Experience in anaesthetic management of non-cardiac surgery in patients with ventricular assist devices. / Experiencia en manejo anestésico para cirugía no cardiaca en pacientes con asistencias ventriculares.

Heart failure (HF) is a syndromic condition with a high incidence in current medicine. When the symptoms of HF progress, and become refractory, cardiac transplant is the best therapeutic option. However, due to the shortage of donors and the long waiting lists, many of those patients are candidates for implantation of ventricular assist devices as a bridge to the cardiac transplant, or when this is not an option, as a definitive therapy. A series of four clinical cases of patients with ventricular assist devices that required surgical intervention, is presented. Three of them were assisted with long-term care: two EXCOR (pulsatile and para-corporeal) and one HEARTWARE (non-pulsatile and intra-corporeal), and the last one with short-term assistance; CentriMag biventricular Levitronix. There is no significant literature on the peri-operative implications of these patients when they undergo urgent or scheduled surgery. The experience in our centre leads us to raise the need to determine a series of aspects: operation of each device, emphasising the correct placement of the cannulas during the surgery; the proper management of any medication, emphasising the importance of anticoagulant and anti-platelet therapies; the Pathophysiological changes at cardiopulmonary level due to the implantation of these devices; and the importance of the administration of a correct antibiotic therapy. Given the complexity of these cases, the limited experience in this field, and the few cases that exist in these situations, it is recommended to create protocols to ensure their proper management.

Quantitative assessment of the metabolic products of iron oxide nanoparticles to be used as iron supplements in cell cultures.

Iron nanoparticles (NPs) metabolism is directly associated to human health due to their use as anemia treatment and should be studied in detail in cells. Here we present a speciation strategy for the determination of the metabolic products of iron oxide nanoparticles coated by tartaric and adipic acids in enterocytes-like cell models (Caco-2 and HT-29). Such methodology is based on the use of SDS-modified reversed phase high performance liquid chromatography (HPLC) separation using inductively coupled plasma-mass spectrometry (ICP-MS) as Fe selective detector. Post-column isotope dilution analysis is used as quantification tool by adding 57Fe as isotopically enriched standard. To assess the separation capability of the method, two different iron nanostructures: iron sucrose nanoparticles -Venofer®- used as model suspension and iron tartrate/adipate-modified nanoparticles, both of about 4 nm (core size) were evaluated. The two nanostructures were injected into the system showing good peak profiles and quantitative elution recoveries (>80%) in both cases. In addition, both nanoparticulate fractions could be based-line separated from ionic iron species, which needed to be complexed with 1 mM citrate to elute from the column. Exposed cells up to 0.5 mM of iron tartrate/adipate-modified nanoparticles were specifically treated to extract the internalized NPs and the extracts examined using the proposed strategy. The obtained results revealed the presence of three different fractions corresponding to nanoparticle aggregates, dispersed nanoparticles and soluble iron respectively in a single chromatographic run. Quantitative experiments (column recoveries ranging from 60 to 80%) revealed the presence of the majority of the Fe in the nanoparticulated form (>75%) by summing up the dispersed and aggregate particles. Such experiments point out the high uptake and low solubilization rate of the tartrate/adipate NPs making these structures highly suitable as Fe supplements in oral anemia treatments.