Critical COVID-19 patient evacuation on an amphibious assault ship: feasibility and safety. A case series.

INTRODUCTION: An amphibious assault ship was deployed on 22 March in Corsica to carry out medical evacuation of 12 critical patients infected with COVID-19. The ship has on-board hospital capacity and is the first time that an amphibious assault ship is engaged in this particular condition. The aim is to evaluate the feasibility and safety of prolonged medical evacuation of critical patients with COVID-19. METHODS: We included 12 patients with confirmed COVID-19 infection: six ventilated patients with acute respiratory distress syndrome and six non-ventilated patients with hypoxaemia. Transfer on an amphibious assault ship lasted 20 hours. We collected patients' medical records: age, comorbidities, COVID-19 history and diagnosis, ventilation supply and ventilator settings, and blood gas results. We calculated oxygen consumption (OC). RESULTS: All patients had a medical history. The median delay from onset of symptoms to hospitalisation was 8 (7-10) days. The median Sequential Organ Failure Assessment score on admission was 3 (2-5). There was no significant increase in oxygen during ship transport and no major respiratory complication. There was no significant increase in arterial oxygen pressure to fractional inspired oxygen ratio among ventilated patients during ship transport. Among ventilated patients, the median calculated OC was 255 L (222-281) by hours and 5270 L (4908-5616) during all ship transport. Among non-ventilated patients, the median calculated OC was 120 L (120-480) by hours and 2400 L (2400-9600) during all ship transport. CONCLUSION: The present work contributes to assessing the feasibility and safety condition of critical COVID-19 evacuation on an amphibious assault ship during an extended transport. The ship needs to prepare a plan and a specialised intensive team and conduct patient screening for prolonged interhospital transfers.

Efficacy of scalp nerve blocks using ropivacaïne 0,75% associated with intravenous dexamethasone for postoperative pain relief in craniotomies.

Pain after supratentorial craniotomy is common, 55 % to 80 % of patients experience moderate to severe pain in the first 48 h(1-7). The importance of intravenous dexamethasone as an adjuvant to local anaesthetics is increasingly applied(1-7), however its role in scalp nerve blocks with ropivacaine 0.75 % remains unexplored in post-operative analgesia. We analyzed 134 supratentorial craniotomies under general anaesthesia, 46 of which had preoperatively bilateral scalp nerve blocks with ropivacaine 0.75 %. The general anaesthesia was standardized and included 8 mg of intravenous dexamethasone at the induction. The postoperative pain was assessed using the numerical rating scale with patients in the post anaesthesia care unit and subsequently every 8 h in the neurosurgery unit until the 48th hour. A NRS value above 3 led to the administration of a rescue analgesic according to the defined protocol until an efficient analgesia was obtained. Postoperative pain was controlled in both groups, however the need for rescue analgesics in the scalp nerve blocks group was reduced by 40 % (39 % vs. 65 %; p = 0.006) compared to the control group. More than 60 % of the patients from the scalp nerve blocks group had an efficient analgesia without any rescue analgesic. Peroperatively the scalp nerve blocks group showed a decrease in opioid consumption and a better hemodynamic stability. No anesthetic or chirurgical complications related to the use of scalp blocks were observed. Scalp nerve blocks associated with intravenous dexamethasone are found to be a straightforward and efficient analgesic approach during supratentorial craniotomies.

Medical evacuations of members of the French armed forces for infectious diseases in foreign operations.

OBJECTIVES: Medical evacuations from foreign settings are a major health and strategic problem for the armed forces. This work aimed to study the characteristics of French military evacuations due to infectious diseases. PATIENTS AND METHODS: We performed a retrospective study based on the registers of the French operational military staff for health to assess the characteristics of the strategic medical evacuation of French armed forces members on missions abroad between January 1, 2011 and December 31, 2016. RESULTS: Out of 4633 included cases, 301 medical evacuations (6.5%) were carried out due to infectious situations. More than half of patients were repatriated to surgical wards (162 patients, 54%), 108 patients (36%) to medical wards, 21 patients (7%) to intensive care units, six patients (2%) to an armed forces medical center, and four files (1%) were incomplete. Among infectious emergencies, malaria led to 30 evacuations (10%) including 11 to intensive care units and one death before evacuation. Infectious diseases requiring medical evacuation were most often mild and community-acquired. Most soldiers were evacuated without medical assistance. CONCLUSIONS: Infectious diseases during missions and medical repatriations carried out for infectious reasons are important epidemiological indicators to monitor. They make it possible to adapt preventive measures, training, and diagnostic and therapeutic tools which can be made available to front-line military physicians.

Anhydrous Phase B: Transmission Electron Microscope Characterization and Elastic Properties.

Anhydrous phase B and stishovite formed directly from olivine in experiments at 14 GPa and 1400 °CThe structure of anhydrous phase B is determined ab initio from precession electron diffraction tomography in transmission electron microscopyElastic and seismic properties of anhydrous phase B are calculated.

We have performed an extensive characterization by transmission electron microscopy (including precession electron diffraction tomography and ab initio electron diffraction refinement as well as electron energy loss spectroscopy) of anhydrous phase B (Anh­B) formed directly from olivine at 14 GPa, 1400 °C. We show that Anh­B, which can be considered as a superstructure of olivine, exhibits strong topotactic relationships with it. This lowers the interfacial energy between the two phases and the energy barrier for nucleation of Anh­B, which can form as a metastable phase. We have calculated the elastic and seismic properties of Anh­B. From the elastic point of view, Anh­B appears to be more isotropic than olivine. Anh­B displays only a moderate seismic anisotropy quite similar to the one of wadsleyite.

Anhydrous phase B (Anh­B) is a dense magnesium silicate with composition (Mg, Fe)14Si5O24, which is expected to form in Mg­rich or Si­depleted regions of the mantle. We show that due to strong crystallographic similarities with the crystal structure of olivine, it can form directly from it as a metastable phase. We show that Anh­B exhibits a moderate seismic anisotropy, which makes its detection difficult in the mantle.

Fat Plumes May Reflect the Complex Rheology of the Lower Mantle.

Recent tomographic imaging of the mantle below major hot spots shows slow seismic velocities extending down to the core-mantle boundary, confirming the existence of mantle plumes. However, these plumes are much thicker than previously thought. Using new laboratory experiments and scaling laws, we show that thermal plumes developing in a visco-plastic fluid present much larger diameters than plumes developing in a Newtonian fluid. Such a rheology requiring a yield stress is consistent with a lower mantle predominantly deforming by pure dislocation climb. Yield stress values between 1 and 10 MPa, implying dislocation densities between 108 and 1010 m-2, would be sufficient to reproduce the plumes morphology observed in tomographic images.

Characterization by Scanning Precession Electron Diffraction of an Aggregate of Bridgmanite and Ferropericlase Deformed at HP-HT.

Scanning precession electron diffraction is an emerging promising technique for mapping phases and crystal orientations with short acquisition times (10-20 ms/pixel) in a transmission electron microscope similarly to the Electron Backscattered Diffraction (EBSD) or Transmission Kikuchi Diffraction (TKD) techniques in a scanning electron microscope. In this study, we apply this technique to the characterization of deformation microstructures in an aggregate of bridgmanite and ferropericlase deformed at 27 GPa and 2,130 K. Such a sample is challenging for microstructural characterization for two reasons: (i) the bridgmanite is very unstable under electron irradiation, (ii) under high stress conditions, the dislocation density is so large that standard characterization by diffraction contrast are limited, or impossible. Here we show that detailed analysis of intracrystalline misorientations sheds some light on the deformation mechanisms of both phases. In bridgmanite, deformation is accommodated by localized, amorphous, shear deformation lamellae whereas ferropericlase undergoes large strains leading to grain elongation in response to intense dislocation activity with no evidence for recrystallization. Plastic strain in ferropericlase can be semiquantitatively assessed by following kernel average misorientation distributions.

[Global management of patients with ebola viral disease, experience of the Healthcare workers Treatment of Conakry, Guinea]. / Prise en charge globale du patient contaminé par le virus Ebola, expérience du Centre de traitement des soignants de Conakry, Guinée.

The Healthcare Workers Treatment Center of Conakry, Guinea, was inaugurated in january 2015. It is dedicated to the diagnosis and the treatment of healthcare workers with probable or confirmed Ebola viral disease. It is staffed by the french army medical service. The french military team may reconcile their medical practice and the ethno-cultural imperatives to optimise the patient adherence during his hospitalization.

Is critical illness polyneuropathy associated with decreased heart rate variability?

INTRODUCTION: This pilot study assessed the association between critical illness polyneuropathy (CIP) and decreased heart rate variability (HRV) in intensive care patients. METHODS: All patients admitted to the intensive care unit and expected to be ventilated for at least 72 hours were included and underwent weekly electromyograms and HRV analyses for three weeks. HRV was assessed by time domain analysis of 24h recording electrocardiograms, and alterations in HRV were assessed as the square root of the mean squared differences of successive RR intervals (RMSSD) ≤ 15. RESULTS: We evaluated 26 patients, 12 men and 14 women, median age 64 years. During follow-up, 12 patients died and 9 developed CIP. CIP was not associated with age, sex, simplified acute physiology score II and treatment agents. Altered RMSSD tended to be associated with onset of CIP (P=0.06). Altered RMSSD occurred earlier or at the same time as electromyogram abnormalities in all CIP patients, but the difference was not significant. CONCLUSION: Altered HRV, may be associated with the onset of CIP in ICU patients. Although not statistically significant (P=0.06), altered RMSSD may be a surrogate marker of CIP in ICU patients undergoing mechanical ventilation. The physiological pathway linking HRV and CIP remains uncertain.

[Whole-blood transfusion for hemorrhagic shock resuscitation: two cases in Djibouti]. / Transfusion de sang total pour la réanimation du choc hémorragique: à propos de deux cas à Djibouti.

Hemorrhagic shock requires early aggressive treatment, including transfusion of packed red blood cells and hemostatic resuscitation. In austere environments, when component therapy is not available, warm fresh whole-blood transfusion is a convenient treatment. It provides red blood cells, clotting factors, and functional platelets. Therefore it is commonly used in military practice to treat hemorrhagic shock in combat casualties. At Bouffard Hospital Center in Djibouti, the supply of packed red blood cells is limited, and apheresis platelets are unavailable. We used whole blood transfusion in two civilian patients with life-threatening non-traumatic hemorrhages. One had massive bleeding caused by disseminated intravascular coagulation due to septic shock; the second was a 39 year-old pregnant woman with uterine rupture. In both cases, whole blood transfusion (twelve and ten 500 mL bags respectively), combined with etiological treatment, enabled coagulopathy correction, hemorrhage control, and satisfactory recovery.

[Pulmonary embolism and intracranial hemorrhage: is there still an indication for a caval filter placement?]. / Embolie pulmonaire et hémorragie intracrânienne : existe-t-il encore des indications de filtre cave ?

The treatment of pulmonary embolism is mainly based on anticoagulants and intravenous thrombolysis in case of collapse. The cerebral hemorrhage is the main complication of thrombolysis and contraindicates anticoagulation. We report the case of a patient with a subdural and intraparenchymal hematoma complicating intravenous thrombolysis. The patient had persistent respiratory and hemodynamic instability related to the pursuit of embolic phenomena. The implementation of a cava filter was performed and the patient had a favorable outcome.

A precession electron diffraction study of alpha, beta phases and Dauphiné twin in quartz.

Precession electron diffraction is used to distinguish between the hexagonal beta high-temperature and the trigonal alpha low-temperature phases of SiO2 quartz. The structures just differ by a kink of the SiO4 tetrahedra arranged along spiraling chains, which induces a loss of the two-fold axis and subsequent twinning in the low-temperature phase. Conventional selected-area electron diffraction (SAED) does not enable the phases distinction since only the intensity of reflections is different. It becomes possible with precession that reduces the dynamical interactions between reflections and makes their intensity very sensitive to small variations of the electron structure factors. Distinction between the twinned individuals in the low-temperature phase is then easily made and the twin law is characterized using stereographic projections. The actual symmetry of precessed zone axis patterns is also examined in detail. Using dynamical intensity simulations, it is shown that under certain thickness conditions, the diffraction class symmetry can be observed on selected area patterns that are to be used in the case of beam sensitive materials such as quartz.

Evidence of depolymerisation of amorphous silica at medium- and short-range order: XANES, NMR and CP-SEM contributions.

This work reports medium- and short-range order of changes of amorphous silica submitted to chemical degradation. Structural changes were studied, using X-ray absorption near edge structure (XANES), nuclear magnetic resonance (29)Si NMR-MAS and controlled pressure scanning electron microscope (CP-SEM). The depolymerisation of amorphous SiO(2) compounds mainly induces the formation of Q(3) species and alkali-rich domains. The XANES Si K-edge spectra demonstrate the presence of different environments of silicon: one with four oxygen atoms and the other with a number of oxygen lower than four in agreement with previous studies.

Targeted delivery of a suicide gene to human colorectal tumors by a conditionally replicating vaccinia virus.

We have generated a thymidine kinase gene-deleted vaccinia virus (VV) (Copenhagen strain) that expressed the fusion suicide gene FCU1 derived from the yeast cytosine deaminase and uracil phosphoribosyltransferase genes. Intratumoral inoculation of this thymidine kinase gene-deleted VV encoding FCU1 (VV-FCU1) in the presence of systemically administered prodrug 5-fluorocytosine (5-FC) produced statistically significant reductions in the growth of subcutaneous human colon cancer in nude mice compared with thymidine kinase gene-deleted VV treatments or with control 5-fluorouracil alone. A limitation of prodrug therapies has often been the requirement for the direct injection of the virus into relatively large, accessible tumors. Here we demonstrate vector targeting of tumors growing subcutaneously following systemic administration of VV-FCU1. More importantly we also demonstrate that the systemic injection of VV-FCU1 in nude mice bearing orthotopic liver metastasis of a human colon cancer, with concomitant administration of 5-FC, leads to substantial tumor growth retardation. In conclusion, the insertion of the fusion FCU1 suicide gene potentiates the oncolytic efficiency of the thymidine kinase gene-deleted VV and represents a potentially efficient means for gene therapy of distant metastasis from colon and other cancers.

Modified vaccinia virus Ankara as a vector for suicide gene therapy.

Modified vaccinia virus Ankara (MVA) has been used successfully to express various antigens for the development of vaccines. Here we show that MVA can also be used as an efficient vector for the transfer of suicide genes to cancer cells. We have generated a new and highly potent suicide gene, FCU1, which encodes a fusion protein derived from the yeast cytosine deaminase and uracil phosphoribosyltransferase genes. We now describe the therapeutic benefit of using MVA to deliver and express the FCU1 gene in cancer cells. MVA-mediated transfer of the FCU1 gene to various human tumor cells results in the production of a bifunctional intracellular enzyme, such that exposure to the prodrug 5-FC suppresses the growth of the tumor cells both in vitro and in vivo. Moreover, we report a more potent tumor growth delay at lower doses of 5-FC using MVA-FCU1 in comparison to adenovirus encoding FCU1. Prolonged therapeutic levels of cytotoxic 5-FU were detected in tumors in mice treated with both MVA-FCU1 and 5-FC while no detectable 5-FU was found in the circulation. This original combination between MVA and FCU1 represents a potentially safe and attractive therapeutic option to test in man.

Seed size and seedling growth: differential response of Australian and British Fabaceae to nutrient limitation.

Seed size is widely held to exert an important influence over plant establishment, but while large seeds are often assumed to be at an advantage in nutrient-limited conditions, there is in fact, little consistent evidence to support this hypothesis. Here, we examined the interspecific relationship between seedling growth and seed size for Australian and British Fabaceae species in nutrient solutions deficient in nitrogen, phosphorus, potassium or all nutrients combined (distilled water). The British species showed no consistent link between mean seed mass and seedling growth in nutrient-limited conditions. By contrast, all four nutrient-deficient treatments yielded a significant relationship for the Australian species. Linear regression showed that growth under balanced nutrient conditions was positively associated with growth without nutrients, although in fewer cases for the British species. We suggest that habitat-specific differences in regeneration conditions and/or evolutionary history may influence the role that seed size plays in dictating how seedlings of different species respond to nutrient shortage. We recommend caution in attempts to link traits like seed size to wider patterns of plant community ecology.