Pierre-Nicolas Carron

Traumatic mitral valve injury after blunt chest trauma: a case report and review of the literature.

Mitral valve injury after blunt chest trauma is a rare occurrence. We recently admitted a patient with severe traumatic mitral regurgitation who was successfully treated with surgery. Review of the literature aimed at taking an inventory of cases of traumatic nonpenetrating mitral insufficiency that were operated on, since the earliest report in 1964. Eighty-two cases were found and analyzed allowing for a better understanding of the epidemiology, etiology, natural history, pathology, and treatment of this rare condition. The most common lesions reach the papillary muscles (PM), followed by the chordae and then the mitral valve leaflets. Among the 82 cases reported that have been treated with surgery, 57% required a valve replacement. More than half of the patients had a PM injury with a complete or partial rupture. When the rupture is complete, and especially when it involves the anterior PM, the clinical picture is most always acute with clinically important hemodynamic repercussions, often necessitating emergency surgery, most of the time with mitral valve replacement. One must always suspect traumatic mitral injury after blunt chest trauma. The most common mitral lesions affect the PM. The clinical course can be indolent or devastating, and most often requires urgent or delayed surgical treatment, either with mitral valve repair or replacement.

Acute stroke chameleons in a university hospital: Risk factors, circumstances, and outcomes

Objective: To identify risk factors, circumstances, and outcomes for individuals with acute ischemic stroke (AIS) chameleons (AIS-C) arriving in the emergency department of a university hospital. Methods: We retrospectively reviewed all patients with AIS from the prospectively constructed Acute Stroke Registry and Analysis of Lausanne during 8.25 years. AIS-C were defined as a failure to suspect stroke or as incorrect exclusion of stroke diagnosis. They were compared with patients diagnosed correctly at the time of admission. Results: Forty-seven of 2,200 AIS were missed (2.1%). These AIS-C were either very mild or very severe strokes. Multivariate analysis showed a younger age in patients with AIS-C (odds ratio [OR] per year 0.98, p < 0.01), less prestroke statin treatment (OR 0.29, p = 0.04), and lower diastolic admission blood pressure (OR 0.98 p = 0.04). They showed less eye deviation (OR 0.21, p = 0.04) and more cerebellar strokes (OR 3.78, p < 0.01). AIS-C were misdiagnosed as other neurologic (42.6% of cases) or nonneurologic (17.0%) disease, as unexplained decreased level of consciousness (21.3%), and as concomitantly present disease (19.1%). At 12 months, patients with AIS-C had less favorable outcomes (adjusted OR 0.21, p < 0.01) and higher mortality (adjusted OR 4.37, p < 0.01). Conclusions: AIS are missed in patients with younger age with a lower cerebrovascular risk profile and may be masked by other acute conditions. Patients with chameleons present more often with milder strokes or coma, fewer focal signs and cerebellar strokes, and have higher disability and mortality rates at 12 months. These findings may be used to raise awareness in emergency departments to recognize and treat such patients appropriately.

Accuracy of prehospital triage of trauma patients by emergency physicians: a retrospective study in western Switzerland.

Objective Accurate identification of major trauma patients in the prehospital setting positively affects survival and resource utilization. Triage algorithms using predictive criteria of injury severity have been identified in paramedic-based prehospital systems. Our rescue system is based on prehospital paramedics and emergency physicians. The aim of this study was to evaluate the accuracy of the prehospital triage performed by physicians and to identify the predictive factors leading to errors of triage. Methods Retrospective study of trauma patients triaged by physicians. Prehospital triage was analyzed using criteria defining major trauma victims (MTVs, Injury Severity Score >15, admission to ICU, need for immediate surgery and death within 48 h). Adequate triage was defined as MTVs oriented to the trauma centre or non-MTV (NMTV) oriented to regional hospitals. Results One thousand six hundred and eighti-five patients (blunt trauma 96%) were included (558 MTV and 1127 NMTV). Triage was adequate in 1455 patients (86.4%). Overtriage occurred in 171 cases (10.1%) and undertriage in 59 cases (3.5%). Sensitivity and specificity was 90 and 85%, respectively, whereas positive predictive value and negative predictive value were 75 and 94%, respectively. Using logistic regression analysis, significant (P<0.05) predictors of undertriage were head or thorax injuries (odds ratio >2.5). Predictors of overtriage were paediatric age group, pedestrian or 2 wheel-vehicle road traffic accidents (odds ratio >2.0). Conclusion Physicians using clinical judgement provide effective prehospital triage of trauma patients. Only a few factors predicting errors in triage process were identified in this study.

High-fidelity simulation in the nonmedical domain: practices and potential transferable competencies for the medical field.

Simulation is a promising pedagogical tool in the area of medical education. High- fidelity simulators can reproduce realistic environments or clinical situations. This allows for the practice of teamwork and communication skills, thereby enhancing reflective reasoning and experiential learning. Use of high-fidelity simulators is not limited to the medical and aeronautical fields, but has developed in a large number of nonmedical organizations as well. The techniques and pedagogical tools which have evolved through the use of nonmedical simulations serve not only as teaching examples but also as avenues which can help further the evolution of the concept of high-fidelity simulation in the field of medicine. This paper presents examples of high-fidelity simulations in the military, maritime, and aeronautical fields. We compare the implementation of high-fidelity simulation in the medical and nonmedical domains, and discuss the possibilities and limitations of simulators in medicine, based on recent nonmedical applications.

Stab wounds in a Swiss emergency department: a series of 80 consecutive cases

BACKGROUND Interpersonal violence is a worldwide social reality which seems to increasingly affect even the safest of countries, such as Switzerland. In this country, road traffic accidents, as well as professional and recreational activities, are the main providers of trauma-related injuries. The incidence of penetrative trauma related to stab wounds seems to be regularly increasing in our ED. The question arises of whether our strategies in trauma management are adapted to deal efficiently with these injuries. METHODS To answer this question, the study analysed patients admitted for intentional penetrative injuries in a tertiary urban emergency department (ED) during a 23 month period. Demographics, conditions of the assault, injury type and treatments applied were analysed. RESULTS Eighty patients admitted due to an intentional penetrating trauma accounted for 0.2% of the surgical practice of our ED. The assault occurred equally in a public or a private context, mainly affecting young males during the night and the weekend. Sixty six patients (83%) were treated as out-patients. Only 10 patients needed surgery. None of them required damage control surgery. No patient died and the mean hospital stay was 5.5 days. CONCLUSIONS The prevalence of stab wounds in Switzerland is low. These injuries rarely need complex, surgical procedures. Observational strategies should be considered according to the patient status.

Management of the effects of exposure to tear gas

#### Summary points Despite the frequent use of riot control agents by European law enforcement agencies, limited information exists on this subject in the medical literature. The effects of these agents are typically limited to minor and transient cutaneous inflammation, but serious complications and even deaths have been reported. During the 1999 World Trade Organisation meeting and at the 2001 Summit of the Americas in Quebec, exposure to tear gas was the most common reason for medical consultations.1 2 Primary and emergency care physicians play a role in the first line management of patients as well as in the identification of those at risk of complications from exposure to riot control agents. In 1997 the National Poisons Information Service in England received 597 inquiries from doctors seeking advice about problems related to crowd control.3 Our article reviews the different riot control agents, including the most common tear gases and pepper sprays, and provides an up to date overview of related medical sequelae. We searched the following resources for relevant information on the medical toxicity and management of acute exposure to tear gas and pepper spray: Medline, PreMedline, Embase, CINAHL, SCIRUS, the Cochrane Library, ISI Web of Knowledge, Toxnet, Google Scholar, and personal archives. We used the subject headings “riot control agents”, “pepper spray”, “lacrimator”, “tear gas”, “irritants”, “incapacitating agents”, as well as the toxicological terms “chlorobenzylidene-malononitrile”, “chloroacetophenone”, “dibenzoxazepine”, “chlorodiphenylarsine” …

Cardiopulmonary resuscitation with mechanical chest compressions and simultaneous defibrillation.

In the recently published LUCAS in Cardiac Arrest (LINC) randomized trial, cardiopulmonary resuscitation (CPR) with mechanical chest compressions and simultaneous defibrillation provided no significant improvement over classic manual CPR.1 The study protocol implied the delivery of defibrillation during compressions without pausing for rhythm analysis.2 This strategy was intended to eliminate the usual preshock pause to assess rhythm and to optimize the chest compression fraction throughout cardiac resuscitation. Nevertheless, this strategy is a matter of discussion.

Coordination of Emergency Medical Services for a Major Road Traffic Accident on a Swiss Suburban Highway

On 9th April 2008 at 2:14 p.m., on the highway between Lausanne and Vevey in western Switzerland, there was a 72-car pileup including five trucks that caused one death and injured 26 others. The relatively light toll was attributed to reduced vehicular speeds on account of foggy weather, together with the quick actions and effectiveness of the first responders and the excellent collaboration between the various rescue groups (medical rescue services, fire and police departments). For the first time, we used an innovative on-site medical command and control system, based on a binomial team. Two hours after the accident, the last of the injured had been evacuated and first aid on the site had ended. This article describes how the Emergency Medical Services from the State of Vaud, Switzerland, handled the situation and how the binomial team is structured.

Histoplasma capsulatum var. duboisii infection in a patient with AIDS: rapid diagnosis using polymerase chain reaction-sequencing

We describe an original case of disseminated infection with Histoplasma capsulatum (Hc) var. duboisii in an African patient with AIDS who migrated to Switzerland. The diagnosis of histoplasmosis was suggested using direct examination of tissues and confirmed in 24 h with a panfungal polymerase chain reaction assay. The variety duboisii of Hc was established using DNA sequencing of the polymorphic genomic region OLE. Molecular tools allow diagnosis of histoplasmosis in 24 h, which is drastically shorter than culture procedures.

Retrospective analysis of 616 air-rescue trauma cases related to the practice of extreme sports

INTRODUCTION Extreme sports (ESs) are increasingly popular, and accidents due to ESs sometimes require helicopter emergency medical services (HEMSs). Little is known about their epidemiology, severity, specific injuries and required rescue operations. AIM Our aims were to perform an epidemiological analysis, to identify specific injuries and to describe the characteristic of prehospital procedures in ES accidents requiring HEMSs. METHODS This is a retrospective study, reviewing all rescue missions dedicated to ESs provided by HEMS REGA Lausanne, from 1 January 1998 to 31 December 2008. ES were classified into three categories of practice, according to the type of risk at the time of the fall. RESULTS Among the 616 cases meeting inclusion criteria, 219 (36%) were clearly high-risk ES accidents; 69 (11%) and 328 (53%) were related to potential ES, but with respectively low or indeterminate risk at the time of the fall. In the high-risk ES group, the median age was 32 years and 80% were male. Mortality at 48h was 11%, almost ten times higher than in the other two groups. The proportion of potentially life-threatening injuries (the National Advisory Committee for Aeronautics (NACA) score≥4) was 39% in the high-risk ES group and 13% in the other two groups. Thirty per cent of the cases in the high-risk ES group presented an Injury Severity Score (ISS) >15, compared with 7% in the other groups. Thoracolumbar vertebral fractures were the most common injuries with 32% of all cases having at least one, involving the T12-L2 junction in 56% of cases. The other most frequent injuries were traumatic brain injuries (16%), rib fractures (9%), pneumothorax (8%) and femoral (7%), cervical (7%), ankle (5%) and pelvic (5%) fractures. Median time on site for rescue teams was higher in the confirmed high-risk ES group, with 50% of prehospital missions including at least one environmental difficulty. CONCLUSIONS High-risk ESs led to high-energy accidents, characterized by a large proportion of severe injuries and axial traumas (spine, thorax, pelvis and proximal femur). We identified a considerable percentage of thoracolumbar vertebral fractures, mainly in the T12-L2 junction. HEMSs dedicated to high-risk ESs implied longer and more complex interventions.