Foreseeing postoperative pain in neurosurgical patients: pupillometry predicts postoperative pain ratings-an observational study.

Pupillary reflex dilation (PRD) is triggered by noxious stimuli and diminished by opioid administration. In the postoperative period, PRD has been shown to be correlated with pain reporting and a useful tool to guide opioid administration. In this study we assessed whether pupillary measurements taken before extubation were related with the patient's reported pain in the Post-Anesthesia Care Unit (PACU) using the Numerical Rating Scale (NRS). Our objective was to evaluate the correlation of PRD and pupillary variables measured intraoperatively with postoperative pain under the same opioid concentration. This was a prospective observational study of 26 neurosurgical patients undergoing general anesthesia exclusively with propofol and remifentanil. A portable infrared pupillometer was used to provide an objective measure of pupil size and PRD (using the Pupillary Pain Index) before extubation. Pain ratings were obtained from patients after recovery of consciousness, while remifentanil was maintained at 2 ng/mL. A significant correlation was observed between NRS scores and pre-extubation PPI (rS = 0.62; P = 0.002), as well as between NRS scores and pupil diameter before tetanic stimulation PPI (rS = 0.56, P = 0.006). We also found a negative correlation between pupil diameter and age (rS = - 0.42, P = 0.04). The statistically significant correlation between pre-extubation PPI scores and NRS scores, as well as between the pupillary diameter before tetanic stimulation and NRS scores suggest the possibility of titrating analgesia at the end of the intraoperative period based on individual responses. This could allow clinicians to identify the ideal remifentanil concentration for the postoperative period.

An Immunological Non-responder Human Immunodeficiency Virus/Hepatitis C Virus Coinfected Patient: Considerations About a Clinical Case.

Human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infections are two chronic viral infections that share the same mode of transmission, making HIV/HCV coinfection frequent. Highly active antiretroviral therapy (HAART) was a turning point in HIV treatment and has been shown to successfully restore immune function and reduce the frequency of opportunistic infections. Despite a virological response to HAART, a proportion of patients fail to achieve substantial immune recovery, as measured by peripheral CD4 cell counts. Herein, we present the case of a patient with HIV/HCV coinfection who did not achieve successful immune function restoration despite HIV suppression and HCV treatment. Our goal is to promote discussion. Despite considerable advances in the understanding of the impact of HCV on HIV disease progression, there are many individual variables that influence a patient's immune function. In addition, we consider hypogammaglobulinemia as a possible contributor. Further understanding and improvement of immune reconstitution in patients infected with HIV remain an important field of scientific research.

Primary Chest Wall Abscess Caused by Pseudomonas aeruginosa and Staphylococcus epidermidis.

Primary abscess of the thoracic wall is a very rare condition that occurs spontaneously due to hematogenous dissemination of bacterial, fungal, or mycobacterial pathogens, of which Mycobacterium tuberculosis is the most frequent agent. The authors describe a rare case of primary abscess of the thoracic wall. The patient presented with a painful, growing mass in the chest wall that later fistulized to the skin, draining a purulent exudate. Extensive analytical and imagiological workup was performed, showing no changes other than an expansive soft tissue formation extending from the skin surface and destructing the cartilage of the 7th right costal arch. Culture of the purulent exdudate identified Pseudomonas aeruginosa and Staphylococcus epidermidis. The patient improved under directed antibiotic treatment. The diagnosis of a primary abscess of the thoracic wall and the causative agents contribute to the rarity of this case.

Idiopathic Systemic Capillary Leak Syndrome: A Clinical Case.

Idiopathic systemic capillary leak syndrome (ISCLS) is a rare condition caused by the extravasation of intravascular fluids and proteins into the interstitial space due to increased vascular endothelium permeability. It is characterized by episodes of hypotension, hypoalbuminemia, and hemoconcentration with generalized edema. Its etiopathogenesis is unknown. However, it is associated with monoclonal gammopathy in more than 80% of cases. There is currently no targeted treatment, and the approach during a crisis is supportive, mainly to control blood pressure, maintain perfusion of vital organs, and prevent complications, such as acute pulmonary edema and organ failure due to ischemia, which are the primary causes of death. We present the case of a 72-year-old man with generalized edema and pleural, pericardial, and peritoneal effusions whose laboratory results showed hypoalbuminemia, hypoproteinemia, and immunoglobulin G kappa monoclonal gammopathy. Other etiologies for severe hypoalbuminemia with anasarca were excluded after an exhaustive complementary study, leading to the diagnosis of ISCLS associated with monoclonal gammopathy. The patient showed progressive clinical improvement with albumin and diuretic therapy. However, they were readmitted to the hospital due to hypotension with multiorgan dysfunction and died a few hours later.

McConnell in Shock.

The ideal approach to hemodynamically unstable patients requires the quick identification of the type of shock and its etiology. This can be a challenge in critically ill patients due to the limited information, the wide number of differential diagnosis and the need for fast intervention. Point-of-care ultrasound (POCUS) is a non-invasive, low-cost, real-time and reliable tool used to rapidly and accurately assess hemodynamically unstable patients at the bedside. It can support diagnosis, tailor therapy and guide further workup, especially in patients deemed too unstable to undergo other imaging studies. The authors describe the case of a patient in obstructive shock due to pulmonary embolism, in which McConnell sign was identified by bedside echocardiography, before lab tests and pulmonary computerized tomography angiogram results were obtained.

Non-Islet Cell Tumor Hypoglycemia Caused by Recurrent Pelvic Solitary Fibrous Tumor.

Non-islet cell tumor hypoglycemia is a rare paraneoplastic condition caused by an extra-pancreatic tumor. We report a rare case of hypoglycemia caused by a relapsing pelvic solitary fibrous tumor associated with Big-IGF-2 production. A 72-year-old woman was admitted to our hospital because of loss of consciousness and hypoglycemia. She had a history of ovarian solitary fibrous tumor, which has relapsed. From investigation, serum levels of insulin and C-peptide were suppressed; IGF-1 was slightly reduced and IGF-2 was within the normal range, but the IGF-2: IGF-1 ratio was elevated, indicating the presence of Big-IGF-2 secreting non-islet cell tumor. Contrast-enhanced computed tomography (CT) showed a large pelvic mass. She was then submitted to surgical resection of the mass, which histologically proved to be a solitary fibrous tumor. Three months later, she remains asymptomatic. Non-islet cell tumor hypoglycemia should be considered in the differential diagnosis of patients presenting with tumors and recurrent hypoglycemia.

Electrosynthesis of polydopamine-ethanolamine films for the development of immunosensing interfaces.

We report a straightforward and reproducible electrochemical approach to develop polydopamine-ethanolamine (ePDA-ETA) films to be used as immunosensing interfaces. ETA is strongly attached to polydopamine films during the potentiodynamic electropolymerization of dopamine. The great advantage of the electrochemical methods is to generate the oxidized species (quinones), which can readily react with ETA amine groups present in solution, with the subsequent incorporation of this molecule in the polymer. The presence of ETA and its effect on the electrosynthesis of polydopamine was accessed by cyclic voltammetry, ellipsometry, atomic force microscopy, FTIR and X-ray photoelectron spectroscopy. The adhesive and biocompatible films enable a facile protein linkage, are resilient to flow assays, and display intrinsic anti-fouling properties to block non-specific protein interactions, as monitored by real-time surface plasmon resonance, and confirmed by ellipsometry. Immunoglobulin G (IgG) and Anti-IgG were used in this work as model proteins for the affinity sensor. By using the one-step methodology (ePDA-ETA), the lower amount of immobilized biorecognition element, IgG, compared to that deposited on ePDA or on ETA post-modified film (ePDA/ETA), allied to the presence of ETA, improved the antibody-antigen affinity interaction. The great potential of the developed platform is its versatility to be used with any target biorecognition molecules, allowing both optical and electrochemical detection.

Synthesis, extrusion and rheological behaviour of PU/HA composites for biomedical applications.

Biostable polyurethane/hydroxyapatite (PU/HA) composites with potential application as bone replacement materials were synthesized in bulk and processed in a screw extruder. The polyurethanes (PU) were prepared by reacting an aliphatic diisocyanate, 4-methylene-bis-diisocyanate (MDI), with poly-(epsilon-caprolactone) (PCL) diols and polytetramethylene oxide (PTMO) of different molecular weights, extended with 1, 4-butanediol (BDO). Glass-transition temperatures were measured by differential scanning calorimetry (DSC). The specific PU groups were assessed by total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR). The effects of polymer chemistry and filler content on the rheological behaviour were studied by oscillatory rheometry. Polymers with larger chain lengths showed higher viscosity and, for identical chain lengths, polyether urethanes seem to have higher viscosities than polyester based urethanes. A lubricating effect was found for composites containing 50% weight of filler, whereas at higher filler contents a solid-like behaviour was measured. Polymer chemistry seems to be affected by ageing but not so by the presence of filler. Ageing is characterized by a decrease in the concentration of hydrogen bonds involving between urethane linkages.

Patterns of Hysteresis Between Induction and Emergence of Neuroanesthesia Are Present in Spinal and Intracranial Surgeries.

BACKGROUND: Recovery of consciousness is usually seen as a passive process, with emergence from anesthesia depicted as the inverse process of induction resulting from the elimination of anesthetic drugs from their central nervous system sites of action. However, that need not be the case. Recently it has been argued that we might encounter hysteresis to changes in the state of consciousness, known as neural inertia. This phenomenon has been debated in neuroanesthesia, as manipulation of the brain might further influence recovery of consciousness. The present study is aimed at assessing hysteresis between induction and emergence under propofol-opioid neuroanesthesia in humans using estimated propofol concentrations in both spinal and intracranial surgeries. METHODS: We identified the moments of loss (LOR) and recovery of responsiveness (ROR) in 21 craniotomies and 25 spinal surgeries. Propofol was given slowly until loss of responsiveness and stopped at the end of surgery. An opioid was present at induction and recovery. Propofol infused was recorded and plasma and effect-site concentrations were estimated using 2 pharmacokinetic models. Dose-response curves were generated. Estimated propofol plasma and effect-site concentrations were compared to assess hysteresis. RESULTS: Estimated propofol concentrations at LOR and ROR showed hysteresis. Whether for spinal or intracranial surgeries, the EC50 of propofol at which half of the patients entered and exited the state of responsiveness was significantly different. CONCLUSIONS: Hysteresis was observed between propofol concentrations at LOR and ROR, in both patients presenting for spinal and intracranial surgeries. Manipulation of the brain does not appear to change patterns of hysteresis, suggesting that neural inertia may occur in humans, in a way similar to that found in animal species. These findings justify performing a clinical study in patients using measured propofol concentrations to assess neural inertia.

Effect of Hemodynamic Changes in Plasma Propofol Concentrations Associated with Knee-Chest Position in Spinal Surgery: A Prospective Study.

BACKGROUND: Anesthesia induction and maintenance with propofol can be guided by target-controlled infusion (TCI) systems using pharmacokinetic (Pk) models. Physiological variables, such as changes in cardiac output (CO), can influence propofol pharmacokinetics. Knee-chest (KC) surgical positioning can result in CO changes. OBJECTIVES: This study aimed to evaluate the relationship between propofol plasma concentration prediction and CO changes after induction and KC positioning. METHODS: This two-phase prospective cohort study included 20 patients scheduled for spinal surgery. Two different TCI anesthesia protocols were administered after induction. In phase I (n = 9), the loss of consciousness (LOC) concentration was set as the propofol target concentration and CO changes following induction and KC positioning were quantified. In phase II (n = 11), based on data from phase I, two reductions in the propofol target concentration on the pump were applied after LOC and before KC positioning. Propofol plasma concentrations were measured at different moments in both phases: after induction and after KC positioning. RESULTS: Schnider Pk model showed a good performance in predicting propofol concentration after induction; however, after KC positioning, when a significant drop in CO occurred, the measured propofol concentrations were markedly underestimated. Intended reductions in the propofol target concentration did not attenuate HD changes. In the KC position, there was no correlation between the propofol concentration estimated by the Pk model and the measured concentration in plasma, as the latter was much higher (P = 0.013) while CO and BIS decreased significantly (P < 0.001 and P = 0.004, respectively). CONCLUSIONS: Our study showed that the measured propofol plasma concentrations during the KC position were significantly underestimated by the Schnider Pk model and were associated with significant CO decrease. When placing patients in the KC position, anesthesiologists must be aware of pharmacokinetic changes and, in addition to standard monitoring, the use of depth of anesthesia and cardiac output monitors may be considered in high-risk patients.

Effects of enrichment of refined olive oil with phenolic compounds from olive leaves.

The possibility of preparing olive oil, with the same nutritional value and stability characteristics found in virgin olive oil, by the enrichment of refined olive oil with olive leaf polyphenols was studied. To obtain antioxidant phenols similar to those found in virgin olive oil, these components were extracted from the leaves of several olive cultivars from the Northern region of Portugal, namely, Carrasca, Ripa, Negruche, Cordovil, Verdeal, Madural, and Bical cultivars, under several conditions. The concentration of a leaf extract required for addition to refined olive oil to obtain the same stability as virgin olive oil was determined. The extract from 1 kg of leaves was sufficient to fortify 50-320 L of refined olive oil to a similar stability as a virgin olive oil sample depending on the metal concentration of the oil, cultivar, and time of the year when the leaves were picked.

Influence of albumin on mineralization of PMMA-based/glass composites.

PURPOSE: The formation of a calcium phosphate layer on the surface of bone tissue engineering biomaterials is crucial for their integration in bone. Simulated biological fluids used to study the in vitro formation of those layers do not usually contain important organic components present in vivo-notably proteins. In this work the influence of bovine serum albumin on the mineralization process of poly(methylmethacrylate)-based composite was studied in vitro. METHODS: The effect of protein on calcium phosphate formation was followed by ion concentration analyses (ICP), x-ray diffraction (XRD), and scanning electron microscopy coupled with x-ray energy dispersive spectroscopy (SEM-EDS). RESULTS AND CONCLUSIONS: The results showed the precipitation of a calcium phosphate layer on the surface of composites immersed in SBF and SBFA. Further transformation and crystallization of this layer, initially amorphous, appears to be influenced by the presence of albumin.

New PMMA-co-EHA glass-filled composites for biomedical applications: Mechanical properties and bioactivity.

A bioactive glass of the 3CaO.P(2)O(5)-MgO-SiO(2) system was incorporated as a filler into poly(methylmethacrylate)-co-(ethylhexylacrylate) (PMMA-co-EHA) copolymer. The effect of filler proportion (0, 30, 40 and 50wt.%) on the bending properties was evaluated and a maximum flexural strength of 29MPa coupled with an elastic modulus of 1.1GPa was obtained at an intermediate filler concentration (30wt.%). These values are slightly higher than those usually reported for human cancellous bone. The in vitro bioactivity was assessed by determining the changes in surface morphology and composition after soaking in simulated body fluid (SBF, Kokubo solution). Inductively coupled plasma was used to trace the evolution of ionic concentrations in the SBF solution, namely Ca and P. X-ray diffraction and scanning electron microscopy confirmed the growth of spherical calcium phosphate aggregates on the surface of composites, indicating that the composites are potentially bioactive.

Titanium scaffolds for osteointegration: mechanical, in vitro and corrosion behaviour.

While titanium has been successful as an orthopaedic or dental implant material, performance problems still persist concerning implant-bone interfacial strength and mechanical modulus mismatch between metal and tissue. Porous structures are an advantageous alternative because the elastic modulus can be adjusted to match that of bone, thereby preventing bone resorption. Furthermore, to achieve early and strong stabilization theses structures may be coated with bioactive deposits, as hydroxyapatite. In the present work, titanium porous scaffolds were produced from TiH(2) slurry by a replication sponge reactive sintering method, and coated with hydroxyapatite by the sol-gel process. The obtained structures were microstructurally and mechanically characterized. Their in vitro bioactivity was investigated by soaking in a simulated body fluid (SBF). Electrochemical characterization was also performed in order to evaluate the effect of coating on corrosion resistance. The scaffolds exhibit a three-dimensionally interconnected porous structure that can be mechanically and morphologically compared to trabecular bone. Their in vitro bioactivity suggests potential for osseous integration. Coating also improves corrosion resistance in physiologically saline environment.

In situ synthesis of magnetite nanoparticles in carrageenan gels.

Magnetite nanoparticles have been successfully synthesized in the presence of carrageenan polysaccharides using an in situ coprecipitation method. Iron coordination to the sulfate groups of the polysaccharide was confirmed by FTIR. The polysaccharide type (kappa, iota, or lambda) and concentration have been varied and their effects on particle morphology and chemical stability of the resultant nanocomposite investigated. The presence of carrageenan induces the formation of smaller particles, compared to those formed in the absence of polymer, and their average size depends on the nature and concentration of the polysaccharide used. The chemical stability of magnetite nanoparticles toward oxidation was also seen to depend on biopolymer type with magnetite formed in iota-carrageenan showing the highest chemical stability. A general tendency toward lower stability is observed as the polysaccharide concentration is increased. It is suggested that magnetite chemical stability in the carrageenan composites is determined by a fine balance between particle size and gel strength, the latter determining oxygen diffusion rates through the medium.

O desenvolvimento do contrato psicológico orientado para desempenhos de elevado rendimento / Development of the psychological contract for performance oriented high income / Desarrollo del contrato psicológico para orientados a la ejecución de renta alta

O objectivo deste artigo consiste em demonstrar, conceptualmente, a relevância do contrato psicológico para a performance dos indivíduos nas organizações. O contrato de trabalho pode ser percepcionado de duas formas: o contrato formal, explicitado sob a forma de um contrato de trabalho escrito, e outra, informal e implícita, o contrato psicológico. Ambos envolvem direitos, obrigações e expectativas por parte do indivíduo e da organização. A literatura acentua a relevância do contrato psicológico transaccional, em detrimento de um contrato psicológico mais relacional, apesar dos contratos psicológicos assumidos pelos indivíduos se situarem, na realidade, num contínuo entre estes dois tipos de contratos. Neste estudo é apresentado um modelo conceptual explicativo do desenvolvimento dinâmico do contrato psicológico, orientado para performances de elevado rendimento. São analisados os contributos do contrato psicológico para o aprofundar de relações de compromisso, através de um maior envolvimento dos indivíduos no processo de definição de objectivos, e consequentes impactos ao nível da performance. O modelo propõe o estabelecimento de uma relação positiva e significante entre: confiança (cumprimento do acordo e justiça percebida), compromisso (objectivos) e performance (elevado rendimento).

The objective of this article consists of demonstrating, conceptually, the relevance of the psychological contract for the individuals’ performance in the organizations. The labor agreement can be perceived in two ways: the formal contract, explicitly under the form of a written labor agreement, and other, informal and implicit, the psychological contract. Both involve rights, obligations and expectations on the part of the individual and of the organization. The literature accentuates the relevance of the contract psychological transaction, to the detriment of a contract more psychological relational, in spite of the psychological contracts assumed by the individuals if they place, in the reality, in a continuous one among these two types of contracts. In this study an explanatory conceptual model of the dynamic development of the psychological contract is presented, guided for performances high income. They are analyzed the contributes of the psychological contract for deepening of commitment relationships, through a larger involvement of the individuals in the process of objectives definition, and consequent impacts at the level of the performance. The model proposes the establishment of a positive and significant relationship among: trust (I greet of the agreement and noticed justice), commitment (objectives) and performance (high income).

El propósito de este trabajo es demostrar la pertinencia conceptual del contrato psicológico para el desempeño de los individuos en las organizaciones. El contrato de trabajo puede ser percibido de dos maneras: el contrato formal, como se explica en la forma de un contrato de trabajo escrito, y otros informal e implícita, el contrato psicológico. Ambas implican los derechos, obligaciones y expectativas por parte del individuo y de la organización. La literatura destaca la importancia de la operación de contrato psicológico, más que un contrato psicológico más relacional, a pesar de los contratos psicológicos que hacen las personas se encuentran, en realidad, una continuidad entre estos dos tipos de contratos. Este estudio presenta un modelo conceptual que explica la evolución dinámica del contrato psicológico, el rendimiento de alto rendimiento orientada. Analiza las contribuciones del contrato psicológico para la profundización de las relaciones de compromiso a través de una mayor participación de individuos en el proceso de establecer metas, y el impacto resultante en el nivel de rendimiento. El modelo propone el establecimiento de una correlación positiva y significativa entre: la confianza (con el acuerdo y la justicia se percibe), el compromiso (objetivos) y rendimiento (ingresos altos).

O desenvolvimento do contrato psicológico orientado para desempenhos de elevado rendimento / Development of the psychological contract for performance oriented high income / Desarrollo del contrato psicológico para orientados a la ejecución de renta alta

O objectivo deste artigo consiste em demonstrar, conceptualmente, a relevância do contrato psicológico para a performance dos indivíduos nas organizações. O contrato de trabalho pode ser percepcionado de duas formas: o contrato formal, explicitado sob a forma de um contrato de trabalho escrito, e outra, informal e implícita, o contrato psicológico. Ambos envolvem direitos, obrigações e expectativas por parte do indivíduo e da organização. A literatura acentua a relevância do contrato psicológico transaccional, em detrimento de um contrato psicológico mais relacional, apesar dos contratos psicológicos assumidos pelos indivíduos se situarem, na realidade, num contínuo entre estes dois tipos de contratos. Neste estudo é apresentado um modelo conceptual explicativo do desenvolvimento dinâmico do contrato psicológico, orientado para performances de elevado rendimento. São analisados os contributos do contrato psicológico para o aprofundar de relações de compromisso, através de um maior envolvimento dos indivíduos no processo de definição de objectivos, e consequentes impactos ao nível da performance. O modelo propõe o estabelecimento de uma relação positiva e significante entre: confiança (cumprimento do acordo e justiça percebida), compromisso (objectivos) e performance (elevado rendimento).(AU)

The objective of this article consists of demonstrating, conceptually, the relevance of the psychological contract for the individuals’ performance in the organizations. The labor agreement can be perceived in two ways: the formal contract, explicitly under the form of a written labor agreement, and other, informal and implicit, the psychological contract. Both involve rights, obligations and expectations on the part of the individual and of the organization. The literature accentuates the relevance of the contract psychological transaction, to the detriment of a contract more psychological relational, in spite of the psychological contracts assumed by the individuals if they place, in the reality, in a continuous one among these two types of contracts. In this study an explanatory conceptual model of the dynamic development of the psychological contract is presented, guided for performances high income. They are analyzed the contributes of the psychological contract for deepening of commitment relationships, through a larger involvement of the individuals in the process of objectives definition, and consequent impacts at the level of the performance. The model proposes the establishment of a positive and significant relationship among: trust (I greet of the agreement and noticed justice), commitment (objectives) and performance (high income).(AU)

El propósito de este trabajo es demostrar la pertinencia conceptual del contrato psicológico para el desempeño de los individuos en las organizaciones. El contrato de trabajo puede ser percibido de dos maneras: el contrato formal, como se explica en la forma de un contrato de trabajo escrito, y otros informal e implícita, el contrato psicológico. Ambas implican los derechos, obligaciones y expectativas por parte del individuo y de la organización. La literatura destaca la importancia de la operación de contrato psicológico, más que un contrato psicológico más relacional, a pesar de los contratos psicológicos que hacen las personas se encuentran, en realidad, una continuidad entre estos dos tipos de contratos. Este estudio presenta un modelo conceptual que explica la evolución dinámica del contrato psicológico, el rendimiento de alto rendimiento orientada. Analiza las contribuciones del contrato psicológico para la profundización de las relaciones de compromiso a través de una mayor participación de individuos en el proceso de establecer metas, y el impacto resultante en el nivel de rendimiento. El modelo propone el establecimiento de una correlación positiva y significativa entre: la confianza (con el acuerdo y la justicia se percibe), el compromiso (objetivos) y rendimiento (ingresos altos).(AU)