Tobias Raupach

Slow breathing reduces sympathoexcitation in COPD.

Neurohumoral activation has been shown to be present in hypoxic patients with chronic obstructive pulmonary disease (COPD). The aims of the present study were to investigate whether there is sympathetic activation in COPD patients in the absence of hypoxia and whether slow breathing has an impact on sympathoexcitation and baroreflex sensitivity. Efferent muscle sympathetic nerve activity, blood pressure, cardiac frequency and respiratory movements were continuously measured in 15 COPD patients and 15 healthy control subjects. Baroreflex sensitivity was analysed by autoregressive spectral analysis and the alpha-angle method. At baseline, sympathetic nerve activity was significantly elevated in COPD patients and baroreflex sensitivity was decreased (5.0±0.6 versus 8.9±0.8 ms·mmHg−1). Breathing at a rate of 6 breaths·min−1 caused sympathetic activity to drop significantly in COPD patients (from 61.3±4.6 to 53.0±4.3 bursts per 100 heartbeats) but not in control subjects (39.2±3.2 versus 37.5±3.3 bursts per 100 heartbeats). In both groups, slow breathing significantly enhanced baroreflex sensitivity. In conclusion, sympathovagal imbalance is present in normoxic chronic obstructive pulmonary disease patients. The possibility of modifying these changes by slow breathing may help to better understand and influence this systemic disease.

A Randomized Placebo-Controlled Trial of Varenicline for Smoking Cessation Allowing Flexible Quit Dates

Introduction: Current smoking cessation guidelines recommend setting a quit date prior to starting pharmacotherapy. However, providing flexibility in the date of quitting may be more acceptable to some smokers. The objective of this study was to compare varenicline 1 mg twice daily (b.i.d.) with placebo in subjects using a flexible quit date paradigm after starting medication. Methods: In this double-blind, randomized, placebo-controlled international study, smokers of ≥10 cigarettes/day, aged 18–75 years, and who were motivated to quit were randomized (3:1) to receive varenicline 1 mg b.i.d. or placebo for 12 weeks. Subjects were followed up through Week 24. Subjects were instructed to quit between Days 8 and 35 after starting medication. The primary endpoint was carbon monoxide–confirmed continuous abstinence during Weeks 9–12, and a key secondary endpoint was continuous abstinence during Weeks 9–24. Results: Overall, 493 subjects were randomized to varenicline and 166 to placebo. Continuous abstinence was higher for varenicline than for placebo subjects at the end of treatment (Weeks 9–12: 53.1% vs. 19.3%; odds ratio [OR] 5.9; 95% CI, 3.7–9.4; p < .0001) and through 24 weeks follow-up (Weeks 9–24: 34.7% vs. 12.7%; OR 4.4; 95% CI, 2.6–7.5; p < .0001). Serious adverse events occurred in 1.2% varenicline (none were psychiatric) and 0.6% placebo subjects. Fewer varenicline than placebo subjects reported depression-related adverse events (2.3% vs. 6.7%, respectively). Conclusions: Varenicline 1 mg b.i.d. using a flexible quit date paradigm had similar efficacy and safety compared with previous fixed quit date studies.

Exercise intolerance and systemic manifestations of pulmonary emphysema in a mouse model

BackgroundSystemic effects of chronic obstructive pulmonary disease (COPD) significantly contribute to severity and mortality of the disease. We aimed to develop a COPD/emphysema model exhibiting systemic manifestations of the disease.MethodsFemale NMRI mice were treated 5 times intratracheally with porcine pancreatic elastase (emphysema) or phosphate-buffered saline (control). Emphysema severity was quantified histologically by mean linear intercept, exercise tolerance by treadmill running distance, diaphragm dysfunction using isolated muscle strips, pulmonary hypertension by measuring right ventricular pressure, and neurohumoral activation by determining urinary norepinephrine concentration.ResultsMean linear intercept was higher in emphysema (260.7 ± 26.8 μm) than in control lungs (24.7 ± 1.7 μm). Emphysema mice lost body weight, controls gained weight. Running distance was shorter in emphysema than in controls. Diaphragm muscle length was shorter in controls compared to emphysema. Fatigue tests of muscle strips revealed impaired relaxation in emphysema diaphragms. Maximum right ventricular pressure and norepinephrine were elevated in emphysema compared to controls. Linear correlations were observed between running distance changes and intercept, right ventricular weight, norepinephrine, and diaphragm length.ConclusionThe elastase mouse model exhibited severe emphysema with consecutive exercise limitation, and neurohumoral activation. The model may deepen our understanding of systemic aspects of COPD.

Cardiac resynchronization therapy and atrial overdrive pacing for the treatment of central sleep apnoea

The combined therapeutic impact of atrial overdrive pacing (AOP) and cardiac resynchronization therapy (CRT) on central sleep apnoea (CSA) in chronic heart failure (CHF) so far has not been investigated. We aimed to evaluate the effect of CRT alone and CRT + AOP on CSA in CHF patients and to compare the influence of CRT on CHF between CSA positive and CSA negative patients.

Summative assessments are more powerful drivers of student learning than resource intensive teaching formats

BackgroundElectrocardiogram (ECG) interpretation is a core clinical skill that needs to be acquired during undergraduate medical education. Intensive teaching is generally assumed to produce more favorable learning outcomes, but recent research suggests that examinations are more powerful drivers of student learning than instructional format. This study assessed the differential contribution of teaching format and examination consequences to learning outcome regarding ECG interpretation skills in undergraduate medical students.MethodsA total of 534 fourth-year medical students participated in a six-group (two sets of three), partially randomized trial. Students received three levels of teaching intensity: self-directed learning (two groups), lectures (two groups) or small-group peer teaching facilitated by more advanced students (two groups). One of the two groups on each level of teaching intensity was assessed in a formative, the other in a summative written ECG examination, which provided a maximum of 1% credit points of the total curriculum. The formative examination provided individual feedback without credit points. Main outcome was the correct identification of ≥3 out of 5 diagnoses in original ECG tracings. Secondary outcome measures were time spent on independent study and use of additional study material.ResultsCompared with formative assessments, summative assessments increased the odds of correctly identifying at least three out of five ECG diagnoses (OR 5.14; 95% CI 3.26 to 8.09), of spending at least 2 h/week extra on ECG self-study (OR 4.02; 95% CI 2.65 to 6.12) and of using additional learning material (OR 2.86; 95% CI 1.92 to 4.24). Lectures and peer teaching were associated with increased learning effort only, but did not augment examination performance.ConclusionsMedical educators need to be aware of the paramount role of summative assessments in promoting student learning. Consequently, examinations within medical schools need to be closely matched to the desired learning outcomes. Shifting resources from implementing innovative and costly teaching formats to designing more high-quality summative examinations warrants further investigation.

Knowledge gaps about smoking cessation in hospitalized patients and their doctors.

Background: Hospitalization is an opportune time for smoking cessation support; cessation interventions delivered by hospital physicians are effective. While general practitioners’ and outpatients’ knowledge and attitudes towards smoking cessation have been studied in great detail, in-patient cessation programmes have received less attention. Design: Questionnaire-based survey of a convenience sample of hospital physicians and in-patients at Göttingen University Hospital, Germany. Methods: All 159 physicians directly involved in bedside care on medical and surgical wards received a three-page questionnaire examining smoking status, knowledge of smoking-attributable morbidity and mortality, and their understanding of the effectiveness of methods to achieve long-term smoking cessation. Perceived barriers to the delivery of counselling and cessation services to smoking patients were identified. One thousand randomly selected patients on medical (N = 400) and surgical (N = 600) wards were invited to complete a similar questionnaire. Results: Seventy-seven physicians (response rate 48.4%) and 675 patients (67.5%) completed the questionnaire. Patients and physicians alike underestimated the smoking-attributable risk of developing smoking-related cancers and chronic obstructive lung disease. In addition, severe misperceptions regarding the effectiveness of cessation methods were noted in both populations with ‘willpower’ being thought to be most effective in achieving abstinence. Only one-third of smoking patients recalled having been counselled to quit. Physicians identified lack of time as a central barrier to counselling smoking patients. Conclusions: These findings suggest that hospitalized smokers in a large German university hospital might not be treated according to international guidelines.

Impact of teaching and assessment format on electrocardiogram interpretation skills

Medical Education 2010: 44: 731–740

Web-based collaborative training of clinical reasoning: A randomized trial

Background: Clinical reasoning skills are essential for medical practice. Problem-based collaborative learning via the internet might prove useful in imparting these skills. Aim: This randomized study assessed whether web-based learning (WBL) is superior to face-to-face problem-based learning (PBL) in the setting of a 6-week cardio-respiratory course. Methods: During winter term 2007/08, all 148 fourth-year medical students enrolled in the 6-week course consented to be randomized in small groups to diagnose a patient complaining of dyspnoea either using a virtual collaborative online module or a traditional PBL session. Clinical reasoning skills were assessed by means of a key feature examination at the end of the course. Results: No significant difference between the mean scores of both study groups was detected (p = 0.843). In virtual learning groups, costs for diagnostic tests were significantly correlated to the number of contributions to online group discussions (r = 0.881; p = 0.002). Evaluation data favored traditional PBL sessions over virtual collaborative learning. Conclusion: While virtual collaborative learning was as effective as traditional PBL regarding the acquisition of clinical reasoning skills, it was less well accepted than traditional PBL. Future research needs to determine the ideal format and time-point for computer-assisted learning in medical education.

Student perceptions of evaluation in undergraduate medical education: A qualitative study from one medical school.

BackgroundEvaluation is an integral part of medical education. Despite a wide use of various evaluation tools, little is known about student perceptions regarding the purpose and desired consequences of evaluation. Such knowledge is important to facilitate interpretation of evaluation results. The aims of this study were to elicit student views on the purpose of evaluation, indicators of teaching quality, evaluation tools and possible consequences drawn from evaluation data.MethodsThis qualitative study involved 17 undergraduate medical students in Years 3 and 4 participating in 3 focus group interviews. Content analysis was conducted by two different researchers.ResultsEvaluation was viewed as a means to facilitate improvements within medical education. Teaching quality was believed to be dependent on content, process, teacher and student characteristics as well as learning outcome, with an emphasis on the latter. Students preferred online evaluations over paper-and-pencil forms and suggested circulating results among all faculty and students. Students strongly favoured the allocation of rewards and incentives for good teaching to individual teachers.ConclusionsIn addition to assessing structural aspects of teaching, evaluation tools need to adequately address learning outcome. The use of reliable and valid evaluation methods is a prerequisite for resource allocation to individual teachers based on evaluation results.

Structured smoking cessation training for health professionals on cardiology wards: a prospective study

Background Smoking is a major cardiovascular risk factor, and smoking cessation is imperative for patients hospitalized with a cardiovascular event. This study aimed to evaluate a systems-based approach to helping hospitalized smokers quit and to identify implementation barriers. Design Prospective intervention study followed by qualitative analysis of staff interviews. Methods The prospective intervention study assessed the effects of implementing standard operating procedures (SOPs) for the provision of counselling and pharmacotherapy to smokers admitted to cardiology wards on counselling frequency. In addition, a qualitative analysis of staff interviews was undertaken to examine determinants of physician and nurse behaviour; this sought to understand barriers in terms of motivation, capability, and/or opportunity. Results A total of 150 smoking patients were included in the study (75 before and 75 after SOP implementation). Before the implementation of SOPs, the proportion of patients reporting to have received cessation counselling from physicians and nurses was 6.7% and 1.3%, respectively. Following SOP implementation, these proportions increased to 38.7% (p < 0.001) and 2.7% (p = 0.56), respectively. Qualitative analysis revealed that lack of motivation, e.g. role incongruence, appeared to be a major barrier. Conclusions Introduction of a set of standard operating procedures for smoking cessation advice was effective with physicians but not nurses. Analysis of barriers to implementation highlighted lack of motivation rather than capability or opportunity as a major factor that would need to be addressed.