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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.dsr.2008.03.010 Byline: B. Shillito (a)(b), G. Hamel (a)(c), C. Duchi (d), D. Cottin (a), J. Sarrazin (e), P.-M. Sarradin (e), J. Ravaux (a)(b), F. Gaill (a)(b) Keywords: Pressurized recovery; Deep sea; Shrimp; Fish Abstract: The deep sea is an extremely diverse habitat, which is now threatened by human activity. Means for evaluating the response of deep-sea creatures to environmental perturbation are limited because of lethal decompression effects during sampling. The addressing of this issue requires that target species be (i) captured at depth, (ii) recovered at natural pressure, (iii) submitted to in vivo investigations. Although a single container may meet these requirements, we believe that using several dedicated cells greatly expands experimental possibilities. Accordingly, we have designed a new sampling system which has been named PERISCOP and which has accounted for the selective capture and recovery of live animals from depths exceeding 2000m. Three hydrothermal vent shrimp species were sampled on the Mid-Atlantic Ridge, from depths of 1700 and 2300m. In addition, a fish caught at 2300m depth reached the surface in very good condition. This is by far the deepest record for the pressurized recovery of a live deep-sea fish. Our prototype aims at making pressurized recovery a more efficient and practical process. Finally, future evolutions of sampling methods are discussed based on the present design of the PERISCOP. Author Affiliation: (a) Universite Pierre et Marie Curie, 7 Quai St-Bernard, Batiment A, 75252 Paris Cedex 05, France (b) UMR CNRS 7138 'Systematique, Adaptation et Evolution', 7 Quai St-Bernard, Batiment A, 75252 Paris Cedex 05, France (c) UMR CNRS 7590, Institut de Mineralogie et de Physique des Milieux Condenses (IMPMC), 140, Rue de Lourmel, Paris 75015, France (d) Genavir, DESM/SEI, Zone portuaire de Bregaillon, BP 330, 83507 La Seyne/Mer, France (e) Ifremer Brest, DEEP/Laboratoire Environnement Profond, BP 70, F-29280 Plouzane, France Article History: Received 15 November 2007; Revised 14 March 2008; Accepted 16 March 2008

The microstructural evolution of several Ce1-xLnxO2-x/2 (Ln = Nd, Er, x = 0.28; 0.59 and 0.76) sintered pellets was studied during their dissolution in 4 M HNO3 at 90 °C or 60 °C. Environmental Scanning Electron Microscopy (ESEM) experiments were developed to follow the changes in the sample microstructure and their consequences on the dissolution evolution by monitoring a constant zone of the material throughout the alteration process. The LnIII content was the parameter affecting most of the dissolution kinetics of such solid solutions. From a microstructural point of view, grain boundaries dissolve preferentially during the first dissolution step due to their relative weakness compared to the well-crystallized bulk material. Crystal defects, namely screw and edge dislocations, constitute the second kind of preferential dissolution zone and induce the formation and growth of corrosion pits, mainly of pyramidal shape on the whole surface. Both microstructural parameters are responsible for significant and non-linear increase of the reactive surface developed at the solid/liquid interface and thus important modifications of the topology. On sintered samples and even more clearly on the powdered Ce[sub 0.72]Nd[sub 0.28]O[sub 1.86] sample, the formation of a gelatinous layer resulting from processes occurring in the back-end of the dissolution process (e.g. local saturation of the leaching solution), was evidenced through ESEM observations. This gel is also presumably responsible for the progressive decrease of the normalized dissolution rate. From these observations, it appears that the study of material dissolution kinetics can clearly benefit from the monitoring of the microstructure evolution and particularly that of the reactive surface area during dissolution. [ABSTRACT FROM AUTHOR]

Objectives: Post-cardiotomy extracorporeal life support (ECLS) cannulation might occur in a general post-operative ward due to emergent conditions. Its characteristics have been poorly reported and investigated This study investigates the characteristics and outcomes of adult patients receiving ECLS cannulation in a general post-operative cardiac ward., Methods: The Post-cardiotomy Extracorporeal Life Support (PELS) is a retrospective (2000-2020), multicenter (34 centers), observational study including adult patients who required ECLS for post-cardiotomy shock. This PELS sub-analysis analyzed patients´ characteristics, in-hospital outcomes, and long-term survival in patients cannulated for veno-arterial ECLS in the general ward, and further compared in-hospital survivors and non-survivors., Results: The PELS study included 2058 patients of whom 39 (1.9%) were cannulated in the general ward. Most patients underwent isolated coronary bypass grafting (CABG, n = 15, 38.5%) or isolated non-CABG operations (n = 20, 51.3%). The main indications to initiate ECLS included cardiac arrest (n = 17, 44.7%) and cardiogenic shock (n = 14, 35.9%). ECLS cannulation occurred after a median time of 4 (2-7) days post-operatively. Most patients' courses were complicated by acute kidney injury (n = 23, 59%), arrhythmias (n = 19, 48.7%), and postoperative bleeding (n = 20, 51.3%). In-hospital mortality was 84.6% (n = 33) with persistent heart failure (n = 11, 28.2%) as the most common cause of death. No peculiar differences were observed between in-hospital survivors and nonsurvivors., Conclusions: This study demonstrates that ECLS cannulation due to post-cardiotomy emergent adverse events in the general ward is rare, mainly occurring in preoperative low-risk patients and after a postoperative cardiac arrest. High complication rates and low in-hospital survival require further investigations to identify patients at risk for such a complication, optimize resources, enhance intervention, and improve outcomes., (© 2024 The Author(s). Artificial Organs published by International Center for Artificial Organ and Transplantation (ICAOT) and Wiley Periodicals LLC.)

Objectives: Peripheral venoarterial extracorporeal membrane oxygenation (ECMO) with femoral access is obtained through unilateral or bilateral groin cannulation. Whether one cannulation strategy is associated with a lower risk for limb ischemia remains unknown. We aim to assess if one strategy is preferable., Design: A retrospective cohort study based on the Extracorporeal Life Support Organization registry., Setting: ECMO centers worldwide included in the Extracorporeal Life Support Organization registry., Patients: All adult patients (≥ 18 yr) who received peripheral venoarterial ECMO with femoral access and were included from 2014 to 2020., Interventions: Unilateral or bilateral femoral cannulation., Measurements and Main Results: The primary outcome was the occurrence of limb ischemia defined as a composite endpoint including the need for a distal perfusion cannula (DPC) after 6 hours from implantation, compartment syndrome/fasciotomy, amputation, revascularization, and thrombectomy. Secondary endpoints included bleeding at the peripheral cannulation site, need for vessel repair, vessel repair after decannulation, and in-hospital death. Propensity score matching was performed to account for confounders. Overall, 19,093 patients underwent peripheral venoarterial ECMO through unilateral ( n = 11,965) or bilateral ( n = 7,128) femoral cannulation. Limb ischemia requiring any intervention was not different between both groups (bilateral vs unilateral: odds ratio [OR], 0.92; 95% CI, 0.82-1.02). However, there was a lower rate of compartment syndrome/fasciotomy in the bilateral group (bilateral vs unilateral: OR, 0.80; 95% CI, 0.66-0.97). Bilateral cannulation was also associated with lower odds of cannulation site bleeding (bilateral vs unilateral: OR, 0.87; 95% CI, 0.76-0.99), vessel repair (bilateral vs unilateral: OR, 0.55; 95% CI, 0.38-0.79), and in-hospital mortality (bilateral vs unilateral: OR, 0.85; 95% CI, 0.81-0.91) compared with unilateral cannulation. These findings were unchanged after propensity matching., Conclusions: This study showed no risk reduction for overall limb ischemia-related events requiring DPC after 6 hours when comparing bilateral to unilateral femoral cannulation in peripheral venoarterial ECMO. However, bilateral cannulation was associated with a reduced risk for compartment syndrome/fasciotomy, lower rates of bleeding and vessel repair during ECMO, and lower in-hospital mortality., Competing Interests: Drs. Brodie’s and Lorusso’s institutions received funding from LivaNova. Drs. Brodie, Broman, and Wiedemann received funding from Xenios AG (Heilbronn, Germany). Dr. Brodie received funding from Abided, Medtronic, Abiomed, Inspira, Xenios, and Cellenkos; he received research support from ALung Technologies; and he disclosed that he is President-elect of the Extracorporeal Life Support Organization (ELSO) and Chair of the Executive Committee of the International Extracorporeal Membrane Oxygenation Network. Dr. Taccone is a scientific advisor for Eurosets and Xenios. Drs. Belliato and Broman received funding from Eurosets srl (Medolla, Italy). Dr. Belliato received funding from Eswtor Spa and Hamilton Medical. Dr. Wiedemann received funding from Abbott; he is a scientific advisor for Xenios/Fresenius. Dr. Tonna’s institution received funding from the National Heart, Lung, and Blood Institute; he disclosed that he is Chair-Elect of the ELSO Registry Committee. Drs. Tonna and Barbaro received support for article research from the U.S. National Institutes of Health. Dr. Barbaro’s institution received funding from the NHBLI (R01 HL153519, R01 HD015434, and K12 HL138039); he disclosed that he is the ELSO Registry Chair. Dr. MacLaren disclosed that he serves on the Board of Directors of ELSO. Dr. Lorusso’s institution received funding from Medtronic, LivaNova, Abiomed, Getinge, and Eurosets; he disclosed that he is a member of the Medical Advisory Board for Eurosets, HemoCue, and Xenios. The remaining authors have disclosed that they do not have any potential conflicts of interest., (Copyright © 2023 by the Society of Critical Care Medicine and Wolters Kluwer Health, Inc. All Rights Reserved.)

Background: Postcardiotomy venoarterial extracorporeal membrane oxygenation (VA ECMO) is characterized by discrepancies between weaning and survival-to-discharge rates. This study analyzes the differences between postcardiotomy VA ECMO patients who survived, died on ECMO, or died after ECMO weaning. Causes of death and variables associated with mortality at different time points are investigated., Methods: The retrospective, multicenter, observational Postcardiotomy Extracorporeal Life Support Study (PELS) includes adults requiring postcardiotomy VA ECMO between 2000 and 2020. Variables associated with on-ECMO mortality and postweaning mortality were modeled using mixed Cox proportional hazards, including random effects for center and year., Results: In 2058 patients (men, 59%; median age, 65 years; interquartile range [IQR], 55-72 years), weaning rate was 62.7%, and survival to discharge was 39.6%. Patients who died (n = 1244) included 754 on-ECMO deaths (36.6%; median support time, 79 hours; IQR, 24-192 hours), and 476 postweaning deaths (23.1%; median support time, 146 hours; IQR, 96-235.5 hours). Multiorgan (n = 431 of 1158 [37.2%]) and persistent heart failure (n = 423 of 1158 [36.5%]) were the main causes of death, followed by bleeding (n = 56 of 754 [7.4%]) for on-ECMO mortality and sepsis (n = 61 of 401 [15.4%]) for postweaning mortality. On-ECMO death was associated with emergency surgery, preoperative cardiac arrest, cardiogenic shock, right ventricular failure, cardiopulmonary bypass time, and ECMO implantation timing. Diabetes, postoperative bleeding, cardiac arrest, bowel ischemia, acute kidney injury, and septic shock were associated with postweaning mortality., Conclusions: A discrepancy exists between weaning and discharge rate in postcardiotomy ECMO. Deaths occurred during ECMO support in 36.6% of patients, mostly associated with unstable preoperative hemodynamics. Another 23.1% of patients died after weaning in association with severe complications. This underscores the importance of postweaning care for postcardiotomy VA ECMO patients., (Copyright © 2023 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Deep-sea species endemic to hydrothermal vents face the critical challenge of detecting active sites in a vast environment devoid of sunlight. This certainly requires specific sensory abilities, among which olfaction could be a relevant sensory modality, since chemical compounds in hydrothermal fluids or food odors could potentially serve as orientation cues. The temperature of the vent fluid might also be used for locating vent sites. The objective of this study is to observe the following key behaviors of olfaction in hydrothermal shrimp, which could provide an insight into their olfactory capacities: (1) grooming behavior; (2) attraction to environmental cues (food odors and fluid markers). We designed experiments at both deep-sea and atmospheric pressure to assess the behavior of the vent shrimp Rimicaris exoculata and Mirocaris fortunata , as well as of the coastal species Palaemon elegans and Palaemon serratus for comparison. Here, we show that hydrothermal shrimp groom their sensory appendages similarly to other crustaceans, but this does not clean the dense bacterial biofilm that covers the olfactory structures. These shrimp have previously been shown to possess functional sensory structures, and to detect the environmental olfactory signals tested, but we do not observe significant attraction behavior here. Only temperature, as a signature of vent fluids, clearly attracts vent shrimp and thus is confirmed to be a relevant signal for orientation in their environment.

Alvinocaridid shrimps are emblematic representatives of the deep hydrothermal vent fauna at the Mid-Atlantic Ridge. They are adapted to a mostly aphotic habitat with extreme physicochemical conditions in the vicinity of the hydrothermal fluid emissions. Here, we investigated the brain architecture of the vent shrimp Rimicaris exoculata to understand possible adaptations of its nervous system to the hydrothermal sensory landscape. Its brain is modified from the crustacean brain ground pattern by featuring relatively small visual and olfactory neuropils that contrast with well-developed higher integrative centers, the hemiellipsoid bodies. We propose that these structures in vent shrimps may fulfill functions in addition to higher order sensory processing and suggest a role in place memory. Our study promotes vent shrimps as fascinating models to gain insights into sensory adaptations to peculiar environmental conditions, and the evolutionary transformation of specific brain areas in Crustacea., Competing Interests: JM, JK, RM, MZ, JR, NM, TC, SH No competing interests declared, (© 2019, Machon et al.)

Assessing species thermal tolerance requires identification of their thermal strategies and evaluation of their ability to cope with temperature fluctuations. The mobilization of the molecular heat stress response (HSR), which is a proxy for the thermal tolerance, would be part of the strategy of species colonizing highly variable thermal environments. We here investigate multiple parameters of the HSR in the deep-sea vent shrimp Rimicaris exoculata that colonizes such environments. The set points of the HSR induction, compared to those of the coastal species Palaemonetes varians, clearly reflect a high thermotolerance in this species, while the HSR is proved to be rarely mobilized in the R. exoculata natural populations. Finally, the compilation of multiple parameters such as the upper thermal limit and several thresholds of the HSR, as well as thermal behavior observations, allows us to provide a more accurate picture of the combination and complementarity of strategies that can account for the overall thermal tolerance of the species.