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PubMed1990

Quantification of biomedical findings of chronic pain patients: development of an index of pathology.

Difficulties in assessing and quantifying the biomedical signs and symptoms that may be related to patients' reports of pain are well recognized. Although there appears to be some consensus among physicians as to the potential utility of examination and diagnostic tests frequently used to evaluate chronic pain patients, little attention has been paid to the reliability of interpreting the results of these procedures. Moreover, the integration of biomedical findings to form a general index of pathology associated with chronic pain has been a difficult problem to solve because not all biomedical procedures used to evaluate pain patients are necessarily relevant or indicated for a specific patient. Two studies are presented that were designed to evaluate the reliability of 23 biomedical procedures commonly used to evaluate chronic pain patients and to determine if findings on these procedures can effectively be combined to form a reliable index of physical pathology. The results of study 1 suggest that 17 of the 23 procedures can be applied in clinical setting with acceptable levels of reliability. Study 2 provides evidence that an innovative weighted scoring approach, based on current medical consensus, can be used to produce a reliable, general index of pathology that is independent of the number of procedures used to evaluate patients. The utility of this quantification approach to biomedical findings for clinical and research purposes is discussed.

Chronic Disease↗
PubMed1982

Lack of association between preference for and dependence on ethanol.

Tests were performed on 60 HS mice to determine preference for ethanol before and after a period of forced ethanol ingestion via a liquid diet treatment. Seizure scores measured 4, 5 and 6 h after the end of the liquid diet treatment showed that moderate degrees of physical dependence had developed. Statistical analyses revealed a significant sex difference only for the amount of ethanol consumed during the liquid diet treatment, with females drinking more than males (on a g/kg basis). Correlation analyses indicated that preference for ethanol was not related to seizure severity or to amount consumed during the liquid diet treatment. A significant drop in preference after ethanol withdrawal was observed when pre- and post-withdrawal preference ratios were compared. These findings are discussed in the context of the usefulness of preference for ethanol as a predictor of alcoholism.

Alcoholism↗
PubMed2006

Use and costs of nonrecommended tests during routine preventive health exams.

BACKGROUND: Routine office visits for preventive health exams (PHEs) are designed to identify asymptomatic diseases at early treatable stages and influence healthy behaviors. Investigation included how often diagnostic tests and procedures were performed for which evidence and guidelines recommend against in asymptomatic individuals during routine PHEs, and the costs associated with the tests and procedures. METHODS: In 2005, a cross-sectional study of office-based interventions was conducted, using National Ambulatory Medical Care Survey (NAMCS) data from 1997 to 2002. Recommendations from the United States Preventive Services Task Force (USPSTF) were used as a measure of appropriateness of diagnostic interventions during the PHE. Laboratory tests and procedures not recommended (D ranking) included urinalysis (UAs); interventions not recommended included electrocardiograms (EKGs) and x-rays. RESULTS: The frequency of ordering any of the three diagnostic interventions ranged from 5% to 37%, and at least one of the interventions was ordered 43% of the time. Annual direct costs for the three interventions range from $47 million to $194 million. CONCLUSIONS: Less use of unwarranted interventions will likely eliminate waste and improve the overall quality of health care in the United States.

Adult↗
PubMed2006

Lecture versus standardized patient interaction in the surgical clerkship: a randomized prospective cross-over study.

BACKGROUND: Medical schools increasingly are incorporating the standardized patient (SP) interaction as a teaching and testing modality to prepare students for United States Medical Licensing Examination Step 2 Clinical Skills. Although SP interactions provide a safe environment in which to practice clinical skills, little is known about medical students' perceptions of the instructional SP interaction in comparison with the classic didactic lecture. We hypothesized that students would enjoy and value an instructional SP interaction more than a didactic lecture, and that this perception would be enhanced if the lecture immediately preceded the instructional SP interaction. METHODS: Students on the junior surgery clerkship from January to December 2004 were randomized into 2 groups. Group A (n = 71) received an hour-long didactic lecture about peripheral vascular disease followed by a 20-minute instructional SP interaction in which the SP portrayed a patient with lower-extremity claudication. Group B (n = 72) received the SP interaction first, followed by the lecture. All students received an identical quiz about peripheral vascular disease after the second educational encounter, whether the SP interaction or the lecture. Student perceptions were surveyed by written questionnaire before and after the session by using a 5-point Likert scale, with 5 being the most favorable rating. Data (perceptions, performances on the quiz and the SP interaction, clerkship grades) were compared using the Student t test or the Mann-Whitney rank sums test. RESULTS: Although all students on average enjoyed and valued the lecture more than the SP interaction (P <.001), group A students enjoyed the SP interaction more than group B (3.3 +/- .9 vs. 2.8 +/- 1.0, P = .008), and they perceived the SP interaction as having more value to their overall education (3.3 +/- 1.0 vs. 2.8 +/- 1.0, P = .004). Group A students performed statistically better on the physical examination (66% +/- 19% vs. 40% +/- 16%, P <.001) and communication portions (90% +/- 11% vs. 79% +/- 12%, P <.001) of the SP checklist than group B, but not on the history portion. Student confidence in their own history and physical examination skills increased similarly for both groups. CONCLUSIONS: The classic lecture format not only is enjoyed and valued as a learning tool more by our surgical clerkship students than the instructional SP interaction, but having a lecture just before an SP interaction increased perceived enjoyment and value of the SP interaction and enhanced performance on the SP checklist. These data suggest that educators can improve student perceptions and attitudes surrounding the instructional SP interaction by using strategically timed lectures.

Clinical Clerkship↗
PubMed2006

Resistance training improves muscle function and body composition in patients with hyperthyroidism.

OBJECTIVE: To evaluate the effect of resistance training on skeletal muscle performance and body composition in patients with medically treated hyperthyroidism. DESIGN: Nonrandomized controlled trial. SETTING: Large public tertiary hospital. PARTICIPANTS: Sixteen sedentary patients with recent clinical diagnosis and laboratory confirmation of hyperthyroidism (7 men, 9 women; age, 38+/-11 y; weight, 58.4+/-2.6 kg; height, 1.6+/-0.3m) were assigned to the control group (medical therapy; n=9) or training group (medical therapy associated with resistance training; n=7). An age- and sex-matched healthy group served as controls (3 men, 5 women; age, 40+/-3 y; weight, 68.4+/-4.3 kg; height, 1.6+/-0.3m). INTERVENTION: Resistance training twice a week for 16 weeks. MAIN OUTCOME MEASURES: Peak muscular strength (by dynamometry and 1 repetition maximum method) and endurance (30% of peak force) for 7 movements and anthropometric measurements. RESULTS: The hyperthyroid patients as a group had lower baseline overall strength values when compared with healthy subjects (200.3+/-16.0 kg vs 274.9+/-21.8 kg, respectively; P=.006). Overall absolute increases in strength (49 kg vs 91 kg, P<.05) and endurance (78.5x10(2)kg/s vs 176.9x10(2)kg/s, P<.05) were higher in the training group compared with the control group. Body weight increased in both groups, but the sum of muscular circumference increased only in the training group (training group, 92.6+/-3.3 cm vs 97.1+/-3.8 cm; control group, 94.6+/-2.2 cm vs 94.4+/-2.1cm; P<.05), with no change in the sum of skinfolds. CONCLUSIONS: Resistance training accelerates the recovery of skeletal muscle function and promotes weight gain based on muscle mass improvement in patients with medically treated hyperthyroidism.

Adult↗
PubMed2005

Interfacial rheology of adsorbed layers with surface reaction: on the origin of the dilatational surface viscosity.

A theoretical study of the phenomena, occurring in an adsorbed layer, subject to small dilatational perturbations was carried out. Two main processes, provoked by the perturbations (surface reaction and surfactant transport onto the surface) were considered. The reaction was described by means of the reaction coordinate. The derived general rheological equation for insoluble surfactants, gave as limiting cases Voight and Maxwell type equations for fast and slow reactions, respectively. Expressions for all characteristics of the process (surface elasticity, reaction elasticity, reaction relaxation time and dilatational surface viscosity) were obtained. The obtained generalized rheological equation for reactions involving soluble surfactants is a dynamic analog of Gibbs adsorption isotherms for a multi-component system with surface reaction, since similarly to Gibbs equation it relates the surface stress only to surface variables. It gives as limiting cases generalized forms for soluble surfactants of Voight and Maxwell equations. All new rheological equations were analyzed for deformations with constant rate and periodic oscillations and they were applied to three simple surface reactions (monomolecular with one product, dimerization and association). The mass transfer was analyzed initially in the absence of surface reaction. In this system the surface stress is purely elastic, but it was shown that if the adsorption perturbation is small, regardless of the type of surface perturbation and the mechanism of adsorption, the process of mass transport always obeys a Maxwell type rheological equation. For all considered processes surface viscosities were defined, but they were called "apparent", because they stem from diffusion, rather than from interaction between the surfactant molecules and they depend not only on surface parameters, but also on the geometry of the system. The often used in the literature correlations between the lifetime of emulsions and foams and the imaginary elasticity were analyzed. It was shown that this approach lacks serious scientific foundations and could lead to erroneous conclusions. Finally, the problem for the coupling of the surfactant diffusion with the chemical reaction was analyzed and it was demonstrated on a simple example how it could be tackled.

Adsorption↗
PubMed2006

The relationship between two different mechanical cost functions and muscle oxygen consumption.

Inverse-dynamic models often use cost functions to solve the load-sharing problem. Although it is often assumed that energy is minimised, most cost functions are based on mechanically related measures like muscle force or stress. The aim of this study was to analyse the relationships of two cost functions with experimentally determined data on muscle energy consumption. Four subjects performed isometric contractions generating combinations of elbow flexion/extension and pro/supination moments. Muscle oxygen consumption (VO2) of the m. biceps breve, m. biceps longum, m. brachioradialis and m. triceps laterale was measured with near infrared spectroscopy. Both cost functions were implemented into an existing inverse-dynamic shoulder and elbow model and the individual cost values per muscle were calculated, normalised and subsequently compared to experimental VO2 values. The minimum stress cost function led to a good correspondence between VO2 and cost for the m. triceps laterale but for the flexor muscles cost was significantly lower. A newly proposed energy-related cost function showed, however, a far better correspondence. The inclusion of a linear term and muscle mass in the new criterion led model results to correspond better to experimental results. The energy-related cost function appeared to be a better measure for muscle energy consumption than the stress cost function and led to more realistic predictions of muscle activation.

Adult↗
PubMed2005

A quantitative model for flow-induced bioluminescence in dinoflagellates.

A model is presented for the flash response of bioluminescent dinoflagellates stimulated by fluid shear. The model is based on the idea that the response of an individual cell to stimulation is inherently probabilistic, and can be modeled as a Poisson process over short time scales. A new cell parameter, the cell anxiety, is introduced to parameterize the probability of flashing. The statistical model is incorporated into a description of fully developed fluid flow in pipes and a cylindrical Couette chamber, and found to compare favorably with previously published data from experiments.

Animals↗
PubMed2004

The effects of acute and chronic restraint stress on activation of ERK in the rostral ventromedial medulla and locus coeruleus.

Extracellular signal-regulated kinase (ERK) is a key molecule in numerous cellular and physiological processes in the CNS. Exposure to stressors causes substantial effects on the perception and response to pain. The rostral ventromedial medulla (RVM) and the locus coeruleus (LC) play crucial roles in descending pain modulation system. In the present study, the activation of ERK in the RVM and the LC in rats following acute and chronic restraint stress was examined in order to characterize the mechanisms underlying stress induced analgesic and hyperalgesic responses. Rats were stressed by restraint 6h daily for 3 weeks. The acute and chronic restraint stresses produced analgesic and hyperalgesic reactions, respectively, to thermal stimuli applied to the tail. The phospho-ERK-immunoreactive (p-ERK-IR) neurons were observed in the nucleus raphe magnus (NRM), nucleus reticularis gigantocellularis pars alpha (GiA) and LC. In the RVM, the number of p-ERK-IR neurons per section in the 3-week restraint rats (14.3+/-1.2) was significantly higher than that in the control rats (8.9+/-0.7) [P<0.01]. About 75% of p-ERK-IR neurons in the RVM in the 3-week restraint rats were serotonergic neurons. Protein levels of tryptophan hydroxylase were significantly increased in the RVM region in the 3-week restraint rats. On the other hand, the chronic restraint stress significantly decreased p-ERK-IR in the LC [P<0.05]. These findings suggest that chronic restraint stress-induced activation of ERK in the RVM and the suppression in the LC may be involved in the modulation of the pain threshold by chronic stress.

Animals↗
PubMed1998

The effect of traffic patterns in the OR on surgical site infections.

Perioperative nurses are situated uniquely to promote good traffic control practices in the OR. This study was conducted to explore the effect of traffic patterns, specifically the number of people in the OR, on the incidence of surgical site infections (SSIs). Researchers analyzed 2,864 clean surgical procedures performed in 1995 in an academic medical center. Duration of surgery and American Society of Anesthesiologists' physical assessment score were statistically significant risk factors for SSIs. A rising trend in SSIs was observed as the number of people in the OR increased; however, it was not statistically significant. Risk factors for SSIs must be better understood to develop more effective prevention programs.

Air Microbiology↗
PubMed2000

Washington State's model of physician leadership in cardiac outcomes reporting.

BACKGROUND: In 1993, the cardiac surgery community in Washington State opposed an effort by the state Health Care Authority (HCA) to identify "centers of excellence" for selective contracting of coronary artery bypass grafting (CABG) procedures, and proposed an alternate model that would create a statewide cardiac outcomes registry under physician governance to be used by all institutions for internal quality improvement activities. METHODS: A prospective pilot data collection effort, which examined preoperative and postoperative patient-reported health status, served as the basis for evaluating the capacity of a physician-led organization to develop a collaborative atmosphere and facilitate universal hospital participation. RESULTS: A surgical steering group met on a regular basis and reached consensus on governance issues, protocols for standardized data collection, and policies regarding data dissemination. All 14 centers that performed bypass surgery in the state participated. Patients who were surveyed reported statistically significant improvements in physical, emotional, and anginal-specific health status after bypass surgery. Baseline patient characteristics and longitudinal outcomes were compared across institutions. CONCLUSIONS: Based on the feasibility of this collaborative outcomes reporting program, the HCA revised its policy regarding selective contracting and has helped to support an ongoing physician-led and -governed cardiac outcomes reporting system that is particularly notable for the subsequent integration of both CABG surgery and catheterization-based procedures into one standardized registry.

Aged↗
PubMed2001

Anxiety sensitivity and major depression: examination of affective state dependence.

An emerging body of research suggests that anxiety sensitivity (AS), and particularly a facet of AS labelled fear of cognitive dyscontrol, is elevated in depressed individuals and is associated with severity of depressed mood. The current prospective study extended previous work by investigating the extent of affective state dependency in the AS-depression relationship in 51 patients who had major depressive episode (MDE) at baseline assessment (Time 1) and did not have MDE 1 year later at follow-up (Time 2). Despite considerable reduction in severity of depressed mood, scores on the Anxiety Sensitivity Index (M=27) remained elevated. Hierarchical regression analysis indicated that, after controlling for both Time 1 and Time 2 depression severity, Time 1 AS continued to predict residual Time 2 AS and increased prediction of variance from approximately 25% to 50%. Time 1 fear of cognitive dyscontrol AS continued to significantly predict Time 2 fear of cognitive dyscontrol AS when Time 2 fear of physical symptoms AS was statistically controlled. A subsample of recovered patients who displayed only minimal depression symptoms was compared to a matched sample of community controls. While the two groups did not significantly differ on level of depressed mood, the formerly depressed patients had significantly higher levels of AS. Implications for a proposed "depression sensitivity" are discussed.

Adult↗