concentration and General Memory Index scores and, in general, for individuals with average intelligence (cf. Dodrill, 19971999). Tables of age- and IQ-adjusted percentile equivalents of Mayo age-adjusted WMS-R index scores and MOANS age-adjusted WMS-R subtest scaled scores are presented for eleven age ranges and seven IQ ranges.

Age Factors↗
PubMedDate not supplied

Mayo's Older Americans Normative Studies: Age- and IQ-Adjusted Norms for the Trail-Making Test, the Stroop Test, and MAE Controlled Oral Word Association Test.

Although normative data sets for standardized neuropsychometric instruments often include adjustments for subject variables, there are reasons to believe that improvements in interpretive accuracy that result from such adjustments are less than optimal. In particular, years of formal education may be less closely related to test performances than is general intellectual functioning. In this second of four reanalyses of results from the Mayo Clinic's Older Americans Normative Studies (MOANS) databases, age-adjusted scores for the Trail-Making Test, the Stroop Color-Word Test, and the MAE Controlled Oral Word Associations Test were found to be more strongly associated with Mayo age-adjusted WAIS-R Full Scale IQ scores (rs=.368 to .495) than with education (rs=.174 to .367) for healthy older examinees between 56 and 99 years of age. For the TMT and the COWAT, but not the Stroop, these associations became stronger as IQ increased (cf. Dodrill, 1997, 1999). Tables of age- and IQ-adjusted percentile equivalents of MOANS age-adjusted TMT, Stroop, and COWAT scores are presented for eleven age ranges and seven IQ ranges.

Age Factors↗
PubMed1991

Disinfection practices for endoscopes and other semicritical items.

OBJECTIVE: To determine the disinfection practices employed by North Carolina hospitals for endoscopes and other semicritical patient care items and to discuss minimally acceptable disinfection procedures for these items. DESIGN: A survey questionnaire was mailed to all North Carolina hospitals to identify their disinfection practices, and a literature review was conducted to ascertain studies that evaluated disinfection techniques for certain semicritical items. PARTICIPANTS: Questionnaires were returned by 107 of 167 (64%) North Carolina acute-care hospitals. RESULTS: Most hospitals (91%) used a glutaraldehyde-based disinfectant (59%, 2% glutaraldehyde; 29%, 0.13% glutaraldehyde-0.44% phenol-0.08% phenate; 3%, either); half (51%) of the hospitals immersed the endoscope into disinfectant for greater than or equal to 20 minutes, but 44% immersed for less than or equal to 10 minutes; nearly all hospitals (97%) disinfected endoscopes at room temperature. Hospitals rinsed the endoscope with sterile water (16%), tap water (54%), tap water followed by alcohol rinse (27%), or other (2%); 58% of the hospitals treated endoscopes from patients infected with human immunodeficiency virus (HIV), hepatitis B virus (HBV), or Mycobacterium tuberculosis differently (81%, ethylene oxide [ETO] sterilization; 10%, increased exposure time; 10%, other). Twenty percent of the hospitals used an automated washer for processing endoscopic instruments. Rigid endoscopes (e.g., arthroscopes, laparoscopes) were primarily high-level disinfected (57%), ETO sterilized (17%), or either (13%). The disinfection strategies for other semi-critical items (e.g., applanation tonometers, cryosurgical instruments, and diaphragm fitting rings) were highly variable for the responding hospitals. CONCLUSIONS: This survey indicated the presence of a wide variety of practices for handling semicritical patient care items, many of which are inconsistent with current recommendations. To help establish minimally acceptable disinfection procedures for some patient care instruments (e.g., arthroscopes, laparoscopes, tonometers), the scientific literature was reviewed and recommendations were made.

Disinfection↗
PubMed2005

Evaluation of arterial endothelial function using transit times of artificially induced pulses.

Impairment of arterial endothelial function is an early event in atherosclerosis and correlates with the major risk factors for cardiovascular disease. The most widely employed non-invasive measure of endothelial function involves brachial artery (BA) diameter measurement using ultrasound imaging before and after several minutes of blood flow occlusion. The change in arterial diameter is a measure of flow-mediated vasorelaxation (FMVR). The high between-laboratory variability of results and cost of instrumentation render this technique unsuitable for routine clinical use. We induce artificial pulses at the superficial radial artery using a linear actuator. An ultrasonic Doppler stethoscope detects these pulses 10-30 cm proximal to the point of pulse induction. The delay between pulse application and detection provides the pulse transit time (PTT). By measuring PTT before and after 5 min of BA occlusion and ensuing reactive hyperemia, FMVR may be measured based on the changes in PTT caused by changes in vessel caliber, smooth muscle tone and wall thickness. We (1) validate the sensitivity of this technique to arterial wall tone using sublingual nitroglycerin and (2) compare measurements of endothelial function to ultrasound BA diameter measurements in 12 human subjects. The PTT-based method is verified to measure arterial wall tone and is shown to provide 37% greater sensitivity (p < 0.05) to FMVR than BA diameter measurements. By measuring the change in pulse transit time before and after endothelial stimulus, a sensitive, reproducible and convenient measure of endothelial function may be obtained at a low cost.

Blood Flow Velocity↗