[A new age of mass casuality education? : The InSitu project: realistic training in virtual reality environments]. / Eine neue Ära der MANV-Ausbildung? : InSitu - Realitätsnahes Üben in virtuellen Umgebungen.

BACKGROUND: Chief emergency physicians are regarded as an important element in the care of the injured and sick following mass casualty accidents. Their education is very theoretical; practical content in contrast often falls short. Limitations are usually the very high costs of realistic (large-scale) exercises, poor reproducibility of the scenarios, and poor corresponding results. OBJECTIVES: To substantially improve the educational level because of the complexity of mass casualty accidents, modified training concepts are required that teach the not only the theoretical but above all the practical skills considerably more intensively than at present. Modern training concepts should make it possible for the learner to realistically simulate decision processes. This article examines how interactive virtual environments are applicable for the education of emergency personnel and how they could be designed. MATERIALS AND METHODS: Virtual simulation and training environments offer the possibility of simulating complex situations in an adequately realistic manner. The so-called virtual reality (VR) used in this context is an interface technology that enables free interaction in addition to a stereoscopic and spatial representation of virtual large-scale emergencies in a virtual environment. Variables in scenarios such as the weather, the number wounded, and the availability of resources, can be changed at any time. The trainees are able to practice the procedures in many virtual accident scenes and act them out repeatedly, thereby testing the different variants. RESULTS: With the aid of the "InSitu" project, it is possible to train in a virtual reality with realistically reproduced accident situations. These integrated, interactive training environments can depict very complex situations on a scale of 1:1. Because of the highly developed interactivity, the trainees can feel as if they are a direct part of the accident scene and therefore identify much more with the virtual world than is possible with desktop systems. CONCLUSION: Interactive, identifiable, and realistic training environments based on projector systems could in future enable a repetitive exercise with changes within a decision tree, in reproducibility, and within different occupational groups. With a hard- and software environment numerous accident situations can be depicted and practiced. The main expense is the creation of the virtual accident scenes. As the appropriate city models and other three-dimensional geographical data are already available, this expenditure is very low compared with the planning costs of a large-scale exercise.

[Improvement of emergency physician education through simulator training. Consideration on the basis of the model project "NASimSaar25"]. / Verbesserung der Notarztausbildung durch Simulatortraining. Betrachtung anhand des Modellprojekts "NASimSaar25"

BACKGROUND: Prehospital emergency medicine is a challenge for trainee emergency physicians. Rare injuries and diseases as well as patients in extreme age groups can unexpectedly face emergency physicians. In the regulations on medical education the German Medical Association requires participation in 50 emergency missions under the supervision of an experienced emergency physician. This needs to be improved because on-the-job training does not generally represent the whole spectrum of emergency medicine and a good and structured training under on call conditions is nearly impossible. AIM: The subject of the model project described was whether practical training for emergency physicians can be achieved by participation in simulation training instead of real emergency situations. MATERIAL AND METHODS: After modification of the Saarland regulations on medical education it was possible to replace up to 25 participations in emergency missions by simulation training. The concept of the course NASimSaar25 requires participants to complete 25 simulator cases in 3 days in small training groups. Emergency situations from all medical disciplines need to be treated. A special focus is on the treatment of life-threatening and rare diseases and injuries. Modern simulators and actors are used. The debriefings are conducted by experienced tutors based on approved principles. Medical contents, learning targets from the field of crew resource management (CRM) and soft skills are discussed in these debriefings. RESULTS: Education in the field of emergency medicine can be improved by simulator-based learning and training. However, practical work under a tutor in real and clinical experience cannot be completely replaced by simulation. Simulator training can only be successful if theoretical knowledge has already been acquired. CONCLUSION: A simulator-based course concept can result in an improvement of emergency medical education. The model project NASimSaar25 was well received by the target audience and mostly very well evaluated in terms of learning and reality. If this project becomes established the demand on simulation-based training will increase. The training should achieve a consistent standard of quality.

Mobile stroke unit for diagnosis-based triage of persons with suspected stroke.

BACKGROUND: In this feasibility study, we tested whether prehospital diagnostic stroke workup enables rational decision-making regarding treatment and the target hospital in persons with suspected stroke. METHODS: A mobile stroke unit that delivers imaging (including multimodal brain imaging with CT angiography and CT perfusion), point-of-care-laboratory analysis, and neurologic expertise directly at the emergency site was analyzed for its use in prehospital diagnosis-based triage of suspected stroke patients. RESULTS: We present 4 complementary cases with suspected stroke who underwent prehospital diagnostic workup that enabled direct diagnosis-based treatment decisions and reliable triage regarding the most appropriate medical facility for that individual, e.g., a primary hospital vs specialized centers of a tertiary hospital. CONCLUSIONS: This preliminary report demonstrates the feasibility of prehospital diagnostic stroke workup for immediate etiology-specific decision-making regarding the necessary time-sensitive stroke treatment and the most appropriate target hospital.

Effects of haemofiltration and mannitol treatment on cardiopulmonary-bypass induced immunosuppression.

Cardiac surgery using cardiopulmonary bypass (CPB) causes a systemic inflammatory response. Additionally, an impairment of the responsiveness of peripheral blood mononuclear cells (PBMC) to further immunological stimuli has been observed. The aim of our present study was to evaluate the ability of antioxidant therapy with mannitol or haemofiltration during CPB to modulate this immunosuppression after CPB. Forty-five patients undergoing elective heart-surgery were prospectively enrolled and randomized into three groups (control, mannitol, haemofiltration). Blood samples were taken after induction of anaesthesia (T1), 20 min after CPB (T2) and 24 h post-operatively (T3). Expression density of the monocytic surface receptor CD14, HLA-DR expression and cytokine release (TNF-alpha and IL10) after lipopolysaccharide-stimulation were evaluated. At T2, the CD14(dim) cell population was maintained in both intervention groups while in the control group there was a decrease of this proinflammatory monocytic phenotype. No significant differences regarding HLA-DR expression or cytokine release could be demonstrated. This study shows that the suppression of the stimulated immune response after CPB can potentially be alleviated by mannitol or haemofiltration in an experimental in-vitro setting. In the light of data showing that this depression of the immune response might affect the post-operative course of patients, these results could have a potential clinical relevance.

Experimental cooling-induced preconditioning attenuates skin flap failure.

BACKGROUND: Microvascular perfusion failure is a leading cause of tissue necrosis in reconstructive surgery. In the present experimental study the effect of local hypothermia was investigated as a possible preconditioning procedure that could induce stress proteins such as heat-shock protein (HSP) 70 and HSP-32 (haem oxygenase (HO) 1). The effect on flap microcirculation and survival was also studied. METHODS: Ears of hairless mice were subjected to local hypothermia (30 min, 4 degrees C) 24 h before flap creation. A pedicled flap was elevated by incision of four-fifths of the base of the ear. Microcirculatory dysfunction and tissue necrosis were analysed quantitatively over 5 days by means of intravital fluorescence microscopy. HO-1 and HSP-70 protein expression were determined by western blot analysis. HO-1 distribution within the flap tissue was also analysed by immunohistochemistry. Animals with unconditioned flaps served as controls. RESULTS: Cooling induced a marked expression of HO-1 without induction of HSP-70 protein. This was paralleled by a significant improvement in microvascular perfusion (P < 0.050) that was predominantly regulated by the dilatation of nutritive capillaries. The cooling-mediated improvement in microcirculation resulted in a significant reduction in final flap necrosis (P < 0.050). CONCLUSION: In this experimental study preoperative cooling was associated with the expression of HO-1 and was an effective conditioning procedure.

Hyperthermia-induced HSP expression correlates with improved rat renal isograft viability and survival in kidneys harvested from non-heart-beating donors.

Transient sublethal hyperthermia followed by recovery from heat stress, referred to as heat shock preconditioning, exerts a protective effect on ischemia/reperfusion-induced injury in many systems. This effect is considered to be correlated to heat shock proteins (HSPs) and might be a critical factor in kidney graft function and survival. This study was designed to examine the impact of heat shock preconditioning on kidney isograft function and survival in a model utilizing non-heart-beating (NHB) donors. Four groups of male Lewis rats (n = 10/group) subjected either to whole body hyperthermia (groups A and C) or to sham anesthesia (groups B and D) were allowed 24 h recovery. Thereafter, 20 min of warm ischemia (A/B), and in a separate set of experiments 40 min of warm ischemia (C/D), were induced by suprarenal aortic cross clamping before renal procurement. After 24-h preservation with University of Wisconsin solution at 4 degrees C, orthotopic kidney transplantations were performed to syngeneic bilaterally nephrectomized recipients. Tissue specimens were taken to determine HO-1/HSP32, 72, and 90 induction by Western blot analysis. Renal function was measured by means of serum creatinine and creatinine clearance on days 0, 3, and 7 as well as urine volume, protein content, and creatinine levels daily. HO-1/HSP32 and HSP72 were found to be expressed constitutively. Moreover, heat shock strongly induced renal HSP72 and HSP32/HO-1, and to a lesser extent HSP90, expression. For recipients of group A grafts, the graft survival rate was 10/10, whereas it was 7/10 (70 %) in recipients of group B grafts (log rank p < 0.05). Following 40 min of warm ischemia, 6/10 (60 %) recipients survived, whereas all sham treated animals died with anuria within 6 days (log rank p = 0.01). Heat shock preconditioning strongly improved graft viability and reduced functional impairment. Creatinine clearance (CRC) on day 3 post Tx was 0.43 +/- 0.24 ml/min in preconditioned animals (group A) and 0.07 +/- 0.09 ml/min (p < 0.001) in sham preconditioned (group B), whereas it was 0.91 +/- 0.33 ml/min and 0.03 +/- 0.02 ml/min (p < 0.00 001) on day 7 post Tx. Following 40 min NHB time, CRC in survivors of preconditioned graft recipients (group C) was 0.32 +/- 0.2 ml/min (day 3 post Tx) and 0.23 +/- 0.08 ml/min (day 7 post Tx) and was significantly better than CRC of group B (p < 0.01 and p < 0.00001, respectively). CRCs prior to NHB procedures were comparable in all animals ranging between 1.31 and 1.72 ml/min. Serum creatinine as well as proteinuria were significantly increased after transplantation in both groups but recovered within 5 days in recipients of preconditioned grafts, whereas kidneys from donors without HP did not recover function. Histological alterations were also diminished following HP. Hyperthermic preconditioning induces strong and long lasting HO-1/HSP32, HSP72, and HSP90 expression in rat kidneys. HP increases survival following transplantation and improves renal graft function including proteinuria, volume output, and creatinine clearance. HSP induction might be used to develop novel approaches in clinical transplantation.

[Tissue protection by ischemic preconditioning depends mainly on expression of heat shock protein 32]. / Gewebeprotektion durch ischämische Präkonditionierung beruht massgeblich auf der Expression von Hitzeschockprotein 32.

Using the hairless mouse ear skin flap model we demonstrate that HSP-32 expression has to be considered as a significant mechanism of ischemic preconditioning-induced protection of critically perfused tissue.