Hydrocortisone and the mitogen-activated protein kinase inhibitor U0126 acutely suppress reactive oxygen species generation from circulating granulocytes after gunshot injuries in the pig

OBJECTIVE: Several external stimuli, including trauma, increase the endogenous production of reactive oxygen species that spontaneously attack vital biological molecules. In addition to their direct toxic effects, several secondary messenger systems are induced. To forestall a subsequent organ dysfunction, a short-term posttraumatic down-regulation of granulocyte function has been advocated. Corticosteroids are potent and universal anti-inflammatory agents, but they have well-known side effects. Modulation of the mitogen-activated protein kinase cascade is an alternative approach. The purpose of this study was to investigate how the posttraumatic production of reactive oxygen species can be modulated by hydrocortisone or the extracellular signal-regulated kinase inhibitor U0126. DESIGN: Prospective randomized trial. SETTING: Field hospital and research laboratory. SUBJECTS: Seventeen male pigs. INTERVENTIONS: In general anesthesia, the pigs were exposed to a standardized insult: one gunshot hitting the right femur from a distance of 25 m, and one pistol shot to the left upper abdomen from close range. Following immediate first aid treatment, the animals were transported to a nearby field hospital. According to randomization, the animals received either hydrocortisone 250 mg intravenously (group 1, n = 9) or a similar amount of saline (group 2, n = 8). The injections were given 5 mins after the last shot. Blood samples were drawn before shooting, immediately before hydrocortisone was given, and 60 mins after shooting. Circulating neutrophils were isolated, and the production of reactive oxygen species was measured fluorometrically. Neutrophils from nine randomly chosen animals (five from group 1 and four from group 2) were treated in vitro with the extracellular signal-regulated kinase inhibitor U0126. MEASUREMENTS AND MAIN RESULTS: The injuries as evaluated by the abbreviated injury scale did not differ between the animals. All survived the first 60 mins. While the in vivo production of reactive oxygen species tended to increase in the controls, a significant reduction was measured in the hydrocortisone group. Subsequent treatment with U0126 further reduced the synthesis of reactive oxygen species by about two thirds in both groups, independently of time. CONCLUSIONS: Early injection of hydrocortisone after trauma inhibits the synthesis of reactive oxygen species from circulating neutrophils. Inhibition of the extracellular signal-regulated kinase branch of the mitogen-activated protein kinase signaling cascade is an alternative approach. The powerful in vitro capacity of selective extracellular signal-regulated kinase inhibitors to reduce the posttraumatic reactive oxygen species generation deserves further investigations, and compelling evidence of their in vivo usefulness is still lacking.     

Learning from patients: students' perceptions of patient-instructors

Medical Education 2011: 45 : 913–919 OBJECTIVES Prior research on the use of patients as teachers has focused on testing the effectiveness of this practice and exploring its benefits for students. However, very little is known about the added value of patient teaching and how it relates to patient‐centred learning. The aim of this study was to explore whether there is added value in using patients as instructors in health professions education and, if there is, to examine how it is constituted. METHODS Group interviews were conducted with physiotherapy and occupational therapy students who had attended a 3‐hour optional class entitled ‘Thoughtful joint examination and respectful patient contact’. This class was delivered by patient‐instructors (PIs), who were patients with rheumatism certified to teach. A semi‐structured interview guide was used. Interviews continued until data saturation occurred (seven interviews). The interviews were recorded and transcribed verbatim. Data were analysed using content analysis. RESULTS The main finding of this study is that PI sessions facilitate a learning environment in which the content matter is complemented by the provision of realism and individual perspectives on rheumatism, the pedagogical format is characterised by authenticity and intimacy in the style of instruction and feedback, and the PI–student relationship is characterised by balanced teacher–student power relations that support the legitimacy of learning and make space for the asking of questions and the making of mistakes. CONCLUSIONS This study indicates that, in terms of power relations, the PI–student relationship differs from those between faculty teachers and students, and students and patients in the clinic. The formation of a professional identity by students may clash with the fulfilment of their learning tasks in the clinical environment. The study indicates that patient‐centredness can be fostered in the PI–student relationship. This is probably supported by the absence of faculty staff involvement in PI teaching sessions. However, further empirical research is required on what, how and why students learn from patients in different learning contexts.     

Investigating the driving performance of drivers with and without autism spectrum disorders under complex driving conditions

Purpose: The aim of this study was to investigate the driving performance of drivers with autism spectrum disorders under complex driving conditions.

Method: Seventeen drivers with autism spectrum disorders and 18 typically developed drivers participated in a driving simulator trial. Prior to the assessment, participants completed the Driving Behaviour Questionnaire and measurements of cognitive and visual-motor ability. The driving simulation involved driving in an urban area with dense traffic and unpredictable events.

Results: In comparison with the typically developed group, drivers with autism spectrum disorders reported significantly more lapses in driving, committed more mistakes on the driving simulator, and were slower to react in challenging situations, such as driving through intersections with abrupt changes in traffic lights. However, they were also less likely to tailgate other vehicles, as measured by time-to-collision between vehicles, on the driving simulator.

Conclusions: The performances of licensed drivers with autism spectrum disorders appeared to be safer in respect to car-following distance but were poorer in their response to challenging traffic situations. Driver education for individuals with autism spectrum disorders should focus on quick identification of hazards, prompt execution of responses, and effective allocation of attention to reduce lapses in driving.

• Implications for rehabilitation

• Drivers with autism spectrum disorders reported significantly more lapses during driving.

• Drivers with autism spectrum disorders were observed to be poorer in traffic scenarios requiring critical response.

• Driver education for individuals with autism spectrum disorders should focus on managing anxiety and effective attention allocation while driving.

• Driving simulators can be used as a safe means for training critical response to challenging traffic scenarios.

     

Awareness of driving disability in people with stroke tested in a simulator

The aim of this study was to explore and describe awareness of driving disability in people with driving difficulties after stroke. The study comprised a consecutive sample of 38 participants with stroke who showed difficulties in a technically advanced, interactive driving simulator. Driving ability in the simulator was measured using Performance Analysis of Driving Ability (P-Drive). Awareness of driving disability was measured using a modified version of Assessment of Awareness of Disability (AAD), measuring the discrepancy between observed driving actions and self-reported disability after a driving evaluation in a simulator. A majority of the participants (n = 36) demonstrated driving ability that was below the cut-off criterion for P-Drive. Furthermore, a majority of the items measuring awareness of driving disability were scored low, indicating that participants with stroke who did not pass a driving evaluation also had limited awareness of driving disability. A General Linear Model analysis indicated that awareness of driving disability and cognitive screening outcome explained 74% of the variance in driving ability. This study indicated that a majority of the people with stroke who fail a driving evaluation also have limited awareness of their disability, which indicates the need to address awareness in driving evaluations.     

Awareness of driving disability in people with stroke tested in a simulator

The aim of this study was to explore and describe awareness of driving disability in people with driving difficulties after stroke. The study comprised a consecutive sample of 38 participants with stroke who showed difficulties in a technically advanced, interactive driving simulator. Driving ability in the simulator was measured using Performance Analysis of Driving Ability (P-Drive). Awareness of driving disability was measured using a modified version of Assessment of Awareness of Disability (AAD), measuring the discrepancy between observed driving actions and self-reported disability after a driving evaluation in a simulator. A majority of the participants (n=36) demonstrated driving ability that was below the cut-off criterion for P-Drive. Furthermore, a majority of the items measuring awareness of driving disability were scored low, indicating that participants with stroke who did not pass a driving evaluation also had limited awareness of driving disability. A General Linear Model analysis indicated that awareness of driving disability and cognitive screening outcome explained 74% of the variance in driving ability. This study indicated that a majority of the people with stroke who fail a driving evaluation also have limited awareness of their disability, which indicates the need to address awareness in driving evaluations.     

Clinical implication of down-scatter in attenuation-corrected myocardial SPECT

BACKGROUND: Interpretation of myocardial perfusion single photon emission computed tomography (SPECT) studies is hampered by attenuation artifacts. Attenuation correction methods with simultaneous emission and transmission are now commercially available. However, it has been observed in clinical practice that attenuation correction without down-scatter correction in a 1-day rest/stress myocardial perfusion protocol may lead to serious interpretation errors. Therefore the aim of this study was to study errors resulting from down-scatter under realistic conditions, thus providing a background for the assessment of further corrections. METHODS AND RESULTS: Forty-six patients underwent myocardial perfusion scintigraphy in a 1-day technetium 99m-tetrofosmin rest-stress SPECT protocol, with a moving 153Gd line-source device for attenuation correction without down-scatter correction. Short-axis slices were quantified as inferior/anterior, septal/lateral, and apical/remainder count ratios. The changes at rest (350 MBq) and exercise (900 MBq) induced by attenuation correction were studied. Attenuation correction gave differences in apparent perfusion between rest and exercise not seen before correction. The gender differences in inferior-anterior ratio were greatly reduced after correction at rest but remained at exercise. A torso phantom study indicated that these results were due to under-correction at exercise because of down-scatter. CONCLUSIONS: Down-scatter results in an underestimation of attenuation in simultaneous emission and transmission, if not accurately accounted for. Particularly, a high-dose study compared with a low-dose study, as in the 1-day protocol, might cause serious interpretation errors.     

International Council for Standardisation in Haematology (ICSH) recommendations for collection of blood samples for coagulation testing

This guidance document has been prepared on behalf of the International Council for Standardisation in Haematology (ICSH). The aim of the document is to provide guidance and recommendations for collection of blood samples for coagulation tests in clinical laboratories throughout the world. The following processes will be covered: ordering tests, sample collection tube and anticoagulant, patient preparation, sample collection device, venous stasis before sample collection, order of draw when different sample types need to be collected, sample labelling, blood-to-anticoagulant ratio (tube filling) and influence of haematocrit. The following areas are excluded from this document, but are included in an associated ICSH document addressing processing of samples for coagulation tests in clinical laboratories: sample transport and primary tube sample stability; centrifugation; interfering substances including haemolysis, icterus and lipaemia; secondary aliquots—transport and storage; and preanalytical variables for platelet function testing. The recommendations are based on published data in peer-reviewed literature and expert opinion.     

Medical students’ learning from patient-led teaching: experiential versus biomedical knowledge

The aim of this study was to explore how medical students perceive the experience of learning from patient instructors (patients with rheumatism who teach health professionals and students) in the context of coupled faculty-led and patient-led teaching session. This was an explorative study with a qualitative approach based on focus group interviews. Analysis was based on a prior developed model of the characteristics of learning from patient instructors. The authors used this model as sensitizing concepts for the analysis of data while at the same time being open to new insights by constant comparison of old and new findings. Results showed a negotiation both between and within the students of the importance of patients’ experiential knowledge versus scientific biomedical knowledge. On one hand students appreciated the experiential learning environment offered in the PI-led sessions representing a patient-centred approach, and acknowledged the importance of the PIs’ individual perspectives and experiential knowledge. On the other hand, representing the scientific biomedical perspective and traditional step-by step teaching, students expressed unfamiliarity with the unstructured experiential learning and scepticism regarding the credibility of the patients’ knowledge. This study contributes to the understanding of the complexity of involving patients as teachers in healthcare education and initiates a discussion on how to complement faculty-led teaching with patient-led teaching involving varying degrees of patient autonomy in the planning and delivering of the teaching.     

Lived experience of driving ability following stroke

Purpose. This study describes and expands our understanding of the lived-experience of driving ability after stroke in the context of being under a driving evaluation.

Method. Four men with stroke were interviewed on three occasions. The interviews were open-ended, taped and transcribed verbatim, and analysed using Karlsson's Empirical, Phenomenological and Psychological method.

Findings. The findings revealed five main characteristics expressed in the participants' lived experiences: (1) the meaning of driving remained throughout life; (2) being questioned and advised not to drive–an untenable situation; (3) being out of control and violated by the driving evaluation; (4) driving safely (as usual) during the on-road test; and (5) perceiving consequences in everyday living.

Conclusion. The findings indicate that driving is important and taken for granted even after stroke. To lose the ability to drive was unexpected and aroused strong feelings and reactions. The present study contributes to a deeper understanding of how people with stroke experience their driving ability and the evaluation process, which can be integrated in clinical procedures to help improve information, emotional support and clinical procedures.