Imaging features to distinguish posterior fossa ependymoma subgroups.

OBJECTIVES: Posterior fossa ependymoma group A (EPN_PFA) and group B (EPN_PFB) can be distinguished by their DNA methylation and give rise to different prognoses. We compared the MRI characteristics of EPN_PFA and EPN_PFB at presentation. METHODS: Preoperative imaging of 68 patients with posterior fossa ependymoma from two centers was reviewed by three independent readers, blinded for histomolecular grouping. Location, tumor extension, tumor volume, hydrocephalus, calcifications, tissue component, enhancement or diffusion signal, and histopathological data (cellular density, calcifications, necrosis, mitoses, vascularization, and microvascular proliferation) were compared between the groups. Categorical data were compared between groups using Fisher's exact tests, and quantitative data using Mann-Whitney tests. We performed a Benjamini-Hochberg correction of the p values to account for multiple tests. RESULTS: Fifty-six patients were categorized as EPN_PFA and 12 as EPN_PFB, with median ages of 2 and 20 years, respectively (p = 0.0008). The median EPN_PFA tumoral volume was larger (57 vs 29 cm3, p = 0.003), with more pronounced hydrocephalus (p = 0.002). EPN_PFA showed an exclusive central position within the 4th ventricle in 61% of patients vs 92% for EPN_PFB (p = 0.01). Intratumor calcifications were found in 93% of EPN_PFA vs 40% of EPN_PFB (p = 0.001). Invasion of the posterior fossa foramina was mostly found for EPN_PFA, particularly the foramina of Luschka (p = 0.0008). EPN_PFA showed whole and homogeneous tumor enhancement in 5% vs 75% of EPN_PFB (p = 0.0008). All mainly cystic tumors were EPN_PFB (p = 0.002). The minimal and maximal relative ADC was slightly lower in EPN_PFA (p = 0.02 and p = 0.01, respectively). CONCLUSION: Morphological characteristics from imaging differ between posterior fossa ependymoma subtypes and may help to distinguish them preoperatively. CLINICAL RELEVANCE STATEMENT: This study provides a tool to differentiate between group A and group B ependymomas, which will ultimately allow the therapeutic strategy to be adapted in the early stages of patient management. KEY POINTS: • Posterior fossa ependymoma subtypes often have different imaging characteristics. • Posterior fossa ependymomas group A are commonly median or lateral tissular calcified masses, with incomplete enhancement, affecting young children and responsible for pronounced hydrocephalus and invasion of the posterior fossa foramina. • Posterior fossa ependymomas group B are commonly median non-calcified masses of adolescents and adults, predominantly cystic, and minimally invasive, with total and homogeneous enhancement.

Association between hydroxocobalamin administration and acute kidney injury after smoke inhalation: a multicenter retrospective study.

BACKGROUND: The use of hydroxocobalamin has long been advocated for treating suspected cyanide poisoning after smoke inhalation. Intravenous hydroxocobalamin has however been shown to cause oxalate nephropathy in a single-center study. The impact of hydroxocobalamin on the risk of acute kidney injury (AKI) and survival after smoke inhalation in a multicenter setting remains unexplored. METHODS: We conducted a multicenter retrospective study in 21 intensive care units (ICUs) in France. We included patients admitted to an ICU for smoke inhalation between January 2011 and December 2017. We excluded patients discharged at home alive within 24 h of admission. We assessed the risk of AKI (primary endpoint), severe AKI, major adverse kidney (MAKE) events, and survival (secondary endpoints) after administration of hydroxocobalamin using logistic regression models. RESULTS: Among 854 patients screened, 739 patients were included. Three hundred six and 386 (55.2%) patients received hydroxocobalamin. Mortality in ICU was 32.9% (n = 243). Two hundred eighty-eight (39%) patients developed AKI, including 186 (25.2%) who developed severe AKI during the first week. Patients who received hydroxocobalamin were more severe and had higher mortality (38.1% vs 27.2%, p = 0.0022). The adjusted odds ratio (95% confidence interval) of AKI after intravenous hydroxocobalamin was 1.597 (1.055, 2.419) and 1.772 (1.137, 2.762) for severe AKI; intravenous hydroxocobalamin was not associated with survival or MAKE with an adjusted odds ratio (95% confidence interval) of 1.114 (0.691, 1.797) and 0.784 (0.456, 1.349) respectively. CONCLUSION: Hydroxocobalamin was associated with an increased risk of AKI and severe AKI but was not associated with survival after smoke inhalation. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03558646.

Bispectral Index Measurements Are Not Degraded During Aeromedical Evacuations.

For a decade, depth of anesthesia monitoring has become a reality in the operating room. It provides valuable help for managing anesthesia, especially for unstable patients. This might be particularly relevant during aeromedical evacuation. In this study, we aimed to assess the validity of the bispectral index (BIS) during long-range patient transportation aboard fixed-wing aircraft. BIS was recorded in 30 patients, 25 under anesthesia and 5 awake, during aeromedical evacuations performed by the French Air Force. BIS index was available and analyzable (signal quality index above 50%) more than 90% of time. Despite potential pitfalls related to mechanical or electrical interference, BIS monitor can be reliably used to monitor depth of anesthesia during individual strategic aeromedical evacuations.

[Acute inpatient treatment of severe burns]. / Prise en charge hospitalière des brûlures graves.

Acute inpatient treatment of severe burns. Acute in-hospital care of severely burned patients intricately combines surgery and intensive care. Systemic and supportive care is centered on hemodynamic management of the initial plasmorrhagic shock, airway control, enteral nutrition in order to compensate for hypercatabolism, analgesia and adjuncts. Infection is a major risk, to be prevented and managed topically. Sytemic administration of antibiotics is limited to documented sepsis. Smoke inhalation injury is diagnosed by fiberoptic bronchoscopy and managed with protective ventilation, iterative bronchoscopic cleansing, and nebulized heparin, mucolytics and bronchodilators. Emergent surgery in the burned patient includes initial treatment of associated trauma, escharrotomies, and fasciotomies in selected cases. Acute surgery is centered on early excision and skin autografts to restore cutaneous integrity. Reconstructive surgery is delayed.

Prise en charge hospitalière des brûlures graves. Le traitement hospitalier aigu des brûlés graves associe étroitement chirurgie et réanimation. Le traitement général est centré sur la gestion hémodynamique du choc plasmorragique initial, le contrôle des voies aériennes, la nutrition entérale pour compenser l'hypercatabolisme, l'analgésie-sédation, et la suppléance des défaillances. L'infection, risque majeur, est prévenue et traitée par voie locale en priorité : l'antibiothérapie systémique est réservée aux sepsis documentés. L'inhalation de fumées, de diagnostic fibroscopique, est traitée par ventilation protectrice, toilettes bronchiques itératives, et aérosols d'héparine, mucolytique et bronchodilatateur. La chirurgie du brûlé comprend, en urgence, le traitement prioritaire des traumatismes associés, les escarrotomies de décharge, voire les fasciotomies ; en phase aiguë, la restitution de l'intégrité cutanée par des excisions et autogreffes précoces ; à distance, la chirurgie réparatrice des séquelles.

Anti-HLA sensitization in extensively burned patients: extent, associated factors, and reduction in potential access to vascularized composite allotransplantation.

Extensively burned patients receive iterative blood transfusions and skin allografts that often lead to HLA sensitization, and potentially impede access to vascularized composite allotransplantation (VCA). In this retrospective, single-center study, anti-HLA sensitization was measured by single-antigen-flow bead analysis in patients with deep, second- and third-degree burns over ≥40% total body surface area (TBSA). Association of HLA sensitization with blood transfusions, skin allografts, and pregnancies was analyzed by bivariate analysis. The eligibility for transplantation was assessed using calculated panel reactive antibodies (cPRA). Twenty-nine patients aged 32 ± 14 years, including 11 women, presented with a mean burned TBSA of 54 ± 11%. Fifteen patients received skin allografts, comprising those who received cryopreserved (n = 3) or glycerol-preserved (n = 7) allografts, or both (n = 5). An average 36 ± 13 packed red blood cell (PRBC) units were transfused per patient. In sera samples collected 38 ± 13 months after the burns, all patients except one presented with anti-HLA antibodies, of which 13 patients (45%) had complement-fixing antibodies. Eighteen patients (62%) were considered highly sensitized (cPRA≥85%). Cryopreserved, but not glycerol-preserved skin allografts, history of pregnancy, and number of PRBC units were associated with HLA sensitization. Extensively burned patients may become highly HLA sensitized during acute care and hence not qualify for VCA. Alternatives to skin allografts might help preserve their later access to VCA.

In-flight auscultation during medical air evacuation: comparison between traditional and amplified stethoscopes.

OBJECTIVES: The aim of this study was to evaluate the capacity of a traditional stethoscope versus an electronically amplified one (expected to reduce background and ambient noise) to assess heart and respiratory sounds during medical transport. MATERIALS AND METHODS: It was a prospective, double-blinded, randomized performed study. One traditional stethoscope (Littmann Cardiology III; 3M, St Paul, MN) and 1 electronically amplified stethoscope (Littmann 3200, 3M) were used for our tests. Heart and lung auscultation during real medical evacuations aboard a medically configured Falcon 50 aircrafts were studied. The quality of auscultation was ranged using a numeric rating scale from 0 to 10 (0 corresponding to "I hear nothing" and 10 to "I hear perfectly"). Data collected were compared using a t-test for paired values. RESULTS: A total of 40 comparative evaluations were performed. For cardiac auscultation, the value of the rating scale was 4.53 ± 1.91 and 7.18 ± 1.88 for the traditional and amplified stethoscope, respectively (paired t-test: P < .0001). For respiratory sounds, quality of auscultation was estimated at 3.1 ± 1.95 for a traditional stethoscope and 5.10 ± 2.13 for the amplified one (paired t-test: P < .0001). CONCLUSIONS: This study showed that practitioners would be better helped in hearing cardiac and respiratory sounds with an electronically amplified stethoscope than with a traditional one during air medical transport in a medically configured Falcon 50 aircraft.

Brief report: pulmonary auscultation in the operating room: a prospective randomized blinded trial comparing electronic and conventional stethoscopes.

BACKGROUND: We compared the subjective quality of pulmonary auscultation between 2 acoustic stethoscopes (Holtex Ideal® and Littmann Cardiology III®) and an electronic stethoscope (Littmann 3200®) in the operating room. METHODS: A prospective double-blind randomized study with an evaluation during mechanical ventilation was performed in 100 patients. After each examination, the listeners using a numeric scale (0-10) rated the quality of auscultation. Auscultation quality was compared in patients among stethoscopes with a multilevel mixed-effects linear regression with random intercept (operator effect), adjusted on significant factors in univariate analysis. A significant difference was defined as P < 0.05. RESULTS: One hundred comparative evaluations of pulmonary auscultation were performed. The quality of auscultation was rated 8.2 ± 1.6 for the electronic stethoscope, 7.4 ± 1.8 for the Littmann Cardiology III, and 4.6 ± 1.8 for the Holtex Ideal. Compared with Holtex Ideal, auscultation quality was significantly higher with other stethoscopes (P < 0.0001). Compared with Littmann Cardiology III, auscultation quality was significantly higher with Littmann 3200 electronic stethoscope (ß = 0.9 [95% confidence interval, 0.5-1.3]). CONCLUSIONS: An electronic stethoscope can provide a better quality of pulmonary auscultation than acoustic stethoscopes in the operating room, yet with a magnitude of improvement marginally higher than that provided with a high performance acoustic stethoscope. Whether this can translate into a clinically relevant benefit requires further studies.

Validation of a pre-established triage protocol for critically ill patients in a COVID-19 outbreak under resource scarcity: A retrospective multicenter cohort study.

INTRODUCTION: In case of COVID-19 related scarcity of critical care resources, an early French triage algorithm categorized critically ill patients by probability of survival based on medical history and severity, with four priority levels for initiation or continuation of critical care: P1 -high priority, P2 -intermediate priority, P3 -not needed, P4 -not appropriate. This retrospective multi-center study aimed to assess its classification performance and its ability to help saving lives under capacity saturation. METHODS: ICU patients admitted for severe COVID-19 without triage in spring 2020 were retrospectively included from three hospitals. Demographic data, medical history and severity items were collected. Priority levels were retrospectively allocated at ICU admission and on ICU day 7-10. Mortality rate, cumulative incidence of death and of alive ICU discharge, length of ICU stay and of mechanical ventilation were compared between priority levels. Calculated mortality and survival were compared between full simulated triage and no triage. RESULTS: 225 patients were included, aged 63.1±11.9 years. Median SAPS2 was 40 (IQR 29-49). At the end of follow-up, 61 (27%) had died, 26 were still in ICU, and 138 had been discharged. Following retrospective initial priority allocation, mortality rate was 53% among P4 patients (95CI 34-72%) versus 23% among all P1 to P3 patients (95CI 17-30%, chi-squared p = 5.2e-4). The cumulative incidence of death consistently increased in the order P3, P1, P2 and P4 both at admission (Gray's test p = 3.1e-5) and at reassessment (p = 8e-5), and conversely for that of alive ICU discharge. Reassessment strengthened consistency. Simulation under saturation showed that this two-step triage protocol could have saved 28 to 40 more lives than no triage. CONCLUSION: Although it cannot eliminate potentially avoidable deaths, this triage protocol proved able to adequately prioritize critical care for patients with highest probability of survival, hence to save more lives if applied.

European Burns Association guidelines for the management of burn mass casualty incidents within a European response plan.

BACKGROUND: A European response plan to burn mass casualty incidents has been jointly developed by the European Commission and the European Burn Association. Upon request for assistance by an affected country, the plan outlines a mechanism for coordinated international assistance, aiming to alleviate the burden of care in the affected country and to offer adequate specialized care to all patients who can benefit from it. To that aim, Burn Assessment Teams are deployed to assess and triage patients. Their transportation priority recommendations are used to distribute outnumbering burn casualties to foreign burn centers. Following an appropriate medical evacuation, these casualties receive specialized care in those facilities. METHODS: The European Burns Association's disaster committee developed medical-organizational guidelines to support this European plan. The experts identified fields of interest, defined questions to be addressed, performed relevant literature searches, and added their expertise in burn disaster preparedness and response. Due to the lack of high-level evidence in the available literature, recommendations and specially designed implementation tools were provided from expert opinion. The European Burns Association officially endorsed the draft recommendations in 2019, and the final full text was approved by the EBA executive committee in 2022. RECOMMENDATIONS: The resulting 46 recommendations address four fields. Field 1 underlines the need for national preparedness plans and the necessary core items within such plans, including coordination and integration with an international response. Field 2 describes Burn Assessment Teams' roles, composition, training requirements, and reporting goals. Field 3 addresses the goals of specialized in-hospital triage, appropriate severity criteria, and their effects on priorities and triage. Finally, field 4 covers medical evacuations, including their timing and organization, the composition of evacuation teams and their assets, preparation, and the principles of en route care.

Burn mass casualty incidents in Europe: A European response plan within the European Union Civil Protection Mechanism.

BACKGROUND: Burn care is centralized in highly specialized burn centers in Europe. These centers are of limited capacity and may be overwhelmed by a sudden surge in case of a burn mass casualty incident. Prior incidents in Europe and abroad have sustained high standards of care through well-orchestrated responses to share the burden of care in several burn centers. A burn mass casualty incident in Romania in 2015 sparked an initiative to strengthen the existing EU mechanisms. This paper aims to provide insight into developing a response plan for burn mass casualties within the EU Civil Protection Mechanism. METHODS: The European Burns Association drafted medical guidelines for burn mass casualty incidents based on a literature review and an in-depth analysis of the Romanian incident. An online questionnaire surveyed European burn centers and EU States for burn mass casualty preparedness. RESULTS: The Romanian burn mass casualty in 2015 highlighted the lack of a burn-specific mechanism, leading to the late onset of international transfers. In Europe, 71% of respondents had existing mass casualty response plans, though only 35% reported having a burn-specific plan. A burns response plan for burn mass casualties was developed and adopted as a Commission staff working document in preparation for further implementation. The plan builds on the existing Union Civil Protection Mechanism framework and the standards of the WHO Emergency Medical Teams initiative to provide 1) burn assessment teams for specialized in-hospital triage of patients, 2) specialized burn care across European burn centers, and 3) medevac capacities from participating states. CONCLUSION: The European burn mass casualty response plan could enable the delivery of high-level burn care in the face of an overwhelming incident in an affected European country. Further steps for integration and implementation of the plan within the Union Civil Protection Mechanism framework are needed.

A simplified fluid resuscitation formula for burns in mass casualty scenarios: Analysis of the consensus recommendation from the WHO Emergency Medical Teams Technical Working Group on Burns.

BACKGROUND: Burn fluid resuscitation guidelines have not specifically addressed mass casualty with resource limited situations, except for oral rehydration for burns below 40% total body surface area (TBSA). The World Health Organization Technical Working Group on Burns (TWGB) recommends an initial fluid rate of 100 mL/kg/24 h, either orally or intravenously, beyond 20% TBSA burned. We aimed to compare this formula with current guidelines. METHODS: The TWGB formula was numerically compared with 2-4 mL/kg/%TBSA for adults and the Galveston formula for children. RESULTS: In adults, the TWGB formula estimated fluid volumes within the range of current guidelines for burns between 25 and 50% TBSA, and a maximal 20 mL/kg/24 h difference in the 20-25% and the 50-60% TBSA ranges. In children, estimated resuscitation volumes between 20 and 60% TBSA approximated estimations by the Galveston formula, but only partially compensated for maintenance fluids. Beyond 60% TBSA, the TWGB formula underestimated fluid to be given in all age groups. CONCLUSION: The TWGB formula for mass burn casualties may enable appropriate fluid resuscitation for most salvageable burned patients in disasters. This simple formula is easy to implement. It should simplify patient management including transfers, reduce the risk of early complications, and thereby optimize disaster response, provided that tailored resuscitation is given whenever specialized care becomes available.

Recommendations for burns care in mass casualty incidents: WHO Emergency Medical Teams Technical Working Group on Burns (WHO TWGB) 2017-2020.

Health and logistical needs in emergencies have been well recognised. The last 7 years has witnessed improved professionalisation and standardisation of care for disaster affected communities - led in part by the World Health Organisation Emergency Medical Team (EMT) initiative. Mass casualty incidents (MCIs) resulting in burn injuries present unique challenges. Burn management benefits from specialist skills, expert knowledge, and timely availability of specialist resources. With burn MCIs occurring globally, and wide variance in existing burn care capacity, the need to strengthen burn care capability is evident. Although some high-income countries have well-established disaster management plans, including burn specific plans, many do not - the majority of countries where burn mass casualty events occur are without such established plans. Developing globally relevant recommendations is a first step in addressing this deficit and increasing preparedness to deal with such disasters. Global burn experts were invited to a succession of Technical Working Group on burns (TWGB) meetings to: 1) review literature on burn care in MCIs; and 2) define and agree on recommendations for burn care in MCIs. The resulting 22 recommendations provide a framework to guide national and international specialist burn teams and health facilities to support delivery of safe care and improved outcomes to burn patients in MCIs.

Traum'cast: an online, open-access educational video podcast series for teaching military trauma care to all healthcare providers.

The aim of this paper was to describe the development of 'Traum'cast', an ambitious project to create a high-quality, open-access, 12-week video podcast programme providing evidence-based continuing medical education for civilian and military healthcare practitioners dedicated to the management of trauma caused by weapons of war. The management of such patients became a particular public health issue in France following the 2015 terrorist attacks in Paris, which highlighted the need for all healthcare professionals to have appropriate knowledge and training in such situations. In 2016, the French Health General Direction asked the French Military Medical Service (FMMS) to create a task force and to use its unique and considerable experience to produce high-quality educational material on key themes including war injuries, combat casualty care, triage, damage control surgery, transfusion strategies, psychological injury and rehabilitation. The material was produced by FMMS and first broadcast in French and for free, on the official FMMS YouTube channel in September 2020. Traum'cast provides evidence-based continuing medical education for civilian and military healthcare practitioners. Traum'cast is an educational innovation that meets a public health requirement.

Acute respiratory distress syndrome: performance of ventilator at simulated altitude.

BACKGROUND: Ventilation of Acute Respiratory Distress Syndrome (ARDS) is a challenge, and there is definitely a need for lack of variations between delivered and set tidal volume (Vt). We have assessed the ability of the ventilator T-birdVS02 and LTV-1000 to deliver to a lung model with ARDS a set Vt at different simulated altitudes. METHODS: We used a decompression chamber to mimic the hypobaric environment at a range of simulated cabin altitudes of 1,500, 2,500, and 3,000 m (4,000, 6,670, and 8,000 feet, respectively). Ventilators were tested with realistic parameters. Vt was set at 400 mL and 250 mL in an ARDS lung model. Comparisons of preset to actual measured values were accomplished using a t test for each altitude. RESULTS: The T-birdVS02 showed a decrease in the volume delivered. Comparisons of actual delivered Vt and set Vt demonstrated a significant difference starting at 1,500 m for a Vt set of 400 mL and at 2,500 m for Vt set of 250 mL. At these altitudes, the variations between Vt set and delivered were more than 10%. With decreasing barometric pressure, the LTV-1000 showed mostly an increase in volume delivered. Comparisons of actual delivered Vt and set Vt demonstrated a significant difference at 2,500 m for a Vt set of 400 mL and at 3,000 m for Vt set of 250 mL. The delivered Vt remained within 10% of the set Vt. CONCLUSION: Clinicians involved in aerial evacuations must keep in mind the performance and limitations of their ventilator system.

[Skin engineering for burns treatment]. / L'ingéniérie cutanée pour le traitement des brûlures graves.

Severely burned patients need effective and permanent wound coverage. The outcome of massive burn injuries has improved with the use of cultured epithelial autografts (CEA), despite their fragility, frequent failure to take, high cost and long-term tendency to contract. Combining CEA with dermal substitutes provides earlier skin closure and satisfactory functional results. Another promising line of research is skin regeneration with epidermal stem cells, which have the capacity to differentiate into keratinocytes, to promote wound repair, and to regenerate skin appendages. Human mesenchymal stem cells have been evaluated in radiation-induced skin damage.