¿Influyen las técnicas anestésicas en los resultados postoperatorios? Parte I

The influence of anesthetic technique on postoperative outcomes has opened a wide field of research in recent years.High-risk patients undergoing non-cardiac surgery are those who have higher incidence of postoperative complications and mortality. A proper definition of this group of patients should focus maximal efforts and resources to improve the results.In view of the significant reduction in postoperative mortality and morbidity in last 20 years, perioperative research should take into account new indicators to investigate the role of anesthetic techniques on postoperative outcomes. Studies focused on the evaluation of intermediate outcomes would probably discriminate better effectiveness differences between anesthetic techniques.We review some of the major controversies arising in the literature about the impact of anesthetic techniques on postoperative outcomes. We have grouped the impact of these techniques into 9 major investigation areas: mortality, cardiovascular complications, respiratory complications, postoperative cognitive dysfunction, chronic postoperative pain, cancer recurrence, postoperative nausea/vomiting, surgical outcomes and resources utilization.In this first part of the review, we discuss the basis on postoperative outcomes research, mortality, cardiovascular and respiratory complications.     

Differential effects of environmental enrichment and isolation housing on the hormonal and neurochemical responses to stress in the prefrontal cortex of the adult rat: relationship to working and emotional memories

The present study was designed to investigate the modulation of the stress responses by the environmental conditions and its putative neurobiological mechanisms. For that an integrative study on the effects of environmental enrichment and isolation housing on (1) the corticosterone, dopamine and acetylcholine responses to acute restraint stress in the prefrontal cortex (PFC) of the awake rat; (2) the mRNA levels of glucocorticoid receptors (GRs) in the PFC, and (3) the behavioral responses to stress, related to the PFC (habituation to a novel environment, spatial-working memory and inhibitory avoidance response) was performed. Male Wistar rats were maintained from 3 to 6 months of age in two different conditions: enriched (EC) or impoverished (IC). Animals were stereotaxically implanted with bilateral guide cannulae in the PFC to perform microdialysis experiments to evaluate the concentrations of corticosterone, dopamine and acetylcholine. EC animals showed lower increases of corticosterone and dopamine but not of acetylcholine than IC animals in the PFC in response to acute restraint stress (20 min). In the PFC, GR mRNA levels showed a trend towards an enhancement in EC animals. EC reduced the days to learn the spatial working memory task (radial-water maze). Spatial working memory, however, was not different between groups in either basal or stress conditions. Inhibitory avoidance response was reduced in EC rats. The changes produced by EC in the neurochemical, neuroendocrine and behavioral parameters evaluated suggest that EC rats could show a better coping during an acute stress challenge.     

Validation of the DYALS (dysphagia in amyotrophic lateral sclerosis) questionnaire for the evaluation of dysphagia in ALS patients

Neurological Sciences - Dysphagia is a common symptom during the trajectory of ALS, and it can significantly impact on the quality of life and prognosis of patients. Nowadays, no specific tool for...     

On the Production of Chitosan-Coated Polycaprolactone Nanoparticles in a Confined Impinging Jet Reactor

This work is focused on the synthesis of polycaprolactone nanoparticles, coated with chitosan, in a confined impinging jet reactor using the solvent displacement method. The role of the various reacting species was investigated, evidencing that a biocompatible polymer, for example, polycaprolactone, is required to support chitosan to obtain a monomodal particle size distribution, with low particle diameters. A surfactant is required to reduce the nanoparticle size (down to a mean diameter of about 260 nm) and obtain a positive zeta potential (about +31 mV), perfectly suitable for pharmaceutical applications. Different surfactants were tested, and Poloxamer 388 appeared to be preferable to polyvinyl alcohol. The effect of the concentration of Poloxamer 388 (in the range 0.5-5 mg mL^?1) and of chitosan (in the range 1.5-5 mg mL^?1) on both the mean particle size and zeta potential was also investigated, evidencing that chitosan concentration has the strongest effect on both parameters. Finally, the effect of solvent evaporation, quenching and feed flow rate was investigated, showing that the evaporation stage does not affect particle characteristics, quenching is required to avoid particle aggregation, and a minimum liquid flow rate of 80 mL min^?1 is required in the considered reactor to minimize the particle size.     

Enzymatic Block in the Synthesis of Gangliosides in DNA Virus-Transformed Tumorigenic Mouse Cell Lines

The ganglioside pattern of both SV40- and polyoma virus-transformed mouse cell lines differs from that of the parent cell lines or of cell lines that have transformed spontaneously in tissue culture. This is manifested by a dramatic decrease of gangliosides with an oligosaccharide chain larger than sialyllactose. Present investigations indicate that this change probably cannot be attributed to excessive catabolism of gangliosides, but is caused by impaired synthesis of tri- and tetrahexosyl gangliosides in the virus-transformed cell lines. We present evidence for the block of a required step for the biosynthesis of these ganglioside homologs. The block involves the enzyme catalyzing the transfer of N-acetylgalactosamine from uridine diphosphate N-acetylgalactosamine to hematosides (N-glycolylneuraminyl or N-acetylneuraminylgalactosylglucosyl ceramide). This well-defined enzymatic change opens the way for studies of the biochemical mechanism of the alteration of cell membranes which occurs after transformation by the tumorigenic DNA viruses polyoma and SV40.     

The retained antrum, its endoscopic diagnosis and clinical significance]

A 65-year-old man was admitted to our hospital with gastrointestinal bleeding. Seventeen years previously, he had a Billroth II procedure for a bleeding duodenal ulcer. A gastroscopy performed on admission showed a stomal ulcer with signs of recent haemorrhage. In the proximal end of the afferent loop, we saw retained gastric mucosa. Histological evaluation confirmed the existence of antrum gastric mucosa. Other diagnostic test for retained gastric antrum were normal. The different approaches in the diagnosis of retained gastric antrum, the importance of our findings and the clinic implications are discussed. We conclude that endoscopic management may be the first diagnostic method in the assessment of retained gastric antrum, and it's possible to find gastric mucosa in the proximal end of the afferent loop (antrum retained), without clinic manifestations.