RESUMEN
BACKGROUND: Epidural analgesia (EA) is well-accepted for pain relief during labor. Still, the impact on neonatal short-term outcome is under continuous debate. This study assessed the outcome of neonates in deliveries with and without EA in a nationwide cohort. METHODS: We analyzed the National Birth Registry of Austria between 2008 and 2017 of primiparous women with vaginal birth of singleton pregnancies. Neonatal short-term morbidity was assessed by arterial cord pH and base excess (BE). Secondary outcomes were admission to a neonatological intensive care unit, APGAR scores, and perinatal mortality. Propensity score-adjusted regression models were used to investigate the association of EA with short-term neonatal outcome. RESULTS: Of 247,536 included deliveries, 52 153 received EA (21%). Differences in pH (7.24 vs. 7.25; 97.5% CI -0.0066 to -0.0047) and BE (-5.89±3.2 vs. -6.15±3.2 mmol/L; 97.5% CI 0.32 to 0.40) with EA could be shown. APGAR score at five minutes <7 was more frequent with EA (OR 1.45; 95% CI: 1.29 to 1.63). Admission to a neonatological intensive care unit occurred more often with EA (4.7% vs. 3.4%) with an OR for EA of 1.2 (95% CI: 1.14 to 1.26). EA was not associated with perinatal mortality (OR 1.33; 95% CI: 0.79 to 2.25). CONCLUSIONS: EA showed no clinically relevant association with neonatal short-term outcome. Higher rates of NICU admission and APGAR score after five minutes <7 were observed with EA. The overall use of EA in Austria is low, and an investigation of causes may be indicated.
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Analgesia Epidural , Analgesia Obstétrica , Sistema de Registros , Humanos , Femenino , Austria/epidemiología , Estudios Retrospectivos , Recién Nacido , Embarazo , Analgesia Obstétrica/estadística & datos numéricos , Adulto , Puntaje de Apgar , Resultado del Embarazo/epidemiología , Parto Obstétrico , Mortalidad PerinatalRESUMEN
The lung can experience different oxygen concentrations, low as in hypoxia, high as under supplemental oxygen therapy, or oscillating during intermittent hypoxia as in obstructive sleep apnea or intermittent hypoxia/hyperoxia due to cyclic atelectasis in the ventilated patient. This study aimed to characterize the oxygen-condition-specific protein composition of extracellular vesicles (EVs) released from human pulmonary microvascular endothelial cells in vitro to decipher their potential role in biotrauma using quantitative proteomics with bioinformatic evaluation, transmission electron microscopy, flow cytometry, and non-activated thromboelastometry (NATEM). The release of vesicles enriched in markers CD9/CD63/CD81 was enhanced under intermittent hypoxia, strong hyperoxia and intermittent hypoxia/hyperoxia. Particles with exposed phosphatidylserine were increased under intermittent hypoxia. A small portion of vesicles were tissue factor-positive, which was enhanced under intermittent hypoxia and intermittent hypoxia/hyperoxia. EVs from treatment with intermittent hypoxia induced a significant reduction of Clotting Time in NATEM analysis compared to EVs isolated after normoxic exposure, while after intermittent hypoxia/hyperoxia, tissue factor in EVs seems to be inactive. Gene set enrichment analysis of differentially expressed genes revealed that EVs from individual oxygen conditions potentially induce different biological processes such as an inflammatory response under strong hyperoxia and intermittent hypoxia/hyperoxia and enhancement of tumor invasiveness under intermittent hypoxia.
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Vesículas Extracelulares , Hiperoxia , Humanos , Oxígeno/farmacología , Oxígeno/metabolismo , Hiperoxia/metabolismo , Proteoma/metabolismo , Células Endoteliales/patología , Tromboplastina/metabolismo , Pulmón/patología , Hipoxia/metabolismo , Vesículas Extracelulares/metabolismo , Endotelio/patologíaRESUMEN
OBJECTIVES: The aim of this study was to investigate the load and composition of cerebral microemboli in adult patients undergoing venoarterial extracorporeal life support (ECLS). METHODS: Adult ECLS patients were investigated for the presence of cerebral microemboli and compared to critically ill, pressure-controlled ventilated controls and healthy volunteers. Cerebral microemboli were detected in both middle cerebral arteries for 30 min using transcranial Doppler ultrasound. Neurological outcome (ischaemic stroke, global brain ischaemia, intracerebral haemorrhage, seizure, metabolic encephalopathy, sensorimotor sequelae and neuropsychiatric disorders) was additionally evaluated. RESULTS: Twenty ECLS patients (cannulations: 15 femoro-femoral, 4 femoro-subclavian, 1 femoro-aortic), 20 critically ill controls and 20 healthy volunteers were analysed. ECLS patients had statistically significantly more cerebral microemboli than critically ill controls {123 (43-547) [median (interquartile range)] vs 35 (16-74), difference: 88 [95% confidence interval (CI) 19-320], P = 0.023} and healthy volunteers [11 (5-12), difference: 112 (95% CI 45-351), P < 0.0001]. In ECLS patients, 96.5% (7346/7613) of cerebral microemboli were of gaseous composition, while solid cerebral microemboli [1 (0-5)] were detected in 12 out of 20 patients. ECLS patients had more neurological complications than critically ill controls (12/20 vs 3/20, P = 0.003). In ECLS patients, a high microembolic rate (>100/30 min) tended to be associated with neurological complications including ischaemic stroke, neuropsychiatric disorders, sensorimotor sequelae and non-convulsive status epilepticus (odds ratio 4.5, 95% CI 0.46-66.62; P = 0.559). CONCLUSIONS: Our results indicate that adult ECLS patients are continuously exposed to many gaseous and, frequently, to few solid cerebral microemboli. Prolonged cerebral microemboli formation may contribute to neurological morbidity related to ECLS treatment. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT02020759, https://clinicaltrials.gov/ct2/show/NCT02020759?term=erdoes&rank=1.
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Isquemia Encefálica , Oxigenación por Membrana Extracorpórea , Embolia Intracraneal , Accidente Cerebrovascular , Adulto , Isquemia Encefálica/etiología , Estudios de Cohortes , Oxigenación por Membrana Extracorpórea/efectos adversos , Humanos , Embolia Intracraneal/diagnóstico por imagen , Embolia Intracraneal/etiología , Estudios Prospectivos , Ultrasonografía Doppler Transcraneal/efectos adversosRESUMEN
BACKGROUND: Epidural-related maternal fever (ERMF) is an adverse effect of epidural analgesia during labor and is associated with perinatal and neonatal morbidity. Local anesthetics have been proposed to trigger ERMF via sterile inflammation. Ropivacaine is currently the most frequently used epidural anesthetic and considered least toxic. This study investigates molecular effects of ropivacaine on human umbilical vein endothelial cells (HUVECs) as model system for endothelial cells and human placental trophoblasts (TBs), compares the effects to the putative anti-inflammatory lidocaine and investigates the partially alleviating impact of the anti-inflammatory corticosteroid dexamethasone. METHODS: HUVECs and TBs were exposed to ropivacaine (35 µM-7 mM) or lidocaine (21 mM) with or without dexamethasone (1 µM). AnnexinV/propidium iodide staining and lactate dehydrogenase release were used to analyze apoptosis and cytotoxicity. Proinflammatory interleukins-6 (IL-6) and IL-8 as well as prostaglandin E2 (PGE2) were measured by enzyme-linked immunosorbent assay (ELISA), while activation of signaling pathways was detected by Western blotting. Oxidative stress was visualized by live cell imaging and quantification of antioxidant proteins, intercellular adhesion molecule 1, vascular cell adhesion molecule 1, platelet endothelial cell adhesion molecule 1, cyclooxygenase 2, and mitochondrial deoxyribonucleic acid by real-time polymerase chain reaction. Dissipation of the mitochondrial membrane potential was assessed with cytofluorimetric analysis using the J-Aggregate (JC-1 staining [cytofluorimetric analysis using the J-Aggregate]). RESULTS: Ropivacaine exposure dose-dependently induced apoptosis and an increased release of IL-6, IL-8, and PGE2 from HUVECs and TBs. Furthermore, caspase-3, nuclear factor-κB, and p38 mitogen-activated protein kinase pathways were activated, while extracellular signal-regulated kinase 1/2 and protein kinase B (Akt) were dephosphorylated. Downregulation of antioxidative proteins induced oxidative stress and upregulation of ICAM1, VCAM1, and PECAM1 possibly facilitate leukocyte transmigration. Mitochondrial effects included increased release of the proinflammatory mitochondrial DNA damage-associated molecular patterns, but no significant dissipation of the mitochondrial membrane potential. Conversely, lidocaine exhibited repression of IL-6 and IL-8 release over all time points, and early downregulation of COX2 and cell adhesion molecules, which was followed by a late overshooting reaction. Dexamethasone reduced especially inflammatory effects, but as an inducer of mitophagy, had negative long-term effects on mitochondrial function. CONCLUSIONS: This study suggests that ropivacaine causes cellular injury and death in HUVECs and TBs via different signaling pathways. The detrimental effects induced by ropivacaine are only partially blunted by dexamethasone. This observation strengthens the importance of inflammation in ERMF.
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Anestesia Epidural/efectos adversos , Anestésicos Locales/efectos adversos , Apoptosis/efectos de los fármacos , Fiebre/metabolismo , Mediadores de Inflamación/metabolismo , Ropivacaína/efectos adversos , Anestésicos Locales/administración & dosificación , Apoptosis/fisiología , Células Cultivadas , Relación Dosis-Respuesta a Droga , Femenino , Fiebre/inducido químicamente , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Embarazo , Ropivacaína/administración & dosificación , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiologíaRESUMEN
BACKGROUND: Tenascin C (TN-C) is considered to play a pathophysiological role in maladaptive left ventricular remodeling. Yet, the mechanism underlying TN-C-dependent cardiac dysfunction remains elusive. METHOD: The present study was designed to investigate the effect of hypoxia and hypertrophic stimuli on TN-C expression in H9c2 cells and its putative regulation by epigenetic mechanisms, namely DNA promoter methylation and microRNAs. In addition, rats subjected to myocardial infarction (MI) were investigated. H9c2 cells were subjected to oxygen and glucose deprivation; incubated with angiotensin II (Ang II); or human TN-C (hTN-C) purified protein. Hypertrophic and fibrotic markers, TN-C promoter methylation as well as mir-335 expression were assessed by reverse transcription and quantitative polymerase chain reaction while TN-C protein levels were assessed by ELISA. RESULTS: Tn-C mRNA expression was markedly increased by both oxygen and glucose deprivation and Ang II (Pâ<â0.01, respectively). In addition, Ang-II-dependent TN-C upregulation was explained by reduced promoter methylation (Pâ<â0.05). Cells treated with hTN-C displayed upregulation of Bnp, Mmp2, ß-Mhc, integrin α6 and integrin ß1. Furthermore, hTN-C treated cells showed a significant reduction in adenosine monophosphate and adenosine triphosphate levels. In vivo, plasma and myocardial TN-C levels were increased 7 days post MI (Pâ<â0.05, respectively). This increment in TN-C was accompanied by upregulation of mir-335 (Pâ<â0.01). In conclusion, both hypoxic and hypertrophic stimuli lead to epigenetically driven TN-C upregulation and subsequent impairment of cellular energy metabolism in cardiomyoblasts. CONCLUSION: These findings might enlighten our understanding on maladaptive left ventricular remodeling and direct towards a strong involvement of TN-C.
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Cardiomegalia/metabolismo , Metilación de ADN , Hipoxia/metabolismo , Infarto del Miocardio/metabolismo , Tenascina/metabolismo , Angiotensina II , Animales , Enfermedad de la Arteria Coronaria , Metabolismo Energético , Epigénesis Genética , Matriz Extracelular/metabolismo , Proteínas de la Matriz Extracelular , Fibrosis , Cardiopatías/metabolismo , Humanos , Hipertrofia , Masculino , Metaloproteinasa 2 de la Matriz/metabolismo , MicroARNs/metabolismo , Miocardio/metabolismo , Proteínas del Tejido Nervioso , Ratas , Tenascina/genética , Remodelación VentricularRESUMEN
BACKGROUND: Mechanical ventilation can lead to ventilator-induced lung injury (VILI). In addition to the well-known mechanical forces of volutrauma, barotrauma, and atelectrauma, non-mechanical mechanisms have recently been discussed as contributing to the pathogenesis of VILI. One such mechanism is oscillations in partial pressure of oxygen (PO2) which originate in lung tissue in the presence of within-breath recruitment and derecruitment of alveoli. The purpose of this study was to investigate this mechanism's possible independent effects on lung tissue and inflammation in a porcine model. METHODS: To separately study the impact of PO2 oscillations on the lungs, an in vivo model was set up that allowed for generating mixed-venous PO2 oscillations by the use of veno-venous extracorporeal membrane oxygenation (vvECMO) in a state of minimal mechanical stress. While applying the identical minimal-invasive ventilator settings, 16 healthy female piglets (weight 50 ± 4 kg) were either exposed for 6 h to a constant mixed-venous hemoglobin saturation (SmvO2) of 65% (which equals a PmvO2 of 41 Torr) (control group), or an oscillating SmvO2 (intervention group) of 40-90% (which equals PmvO2 oscillations of 30-68 Torr)-while systemic normoxia in both groups was maintained. The primary endpoint of histologic lung damage was assessed by ex vivo histologic lung injury scoring (LIS), the secondary endpoint of pulmonary inflammation by qRT-PCR of lung tissue. Cytokine concentration of plasma was carried out by ELISA. A bioinformatic microarray analysis of lung samples was performed to generate hypotheses about underlying pathomechanisms. RESULTS: The LIS showed significantly more severe damage of lung tissue after exposure to PO2 oscillations compared to controls (0.53 [0.51; 0.58] vs. 0.27 [0.23; 0.28]; P = 0.0025). Likewise, a higher expression of TNF-α (P = 0.0127), IL-1ß (P = 0.0013), IL-6 (P = 0.0007), and iNOS (P = 0.0013) in lung tissue was determined after exposure to PO2 oscillations. Cytokines in plasma showed a similar trend between the groups, however, without significant differences. Results of the microarray analysis suggest that inflammatory (IL-6) and oxidative stress (NO/ROS) signaling pathways are involved in the pathology linked to PO2 oscillations. CONCLUSIONS: Artificial mixed-venous PO2 oscillations induced lung damage and pulmonary inflammation in healthy animals during lung protective ventilation. These findings suggest that PO2 oscillations represent an independent mechanism of VILI.
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Neumonía/etiología , Lesión Pulmonar Inducida por Ventilación Mecánica/fisiopatología , Animales , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Alemania , Oxígeno/administración & dosificación , Oxígeno/efectos adversos , Oxígeno/uso terapéutico , Presión Parcial , Neumonía/patología , Neumonía/fisiopatología , Respiración Artificial/efectos adversos , Respiración Artificial/métodos , Respiración Artificial/normas , Mecánica Respiratoria/fisiología , Porcinos , Lesión Pulmonar Inducida por Ventilación Mecánica/etiología , Lesión Pulmonar Inducida por Ventilación Mecánica/patologíaRESUMEN
BACKGROUND: Critically ill patients with acute respiratory failure admitted to an intensive care unit are at high risk for cerebral hypoxia. We investigated the impact of continuous positive airway pressure (CPAP) therapy on regional cerebral tissue oxygenation (rSO2). MATERIALS AND METHODS: In total, 40 extubated surgical intensive care unit patients requiring classic oxygen therapy (COT) for acute respiratory failure were examined. Near-infrared spectroscopy (INVOS 5100C, Covidien) was used for 30 minutes to detect bilateral rSO2 during COT via facemask (6 L/min) and CPAP therapy (40% fraction of inspired oxygen, 8 cm H2O CPAP) using a randomized crossover study design. Patients served as their own control. Continuous hemodynamic routine monitoring and blood gas analysis were performed. The effect of CPAP therapy on rSO2 and influence of assessed covariables were investigated using a mixed linear model. RESULTS: Median rSO2 increased from 57.9% (95% confidence interval [CI], 54.2-61.5) during COT to 62.8% (95% CI, 59.2-66.5) during CPAP therapy (P<0.0001). The estimated difference from the mixed model between COT and CPAP is -5.0 (95% CI, -6.3 to -3.7). Median arterial partial pressure of carbon dioxide decreased from 47.8±5.1 mm Hg during COT to 43.1±5 mm Hg during CPAP (P<0.001), whereas arterial partial pressure of oxygen remained unchanged (P=0.329). In total, 23% of patients had SO2 levels <50%, with a higher prevalence under COT. CONCLUSIONS: Our results reveal that CPAP therapy compared with COT may influence rSO2 in patients with acute respiratory failure. However, the cause of the rSO2 increase following CPAP application remains to be elucidated, and the accuracy of cerebral oximetry during CPAP therapy in patients with acute respiratory failure remains questionable.
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Presión de las Vías Aéreas Positiva Contínua/métodos , Insuficiencia Respiratoria/diagnóstico , Espectroscopía Infrarroja Corta/métodos , Adulto , Anciano , Anciano de 80 o más Años , Análisis de los Gases de la Sangre , Cuidados Críticos , Enfermedad Crítica , Estudios Cruzados , Femenino , Frente , Humanos , Hipoxia Encefálica/prevención & control , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico , Oxígeno/uso terapéuticoRESUMEN
BACKGROUND: The noble gas argon induces cardioprotection in a rabbit model of myocardial ischemia and reperfusion. However, no studies in human primary cells or subjects have been performed so far. We used human cardiac myocyte-like progenitor cells (HCMs) to investigate the protective effect on the cellular level. METHODS: HCMs were pretreated with 30% or 50% argon before oxygen-glucose deprivation (OGD) and reperfusion. We evaluated apoptotic states by flow cytometry and the activation of mitogen-activated protein kinase (MAPKs) members extracellular signal-regulated kinase (ERK), c-jun N-terminal kinase (JNK), p38 MAPkinase, and protein kinase B (Akt) by Westernblot analysis and by activity assays of downstream transcription factors. Specific inhibitors were used to proof a significant participation of these pathways in the protection by argon. Beneficial effects were further assessed by TdT-mediated dUTP-biotin nick end labeling (TUNEL) assay, lactate dehydrogenase (LDH), mitochondrial deoxyribonucleic acid (mtDNA), and cytokine release. RESULTS: Pretreatment with 30% or 50% argon for 90âmin before OGD resulted in a significant protection of HCMs against apoptosis. This effect was reversed by the application of MAPK and Akt inhibitors during argon exposure. Argon 30% reduced the release of LDH by 33% and mtDNA by 45%. The release of interleukin 1ß was reduced by 44% after OGD and more than 90% during reperfusion. CONCLUSIONS: Pretreatment with argon protects HCMs from apoptosis under ischemic conditions via activation of Akt, Erk, and biphasic regulation of JNK. Argon gas is cheap and easily administrable, and might be a novel therapy to reduce myocardial ischemia-reperfusion injury.
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Argón/farmacología , Miocitos Cardíacos/citología , Miocitos Cardíacos/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Células Madre/citología , Células Madre/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Citometría de Flujo , Humanos , Etiquetado Corte-Fin in Situ , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , L-Lactato Deshidrogenasa/metabolismo , Conejos , Transducción de Señal/efectos de los fármacosRESUMEN
AIMS: Left ventricular (LV) hypertrophy is characterized by cardiomyocyte hypertrophy and interstitial fibrosis ultimately leading to increased myocardial stiffness and reduced contractility. There is substantial evidence that the altered expression of matrix metalloproteinases (MMP) and Tenascin-C (TN-C) are associated with the progression of adverse LV remodeling. However, the role of TN-C in the development of LV hypertrophy because of chronic pressure overload as well as the regulatory role of TN-C on MMPs remains unknown. METHODS AND RESULTS: In a knockout mouse model of TN-C, we investigated the effect of 10 weeks of pressure overload using transverse aortic constriction (TAC). Cardiac function was determined by magnetic resonance imaging. The expression of MMP-2 and MMP-9, CD147 as well as myocardial fibrosis were assessed by immunohistochemistry. The expression of TN-C was assessed by RT-qPCR and ELISA. TN-C knockout mice showed marked reduction in fibrosis (Pâ<â0.001) and individual cardiomyocytes size (Pâ<â0.01), in expression of MMP-2 (Pâ<â0.05) and MMP-9 (Pâ<â0.001) as well as preserved cardiac function (Pâ<â0.01) in comparison with wild-type mice after 10 weeks of TAC. In addition, CD147 expression was markedly increased under pressure overload (Pâ<â0.01), irrespectively of genotype. TN-C significantly increased the expression of the markers of hypertrophy such as ANP and BNP as well as MMP-2 in H9c2 cells (Pâ<â0.05, respectively). CONCLUSION: Our results are pointed toward a novel signaling mechanism that contributes to LV remodeling via MMPs upregulation, cardiomyocyte hypertrophy as well as myocardial fibrosis by TN-C under chronic pressure overload.
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Hipertensión/complicaciones , Hipertrofia Ventricular Izquierda/genética , Hipertrofia Ventricular Izquierda/metabolismo , Miocardio/patología , Tenascina/genética , Tenascina/metabolismo , Remodelación Ventricular/genética , Animales , Basigina/genética , Basigina/metabolismo , Gasto Cardíaco , Línea Celular , Fibrosis , Genotipo , Hipertrofia Ventricular Izquierda/fisiopatología , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Miocitos Cardíacos/patología , Péptido Natriurético Encefálico/metabolismo , Transducción de Señal , Remodelación Ventricular/fisiologíaRESUMEN
Stem cell therapy for acute myocardial infarction (AMI) seemed to be a promising therapy, however, large clinical trials brought differential outcome. It has been shown that paracrine effects of secretomes of stem cells rather than cell therapy might play a fundamental role. The present study seeks to compare cell processing protocols of clinical trials and investigate effects of differential cell culture conditions on chemokine secretion and functional effects. Different secretomes are compared regarding IL-8, VEGF, MCP-1, and TNF-alpha secretion. Secretome mediated effects are evaluated on endothelial cell (HUVEC) tube formation and migration. Cardioprotective signaling kinases in human cardiomyocytes are determined by Western immunoblotting. Cells processed according to the REPAIR-AMI protocol secrete significantly higher amounts of IL-8 (487.3 ± 1231.1 vs 9.1 ± 8.2 pg mL-1 ; p < 0.05). REAPIR-AMI supernatants lead to significantly pronounced tube formation and migration on HUVEC and enhance the phosphorylation of Akt, ERK, and CREB. Cell processing conditions have a major impact on the composition of the secretome. The REPAIR-AMI secretome significantly enhances proangiogenic chemokine secretion, angiogenesis, cell migration, and cardioprotective signaling pathways. These results might explain differential outcomes between clinical trials. Optimizing cell processing protocols with special regards to paracrine factors, might open a new therapeutic concept for improving patient outcome.
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Interleucina-8 , Infarto del Miocardio/terapia , Trasplante de Células Madre , Células Madre , Células de la Médula Ósea/citología , Células de la Médula Ósea/metabolismo , Células de la Médula Ósea/fisiología , Movimiento Celular/fisiología , Ensayos Clínicos como Asunto , Medios de Cultivo Condicionados , Citocinas/análisis , Citocinas/metabolismo , Células Endoteliales de la Vena Umbilical Humana , Humanos , Interleucina-8/análisis , Interleucina-8/metabolismo , Transducción de Señal , Células Madre/citología , Células Madre/metabolismo , Células Madre/fisiologíaRESUMEN
BACKGROUND: Perioperative oxygen (O2) therapy can cause hyperoxia. Extreme hyperoxia can injure the cardiovascular system and remote organs. OBJECTIVE: Our primary objective was to test the hypothesis that exposure to moderate hyperoxia will induce injury to human umbilical vein endothelial cells (HUVECs), a model for studying the vascular endothelium under controlled conditions. DESIGN: In-vitro cell culture study. SETTING: Department of Anaesthesia, General Intensive Care and Pain Management, Medical University of Vienna, Austria. Study period from the beginning of October 2013 to the end of July 2014. CELLS: HUVECs were isolated from fresh umbilical cords. INTERVENTIONS: HUVECs were exposed to constant hyperoxia (40% O2), cyclic hyperoxia/anoxia (40%/0% O2, average 20% O2), constant normoxia (21% O2) and constant anoxia (0% O2) using a cell culture bioreactor. MAIN OUTCOME MEASURES: Cell growth, viability and release of IL-6, IL-8 and macrophage migration inhibitory factor were assessed at baseline and after 6, 12, 24 and 48âh of treatment. A phosphokinase array was performed after 60âmin of treatment to identify activated cellular signalling pathways. RESULTS: Constant hyperoxia and cyclic hyperoxia/anoxia impeded cell growth, reduced viability, triggered a proinflammatory response, proven by IL-6, IL-8 and migration inhibitory factor release, and induced apoptosis and necrosis. The inflammatory and cytotoxicity responses were highest in the constant hyperoxia group. Phosphokinase arrays revealed that different O2 concentrations activated distinct sets of cytoprotective and cell death-associated kinases, including mitogen-activated protein kinases, Src kinases, p53, Akt, mitogen-activated and stress-activated kinase, Lyn, Lck, p70S6, signal transducers and activators of transcription 5b and 6, glycogen synthase kinase 3a/b and 5' AMP-activated protein kinases 1/2. CONCLUSION: Continuous moderate hyperoxia and cyclic moderate hyperoxia/anoxia-induced endothelial inflammation, apoptosis and necrosis. Given the large surface area of the vascular endothelium, moderately elevated O2 levels may contribute to cardiovascular inflammation and injury. TRIAL REGISTRATION: This in-vitro study was not registered in a database.
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Apoptosis/fisiología , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Hiperoxia/metabolismo , Mediadores de Inflamación/metabolismo , Proliferación Celular/fisiología , Supervivencia Celular/fisiología , Células Cultivadas , Células Endoteliales de la Vena Umbilical Humana/patología , Humanos , Hiperoxia/patología , Inflamación/metabolismo , Inflamación/patología , Necrosis/metabolismo , Necrosis/patologíaRESUMEN
BACKGROUND: Continuous venovenous hemodialysis (CVVHD) may generate microemboli that cross the pulmonary circulation and reach the brain. The aim of the present study was to quantify (load per time interval) and qualify (gaseous vs. solid) cerebral microemboli (CME), detected as high-intensity transient signals, using transcranial Doppler ultrasound. MATERIALS AND METHODS: Twenty intensive care unit (ICU group) patients requiring CVVHD were examined. CME were recorded in both middle cerebral arteries for 30 minutes during CVVHD and a CVVHD-free interval. Twenty additional patients, hospitalized for orthopedic surgery, served as a non-ICU control group. Statistical analyses were performed using the Mann-Whitney U test or the Wilcoxon matched-pairs signed-rank test, followed by Bonferroni corrections for multiple comparisons. RESULTS: In the non-ICU group, 48 (14.5-169.5) (median [range]) gaseous CME were detected. In the ICU group, the 67.5 (14.5-588.5) gaseous CME detected during the CVVHD-free interval increased 5-fold to 344.5 (59-1019) during CVVHD (P<0.001). The number of solid CME was low in all groups (non-ICU group: 2 [0-5.5]; ICU group CVVHD-free interval: 1.5 [0-14.25]; ICU group during CVVHD: 7 [3-27.75]). CONCLUSIONS: This observational pilot study shows that CVVHD was associated with a higher gaseous but not solid CME burden in critically ill patients. Although the differentiation between gaseous and solid CME remains challenging, our finding may support the hypothesis of microbubble generation in the CVVHD circuit and its transpulmonary translocation toward the intracranial circulation. Importantly, the impact of gaseous and solid CME generated during CVVHD on brain integrity of critically ill patients currently remains unknown and is highly debated.
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Enfermedad Crítica , Embolia Aérea/diagnóstico por imagen , Hemofiltración , Embolia Intracraneal/diagnóstico por imagen , Adulto , Anciano , Cuidados Críticos , Diagnóstico Diferencial , Embolia Aérea/epidemiología , Embolia Aérea/terapia , Femenino , Humanos , Infarto de la Arteria Cerebral Media/diagnóstico por imagen , Unidades de Cuidados Intensivos , Embolia Intracraneal/epidemiología , Embolia Intracraneal/terapia , Masculino , Microburbujas , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , Ultrasonografía Doppler TranscranealAsunto(s)
Anestesia , Anestésicos por Inhalación/administración & dosificación , Ondas Encefálicas/efectos de los fármacos , Circulación Cerebrovascular/efectos de los fármacos , Monitores de Conciencia , Electroencefalografía/instrumentación , Monitorización Neurofisiológica Intraoperatoria/instrumentación , Éteres Metílicos/administración & dosificación , Microcirculación/efectos de los fármacos , Algoritmos , Craneotomía , Estudios Cruzados , Alemania , Humanos , Monitorización Neurofisiológica Intraoperatoria/métodos , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Sevoflurano , Procesamiento de Señales Asistido por Computador , Factores de TiempoRESUMEN
OBJECTIVE: Systemic PaO2 oscillations occur during cyclic recruitment and derecruitment of atelectasis in acute respiratory failure and might harm brain tissue integrity. DESIGN: Controlled animal study. SETTING: University research laboratory. SUBJECTS: Adult anesthetized pigs. INTERVENTIONS: Pigs were randomized to a control group (anesthesia and extracorporeal circulation for 20 hr with constant PaO2, n = 10) or an oscillation group (anesthesia and extracorporeal circulation for 20 hr with artificial PaO2 oscillations [3 cycles min⻹], n = 10). Five additional animals served as native group (n = 5). MEASUREMENTS AND MAIN RESULTS: Outcome following exposure to artificial PaO2 oscillations compared with constant PaO2 levels was measured using 1) immunohistochemistry, 2) real-time polymerase chain reaction for inflammatory markers, 3) receptor autoradiography, and 4) transcriptome analysis in the hippocampus. Our study shows that PaO2 oscillations are transmitted to brain tissue as detected by novel ultrarapid oxygen sensing technology. PaO2 oscillations cause significant decrease in NISSL-stained neurons (p < 0.05) and induce inflammation (p < 0.05) in the hippocampus and a shift of the balance of hippocampal neurotransmitter receptor densities toward inhibition (p < 0.05). A pathway analysis suggests that cerebral immune and acute-phase response may play a role in mediating PaO2 oscillation-induced brain injury. CONCLUSIONS: Artificial PaO2 oscillations cause mild brain injury mediated by inflammatory pathways. Although artificial PaO2 oscillations and endogenous PaO2 oscillations in lung-diseased patients have different origins, it is likely that they share the same noxious effect on the brain. Therefore, PaO2 oscillations might represent a newly detected pathway potentially contributing to the crosstalk between acute lung and remote brain injury.
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Lesiones Encefálicas/etiología , Lesiones Encefálicas/fisiopatología , Respiración Artificial/efectos adversos , Respiración Artificial/métodos , Síndrome de Dificultad Respiratoria/terapia , Animales , Análisis de los Gases de la Sangre , Oxigenación por Membrana Extracorpórea/métodos , Mediadores de Inflamación/metabolismo , Atelectasia Pulmonar/prevención & control , ARN Complementario/metabolismo , Distribución Aleatoria , Reacción en Cadena en Tiempo Real de la Polimerasa , Porcinos , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiónico/metabolismo , Ácido gamma-Aminobutírico/metabolismoRESUMEN
BACKGROUND: Vibration response imaging (VRI) is a bedside technology to monitor ventilation by detecting lung sound vibrations. It is currently unknown whether VRI is able to accurately monitor the local distribution of ventilation within the lungs. We therefore compared VRI to electrical impedance tomography (EIT), an established technique used for the assessment of regional ventilation. METHODOLOGY/PRINCIPAL FINDINGS: Simultaneous EIT and VRI measurements were performed in the healthy and injured lungs (ALI; induced by saline lavage) at different PEEP levels (0, 5, 10, 15 mbar) in nine piglets. Vibration energy amplitude (VEA) by VRI, and amplitudes of relative impedance changes (rel.ΔZ) by EIT, were evaluated in seven regions of interest (ROIs). To assess the distribution of tidal volume (VT) by VRI and EIT, absolute values were normalized to the VT obtained by simultaneous spirometry measurements. Redistribution of ventilation by ALI and PEEP was detected by VRI and EIT. The linear correlation between pooled VT by VEA and rel.ΔZ was R(2)â=â0.96. Bland-Altman analysis showed a bias of -1.07±24.71 ml and limits of agreement of -49.05 to +47.36 ml. Within the different ROIs, correlations of VT-distribution by EIT and VRI ranged between R(2) values of 0.29 and 0.96. ALI and PEEP did not alter the agreement of VT between VRI and EIT. CONCLUSIONS/SIGNIFICANCE: Measurements of regional ventilation distribution by VRI are comparable to those obtained by EIT.
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Diagnóstico por Imagen/métodos , Ventilación Pulmonar/fisiología , Tomografía/métodos , Vibración , Análisis de Varianza , Animales , Impedancia Eléctrica , Modelos Estadísticos , Espirometría , PorcinosRESUMEN
BACKGROUND: The lectin-like domain of TNF-α mimicked by an inhaled TIP peptide represents a novel approach to attenuate a pulmonary edema in respiratory failure, which is on the threshold to clinical application. In extension to a previously published study, which reported an improved pulmonary function following TIP peptide inhalation in a porcine model of lavage-induced lung injury, a post-hoc comparison to additional experiments was conducted. This analysis addresses the hypothesis that oleic acid injection-induced capillary leakage and alveolar necrosis blunts the previously reported beneficial effects of TIP peptide inhalation in a porcine model. FINDINGS: Following animal care committee approval lung injury was induced by oleic acid injection in six pigs with a setting strictly according to a previously published protocol that was used for lung-lavaged pigs. Ventilation/perfusion-distribution by multiple inert gas elimination, parameters of gas exchange and pulmonary edema were assessed as surrogates of the pulmonary function. A significantly improved ventilation/perfusion-distribution following TIP inhalation was recognized only in the bronchoalveolar lavage model but not following oleic acid injection. The time course after oleic acid injection yielded no comparable impact of the TIP peptide on gas exchange and edema formation. CONCLUSIONS: Reported beneficial effects of the TIP peptide on gas exchange and pulmonary edema were not reproducible in the oleic acid injection model. This analysis assumes that sustained alveolar epithelial necrosis as induced by oleic acid injection may inhibit the TIP-induced edema resolution. Regarding the on-going clinical development of the TIP peptide this approach should hardly be effective in states of severe alveolar epithelial damage.
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Lesión Pulmonar/tratamiento farmacológico , Péptidos/administración & dosificación , Péptidos/uso terapéutico , Administración por Inhalación , Animales , Agua Pulmonar Extravascular/metabolismo , Rendimiento Pulmonar/fisiología , Lesión Pulmonar/patología , Lesión Pulmonar/fisiopatología , Ácido Oléico , Oxígeno/metabolismo , Perfusión , Ventilación Pulmonar/fisiología , Sus scrofa , Factores de TiempoRESUMEN
BACKGROUND: Measurement of partial pressure of oxygen (PO2) at high temporal resolution remains a technological challenge. This study introduces a novel PO2 sensing technology based on Multi-Frequency Phase Fluorimetry (MFPF). The aim was to validate MFPF against polarographic Clark-type electrode (CTE) PO2 measurements. METHODOLOGY/PRINCIPAL FINDINGS: MFPF technology was first investigated in Nâ=â8 anaesthetised pigs at FIO2 of 0.21, 0.4, 0.6, 0.8 and 1.0. At each FIO2 level, blood samples were withdrawn and PO2 was measured in vitro with MFPF using two FOXY-AL300 probes immediately followed by CTE measurement. Secondly, MFPF-PO2 readings were compared to CTE in an artificial circulatory setup (human packed red blood cells, haematocrit of 30%). The impacts of temperature (20, 30, 40°C) and blood flow (0.8, 1.6, 2.4, 3.2, 4.0 L min(-1)) on MFPF-PO2 measurements were assessed. MFPF response time in the gas- and blood-phase was determined. Porcine MFPF-PO2 ranged from 63 to 749 mmHg; the corresponding CTE samples from 43 to 712 mmHg. Linear regression: CTEâ=â15.59+1.18*MFPF (R(2)â=â0.93; P<0.0001). Bland Altman analysis: meandiff 69.2 mmHg, rangediff -50.1/215.6 mmHg, 1.96-SD limits -56.3/194.8 mmHg. In artificial circulatory setup, MFPF-PO2 ranged from 20 to 567 mmHg and CTE samples from 11 to 575 mmHg. Linear regression: CTEâ=â-8.73+1.05*MFPF (R(2)â=â0.99; P<0.0001). Bland-Altman analysis: meandiff 6.6 mmHg, rangediff -9.7/20.5 mmHg, 1.96-SD limits -12.7/25.8 mmHg. Differences between MFPF and CTE-PO2 due to variations of temperature were less than 6 mmHg (range 0-140 mmHg) and less than 35 mmHg (range 140-750 mmHg); differences due to variations in blood flow were less than 15 mmHg (all P-values>0.05). MFPF response-time (monoexponential) was 1.48±0.26 s for the gas-phase and 1.51±0.20 s for the blood-phase. CONCLUSIONS/SIGNIFICANCE: MFPF-derived PO2 readings were reproducible and showed excellent correlation and good agreement with Clark-type electrode-based PO2 measurements. There was no relevant impact of temperature and blood flow upon MFPF-PO2 measurements. The response time of the MFPF FOXY-AL300 probe was adequate for real-time sensing in the blood phase.