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The optimal treatment of a severe hemodynamic instability from shock to cardiac arrest in late term pregnant women is subject to ongoing studies. However, there is an increasing evidence that early “separation” between the mother and the foetus may increase the restoration of the hemodynamic status and, in the cardiac arrest setting, it may raise the likelihood of a return of spontaneous circulation (ROSC) in the mother. This treatment, called Perimortem Cesarean Section (PMCS), is now termed as Resuscitative Hysterotomy (RH) to better address the issue of an early Cesarean section (C-section). This strategy is in contrast with the traditional treatment of cardiac arrest characterized by the maintenance of cardiopulmonary resuscitation (CPR) maneuvers without any emergent surgical intervention. We report the case of a prehospital perimortem delivery by Caesarean (C) section of a foetus at 36 weeks of gestation after the mother's traumatic cardiac arrest. Despite the negative outcome of the mother, the choice of performing a RH seems to represent up to date the most appropriate intervention to improve the outcome in both mother and foetus.

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MCrAlY coatings (where M stands for Co, Ni, or CoNi) are used as a single overlay coating or as bond coat for thermal barrier coating (TBC) systems. Low Pressure Plasma Spray (LPPS) or Vacuum Plasma Spray (VPS) MCrAlY coatings are considered nowadays the state of the art, nevertheless High Velocity Oxygen Fuel (HVOF) MCrAlY coating is gaining more and more importance due to its quality and to the possible cost reduction in comparison to the state of the art LPPS/VPS coatings. On the other hand the HVOF process tends to have a relatively low surface roughness, which hinders the possibility to act as bond coat for a TBC coating layer. In this work, a HVOF deposition process was developed to obtain a rough MCrAlY coating which can be used as bond coat for yttria partially stabilized zirconia (YPSZ) top coat. Developed parameters were used to apply a TBC system on a stage 2 blade. TBC sections on the same blade have successfully passed thermal fatigue testing according to the specification of an important OEM.

MCrAlY (where M is Ni, Co or NiCo) coatings are used as single overlay coating or as bond coat for thermal barrier coating (TBC) systems. Vacuum plasma spray (VPS) MCrAlY coatings are considered today to be a state of the art. Nevertheless, high velocity oxygen fuel (HVOF) sprayed MCrAlY coating is gaining in popularity due to its quality and cost effectiveness. On the other hand, HVOF process has some limits: It requires heavy sand blasting of the substrates to obtain an adequate base metal roughness for the good adhesion of the deposited MCrAlY coatings and this causes high interface pollution. Moreover, HVOF process allows to obtain relatively low surface roughness of the MCrAlY coatings, which leads to a poor adhesion of the ceramic yttria partially stabilized zirconia (YPSZ) top coat. Studies performed by the authors tried to resolve these two problems by providing an adequate pollution free interface between substrate and coating and a rough surface of the HVOF coating in order to be used as bond coat for overlaying TBC coating.This paper is the first part of two and addresses the development of a surface preparation method, in order to obtain a completely pollution free surface of the substrate with an adequate roughness to be coated afterwards with HVOF. A new surface preparation process, named eXclen , was set up and HVOF was used to apply MCrAlY coating on the prepared base material. Optical and electronic microscopies were used to evaluate the quality of the interface Base Material (BM)/Bond Coat (BC). It was possible to observe the absence not only of foreign entrapped particles, but also of any chemical contamination or alteration of both coating and substrate materials. The BM/BC interface quality and MCrAlY coating adhesion resulted to satisfy the Original Equipment Manufacturer (OEM) requirements.