Complications During Inter-Hospital Transfer of Patients with Acute Ischemic Stroke for Endovascular Therapy.

Purpose: Few data are available on complications occurring during inter-hospital transfer from a primary stroke center (PSC) to a comprehensive stroke center (CSC) for endovascular treatment (EVT) after large vessel occlusion (LVO). Therefore, we prospectively studied data from consecutive patients transferred from our PSC to the next CSC during 4 years to determine the incidence and risk factors of complications during transfer. Methods: This observational, single-center study included consecutive patients transferred from January 1, 2015 to December 31, 2018. During inter-hospital transfer, all medical incidents were systematically recorded. A new complete clinical examination was performed on arrival at the CSC. Results: Among the 253 patients transferred to the CSC during the study period, 68 (26.9%) had one or more complications. In 11 patients (4.3%) these were life-threatening and required emergency intervention by a physician. Baseline characteristics were not different between patients with and without complications, except for the LVO location. Specifically, basilar artery (BA) occlusion was strongly associated with complications during the transport (p < 0.0005). Conclusion: Complications occurred in 26.9% of patients during transfer. Only BA occlusion could predict complication during transfer. Future studies should identify variables to help stratifying patients at high and low risk of complications during transportation.

Which Patients Require Physician-Led Inter-Hospital Transport in View of Endovascular Therapy?

INTRODUCTION: The current guidelines advocate the implementation of stroke networks to organize endovascular treatment (ET) for patients with acute ischemic stroke due to large vessel occlusion (LVO) after transfer from a Primary Stroke Centre (PSC) to a Comprehensive Stroke Centre (CSC). In France and in many other countries around the world, these transfers are carried out by a physician-led mobile medical team. However, with the recent broadening of ET indications, their availability is becoming more and more critical. Here, we retrospectively analysed data of patients transferred from a PSC to a CSC for potential ET to identify predictive factors of major complications (MC) at departure and during transport that absolutely require the presence of a physician during interhospital transfer. METHODS: This observational, single-centre study included patients with evidence of intracranial LVO transferred for ET from Perpignan to a 156 km-distant CSC between January 1, 2015 and -December 31, 2018. We compared 2 groups: MC group (patients who required emergency intervention by the medical team due to life-threatening complications, including need of mechanical ventilation at departure) and non-MC group (all other patients who experienced no or only minor complications that could be managed by the emergency paramedics alone). RESULTS: Among the 253 patients who were transferred to the CSC, 185 (73.1%) had no complication, 57 (22.6%) minor complications, and 11 (4.3%) had MC. In multivariate analysis, MC was associated with basilar artery (BA) occlusion (p < 0.0001), initial National Institute of Health Stroke Scale (NIHSS) score >22 (p < 0.005), and history of atrial fibrillation (p < 0.04). Among the 168 patients treated with intravenous thrombolysis (IVT), only 1 patient (0.6%) had MC due to an IVT-related adverse event during transfer. CONCLUSIONS: Physician-led inter-hospital transports are warranted for patients with BA occlusion, initial NIHSS score >22, or history of atrial fibrillation. For the other patients, transfer without a physician may be considered, even if treated with IVT.

Mechanical Recanalization after Transfer from a Distant Primary Stroke Center: Effectiveness and Future Directions.

INTRODUCTION: Little is known about the effectiveness of endovascular treatment (EVT) in patients with acute ischemic stroke (AIS) due to large vessel occlusion (LVO) admitted to a primary stroke center (PSC). The aim of this study was to assess EVT effectiveness after transfer from a PSC to a distant (156 km apart; 1.5 hour by car) comprehensive stroke center (CSC), and to discuss perspectives to improve access to EVT, if indicated. PATIENTS AND METHOD: Analysis of the data collected in a 6-year prospective registry of patients admitted to a PSC for AIS due to LVO and selected for transfer to a distant CSC for EVT. The rate of transfer, futile transfer, EVT, reperfusion (thrombolysis in cerebral infarction score ≥2b-3), and relevant time measures were determined. RESULTS: Among the 529 patients eligible, 278 (52.6%) were transferred and 153 received EVT (55% of transferred patients) followed by reperfusion in 115 (overall reperfusion rate: 21.7%). Median times (interquartile range) were: 90 minutes (76-110) for PSC-door-in to PSC-door-out, 88 minutes (65-104) for PSC-door-out to CSC-door-in, 262 minutes (239-316) for PSC-imaging to reperfusion, and 393 minutes (332-454) for symptom onset to reperfusion. At 3 months, rates of favorable outcome (modified Rankin Scale 0-2) were not significantly different between patients eligible for EVT (42.4%), transferred patients (49.1%) and patients who underwent EVT (34.1%). DISCUSSION AND CONCLUSIONS: Our study suggests that transfer to a distant CSC is associated with reduced access to early EVT. These results argue in favor of on-site EVT at high volume PSCs that are distant from the CSC.

Methionine Sulfoxide Reductase-B3 Risk Allele Implicated in Alzheimer's Disease Associates with Increased Odds for Brain Infarcts.

Genome-wide association studies identified a single nucleotide polymorphism (SNP) in the MSRB3 gene encoding Methionine Sulfoxide Reductase-B3 (MsrB3) to be associated with the risk for low hippocampal volume and late onset Alzheimer's disease (AD). Subsequently, we identified AD-associated abnormal patterns of neuronal and vascular MsrB3 expression in postmortem hippocampi. The present study investigated the relationship between the MSRB3 SNP rs61921502, G (minor/risk allele) and MRI measures of brain injury including total brain volume, hippocampal volume, and white matter hyperintensities using linear regression models; the presence of brain infarcts using logistic regression models; and the incidence of stroke, dementia, and AD using Cox proportional hazards models in 2,038 Framingham Heart Study Offspring participants with MRI administered close to examination cycle 7 (1998-2001). Participants with neurological conditions that impede evaluation of vascular pathology by MRI, i.e., brain tumors, multiple sclerosis, and major head trauma, were excluded from the study. When adjusted for age and age squared at MRI exam, sex, and presence of Apolipoproteinɛ4 allele (APOE4), individuals with MSRB3 rs61921502 minor allele had increased odds for brain infarcts on MRI compared to those with no minor allele. However, in stratified analyses, MSRB3 rs61921502 minor allele was significantly associated with increased odds for MRI brain infarcts only in the absence of APOE4.

Immunohistochemical Analysis of Activin Receptor-Like Kinase 1 (ACVRL1/ALK1) Expression in the Rat and Human Hippocampus: Decline in CA3 During Progression of Alzheimer's Disease.

The pathophysiology of Alzheimer's disease (AD) includes signaling defects mediated by the transforming growth factor ß-bone morphogenetic protein-growth and differentiation factor (TGFß-BMP-GDF) family of proteins. In animal models of AD, administration of BMP9/GDF2 improves memory and reduces amyloidosis. The best characterized type I receptor of BMP9 is ALK1. We characterized ALK1 expression in the hippocampus using immunohistochemistry. In the rat, ALK1 immunoreactivity was found in CA pyramidal neurons, most frequently and robustly in the CA2 and CA3 fields. In addition, there were sporadic ALK1-immunoreactive cells in the stratum oriens, mainly in CA1. The ALK1 expression pattern in human hippocampus was similar to that of rat. Pyramidal neurons within the CA2, CA3, and CA4 were strongly ALK1-immunoreactive in hippocampi of cognitively intact subjects with no neurofibrillary tangles. ALK1 signal was found in the axons of alveus and fimbria, and in the neuropil across CA fields. Relatively strongest ALK1 neuropil signal was observed in CA1 where pyramidal neurons were occasionally ALK1-immunoractive. As in the rat, horizontally oriented neurons in the stratum oriens of CA1 were both ALK1- and GAD67-immunoreactive. Analysis of ALK1 immunoreactivity across stages of AD pathology revealed that disease progression was characterized by overall reduction of the ALK1 signal in CA3 in advanced, but not early, stages of AD. These data suggest that the CA3 pyramidal neurons may remain responsive to the ALK1 ligands, e.g., BMP9, during initial stages of AD and that ALK1 may constitute a therapeutic target in early and moderate AD.

Methionine Sulfoxide Reductase-B3 (MsrB3) Protein Associates with Synaptic Vesicles and its Expression Changes in the Hippocampi of Alzheimer's Disease Patients.

Genome-wide association studies (GWAS) identified susceptibility loci associated with decreased hippocampal volume, and found hippocampal subfield-specific effects at MSRB3 (methionine sulfoxide reductase-B3). The MSRB3 locus was also linked to increased risk for late onset Alzheimer's disease (AD). In this study, we uncovered novel sites of MsrB3 expression in CA pyramidal layer and arteriolar walls by using automated immunohistochemistry on hippocampal sections from 23 individuals accompanied by neuropathology reports and clinical dementia rating scores. Controls, cognitively intact subjects with no hippocampal neurofibrillary tangles, exhibited MsrB3 signal as distinct but rare puncta in CA1 pyramidal neuronal somata. In CA3, however, MsrB3-immunoreactivity was strongest in the neuropil of the pyramidal layer. These patterns were replicated in rodent hippocampi where ultrastructural and immunohistofluorescence analysis revealed MsrB3 signal associated with synaptic vesicles and colocalized with mossy fiber terminals. In AD subjects, the number of CA1 pyramidal neurons with frequent, rather than rare, MsrB3-immunoreactive somatic puncta increased in comparison to controls. This change in CA1 phenotype correlated with the occurrence of AD pathological hallmarks. Moreover, the intensity of MsrB3 signal in the neuropil of CA3 pyramidal layer correlated with the signal pattern in neurons of CA1 pyramidal layer that was characteristic of cognitively intact individuals. Finally, MsrB3 signal in the arteriolar walls in the hippocampal white matter decreased in AD patients. This characterization of GWAS-implicated MSRB3 protein expression in human hippocampus suggests that patterns of neuronal and vascular MsrB3 protein expression reflect or underlie pathology associated with AD.

Partial extracorporeal carbon dioxide removal using a standard continuous renal replacement therapy device: a preliminary study.

To test the feasibility, safety, and efficacy of partial extracorporeal CO2 removal (PECCO2R) using a standard continuous renal replacement (CRRT) device with a pediatric oxygenation membrane introduced into the circuit in a serial manner. In this retrospective single-center study, we have studied mechanically ventilated patients with persistent significant respiratory acidosis and acute renal failure requiring ongoing CRRT. Sixteen patients were treated with our PECCO2R device. PaCO2 and arterial pH were measured before as well as at 6 and 12 hours after PECCO2R implementation. Hemodynamic parameters were continuously monitored. Our PECCO2R system was efficient to significantly reduce PaCO2 and increase arterial pH. The median PaCO2 before treatment was 77 mm Hg (59-112) with a median reduction of 24 mm Hg after 6 hours and 30 mm Hg after 12 hours (31% and 39%, respectively). The median pH increase was 0.16 at 6 hours and 0.23 at 12 hours. Partial extracorporeal CO2 removal treatment had no effect on oxygenation. No complication was observed. Our PECCO2R approach based on the simple introduction of a pediatric extracorporeal membrane oxygenation membrane into the circuit of a standard CRRT device is easy to implement, safe, and efficient to improve respiratory acidosis.

Determinants of recovery from severe posterior reversible encephalopathy syndrome.

OBJECTIVE: Few outcome data are available about posterior reversible encephalopathy syndrome (PRES). We studied 90-day functional outcomes and their determinants in patients with severe PRES. DESIGN: 70 patients with severe PRES admitted to 24 ICUs in 2001-2010 were included in a retrospective cohort study. The main outcome measure was a Glasgow Outcome Scale (GOS) of 5 (good recovery) on day 90. MAIN RESULTS: Consciousness impairment was the most common clinical sign, occurring in 66 (94%) patients. Clinical seizures occurred in 57 (81%) patients. Median mean arterial pressure was 122 (105-143) mmHg on scene. Cerebral imaging abnormalities were bilateral (93%) and predominated in the parietal (93%) and occipital (86%) white matter. Median number of brain areas involved was 4 (3-5). Imaging abnormalities resolved in 43 (88%) patients. Ischaemic and/or haemorrhagic complications occurred in 7 (14%) patients. The most common causes were drug toxicity (44%) and hypertensive encephalopathy (41%). On day 90, 11 (16%) patients had died, 26 (37%) had marked functional impairments (GOS, 2 to 4), and 33 (56%) had a good recovery (GOS, 5). Factors independently associated with GOS<5 were highest glycaemia on day 1 (OR, 1.22; 95%CI, 1.02-1.45, p = 0.03) and time to causative-factor control (OR, 3.3; 95%CI, 1.04-10.46, p = 0.04), whereas GOS = 5 was associated with toxaemia of pregnancy (preeclampsia/eclampsia) (OR, 0.06; 95%CI, 0.01-0.38, p = 0.003). CONCLUSIONS: By day 90 after admission for severe PRES, 44% of survivors had severe functional impairments. Highest glycaemia on day 1 and time to causative-factor control were strong early predictors of outcomes, suggesting areas for improvement.

An evaluation of the role of gene expression in the prediction and diagnosis of ventilator-associated pneumonia.

BACKGROUND: The SepsiChip project explored transcriptional modulation associated with ventilator-associated pneumonia (VAP) in patients admitted to the intensive care unit for trauma. Genome-wide expression analysis may help to identify potential diagnostic markers for diseases. The current study examined the changes in blood transcriptome during VAP. METHODS: The authors prospectively included 165 trauma patients, and 41 developed VAP. Whole blood samples were collected at admission and at VAP. To predict VAP, the admission samples were compared by microarray in patients who did or did not develop VAP. To identify diagnosis markers, paired samples of 35 patients who developed VAP were analyzed. Using NanoString (Seattle, WA), the results were confirmed in the patients who developed VAP. Trauma patients who did not develop VAP served as controls to eliminate a time effect. RESULTS: The injury severity scores of the patients who did or did not develop VAP were 36 and 29, respectively. No predictive biomarker was identified. For patients who developed VAP, a transcriptional signature was identified between the two sampling times. However, this signature was a generalized pattern related to trauma, independent of the infectious process. Genes involved in the proinflammatory response were down-regulated in the patients who developed VAP, but this difference was not statistically significant. CONCLUSIONS: In contrast to clinical assessment, transcriptional analysis of whole blood samples cannot predict or diagnose VAP in trauma patients. Differentiating infection from inflammation seems challenging.

Epithelium expression and function of retinoid receptors in asthma.

Abnormal epithelial repair to damage participates in airway remodeling in asthma by the paracrine regulation of mesenchymal cell functions. Retinoids control epithelial functions through nuclear retinoic acid receptor (RAR) and retinoid X receptor (RXR) activation, yet their expression and contribution to epithelial repair and to airway remodeling in asthma are unknown. We determined the plasma levels of retinol and the immunohistochemical expression of retinoid receptors in damaged and repaired bronchial epithelium from 9 control subjects, 10 subjects with intermittent asthma, 8 subjects with mild-to-moderate asthma, and 8 subjects with severe asthma. In addition, the effect of the retinoid receptor ligands, all-trans-retinoic acid, and 9-cis retinoic acid, on the synthesis of 38 factors potentially involved in epithelial repair and in airway remodeling was determined in human cultured airway epithelial cells and correlated with cell migration and proliferation. Circulating retinol was similar in the three patient groups. In contrast, the epithelial expression of RARgamma, RXRalpha, and RXRgamma was greater in subjects with severe asthma, as compared with patients with milder disease and to control subjects. Retinoid receptor expression correlated positively with the proportion of morphologically intact epithelium. In vitro, retinoids up-regulated the expression of the transcripts encoding transforming growth factor (TGF)-beta1, metalloproteinase-9, beta1-integrin, and hepatocyte growth factor receptor, and promoted wound repair and chemokinesis of human airway epithelial cells without altering proliferation. Cell treatment with an anti-TGF-beta1 monoclonal antibody partially reduced retinoid-induced effects. Persistent interaction between retinoids and some of their receptors, which are overexpressed by the bronchial epithelium of individuals with severe asthma, may contribute to an abnormal repair and to airway remodeling, partly through TGF-beta1 production.

Thrombotic microangiopathy with acquired deficiency in ADAMTS 13 activity in lung transplant recipients.

BACKGROUND: Thrombotic microangiopathy may develop after solid organ transplantation, but it is usually not associated with severe deficiency in von Willebrand factor-cleaving metalloprotease (ADAMTS 13) activity. METHODS: We present the cases of two lung transplant recipients who experienced a thrombotic microangiopathy associated with an acquired severe (<5%) deficiency in ADAMTS 13 activity. RESULTS: A major feature of both cases was the occurrence of a diffuse alveolar hemorrhage. CONCLUSION: Our two cases of lung transplant patients, with thrombotic microangiopathy related to an acquired ADAMTS 13 deficiency recipients, confirm that this mechanism may also be involved in the pathogenesis of thrombotic microangiopathy developing after solid organ transplantation. Therefore, we consider that ADAMTS 13 activity should be assessed on a systematic basis in this setting.

[Airway remodeling in asthma: mechanisms and therapeutic perspectives]. / Le remodelage bronchique dans l'asthme: mécanismes et enjeux thérapeutiques.

Although asthma is classically defined as reversible airflow obstruction and often remits in younger subjects with milder disease, a proportion of asthmatics experience chronic symptoms, episodic exacerbations and persistent airway obstruction, despite the continuous use of beta 2-agonists, associated with high doses of inhaled/oral corticosteroids. These patients contribute to the majority of asthma costs through hospitalization, emergency visits, absence from work or school and use of medication. Although the mechanisms behind irreversible airflow obstruction in asthma are unclear, a prominent role has been attributed to persistent structural changes of the bronchial wall, defined as airway remodeling. Studies conducted on endobronchial biopsy samples have led to the histopathological characterization of these tissue alterations, which include chronic mucosal inflammation, extensive epithelial damage, collagen deposition, subepithelial fibrosis, increased mucous glands and airway smooth muscle hypertrophy and/or hyperplasia. Several factors, such as polypeptide growth factors and their receptors, matrix metalloproteases, intracellular molecules controlling cell death and survival, adhesion molecules and their ligands, as well a large variety of cytotoxic pro-inflammatory mediators are likely to contribute to the onset and maintenance of these tissue abnormalities. However, to date, the cellular and molecular events driving specifically these phenomena and allowing asthmatics with persistent airflow limitation to be distinguished from patients who normalize their bronchial obstruction upon adequate therapeutic management have not been identified yet. Accordingly, airway remodeling represents a major research challenge, particularly in view of the development of new therapeutic strategies specifically addressed at alleviating persistent bronchial obstruction in these otherwise intractable patients.

Airway structural alterations selectively associated with severe asthma.

To identify airway pathologic abnormalities selectively associated with severe asthma, we examined 10 control subjects, 10 patients with intermittent asthma, 15 patients with mild-to-moderate persistent asthma, 15 patients with severe persistent asthma, and 10 patients with chronic obstructive pulmonary disease. Bronchial biopsies were assessed for epithelial integrity; subepithelial basement membrane (SBM) thickness; collagen type III deposition; eosinophil, neutrophil, and fibroblast numbers; mucous gland and airway smooth muscle (ASM) areas; SBM-ASM distance; ASM hypertrophy (increased cell size); and the expression of the contractile proteins alpha-actin, smooth muscle myosin heavy-chain isoforms, myosin light-chain kinase, and the phosphorylated form of the regulatory light chain of myosin. Neither mucosal eosinophilia nor neutrophilia, epithelial damage, or SBM thickness reflected asthma severity. In contrast, higher numbers of fibroblasts (p < 0.001), an increase in collagen type III deposition (p < 0.020), larger mucous gland (p < 0.040) and ASM (p < 0.001) areas, augmented ASM cell size (p < 0.001), and myosin light-chain kinase expression (p < 0.005) distinguished patients with severe persistent asthma from patients with milder disease or with chronic obstructive pulmonary disease. Stepwise multivariate regression analysis established that fibroblast numbers and ASM cell size were negatively associated with prebronchodilator and postbronchodilator FEV1 values in patients with asthma. We conclude that fibroblast accumulation and ASM hypertrophy in proximal airways are selective determinants of severe persistent asthma.