Mixed-Model Curriculum for Nerve Block Education in Emergency Medicine Residency

Introduction With the rising opioid epidemic, there has been a push for multimodal pain management within the emergency department. Nerve blocks have been shown to be an effective pain management strategy for many conditions, with improved success when used with ultrasound. However, there is no generally accepted method for teaching residents how to perform nerve blocks. Materials and methods Seventeen residents from a single academic center were enrolled. The residents were surveyed pre-intervention regarding demographics, confidence, and use of nerve blocks. The residents then completed a mixed-model curriculum that included an electronic module (e-module) on three plane nerve blocks and a practice session. Three months later, residents were tested on their ability to independently perform the nerve blocks and resurveyed regarding confidence and use. Results Of the 56 residents in the program, 17 enrolled in the study; 16 participated in the first session, and nine participated in the second session. Each resident had < four ultrasound-guided nerve blocks prior to participation with a slight increase in the total number of nerve blocks after the sessions. Residents were able to perform, on average, 4.8 of seven tasks independently. Residents who completed the study reported feeling more confident in their ability to perform ultrasound-guided nerve blocks (p = 0.01) and to complete associated tasks (p < 0.01). Conclusion This educational model resulted in residents completing the majority of tasks independently with improved confidence in ultrasound-guided nerve blocks. There was only a slight increase in clinically performed blocks.

Ultrasound in Pregnancy

This article reviews the use of ultrasound in pregnancy pertinent to the emergency physician. The techniques for transabdominal and transvaginal studies are detailed including approaches to gestational dating. Diagnosis of ectopic pregnancy is reviewed focusing on the potential pitfalls: reliance on beta-human chorionic gonadotropin, pseudogestational sac, interstitial pregnancy, and heterotopic pregnancy. Techniques for the identification of placental issues and presenting parts during the second and third trimesters are reviewed. Ultrasound is a safe and effective tool for the experienced emergency physician and is integral to providing high-quality care to pregnant women.

POCUS for Diastolic Dysfunction: A Review of the Literature

Emergency and critical care physicians frequently encounter patients presenting with dyspnea and normal left ventricular systolic function who may benefit from early diastolic evaluation to determine acute patient management. The current American Society of Echocardiography Guidelines approach to diastolic evaluation is often impractical for point of care ultrasound (POCUS) evaluation, and few studies have evaluated the potential use of a simplified approach. This article reviews the literature on the use of a simplified diastolic evaluation to assist in determining acute patient management.

SWI as an Alternative to Contrast-Enhanced Imaging to Detect Acute MS Lesions

BACKGROUND AND PURPOSE

Acute inflammatory activity of MS lesions is traditionally assessed through contrast-enhanced T1-weighted MR images. The aim of our study was to determine whether a qualitative evaluation of non-contrast-enhanced SWI of new T2-hyperintense lesions might help distinguish acute and chronic lesions and whether it could be considered a possible alternative to gadolinium-based contrast agents for this purpose.

MATERIALS AND METHODS

Serial MR imaging studies from 55 patients with MS were reviewed to identify 169 new T2-hyperintense lesions. Two blinded neuroradiologists determined their signal pattern on SWI, considering 5 categories (hypointense rings, marked hypointensity, mild hypointensity, iso-/hyperintensity, indeterminate). Two different blinded neuroradiologists evaluated the presence or absence of enhancement in postcontrast T1-weighted images of the lesions. The Fisher exact test was used to determine whether each category of signal intensity on SWI was associated with gadolinium enhancement.

RESULTS

The presence of hypointense rings or marked hypointensity showed a strong association with the absence of gadolinium enhancement (P < .001), with a sensitivity of 93.0% and a specificity of 82.9%. The presence of mild hypointensity or isohyperintensity showed a strong association with the presence of gadolinium enhancement (P < .001), with a sensitivity of 68.3% and a specificity of 99.2%.

CONCLUSIONS

A qualitative analysis of the signal pattern on SWI of new T2-hyperintense MS lesions allows determining the likelihood that the lesions will enhance after administration of a gadolinium contrast agent, with high specificity albeit with a moderate sensitivity. While it cannot substitute for the use of contrast agent, it can be useful in some clinical settings in which the contrast agent cannot be administered.

Quantitative and Qualitative Analysis of Emergency Physician Performed Biparietal Diameter Estimate for Gestational Age

BACKGROUND

An accurate estimation of fetal gestational age is essential for the management of pregnant patients who present to the emergency department (ED). Point-of-care-ultrasound (POCUS) is an integral part of emergency medicine training and includes measurement of fetal gestational age by the biparietal diameter (BPD) method.

OBJECTIVES

In this study we performed a quantitative assessment of emergency physician (EP)-performed BPD estimate of gestational age to identify the percentage of studies performed in our department that had an estimated gestational age within 14 days of an adjusted radiological or obstetrical estimation.

METHODS

We performed a chart review of our ED ultrasound database and electronic medical records for cases where a BPD measurement was performed by an EP. We recorded the ED gestational age estimate in days and the radiological or obstetrical estimate of gestational age in days. We then calculated the difference in days between the two examinations. We used a normal binomial approximation to calculate 95% confidence intervals. A secondary analysis looked at the quality of the images based on measurement placement and the view obtained.

RESULTS

Seventy-four cases met eligibility criteria; of those, 67 (91%) had a gestational age estimation within 14 days of the adjusted radiological or obstetrical estimate (95% confidence interval 81-96%).

CONCLUSION

This study shows that EP-performed BPD measurements for gestational age are quantitatively accurate, with 91% of estimates within 14 days of a standard radiological or obstetrical estimation.

'Diagnosis of Boerhaave's Syndrome With Aid of Bedside Ultrasound

BACKGROUND

Boerhaave's syndrome is characterized by transmural rupture of the distal esophagus in the setting of increased intraluminal pressures combined with negative intrathoracic pressure. It is a rare condition with high mortality (20-50% mortality rate).

CASE REPORT

This is a case of a 47-year-old man who appeared acutely ill, presenting with shortness of breath, chest and abdominal pain, and diagnosed with Boerhaave's syndrome with the assistance of bedside ultrasound. WHY SHOULD AN EMERGENCY PHYSICIANS BE AWARE OF THIS?: Emergency physicians must have a heightened suspicion of this diagnosis in patients presenting with chest and abdominal pain and can use bedside ultrasound skills to aid with diagnosis.

Transesophageal Echocardiography Training of Emergency Physicians Through an E-Learning System

BACKGROUND

Transesophageal echocardiography (TEE) has been shown to be a powerful tool that emergency physicians can use to guide resuscitation efforts during cardiac arrest. Currently, there is no standardized curriculum to teach TEE to emergency physicians.

OBJECTIVE

We hypothesized that the use of a pilot training course combining interactive e-learning and hands-on simulation would increase the percentage of students achieving a score of ≥80% on a multiple-choice test of knowledge and increase self-reported comfort using TEE.

METHODS

We designed a 2.5-h TEE course for emergency physicians and medical intensive care unit fellows. Participants took a test of knowledge and a survey of comfort-both online-before, just after, and 4 weeks after taking the course. Survey responses measured participants self-reported comfort with using TEE in clinical practice. A normal binomial approximation was used to calculate the 95% confidence interval.

RESULTS

Of the 3 tests of knowledge, 15 participants completed all tests. Of the surveys of comfort, 31 participants completed the precourse survey, 32 completed the postcourse survey, and 19 completed the 4-week follow-up survey. The proportion of students scoring ≥80% improved from 40% on the precourse test to 80% on the postcourse test (95% confidence interval 1-79). The proportion of students indicating comfort with using TEE improved from 3% precourse to 53% postcourse (95% confidence interval 28-71).

CONCLUSIONS

A TEE training course resulted in a 50% increase in surveyed participants feeling comfortable using TEE in cardiac arrest and a 40% increase in participants scoring ≥80% on a test of knowledge.

Point-of-Care Teleultrasound: A Systematic Review

Background: Telemedicine and point-of-care ultrasound have merged to create a field known as teleultrasound (TUS). Real-time TUS involves the transmission of bedside ultrasound (US) images with direct feedback from an US expert. In this review, we summarize the current uses of real-time TUS and discuss its potential future uses. Methods: We performed a literature search (PubMed and EMBase) to assess articles related to real-time TUS. Data were extracted using a standardized collection form, and relevant articles were separated into feasibility or clinical studies. Results: Our search yielded 45 articles, with most of the reports taking place in resource-constrained settings. A large portion of the studies discussed the use of the focused assessment with sonography in trauma exam. Others included musculoskeletal, vascular, and echocardiography. Conclusion: Real-time TUS allows for rapid access to diagnostic imaging in various clinical settings. This technology is poised to expand with many uses on the horizon.

Example of antimicrobial stewardship program in a community hospital in Italy

BACKGROUND

Inappropriate use of antibiotics has caused the emergence of resistant strains of bacteria. The hospital of Alessandria, Italy, implemented an antimicrobial stewardship (AS) pilot program between 2013 and 2015 in the intensive care units (ICUs) and internal medicine departments of Casale Monferrato and Tortona. We aimed to describe the project, results at the end of the intervention, and its strengths and weaknesses.

METHODS

The protocol, designed by the local infection control committee, included three consecutive steps: local guidelines for empirical antibiotic therapy and list of prescription antibiotics with justification, monitoring of antibiotic consumption and antimicrobial resistance trend, and peer-to-peer audit sessions in the wards.

RESULTS

One thousand and eighty-five observations were made, corresponding to 850 patients admitted to the ICUs (16.7%) and internal medicine departments (83.3%). Appropriate antibiotic prescriptions increased by 6.4% between 2013 and 2015. The greatest improvement in appropriate prescriptions was observed for glycopeptides and fluoroquinolones (+17.4% and +16.2%, respectively). We reported 305 inappropriate prescriptions, with the most frequent errors being absence of an infectious process (33.3%), inadequate combination therapy (12.8%), and absence of microbiological investigations (8.5%). A reduced incidence of methicillin-resistant Staphylococcusaureus (MRSA) was also observed (p<0.0037).

CONCLUSIONS

Antimicrobial stewardship programs contribute to improving antibiotic prescription and can be implemented in small community hospitals. Narrower interventions, focused on a single disease or single antibiotic should be encouraged.

The Use of Transesophageal Echocardiography During Cardiac Arrest Resuscitation: A Literature Review

We propose that transesophageal echocardiography (TEE) can be used to guide cardiac arrest resuscitation. We undertook a literature search (Medline and EMBase) to assess articles on that topic. Our search yielded 55 articles falling into 3 categories: TEE used in operating rooms, TEE used in emergency departments, and TEE used in other settings. In many cases, TEE changed the direction of the resuscitation; however, it is unclear whether TEE changed patient-oriented outcomes, such as neurologically intact survival. Few adverse events related to TEE have been documented. There is growing evidence that physicians can learn to use TEE during resuscitations and apply the findings to clinical decisions.

Are Lipid Abnormalities Reliable Cardiovascular Risk Factors in Dialysis Patients?

Patients on chronic hemodialysis often present both hyperlipidemia and a high incidence of cardiovascular disease (CVD). Uremic hyperlipidemia has usually been regarded as one of the most important cardiovascular risk factors (CVRF) in these patients. In order to study whether the “uremia-induced” lipid abnormalities are actually associated with evidence of uremic CVD, and consequently may be considered reliable CVRF, 123 patients on chronic dialysis were reviewed for the presence of CVD and, at the same time, examined for their lipoprotein pattern and other clinical and biochemical variables.

Lipids and lipoproteins did not prove helpful in our study in identifying patients with CVD. Despite the fact that they had been on dialysis for a shorter time, CVD patients were significantly older and had higher blood pressure than patients without CVD. Our data suggest that the uremia-induced lipid abnormalities are not reliable markers of CVD in dialysis patients, and support the hypothesis that dialysis per se does not accelerate the atherosclerotic process in uremic patients

The Use of Tissue Plasminogen Activator in the Treatment of Wallenberg Syndrome Caused by Vertebral Artery Dissection

BACKGROUND

Acute cerebrovascular accident (CVA) is a devastating cause of patient morbidity and mortality. Up to 10% of acute CVAs in young patients are caused by dissection of the vertebral or carotid artery. Wallenberg syndrome results from a CVA in the vertebral or posterior inferior artery of the cerebellum and manifests as various degrees of cerebellar dysfunction. The administration of a thrombolytic medication has been recommended in the treatment of patients with stroke caused by cervical artery dissection. Surprisingly, there is scant literature on the use of this medication in the treatment of this condition.

CASE REPORT

We describe a 42-year-old man with the sudden onset of headache, left-sided neck pain, vomiting, nystagmus, and ataxia 1 h after completing a weightlifting routine. Computed tomography angiography revealed a grade IV left vertebral artery injury with a dissection flap extending distally and resulting in complete occlusion. Subsequent magnetic resonance imaging and angiography demonstrated acute left cerebellar and lateral medullary infarcts, consistent with Wallenberg syndrome. The patient was treated with tissue plasminogen activator, which failed to resolve his symptoms. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Emergency physicians frequently manage patients with acute CVAs. For select patients, the administration of tissue plasminogen activator can improve outcomes. However, the risk of major hemorrhage with this medication is significant. Cervical artery dissection is an important cause of acute stroke in young patients and is often missed on initial presentation. It is imperative for the emergency physician to consider acute cervical artery dissection as a cause of stroke and to be knowledgeable regarding the efficacy of thrombolytic medications for this condition.

THE DECADE OF THE RABiT (2005-15)

The RABiT (Rapid Automated Biodosimetry Tool) is a dedicated Robotic platform for the automation of cytogenetics-based biodosimetry assays. The RABiT was developed to fulfill the critical requirement for triage following a mass radiological or nuclear event. Starting from well-characterized and accepted assays we developed a custom robotic platform to automate them. We present here a brief historical overview of the RABiT program at Columbia University from its inception in 2005 until the RABiT was dismantled at the end of 2015. The main focus of this paper is to demonstrate how the biological assays drove development of the custom robotic systems and in turn new advances in commercial robotic platforms inspired small modifications in the assays to allow replacing customized robotics with 'off the shelf' systems. Currently, a second-generation, RABiT II, system at Columbia University, consisting of a PerkinElmer cell::explorer, was programmed to perform the RABiT assays and is undergoing testing and optimization studies.

In Vitro Effects of Aminobisphosphonates on Vγ9Vδ2 T Cell Activation and Differentiation

In this study we have evaluated the in vitro effects of four different aminobisphosphonates, alendronate, risedronate, neridronate and zoledronate, on Vγ9Vδ2 T cell activation and differentiation. All tested aminobisphosphonates induce an IL-2-dependent activation and expansion of Vγ9Vδ2 T lymphocytes in primary PBMC cultures of healthy donors. Most notably, they also determine a different distribution of Vγ9Vδ2 T cell subsets, with decrease of Tnaive and TCM cells and increase of TEM and TEMRA Vγ9Vδ2 cells, indicating that in vitro treatment with aminobisphosphonates induces Vγ9Vδ2 T lymphocytes to differentiate towards an effector/cytotoxic phenotype. Accordingly, Vγ9Vδ2 T lymphocytes cultured with aminobisphosphonates and IL-2 showed a major content of IFN-γ and acquired the ability to kill tumor target cells.

Effects of short-term manipulation of serum FFA concentrations on left ventricular energy metabolism and function in patients with heart failure: no association with circulating bio-markers of inflammation

BACKGROUND AND AIMS

We wanted to assess the effects of short-term changes in serum free fatty acids (FFAs) on left ventricular (LV) energy metabolism and function in patients with heart failure and whether they correlated with circulating markers of inflammation.

METHODS AND RESULTS

LV function and phosphocreatine (PCr)/ATP ratio were assessed using MR imaging (MRI) and 31P magnetic resonance spectroscopy (MRS) in 11 men with chronic heart failure in two experimental conditions 7 days apart. Study 1: MRI and 31P-MRS were performed before and 3-4 h after i.v. bolus + continuous heparin infusion titrated to achieve a serum FFA concentration of 1.20 mM. Study 2: The same protocol was performed before and after the oral administration of acipimox titrated to achieve a serum FFA concentration of 0.20 mM. Serum concentrations of IL6, TNF-α, PAI-1, resistin, visfatin and leptin were simultaneously assessed. Serum glucose and insulin concentrations were not different between studies. The PCr/ATP ratio (percent change from baseline: +6.0 ± 16.9 and -16.6 ± 16.1 % in Study 1 and Study 2, respectively; p = 0.005) and the LV ejection fraction (-1.5 ± 4.0 and -6.9 ± 6.3 % in Study 1 and Study 2, respectively; p = 0.044) were reduced during low FFA when compared to high FFA. Serum resistin was higher during Study 1 than in Study 2 (p < 0.05 repeated measures ANOVA); meanwhile, the other adipocytokines were not different.

CONCLUSION

FFA deprivation, but not excess, impaired LV energy metabolism and function within hours. Cautions should be used when sudden iatrogenic modulation of energy substrates may take place in vulnerable patients.

Bladder urothelial neoplasms in pediatric age: experience at three tertiary centers

INTRODUCTION

Urothelial bladder neoplasms (UBN) typically occur in patients in their sixth or seventh decade of life while they are infrequent in children and young adults. They occur in 0.1-0.4% of the population in the first two decades of life. Their management is controversial and paediatric guidelines are currently unavailable.

OBJECTIVE

To further expound the available data on the outcome of patients younger than 18 year old diagnosed with UBN.

STUDY DESIGN

We retrospectively reviewed the files of all the consecutive paediatric patients with UBN treated in three tertiary paediatric urology units from January 1999 to July 2013. Lesions were classified according to the 2004 WHO/ISUP criteria as urothelial papillomas (UP), papillary urothelial neoplasm of low malignant potential (PUNLMP), low-grade urothelial carcinoma (LGUC), and high-grade urothelial carcinoma (HGUC).

RESULTS

The table shows the results. Management after TURB varied among centres. One centre recommended only follow-up US at increasing intervals whereas another follow-up US plus urine cytologies and endoscopies, every three months in the first year, and at increasing intervals thereafter. After a median follow-up of 5 years (range 9 months-14.5 years), none of the patients showed disease recurrence or progression.

DISCUSSION

UBN is an uncommon condition in children and adolescents and, unlike in adults, its incidence, follow-up and outcome still controversial. Paediatric guidelines are currently lacking and management varies among centres. Gross painless haematuria is the most common presenting symptom. Therefore, this symptom should never be underestimated. US is generally the first investigation and additional imaging seems unnecessary. TURB often allows for complete resection. Lesions are generally solitary, non-muscle invasive, and low-grade (mainly UP and PUNLMP). Ideal follow-up protocol is the most controversial point. Reportedly, recurrence or progression during follow-up is uncommon in patients under 20 years, recurrence rate 7% and a single case of progression reported so far. Accordingly, a follow-up mainly based on serial US might be considered in this age group compared to adults where also serial endoscopies and urine cytologies are recommended. In the selection of the follow-up investigations, it should also be taken into consideration that urine cytology has a low sensibility in the detection of low-grade lesions while cystoscopy in young patients requires a general anaesthesia and hospitalization, and carries an increased risk of urethral manipulation.

CONCLUSION

UBN is a rare condition in children. Ultrasound is generally accurate in order to visualize the lesion, and TURB can treat the condition. Lesions are generally low-grade and non-muscle invasive, but high-grade lesions can also be detected. In present series, after TURB, follow-up US monitoring at increasing intervals was used at all centres, follow-up cystoscopies were added in two centres, but with different schedules. Urine cytologies were considered only at one centre. After a median follow-up of 5 years (range 9 months-14.5 years), none of the patients showed recurrence or progression of the disease.

Incretins or anti-incretins? A new model for the "entero-pancreatic axis"

The role of incretins in glucose homeostasis is well known. Yet, in recent years, the sustained weight loss and rapid glycemic control following bariatric surgery has challenged our understanding of the intestinal-pancreatic interaction. This in turn led to the introduction of metabolic surgery, an innovative medical discipline in which a surgical manipulation of the gastrointestinal tract (e. g., through a Roux-en-Y gastric bypass, RYGB, or Bilio-Pancreatic-Diversion, BPD) yields a sustained remission of diabetes mellitus. The pathophysiological background of this metabolic effect is, amongst other things, based on the anti-incretin theory. This theory postulates that in addition to the well-known incretin effect, nutrient passage through the GI-tract could also activate negative feedback mechanisms (anti-incretins) to balance the effects of incretins and other postprandial glucose-lowering mechanisms (i. e., suppression of ghrelin, glucagon, and hepatic glucose production via activation of nutrient sensing). This in turn prevents postprandial hyperinsulinemic hypoglycemia. The bypass of the duodenum, the entire jejunum and the first portion of the ileum by BPD induce normalization of peripheral insulin sensitivity, while the bypass of a shorter intestinal tract by RYGB mainly improves the hepatic insulin sensitivity. In addition, RYGB greatly increases insulin secretion. Therefore, metabolic surgery highlights the important role of the small intestine in glucose homeostasis, while until few years ago, it was only the pancreas and the liver that were thought to represent the regulatory organs for glucose disposal.

Thermoplastic Foams from Zein and Gelatin

The aim of this study was to characterize the foaming of natural proteins as thermoplastic polymers. In particular, two proteins, one of vegetal origin, zein, and one of animal origin, gelatin, were processed to achieve thermoplastic polymers, and subsequently foamed by a gas foaming batch process. The effects of suitable plasticizing additives and melt-mixing process on the thermal and mechanical properties of the thermoplasticized proteins were evaluated to assess the thermoplastic characteristics of these materials. Furthermore, selected protein/plasticizers systems were foamed with mixtures of CO2 and N2 as blowing agents, in a batch foaming apparatus, at different temperatures, pressures and pressure drop rates, to evaluate the processing window and the final properties of the foams. Foams with densities of 0.1 g/cm3 and morphologies characterized by uniform distributions of cells with 10 μm diameters were obtained. Results indicated the suitability of zein and gelatin for being processed with classical thermoplastic processing technologies including melt mixing and foaming and their potentials as biodegradable polymers.

Tuning the microstructure and biodegradation of three-phase scaffolds for bone regeneration made of PCL, Zein, and HA

The aim of this study has been the design of novel multi-phase porous scaffolds with bi-modal pore size distributions and controlled biodegradation rate for bone tissue engineering (bTE), via a gas foaming—leaching approach. Poly( ε-caprolactone) (PCL) has been melt mixed with thermoplastic zein (TZ) and hydroxyapatite particle, to prepare multi-phase PCL—TZ and PCL—TZ—HA composites suitable to be further processed for the fabrication of 3D porous scaffolds. To this aim, these systems have been gas foamed by using CO2 as blowing agent and, subsequently, soaked in H2O to leach out the plasticizer from the TZ. This combined process allows the formation of an interpenetrated micro- and macro-porosity network within the samples. The effect of the different formulations on the micro-structural properties and in vitro biodegradation of the scaffolds has been investigated, and the results correlated to the mechanisms involved in the formation of the bi-modal pore structure. Results demonstrated that the multi-phase nature of the biomaterials prepared as well as their composition significantly affect the micro-structural properties and biodegradation rate of the scaffolds. The optimal selection of the processing conditions may allow for the design of multi-phase 3D porous scaffolds suitable for bTE.

Experimental validation of a reach-and grasp optimization algorithm inspired to human arm-hand control

Taking inspiration from neurophysiological studies on synergies in the human grasping action, this paper tries to demonstrate that it is possible to find a general rule for performing a stable, human-like cylindrical grasp with a robotic hand. To this purpose, the theoretical formulation and the experimental validation of a reach-and-grasp algorithm for determining the optimal hand position and the optimal finger configuration for grasping a cylindrical object with known features are presented. The proposed algorithm is based on the minimization of an objective function expressed by the sum of the distances of the hand joints from the object surface. Algorithm effectiveness has preliminarily been tested by means of simulation trials. Experimental trials on a real arm-hand robotic system have then been carried out in order to validate the approach and evaluate algorithm performance.

NYHA Class II subgrouping: correlation with left ventricular dysfunction questionnaire (LVD-36) and ejection fraction

AIM

NYHA classification divides into four classes. Although subjective and lacking of standardization, NYHA class II is in clinical practice often further subgrouped in IIA and IIB, where IIA class can be defined as dyspnea after running or climbing ≥ 2 ramps of stairs, and IIB class as dyspnea after fast walking or climbing 2 ramps of stairs. Validation of NYHA IIA and IIB sub-grouping was performed with left ventricular dysfunction questionnaire (LVD-36) results and echocardiographic left ventricular ejection fraction.

METHODS

The study includes a total of 127 patients with both systolic and diastolic heart failure (mean age 65 ± 17, range 38-85 years). Sixteen patients were in NYHA class I, 81 patients in NYHA class II (45 in class IIA and 36 in class IIB) and 30 in class III.

RESULTS

In class IIA patients' mean age was 64 ± 9 years, LVD-36 score 31.79 ± 14.06, EF 43 ± 10% (P = ns, P<0.001 and P=ns, respectively, vs. class I patients). In class IIB patients' mean age was 67 ± 10 years, LVD-36 score 48.90 ± 15.51, EF 39 ± 12% (P = ns, P < 0.0001 and P = ns, respectively, vs. IIA patients). In class III patients' mean age was 65 ± 11 years, LVD-36 score 65.17 ± 16.35, EF 32.77 ± 12.91% (P = ns, P < 0.01 and P = ns, respectively, compared with class IIB).

CONCLUSION

NYHA class II sub-grouping appears an accurate method of classification and could represent a further useful tool in monitoring functional capacity of heart failure patients. NYHA class II sub-grouping correlates well with patients functional impairment and can therefore be implemented as an accurate method to better characterize heart failure patients.

Design of porous polymeric scaffolds by gas foaming of heterogeneous blends

One of the challenges in tissue engineering scaffold design is the realization of structures with a pre-defined multi-scaled porous network. Along this line, this study aimed at the design of porous scaffolds with controlled porosity and pore size distribution from blends of poly(epsilon-caprolactone) (PCL) and thermoplastic gelatin (TG), a thermoplastic natural material obtained by de novo thermoplasticization of gelatin. PCL/TG blends with composition in the range from 40/60 to 60/40 (w/w) were prepared by melt mixing process. The multi-phase microstructures of these blends were analyzed by scanning electron microscopy and dynamic mechanical analysis. Furthermore, in order to prepare open porous scaffolds for cell culture and tissue replacement, the TG and PCL were selectively extracted from the blends by the appropriate combination of solvent and extraction parameters. Finally, with the proposed combination of gas foaming and selective polymer extraction technologies, PCL and TG porous materials with multi-scaled and highly interconnected porosities were designed as novel scaffolds for new-tissue regeneration.

Engineered mu-bimodal poly(epsilon-caprolactone) porous scaffold for enhanced hMSC colonization and proliferation

The use of scaffold-based strategies in the regeneration of biological tissues requires that the design of the microarchitecture of the scaffold satisfy key microstructural and biological requirements. Here, we examined the ability of a porous poly(epsilon-caprolactone) (PCL) scaffold with novel bimodal-micron scale (mu-bimodal) porous architecture to promote and guide the in vitro adhesion, proliferation and three-dimensional (3-D) colonization of human mesenchymal stem cells (hMSCs). The mu-bimodal PCL scaffold was prepared by a combination of gas foaming (GF) and selective polymer extraction (PE) from co-continuous blends. The microarchitectural properties of the scaffold, in particular its morphology, porosity distribution and mechanical compression properties, were analyzed and correlated with the results of the in vitro cell-scaffold interaction study, carried out for 21days under static conditions. Alamar Blue assay, scanning electron microscopy, confocal laser scanning microscopy and histological analyses were performed to assess hMSC adhesion, proliferation and 3-D colonization. The results showed that the combined GF-PE technique allowed the preparation of PCL scaffold with a unique multiscaled and highly interconnected microarchitecture that was characterized by mechanical properties suitable for load-bearing applications. Study of the cell-scaffold interaction also demonstrated the ability of the scaffold to support hMSC adhesion and proliferation, as well as the possibility to promote and guide 3-D cell colonization by appropriately designing the microarchitectural features of the scaffold.