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Arnaud Perrier

Publications and source records attributed to Arnaud Perrier.

At least 19 recordsLinked to original sources
PubMed2006

Should pulmonary embolism be suspected in exacerbation of chronic obstructive pulmonary disease?

BACKGROUND: The cause of acute exacerbation of chronic obstructive pulmonary disease (COPD) is often difficult to determine. Pulmonary embolism may be a trigger of acute dyspnoea in patients with COPD. AIM: To determine the prevalence of pulmonary embolism in patients with acute exacerbation of COPD. METHODS: 123 consecutive patients admitted to the emergency departments of two academic teaching hospitals for acute exacerbation of moderate to very severe COPD were included. Pulmonary embolism was investigated in all patients (whether or not clinically suspected) following a standardised algorithm based on d-dimer testing, lower-limb venous ultrasonography and multidetector helical computed tomography scan. RESULTS: Pulmonary embolism was ruled out by a d-dimer value <500 microg/l in 28 (23%) patients and a by negative chest computed tomography scan in 91 (74%). Computed tomography scan showed pulmonary embolism in four patients (3.3%, 95% confidence interval (CI), 1.2% to 8%), including three lobar and one sub-segmental embolisms. The prevalence of pulmonary embolism was 6.2% (n = 3; 95% CI, 2.3% to 16.9%) in the 48 patients who had a clinical suspicion of pulmonary embolism and 1.3% (n = 1; 95% CI, 0.3% to 7.1%) in those not suspected. In two cases with positive computed tomography scan, the venous ultrasonography also showed a proximal deep-vein thrombosis. No other patient was diagnosed with venous thrombosis. CONCLUSIONS: The prevalence of unsuspected pulmonary embolism is very low in patients admitted in the emergency department for an acute exacerbation of their COPD. These results argue against a systematic examination for pulmonary embolism in this population.

Aged↗
PubMed2006

Tutor training, evaluation criteria and teaching environment influence students' ratings of tutor feedback in problem-based learning.

AIM: In a problem-based learning (PBL) curriculum, tutor's feedback skills are important. However, evaluation studies often show that students rate many tutors as ineffective in providing feedback. We explored whether this is related: (a) to tutors' skills, and hence a teaching intervention might improve their performance; (b) to the formulation of the evaluation item, hence a more specific wording might help students better recognize a feedback when received; (c) to PBL teaching environment, and hence the tutors' teaching unit might influence students' ratings. METHODS: Students rated 126 tutors of 13 one-month teaching units over three consecutive years on their ability of providing feedback. We assessed how (a) a teaching intervention given between years 1 and 2, (b) a rewording of the evaluation item which took place in year 3, and (c) the tutors' teaching unit, influenced students' ratings. RESULTS: The ratings of tutors considered as effective by students at year 1 improved after the teaching intervention, while those of unsatisfactory tutors did not progress. However the ratings of the latter increased after reformulation of the evaluation item. This increase varied across teaching units. DISCUSSION: Students' ratings of tutors' ability to give feedback seem to vary in function of the tutors' training, of the formulation of the evaluation item, and of the tutors' teaching environment. These variables should be considered for setting up effective strategies in faculty development.

Analysis of Variance↗
PubMed2006

Prevalence and determinants of physician bedside rationing: data from Europe.

BACKGROUND: Bedside rationing by physicians is controversial. The debate, however, is clouded by lack of information regarding the extent and character of bedside rationing. DESIGN, SETTING, AND PARTICIPANTS: We developed a survey instrument to examine the frequency, criteria, and strategies used for bedside rationing. Content validity was assessed through expert assessment and scales were tested for internal consistency. The questionnaire was translated and administered to General Internists in Norway, Switzerland, Italy, and the United Kingdom. Logistic regression was used to identify the variables associated with reported rationing. RESULTS: Survey respondents (N=656, response rate 43%) ranged in age from 28 to 82, and averaged 25 years in practice. Most respondents (82.3%) showed some degree of agreement with rationing, and 56.3% reported that they did ration interventions. The most frequently mentioned criteria for rationing were a small expected benefit (82.3%), low chances of success (79.8%), an intervention intended to prolong life when quality of life is low (70.6%), and a patient over 85 years of age (70%). The frequency of rationing by clinicians was positively correlated with perceived scarcity of resources (odds ratio [OR]=1.11, 95% confidence interval [CI] 1.06 to 1.16), perceived pressure to ration (OR=2.14, 95% CI 1.52 to 3.01), and agreement with rationing (OR=1.13, 95% CI 1.05 to 1.23). CONCLUSION: Bedside rationing is prevalent in all surveyed European countries and varies with physician attitudes and resource availability. The prevalence of physician bedside rationing, which presents physicians with difficult moral dilemmas, highlights the importance of discussions regarding how to ration care in the most ethically justifiable manner.

Adult↗
PubMed2006

Drug-induced long QT syndrome in injection drug users receiving methadone: high frequency in hospitalized patients and risk factors.

BACKGROUND: Drug-induced long QT syndrome is a serious adverse drug reaction. Methadone prolongs the QT interval in vitro in a dose-dependent manner. In the inpatient setting, the frequency of QT interval prolongation with methadone treatment, its dose dependence, and the importance of cofactors such as drug-drug interactions remain unknown. METHODS: We performed a systematic, retrospective study comparing active or former intravenous drug users receiving methadone and those not receiving methadone among all patients hospitalized over a 5-year period in a tertiary care hospital. A total of 167 patients receiving methadone fulfilled the inclusion criteria and were compared with a control group of 80 injection drug users not receiving methadone. In addition to methadone dose, 15 demographic, biological, and pharmacological variables were considered as potential risk factors for QT prolongation. RESULTS: Among 167 methadone maintenance patients, the prevalence of QTc prolongation to 0.50 second((1/2)) or longer was 16.2% compared with 0% in 80 control subjects. Six patients (3.6%) in the methadone group presented torsades de pointes. QTc length was weakly but significantly associated with methadone daily dose (Spearman rank correlation coefficient, 0.20; P<.01). Multivariate regression analysis allowed attribution of 31.8% of QTc variability to methadone dose, cytochrome P-450 3A4 drug-drug interactions, hypokalemia, and altered liver function. CONCLUSIONS: QT interval prolongation in methadone maintenance patients hospitalized in a tertiary care center is a frequent finding. Methadone dose, presence of cytochrome P-450 3A4 inhibitors, potassium level, and liver function contribute to QT prolongation. Long QT syndrome can occur with low doses of methadone.

Adolescent↗
PubMed2006

Prediction of pulmonary embolism in the emergency department: the revised Geneva score.

BACKGROUND: Diagnosis of pulmonary embolism requires clinical probability assessment. Implicit assessment is accurate but is not standardized, and current prediction rules have shortcomings. OBJECTIVE: To construct a simple score based entirely on clinical variables and independent from physicians' implicit judgment. DESIGN: Derivation and external validation of the score in 2 independent management studies on pulmonary embolism diagnosis. SETTING: Emergency departments of 3 university hospitals in Europe. PATIENTS: Consecutive patients admitted for clinically suspected pulmonary embolism. MEASUREMENTS: Collected data included demographic characteristics, risk factors, and clinical signs and symptoms suggestive of venous thromboembolism. The variables statistically significantly associated with pulmonary embolism in univariate analysis were included in a multivariate logistic regression model. Points were assigned according to the regression coefficients. The score was then externally validated in an independent cohort. RESULTS: The score comprised 8 variables (points): age older than 65 years (1 point), previous deep venous thrombosis or pulmonary embolism (3 points), surgery or fracture within 1 month (2 points), active malignant condition (2 points), unilateral lower limb pain (3 points), hemoptysis (2 points), heart rate of 75 to 94 beats/min (3 points) or 95 beats/min or more (5 points), and pain on lower-limb deep venous palpation and unilateral edema (4 points). In the validation set, the prevalence of pulmonary embolism was 8% in the low-probability category (0 to 3 points), 28% in the intermediate-probability category (4 to 10 points), and 74% in the high-probability category (> or =11 points). LIMITATIONS: Interobserver agreement for the score items was not studied. CONCLUSIONS: The proposed score is entirely standardized and is based on clinical variables. It has sustained internal and external validation and should now be tested for clinical usefulness in an outcome study.

Aged↗
PubMed2006

A prediction rule to identify low-risk patients with pulmonary embolism.

BACKGROUND: A simple prognostic model could help identify patients with pulmonary embolism who are at low risk of death and are candidates for outpatient treatment. METHODS: We randomly allocated 15,531 retrospectively identified inpatients who had a discharge diagnosis of pulmonary embolism from 186 Pennsylvania hospitals to derivation (67%) and internal validation (33%) samples. We derived our rule to predict 30-day mortality using classification tree analysis and patient data routinely available at initial examination as potential predictor variables. We used data from a European prospective study to externally validate the rule among 221 inpatients with pulmonary embolism. We determined mortality and nonfatal adverse medical outcomes across derivation and validation samples. RESULTS: Our final model consisted of 10 patient factors (age > or = 70 years; history of cancer, heart failure, chronic lung disease, chronic renal disease, and cerebrovascular disease; and clinical variables of pulse rate > or = 110 beats/min, systolic blood pressure < 100 mm Hg, altered mental status, and arterial oxygen saturation < 90%). Patients with none of these factors were defined as low risk. The 30-day mortality rates for low-risk patients were 0.6%, 1.5%, and 0% in the derivation, internal validation, and external validation samples, respectively. The rates of nonfatal adverse medical outcomes were less than 1% among low-risk patients across all study samples. CONCLUSIONS: This simple prediction rule accurately identifies patients with pulmonary embolism who are at low risk of short-term mortality and other adverse medical outcomes. Prospective validation of this rule is important before its implementation as a decision aid for outpatient treatment.

Age Factors↗
PubMed2006

Value of D-dimer testing for the exclusion of pulmonary embolism in patients with previous venous thromboembolism.

BACKGROUND: D-dimer levels remain elevated in many patients after completion of a 6-month anticoagulant drug course for a first episode of venous thromboembolism (VTE), which may limit the clinical usefulness of D-dimer testing for ruling out a possible recurrence. METHODS: We assessed the safety and usefulness of D-dimer testing in patients with suspected pulmonary embolism (PE) who had experienced a previous VTE. We analyzed data from 2 outcome studies that enrolled 1721 consecutive emergency department patients with clinically suspected PE. Information on the existence of a previous episode of VTE was abstracted from the database. All the patients underwent a sequential diagnostic workup, including an enzyme-linked immunosorbent assay D-dimer test and a 3-month follow-up. RESULTS: The proportion of confirmed PE was 24.1% (415/1719); PE was ruled out by a negative D-dimer test result in 32.7% (462/1411) of the patients without previous VTE but in only 15.9% (49/308) of the patients with previous VTE (P<.001). The 3-month thromboembolic risk was 0% (95% confidence interval, 0.0%-7.9%) in patients with previous VTE and a negative D-dimer test result. The 2-fold lower chance of a negative D-dimer test result in patients with previous VTE was independent of older age, active malignancy, fever, and recent surgery. CONCLUSIONS: In patients with suspected PE and previous VTE, a negative D-dimer test result seems to allow safely ruling out a recurrent event. However, the proportion of negative results is lower in such patients, definitely reducing the clinical usefulness of the D-dimer test in that subgroup.

Adult↗
PubMed2006

Effect of teaching context and tutor workshop on tutorial skills.

Effective faculty development workshops are essential to develop and sustain the quality of faculty's teaching. In an integrated problem-based curriculum, tutors expressed the needs to further develop their skills in facilitating students' content learning and small-group functioning. Based on the authors' prior observations that tutors' performance depends on their teaching context, a workshop was designed not only tailored to the tutors' needs but also organized within their respective teaching unit. The purposes of this study are (1) to evaluate whether this workshop is effective and improves tutors' teaching skills, and (2) to assess whether workshop effectiveness depends on tutors' performance before the workshop and on their teaching unit environment. Workshop effectiveness was assessed using (a) tutors' perception of workshop usefulness and of their improvement in tutorial skills, and (b) students' ratings of tutor performance before and after the workshop. In addition, an analysis of variance model was designed to analyse how tutors' performance before the workshop and their teaching unit influence workshop effectiveness. Tutors judged the workshop as helpful in providing them with new teaching strategies and reported having improved their tutorial skills. Workshop attendance enhanced students' ratings of tutors' knowledge of problem content and ability to guide their learning. This improvement was also long-lasting. The workshop effect on tutor performance was relative: it varied across teaching units and was higher for tutors with low scores before the workshop. A workshop tailored to tutors' needs and adapted to their teaching unit improves their tutorial skills. Its effectiveness is, however, influenced by tutors' level of performance before the workshop and by the environment of their teaching unit. Thus, to be efficient, the design of a workshop should consider not only individual tutors' needs, but also the background of their teaching units, with special attention to their internal organization and tutor group functioning.

Analysis of Variance↗
PubMed2006

Live or computerized simulation of clinical encounters: do clinicians work up patient cases differently?

Computer simulation of clinical encounters is increasingly used in clinical settings to train patient work-up. The aim of this prospective, controlled study was to compare the characteristics of data collection and diagnostic exploration of physicians working up cases with a standardized patient and in a computerized simulation. Six clinicians of different clinical experience in internal medicine worked up three cases with a standardized patient and through a computer simulation allowing free inquiry. After each encounter, we asked the subjects to justify the information collected and to comment on their working diagnoses. The characteristics of data collected and working diagnoses generated were assessed and compared, according to the simulation method used. In the computer simulation, physicians limited their data collection and focused earlier and more specifically on information and working diagnoses with high levels of relevance. They reached a similar diagnostic accuracy and made decisions of a similar relevance. Computer simulation with a free-inquiry approach reproduces the data collection and the diagnostic exploration observed in a standardized-patient simulation and promotes an early collection of relevant data. Its contribution to extend the competence of learners in clinical settings should be further evaluated.

Clinical Competence↗
PubMed2006

Contemporary approach to the diagnosis of non-massive pulmonary embolism.

PURPOSE OF REVIEW: Minimally invasive diagnostic strategies for pulmonary embolism are in constant evolution, integrating new diagnostic tools along with the better use of clinical information. RECENT FINDINGS: In the past year, several reports have provided more data on the value of clinical signs and symptoms for diagnosing pulmonary embolism and improved clinical prediction rules for pulmonary embolism. Among the diagnostic tools, the use of multislice computed tomography of the chest received further validation, whereas the yield of bedside tests, such as the D-dimer test or alveolar dead-space measurement, have been further investigated. Furthermore, data linking good outcomes with appropriate diagnostic strategies in patients with suspected pulmonary embolism were reported this year for the first time. SUMMARY: These new data allow a more evidence-based and cost-effective approach to patients with suspected non-massive pulmonary embolism. Multislice computed tomography is replacing other imaging tests. More research should be performed on the role of lower limb venous compression ultrasonography, and on how to select patients in whom pulmonary embolism should be suspected and investigated.

Humans↗
PubMed2006

Diagnosis of pulmonary embolism: in transition.

PURPOSE OF REVIEW: To discuss reports published in 2005 on the diagnosis of clinically suspected nonmassive pulmonary embolism. RECENT FINDINGS: Progress has been made in assessing the clinical probability of pulmonary embolism, in addressing diagnosis in the elderly, in evaluating the diagnostic performance of single-detector and multidetector row helical computed tomography, and in the role of D-dimer measurement and lower limb venous compression ultrasonography in the diagnostic work-up of pulmonary embolism. SUMMARY: Diagnosing venous thromboembolism depends mainly on noninvasive diagnostic tools that are used sequentially. In most patients, a noninvasive work-up is feasible and the diagnostic algorithms are becoming simpler. This review focuses on developments in clinical probability assessment, pulmonary embolism in the elderly, potential new uses of D-dimer measurement, advent of multidetector row helical computed tomography, and utility of ultrasonography in detecting deep vein thrombosis in patients with suspected pulmonary embolism. With the development of potentially more sensitive diagnostic tests for pulmonary embolism, physicians are now facing the risk of overdiagnosis and hence overtreatment. The issue will no longer be just to detect clots but to identify patients who must be treated using anticoagulants, a complicated question.

Aged↗
PubMed2006

Brief report: beyond clinical experience: features of data collection and interpretation that contribute to diagnostic accuracy.

BACKGROUND: Clinical experience, features of data collection process, or both, affect diagnostic accuracy, but their respective role is unclear. OBJECTIVE, DESIGN: Prospective, observational study, to determine the respective contribution of clinical experience and data collection features to diagnostic accuracy. METHODS: Six Internists, 6 second year internal medicine residents, and 6 senior medical students worked up the same 7 cases with a standardized patient. Each encounter was audiotaped and immediately assessed by the subjects who indicated the reasons underlying their data collection. We analyzed the encounters according to diagnostic accuracy, information collected, organ systems explored, diagnoses evaluated, and final decisions made, and we determined predictors of diagnostic accuracy by logistic regression models. RESULTS: Several features significantly predicted diagnostic accuracy after correction for clinical experience: early exploration of correct diagnosis (odds ratio [OR] 24.35) or of relevant diagnostic hypotheses (OR 2.22) to frame clinical data collection, larger number of diagnostic hypotheses evaluated (OR 1.08), and collection of relevant clinical data (OR 1.19). CONCLUSION: Some features of data collection and interpretation are related to diagnostic accuracy beyond clinical experience and should be explicitly included in clinical training and modeled by clinical teachers. Thoroughness in data collection should not be considered a privileged way to diagnostic success.

Clinical Competence↗
PubMed2006

Influence of specific alternative diagnoses on the probability of pulmonary embolism.

The presence and likelihood of an alternative diagnosis to pulmonary embolism is an important variable of the Wells' prediction rule for establishing clinical probability. We assessed whether evoking specific alternative diagnoses would reduce the probability of pulmonary embolism enough to forego further testing. We retrospectively studied a cohort of 965 consecutive patients admitted for suspicion of pulmonary embolism at three medical centers in Europe in whom the presence of an alternative diagnosis at least as likely as pulmonary embolism was recorded before diagnostic testing. We divided the patients into 15 categories of alternative diagnoses evoked. We then assessed the prevalence of pulmonary embolism in each diagnostic category and compared it to the prevalence of pulmonary embolism in a reference group (patients with no alternative diagnosis or a diagnosis less likely than pulmonary embolism). The prevalence of pulmonary embolism in the reference group was 48%. The presence of an alternative diagnosis as or more likely strongly reduced the probability of pulmonary embolism (OR 0.15, 95% CI: 0.1-0.2, p < 0.01). In almost every diagnostic category, the prevalence of pulmonary embolism was much lower than in the reference group with an odds ratio below or near 0.2. Bronchopneumonia (OR 0.4, 95% CI 0.2 to 0.7) and cancer (OR 0.6, 95% CI 0.3 to 1.5) reduced the likelihood of pulmonary embolism to a lower extent. Evoking an alternative diagnosis at least as likely as pulmonary embolism reduces the probability of the disease, but this effect is never large enough to allow ruling it out without further testing, especially when bronchopneumonia or cancer are the alternative diagnoses considered.

Bronchopneumonia↗