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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Cortical spreading ischaemia and delayed ischaemic neurological deficits after subarachnoid haemorrhage

Dreier, Jens P. 21 July 2003 (has links)
Die Kopplung zwischen neuronaler Aktivität und cerebralem Blutfluss ist ein fundamentaler Prozess, der alle cerebralen Funktionen begleitet. Das Thema meiner Habilitation ist die Entdeckung einer neuen Ischämievariante, bei der neuronale Aktivierung eine cerebrale Ischämie auslöst, indem sich die Kopplung zwischen neuronaler Aktivierung und cerebralem Blutfluss umkehrt. Diese Umkehrung wird durch Produkte roter Blutkörperchen im Subarachnoidalraum hervorgerufen. Die eigentümlichste Eigenschaft dieser Ischämievariante ist ihre Wanderung im cerebralen Cortex gemeinsam mit der Welle neuronaler Aktivierung. Deshalb habe ich das Phänomen cortical spreading ischaemia genannt. Das vorgestellte tierexperimentelle Modell könnte für die verzögerten ischämischen neurologischen Defizite nach Subarachnoidalblutung Implikationen besitzen. Die Verbindung mit diesem klinischen Syndrom basiert auf: (a) der Induktion der cortical spreading ischaemia durch Produkte roter Blutkörperchen im Subarachnoidalraum, (b) der Übereinstimmung im Läsionsmuster mit corticalen ischämischen Infarkten, und (c) den therapeutischen Effekten von Nimodipin und mässiger hypervolämischer Hämodilution im klinischen Syndrom und im Tiermodell. Mit Hilfe dieses Modells ist es zum ersten Mal gelungen, experimentell die Hypothese zu bestätigen, dass Produkte roter Blutkörperchen eine cerebrale Ischämie induzieren können. Ich hoffe, dass das Modell dazu beitragen wird, neue Strategien bei der Behandlung von Patienten mit Subarachnoidalblutung zu entwickeln. / The coupling between neuronal activity and cerebral blood flow is a fundamental process, which underpins all cerebral functions. The topic of my Habilitation is the discovery of a new variant of ischaemia in which neuronal activation triggers a cerebral ischaemic event through the inversion of the coupling between neuronal activation and cerebral blood flow. This inversion occurs when red blood cell products are present in the subarachnoid space. The most distinct feature of this variant of ischaemia is its propagation in the cerebral cortex together with the wave of neuronal activation. Therefore, I named the phenomenon cortical spreading ischaemia . The presented animal model may have implications for the delayed ischaemic neurological deficits after subarachnoid haemorrhage. The link with this clinical syndrome has been based: (a) on the induction of cortical spreading ischaemia by red blood cell products in the subarachnoid space, (b) the correspondence between the characteristic patterns of the cortical ischaemic lesions, and (c) the therapeutic effects of nimodipine and moderate hypervolaemic haemodilution in clinical syndrome and animal model. With the aid of this model, it was possible to experimentally confirm the hypothesis that red blood cell products can induce cerebral ischaemia. I hope that the model will contribute to develop new strategies for the treatment of patients with subarachnoid haemorrhage.
82

Physiological responses to brain tissue hypoxia and blood flow after acute brain injury

Flynn, Liam Martin Clint January 2018 (has links)
This thesis explores physiological changes occurring after acute brain injury. The first two chapters focus on traumatic brain injury (TBI), a significant cause of disability and death worldwide. I discuss the evidence behind current management of secondary brain injury with emphasis on partial brain oxygen tension (PbtO2) and intracranial pressure (ICP). The second chapter describes a subgroup analysis of the effect of hypothermia on ICP and PbtO2 in 17 patients enrolled to the Eurotherm3235 trial. There was a mean decrease in ICP of 4.1 mmHg (n=9, p < 0.02) and a mean decrease in PbtO2 (7.8 ± 3.1 mmHg (p < 0.05)) in the hypothermia group that was not present in controls. The findings support previous studies in demonstrating a decrease in ICP with hypothermia. Decreased PbtO2 could partially explain worse outcomes seen in the hypothermia group in the Eurotherm3235 trial. Further analysis of PbtO2 and ICP guided treatment is needed. The third chapter focuses on delayed cerebral ischaemia (DCI) after aneurysmal subarachnoid haemorrhage (aSAH), another form of acute brain injury that causes significant morbidity and mortality. I include a background of alpha-calcitonin gene-related peptide (αCGRP), a potential treatment of DCI, along with results from a systematic review and meta-analysis of nine experimental models investigating αCGRP. The meta-analysis demonstrates a 40.8 ± 8.2% increase in cerebral vessel diameter in those animals treated with αCGRP compared with controls (p < 0.0005, 95% CI 23.7 to 57.9). Neurobehavioural scores were reported in four publications and showed a Physiological responses to brain tissue hypoxia and blood flow after acute brain injury standardised mean difference of 1.31 in favour of αCGRP (CI -0.49 to 3.12). I conclude that αCGRP reduces cerebral vessel narrowing seen after SAH in animal studies but note that there is insufficient evidence to determine its effect on functional outcomes. A review of previous trials of αCGRP administration in humans is included, in addition to an original retrospective analysis of CSF concentrations of αCGRP in humans. Enzyme-linked immunosorbent assay of CSF (n = 22) was unable to detect αCGRP in any sample, which contrasts with previous studies and was likely secondary to study methodology. Finally, I summarise by discussing a protocol I designed for a dose-toxicity study involving the intraventricular administration of αCGRP to patients with aSAH and provide some recommendations for future research. This protocol was based upon the systematic review and was submitted to the Medical Research Council's DPFS funding stream during the PhD.
83

Biomarcadores genéticos na hemorragia subaracnoidea aneurismática em pacientes da Amazônia / Genetic biomarkers in patients with aneurysmal subarachnoid hemorrhage in the Amazon patients

Paschoal, Eric Homero Albuquerque 24 August 2017 (has links)
Hemorragia subaracnoidea aneurismática (HSAa) é considerada causa importante de morte e de sequelas neurológicas. A taxa de mortalidade desta doença pode alcançar 50% nos primeiros dois meses após sangramento de aneurisma encefálico. Apesar dos avanços científicos da modernidade, o resultado do tratamento da HSAa não mudou nos últimos anos. O presente estudo avaliou o papel de 14 biomarcadores genéticos, incluindo o polimorfismo (SNP) do gene eNOS, em pacientes da Amazônia com HSAa, para verificar as alterações alélicas associadas ao risco de vasoespasmo encefálico e déficit neurológico tardio. Avaliou-se a ancestralidade desta amostra de pacientes em que se utilizou 48 marcadores para identificar possível etnia associada à predisposição ao VE. Investigou-se 14 biomarcadores genéticos no tocante à resposta inflamatória encefálica na HSAa. Foram avaliados 265 doentes que foram divididos em dois grupos: grupo I (pacientes com vasoespasmo encefálico) e grupo 2 (pacientes sem vasoespasmo). A média das idades foi 51 anos, havia 224 mulheres (84%) e 124 pacientes (46,79%) apresentaram vasoespasmo encefálico (VE). A maior incidência de VE ocorreu na idade entre 50 e 59 anos. Tabagismo e hipertensão arterial sistêmica foram os fatores de risco mais associados à VE. Aneurismas encefálicos de tamanho pequeno e médio predominaram nesta casuística. As escalas amarela e vermelha do VASOGRADE associaram-se ao risco de VE (p < 0,001). Não houve variação na distribuição ancestral entre os grupos estudados e o que ocorre na população brasileira saudável na região Amazônica. O gene da eNOS com seus respectivos polimorfismos T-786C e 27VNTR4 correlacionaram-se com VE. Outros marcadores observados foram TP53, CASP8, ACE2, IL4 e XRCC1. O gene TP53 (modelo recessivo alelo 1) mostrou-se ser um fator protetor de VE, enquanto que genes com mutações INDEL CASP8 (modelo recessivo alelo 2) e o XRCC1 (modelo recessivo alelo 1) mostraram tendência ao desenvolvimento de VE com risco 2 vezes maior e 1,4 vezes maior que o grupo II (p < 0,001). Conclui-se que SNPs da eNOS se correlacionam com desenvolvimento de VE sintomático pós-HSAa. Este estudo também mostrou o papel dos marcadores inflamatórios na HSAa, o que auxiliaria na condução da terapia clínica. / Aneurysmal subarachnoid hemorrhage (aSAH) is a leading cause of premature death and neurological disability. It is considered as a devastating condition that accounts to 50% of mortality during the first two months after a hemorrhagic event. Despite foremost advances in the clinical management of post-aSAH patients, the rates of mortality and morbidity have not changed in recent years. This study appraised the role of 14 genetic biomarkers, including the eNOS polymorphism (SNP) between Amazon\'s patients with aSAH, as means to document how variant alleles are related to a higher disposition to cerebral vasospasm (CV) and delayed cerebral ischemia (DCI). 265 patients were evaluated and then divided into two clusters: Group I (with symptomatic CV) and group II (presenting no symptomatic CV). The median ages of patients were 51.61 years of age, 224 (84.52%) were women and 124 patients (46.97%) had symptoms of cerebral vasospasm (CV). Tobacco smoking and systemic arterial hypertension are the risk factors most associated to CV. In the course of this research, most aneurysms found were small and medium-sized. The score VASOGRADE yellow and VASOGRADE red presented a high risk of CV (p < 0.001). We established a panel of 48 ancestry informative markers for estimating which ethnicity could present a predisposition to CV. There was no variation in the ancestral distribution between study groups and healthy brazilian folk over the Amazon region. The eNOS gene with its polymorphisms T-786C and 27 VNTR4 were correlated to CV. Other markers were accomplished: TP53, CASP8, ACE2, IL4, and XRCC1. The TP53 gene (recessive genetic model allele 1) supporting evidence of the protective role to CV. Whilst other genes with INDEL mutation like as CASP8 (recessive model allele 2) and the XRCC1 (recessive model allele 1) indicated a propensity to spread out CV with odds 2-fold higher, and 1.414 times greater than group II (p < 0.001). It follows that eNOS SNPs correlate to a positive association with a syntomatic CV post-aSAH. Also, this study showed up the role of inflammatory markers at aSAH to a further educated therapeutic choice for a better clinical response
84

Severe cerebral emergency : aspects of treatment and outcome in the intensive care patient

Rodling Wahlström, Marie January 2009 (has links)
Severe Traumatic Brain Injury (TBI) and aneurysmal Subarachnoid Hemorrhage (SAH) are severe cerebral emergencies. They are common reasons for extensive morbidity and mortality in young people and adults in the western world. This thesis, based on five clinical studies in patients with severe TBI (I-IV) and SAH (V), is concentrated on examination of pathophysiological developments and of evaluation of therapeutic approaches in order to improve outcome after cerebral emergency. The treatment for severe TBI patients at Umeå University Hospital, Sweden is an intracranial pressure (ICP)-targeted therapy according to “the Lund-concept”. This therapy is based on physiological principles for cerebral volume regulation, in order to preserve a normal cerebral microcirculation and a normal ICP. The main goal is to avoid development of secondary brain injuries, thus avoiding brain oedema and worsened microcirculation. Study I is evaluating retrospectively 41 children with severe TBI, from 1993 to 2002. The boundaries of the ICP-targeted protocol were obtained in 90%. Survival rate was 93%, and favourable outcome (Glasgow Outcome Scale, score 4+5) was 80%. Study II is retrospectively analysing fluid administration and fluid balance in 93 adult patients with severe TBI, from 1998 to 2001.The ICP-targeted therapy used, have defined fluid strategies. The total fluid balance was positive day one to three, and negative day four to ten. Colloids constituted 40-60% of total fluids given/day. Severe organ failure was evident for respiratory insufficiency and observed in 29%. Mortality within 28 days was 11%. Study III is a prospective, randomised, double-blind, placebo-controlled clinical trial in 48 patients with severe TBI. In order to improve microcirculation and prevent oedema formation, prostacyclin treatment was added to the ICP-targeted therapy. Prostacyclin is endogenously produced, by the vascular endothelium, and has the ability to decrease capillary permeability and vasodilate cerebral capillaries. Prostacyclin is an inhibitor of leukocyte adhesion and platelet aggregation. There was no significant difference between prostacyclin or placebo groups in clinical outcome or in cerebral microdialysis markers such as lactatepyruvate ratio and brain glucose levels. Study IV is part of the third trial and focus on the systemic release of pro-inflammatory mediators that are rapidly activated by trauma. The systemically released pro-inflammatory mediators, interleukin-6 and CRP were significantly decreased in the prostacyclin group versus the placebo group. Study V is a prospective pilot study which analyses asymmetric dimethylarginine (ADMA) concentrations in serum from SAH patients. Acute SAH patients have cerebral vascular, systemic circulatory and inflammatory complications. ADMA is a marker in vascular diseases which is correlated to endothelial dysfunction. ADMA concentrations in serum were significantly elevated seven days after the SAH compared to admission and were still elevated at the three months follow-up. Our results show overall low mortality and high favourable outcome compared to international reports on outcome in severe TBI patients. Prostacyclin administration does not improve cerebral metabolism or outcome but significantly decreases the levels of pro-inflammatory mediators. SAH seems to induce long-lasting elevations of ADMA in serum, which indicates persistent endothelial dysfunction. Endothelial dysfunction may influence outcome after severe cerebral emergencies.
85

Απεικόνιση των ενδοκρανιακών αγγείων με την ψηφιακή αγγειογραφία (DSA) συγκριτικά με την CT αγγειογραφία (CTA) / Demonstration of the intracranial vessels using digital subtraction angiography (DSA) in comparison to CT angiography (CTA)

Καραμεσίνη, Μαρία 25 June 2007 (has links)
Η CT αγγειογραφία εγκεφάλου (CTA) είναι μέθοδος καθιερωμένη για την διερεύνηση και την θεραπεία των ενδοκρανιακών ανευρυσμάτων. Σκοπός της μελέτης μας ήταν η σύγκριση των ευρημάτων της ψηφιακής αγγειογραφίας (DSA) με αυτά της CTA και με τα χειρουργικά ευρήματα σε ασθενείς με οξεία υπαραχνοειδή αιμορραγία, καθώς επίσης και η αξιολόγηση της κλινικής χρησιμότητας της μεθόδου. Κατά την διάρκεια τριών ετών, 82 ασθενείς προσήλθαν με κλινική εικόνα και σημειολογία συμβατή με υπαραχνοειδή αιμορραγία. Η CTA έγινε αμέσως μετά την απλή CT, ενώ η DSA εντός των πρώτων 48 ωρών από την εισαγωγή. Όλα τα ανευρύσματα που ευρέθησαν με τις δύο μεθόδους υπεβλήθησαν σε χειρουργική αποκατάσταση ή ενδαγγειακό εμβολισμό. Σε όσους ασθενείς βρέθηκε αρνητικό αποτέλεσμα και με τις δύο μεθόδους, έγινε επαναληπτική DSA 15 ημέρες μετά το επεισόδιο με σκοπό την επιβεβαίωση της απουσίας ανευρύσματος. Οι CTA εξετάσεις καθώς και οι κλασσικές αγγειογραφίες μελετήθηκαν από μια ομάδα δύο ακτινολόγων για κάθε τεχνική, οι οποίοι έπρεπε να καταγράψουν την ύπαρξη ή μη ανευρύσματος, να περιγράψουν τα χαρακτηριστικά του και να αξιολογήσουν την μέθοδο. Χειρουργική ή και ενδαγγειακή θεραπεία έγινε σε 45 ασθενείς και ανευρέθησαν 53 ανευρύσματα. Χρησιμοποιώντας την CTA, ευρέθησαν 47 ανευρύσματα σε 42 ασθενείς. Η DSA ανίχνευσε 43 ανευρύσματα σε 39 ασθενείς. Η ευαισθησία της CTA για τον εντοπισμό όλων των ανευρυσμάτων με βάση το χειρουργικό/θεραπευτικό αποτέλεσμα ήταν 88,7%, η ειδικότητα 100%, η θετική προβλεπτική αξία (PPV) 100%, η αρνητική προβλεπτική αξία (NPV) 80,7% και η ακρίβεια 92,3%. Αντίστοιχα, η ευαισθησία της DSA ήταν 87,8%, η ειδικότητα 98%, η PPV 97,7%, η NPV 89,1% και η ακρίβεια 92,9%. Όσον αφορά στα ανευρύσματα ≥3 mm, η CTA είχε ευαισθησία που κυμαινόταν μεταξύ 93,3 έως 100%, ίση με αυτή της DSA. Η CTA εμφάνισε τα ίδια ποσοστά ευαισθησίας με αυτά της DSA σε ανευρύσματα ≥3 mm. Εμφάνισε επίσης 100% ποσοστό ανίχνευσης σε ανευρύσματα της πρόσθιας αναστομωτικής και του διχασμού της μέσης εγκεφαλικής αρτηρίας, ενώ μερικές εντοπίσεις όπως η οπίσθια αναστομωτική αρτηρία παραμένουν προβληματικές. 80 Κατά την διάρκεια της παρούσας μελέτης προσπαθήσαμε να δημιουργήσουμε μια τεχνική προσομοίωσης της διεγχειρητικής εικόνας των ραγέντων ενδοκρανιακών ανευρυσμάτων, με τη χρήση volume rendering techniques σε εικόνες που προκύπτουν από CT αγγειογραφία. Η τρισδιάστατη κατασκευή των εικόνων προέκυψε από την συνεργασία μιας ομάδας αποτελούμενης από τέσσερις ακτινολόγους, έναν νευροχειρουργό και έναν ιατρικό φυσικό. Το αποτέλεσμα αυτής της συνεργασίας ήταν η παραγωγή μιας εικόνας οριοθετημένης στο χώρο, με οδηγά σημεία που εύκολα μπορούσαν να αναπαραχθούν κατά την διάρκεια του χειρουργείου. Οι εικόνες χειρουργικής προσομοίωσης ενός ανευρύσματος είναι πιθανώς χρήσιμο εργαλείο για τον προεγχειρητικό σχεδιασμό των ενδοκρανιακών ανευρυσμάτων. / Cerebral CT angiography is an established method applied to both the detection and treatment planning of intracranial aneurysms. The aim of our study was to compare DSA to CTA findings and with the surgical results mainly in patients with acute SAH and to evaluate the clinical usefulness of CTA. During the last three years, 82 consecutive patients were admitted under clinical symptoms and signs suggestive of harbouring an intracranial aneurysm. CT angiography performed immediately afterwards the plain CT, while DSA was performed within the first 48 hours of admission. All aneurysms detected, were confirmed during surgery or endovascular embolization. Repeat DSA was performed in all patients having both the initial CTA and the DSA 15 days after the onset of symptoms negative. CT angiograms and conventional angiographies were studied by a consensus of two radiologists for each technique, who performed aneurysm detection, morphological features characterization and evaluation of the technique. Surgical or/and endovascular treatment was performed in 45 patients and 53 aneurysms were confirmed. Using 3D-CT angiography we detected 47 aneurysms in 42 patients. Conventional angiography depicted 43 aneurysms in 39 patients. The sensitivity of CTA for the detection of all aneurysms versus surgery was 88.7%, the specificity 100%, the positive predictive value (PPV) 100%, the negative predictive value (NPV) 80.7% and the accuracy 92.3%. Consequently, the sensitivity of DSA was 87.8%, the specificity 98%, the PPV 97.7%, the NPV 89.1% and the accuracy 92.9%. Considering the aneurysms ≥ 3 mm, CTA showed a sensitivity ranging from 93.3% to 100%, equal to that of DSA. Cerebral CT angiography has an equal sensitivity to DSA in the detection of intracranial aneurysms greater than 3 mm. It has also 100% detection rate in AcoA and MCA bifurcation aneurysms, while some locations like posterior communicating artery aneurysms remain problematic. The delineating features of each aneurysm are better depicted with CTA due to 3D visualization. The use of Digital Subtraction Angiography as a diagnostic tool can be limited in equivocal cases. A supplement to the above work is our effort to describe a technique for simulating the surgical view of ruptured intracranial aneurysms, using volume 82 rendering techniques in spiral CT angiography data. The 3D rendered images were assessed by a team consisted of four radiologists, one neurosurgeon and one medical physicist. The resultant ‘surgical view’ image was standardized in space using a three-dimensional coordinate system, which allowed for its reproduction in the operating theatre. The surgical views are easily reproducible and αποτελούν a useful tool for the surgical planning of intracranial aneurysms.
86

Quality systems to avoid secondary brain injury in neurointensive care

Nyholm, Lena January 2015 (has links)
Outcome after traumatic brain injury (TBI) depends on the extent of primary cell death and on the development of secondary brain injury. The general aim of this thesis was to find strategies and quality systems to minimize the extent of secondary insults in neurointensive care (NIC). An established standardized management protocol system, multimodality monitoring and computerized data collection, and analysis systems were used. The Uppsala TBI register was established for regular monitoring of NIC quality indexes. For 2008-2010 the proportion of patients improving during NIC was 60-80%, whereas 10% deteriorated. The percentage of ‘talk and die’ cases was &lt; 1%. The occurrences of secondary insults were less than 5% of good monitoring time (GMT) for intracranial pressure (ICP) &gt; 25 mmHg, cerebral perfusion pressure (CPP) &lt; 50 mmHg and systolic blood pressure &lt; 100 mmHg. Favorable outcome was achieved by 64% of adults. Nurse checklists of secondary insult occurrence were introduced. Evaluation of the use of nursing checklists showed that the nurses documented their assessments in 84-85% of the shifts and duration of monitoring time at insult level was significantly longer when secondary insults were reported regarding ICP, CPP and temperature. The use of nurse checklist was found to be feasible and accurate.  A clinical tool to avoid secondary insults related to nursing interventions was developed. Secondary brain insults occurred in about 10% of nursing interventions. There were substantial variations between patients. The risk ratios of developing an ICP insult were 4.7 when baseline ICP ≥ 15 mmHg, 2.9 when ICP amplitude ≥ 6 mmHg and 1.7 when pressure autoregulation ≥ 0.3. Hyperthermia, which is a known frequent secondary insult, was studied. Hyperthermia was most common on Day 7 after admission and 90% of the TBI patients had hyperthermia during the first 10 days at the NIC unit. The effects of hyperthermia on intracranial dynamics (ICP, brain energy metabolism and BtipO2) were small but individual differences were observed. Hyperthermia increased ICP slightly more when temperature increased in the groups with low compliance and impaired pressure autoregulation. Ischemic pattern was never observed in the microdialysis samples. The treatment of hyperthermia may be individualized and guided by multimodality monitoring.
87

Management ošetřovatelské péče u pacienta s nitrolebním krvácením / Management of nursing care of the patient with intracranial hemorrhage

LESÁKOVÁ, Barbora January 2018 (has links)
The diploma thesis deals with a problematic of management of the nursing care by a patient with intracranial hemorrhage. Most of the patients who survive intracranial hemorrhage stay permanently reliant on the care from others. That is why it is so important for this care to be as qualitative as possible and to have a fluent continuity. The aim of the thesis was to find out what is the role of a nurse by the patient with intracranial hemorrhage, then also find out, if the nurses know the warning signs of a worsening state of such patient, how do they cooperate with his/her family and what are the possibilities of the following care. In the empirical part of the diploma thesis, qualitative-quantitative research was used. For a complex view on a management of nursing care, the chosen technique of research was semi-structured questionnaire with patients with intracranial hemorrhage and non-standardized questionnaire with nurses who take care of these patients. For the quantitative part of the research, two hypotheses to two aims of the diploma thesis were set. Both hypotheses weren't proven by statistical methods. For qualitative research, four research questions were set. The respondents described the role of a nurse, especially in helping the patient, in rehabilitation and in also her role in educating the patient. Addressed respondents agreed on appropriate and swift reactions of the nurses in case the state of the patient starts to worsen. The cooperation of nurses and families is according to the patients without problems. It showed in the interviews with respondents, that there is a problem with insufficient awareness of the patients about the existing possibilities of following care. The outcome of the diploma thesis is a coherent educational material about nursing care by a patient with intracranial hemorrhage, which can serve to either the students or the nurses taking care of these patients.
88

Efeitos da hemorragia subaracnÃidea sobre a complacÃncia gÃstrica em ratos / The effect of subarachnoid hemorrhage on gastric compliance of anesthesized rats.

Aloisio Gazal Rocha 29 September 2015 (has links)
nÃo hà / A hemorragia subaracnÃidea (HSA) à a presenÃa de sangue no espaÃo subaracnÃideo, sendo capaz de aumentar a pressÃo intracraniana (PIC) a nÃveis que promovem alto grau de morbidade e mortalidade. Apresenta diferentes etiologias. Poucos estudos demonstram os efeitos da HSA sobre o trato gastrintestinal (TGI). Trabalhos cientÃficos prÃvios demonstraram alteraÃÃes na motilidade do TGI, especificamente sobre a complacÃncia gÃstrica (CG), em indivÃduos com hipertensÃo intracraniana (HIC), tornando-os impossibilitados de utilizar a via enteral, com consequente comprometimento da absorÃÃo de alimentos e medicamentos. O objetivo deste trabalho à avaliar os efeitos da HSA sobre a CG. Neste estudo foram utilizados ratos Wistar (300-350 g), sob os auspÃcios do COBEA (CEUA/UFC- Protocolo n 41/2013). A anestesia foi realizada com Ketamina/Xilasina (20-10 mg/Kg;ip). A hemorragia subaracnÃidea e secundariamente a hipertensÃo intracraniana foram obtidas por injeÃÃo intratecal de 0,2 ml de sangue autÃlogo no Grupo Teste (HSA) e lÃquor-sÃmile no Grupo Controle (Sham). Um grupo de animais foi submetido, anteriormente à induÃÃo, a tratamento cirÃrgico para estudo da participaÃÃo neural autonÃmica no controle da CG. No momento da induÃÃo da HIC/HSA os animais foram submetidos à canulaÃÃo do ventrÃculo cerebral para aferiÃÃo da PIC e da artÃria femoral para obtenÃÃo de dados hemodinÃmicos. ApÃs 72 h da induÃÃo, considerada como fase intermediÃria do processo inflamatÃrio da HIC os animais foram novamente anestesiados e submetidos à mensuraÃÃo da CG. Esta foi avaliada mediante sistema de reservatÃrio em âUâ acoplado a sistema de pletismografia (Ugo BasilleÂ). Simultaneamente foram mensuradas PIC, PA e FC. Os dados foram analisados por teste âtâ student, sendo considerados estatisticamente significativos com p < 0,05. Os resultados do modelo experimental utilizados no estudo de induÃÃo de hemorragia subaracnÃidea mostrou-se bom modelo de obtenÃÃo de hipertensÃo intracraniana crÃnica. A hipertensÃo intracraniana secundÃria à hemorragia subaracnÃidea, alÃm de produzir hipertensÃo e bradicardia diminuiu a complacÃncia gÃstrica nos ratos anestesiados; estando esta tanto mais diminuÃda quanto maior os nÃveis de pressÃo intracraniana. O prÃ-tratamento cirÃrgico com vagotomia subdiafragmÃtica nÃo modificou os valores da complacÃncia gÃstrica, enquanto que o prÃ-tratamento cirÃrgico com esplancnotomia e gangliectomia celÃaca preveniu a diminuiÃÃo da complacÃncia gÃstrica induzida por hipertensÃo intracraniana secundÃria à hemorragia subaracnÃidea. Palavras-Chave: complacÃncia gÃstrica; hemorragia subaracnÃidea; pressÃo intracraniana; rato. / In addition to increase in the intra cranial pressure, subarachnoid hemorrhage (SAH) is responsible for high morbidity grade and high mortality levels. Varied consequences are well documented, though little is known on the impact of SAH on the gastrointestinal tract (GIT). However, we have previously documented that intracranial hypertension reduces gastric compliance (GC), which may hamper enteric nutrition and efficiency of oral administered drugs in affected patients. We studied the effects of SAH on GC. After authorization by the COBEA(CEUA/UFC- Protocol n 41/2013), 130 male Wistar (300-350) rats were anesthetized (Ketamine/Xylazine (20-10 mg/Kg; ip) before being subjected to SAH or Sham protocol. Autologous blood was injected intra-theca, constituting the SAH protocol; while injection of a similar volume (0.2ml) of a lÃquor-sÃmile fluid formed the Sham-protocol. A brain ventricle was cannulated, to later verify increase in intra-cranial pressure (ICP) during GC experiments, while the femoral artery was utilized to measure simultaneous hemodynamic values: cardiac frequency (CF) and arterial pressure (AP). Another group of animals were operated upon to study the role of the autonomic nervous system in this phenomenon. After 72hs, the animals were anesthesized and submitted to GC measurement protocol; by pletysmography (Ugo BasilleÂ). Simultaneous values of ICP, CF and PA were recorded. Data was compared and analyzed by âtâ student test, with values p (where p < 0.05) considered statistically significant.
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Biomarcadores genéticos na hemorragia subaracnoidea aneurismática em pacientes da Amazônia / Genetic biomarkers in patients with aneurysmal subarachnoid hemorrhage in the Amazon patients

Eric Homero Albuquerque Paschoal 24 August 2017 (has links)
Hemorragia subaracnoidea aneurismática (HSAa) é considerada causa importante de morte e de sequelas neurológicas. A taxa de mortalidade desta doença pode alcançar 50% nos primeiros dois meses após sangramento de aneurisma encefálico. Apesar dos avanços científicos da modernidade, o resultado do tratamento da HSAa não mudou nos últimos anos. O presente estudo avaliou o papel de 14 biomarcadores genéticos, incluindo o polimorfismo (SNP) do gene eNOS, em pacientes da Amazônia com HSAa, para verificar as alterações alélicas associadas ao risco de vasoespasmo encefálico e déficit neurológico tardio. Avaliou-se a ancestralidade desta amostra de pacientes em que se utilizou 48 marcadores para identificar possível etnia associada à predisposição ao VE. Investigou-se 14 biomarcadores genéticos no tocante à resposta inflamatória encefálica na HSAa. Foram avaliados 265 doentes que foram divididos em dois grupos: grupo I (pacientes com vasoespasmo encefálico) e grupo 2 (pacientes sem vasoespasmo). A média das idades foi 51 anos, havia 224 mulheres (84%) e 124 pacientes (46,79%) apresentaram vasoespasmo encefálico (VE). A maior incidência de VE ocorreu na idade entre 50 e 59 anos. Tabagismo e hipertensão arterial sistêmica foram os fatores de risco mais associados à VE. Aneurismas encefálicos de tamanho pequeno e médio predominaram nesta casuística. As escalas amarela e vermelha do VASOGRADE associaram-se ao risco de VE (p < 0,001). Não houve variação na distribuição ancestral entre os grupos estudados e o que ocorre na população brasileira saudável na região Amazônica. O gene da eNOS com seus respectivos polimorfismos T-786C e 27VNTR4 correlacionaram-se com VE. Outros marcadores observados foram TP53, CASP8, ACE2, IL4 e XRCC1. O gene TP53 (modelo recessivo alelo 1) mostrou-se ser um fator protetor de VE, enquanto que genes com mutações INDEL CASP8 (modelo recessivo alelo 2) e o XRCC1 (modelo recessivo alelo 1) mostraram tendência ao desenvolvimento de VE com risco 2 vezes maior e 1,4 vezes maior que o grupo II (p < 0,001). Conclui-se que SNPs da eNOS se correlacionam com desenvolvimento de VE sintomático pós-HSAa. Este estudo também mostrou o papel dos marcadores inflamatórios na HSAa, o que auxiliaria na condução da terapia clínica. / Aneurysmal subarachnoid hemorrhage (aSAH) is a leading cause of premature death and neurological disability. It is considered as a devastating condition that accounts to 50% of mortality during the first two months after a hemorrhagic event. Despite foremost advances in the clinical management of post-aSAH patients, the rates of mortality and morbidity have not changed in recent years. This study appraised the role of 14 genetic biomarkers, including the eNOS polymorphism (SNP) between Amazon\'s patients with aSAH, as means to document how variant alleles are related to a higher disposition to cerebral vasospasm (CV) and delayed cerebral ischemia (DCI). 265 patients were evaluated and then divided into two clusters: Group I (with symptomatic CV) and group II (presenting no symptomatic CV). The median ages of patients were 51.61 years of age, 224 (84.52%) were women and 124 patients (46.97%) had symptoms of cerebral vasospasm (CV). Tobacco smoking and systemic arterial hypertension are the risk factors most associated to CV. In the course of this research, most aneurysms found were small and medium-sized. The score VASOGRADE yellow and VASOGRADE red presented a high risk of CV (p < 0.001). We established a panel of 48 ancestry informative markers for estimating which ethnicity could present a predisposition to CV. There was no variation in the ancestral distribution between study groups and healthy brazilian folk over the Amazon region. The eNOS gene with its polymorphisms T-786C and 27 VNTR4 were correlated to CV. Other markers were accomplished: TP53, CASP8, ACE2, IL4, and XRCC1. The TP53 gene (recessive genetic model allele 1) supporting evidence of the protective role to CV. Whilst other genes with INDEL mutation like as CASP8 (recessive model allele 2) and the XRCC1 (recessive model allele 1) indicated a propensity to spread out CV with odds 2-fold higher, and 1.414 times greater than group II (p < 0.001). It follows that eNOS SNPs correlate to a positive association with a syntomatic CV post-aSAH. Also, this study showed up the role of inflammatory markers at aSAH to a further educated therapeutic choice for a better clinical response
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Retrospektive Analyse zum Outcome von Patienten mit aneurysmaler Subarachnoidalblutung im Klinikum Chemnitz

Minasyan, Ararat 13 March 2018 (has links)
Einleitung Die aneurysmale Subarachnoidalblutung und ihre Komplikationen stellen eine akut lebensbedrohliche Erkrankung dar. Aufgrund einer hohen Letalität und Morbidität sowie zahlreichen, nicht modifizierbaren Risikofaktoren und fehlenden eindeutigen Präventionsmaßnahmen bleibt diese Krankheit eines der aktuellen Themen der Neurochirurgie. Ziel Ziel dieser Studie ist der Vergleich der Behandlungsergebnisse von Patienten mit aneurysmaler SAB im Klinikum Chemnitz mit aktuellen Literaturdaten. Material und Methode In dieser Arbeit wurden die Daten von insgesamt 200 Patienten mit aneurysmaler Subarachnoidalblutung retrospektiv zusammengefasst. Es wurde eine Populationsanalyse zusammen mit einer Analyse der Korrelationen zwischen verschiedenen Ausgangs- und Verlaufsparametern mit dem allgemeinen Outcome und der Mortalität durchgeführt. Zusätzlich erfolgte eine Follow-up-Analyse der Mortalität und Morbidität bei 108 Patienten. Im statistischen Modell wurden eine Uni- und Bivariatanalyse sowie binäre und multinomiale logistische Regression angewendet. Kaplan-Meier-Kurven in Verbindung mit Cox-Regressionsanalysen wurden zur Beurteilung der Mortalität eingesetzt. Die Ergebnisse wurden mit Literaturdaten verglichen. Das Votum der Ethikkommission der TU Dresden liegt vor (EK 181052014 vom 15.09.2014). Ergebnisse Von 200 Patienten mit einem Durchschnittsalter von 52 J (20-82 J, Medianalter 51 ± 13,6 J) waren 69 Patienten männlich (34,5 %), 131 – weiblich (65,2 %). Das männlich : weiblich Verhältnis betrug 1:1,9. Der klinische Schweregrad der Patienten bei Aufnahme wurde durch die WFNS- und die HH-Skalen evaluiert. Zusätzlich wurden die BNI- und Fisher-Skalen zwecks Evaluation des radiologischen Schweregrades der aSAB eingesetzt. Die Patientendistribution anhand der WFNS-Skala war: WFNS °I – 42,0 %, WFNS °II – 10,0 %, WFNS °II – 16,5 %, WFNS °IV – 22,5%, WFNS °V – 9,0 %. Die Verteilung der Patienten durch die HH-Skala war vergleichbar. 14,5 % der Patienten hatten eine BNI 1, 41,5 % - BNI 2, 32,0 % – BNI 3, 10,5 % - BNI 4, 1,5 % - BNI 5 Blutung. Bei 5,5 % der Patienten lag eine Fisher 1, 10,5 %– Fisher 2, 28,0% - Fisher 3 und 56,0 % - Fisher 4 SAB vor. 77,5 % der Aneurysmata waren klein (<11mm), 18,5 % - groß (11-25mm), 4 % - Giant (>25mm). Die Aneurysmen war meist im Bereich der Acom (41,5 %) und MCA (36,5 %) lokalisiert. Insgesamt 94,5 % der Aneurysmen gehörten zur vorderen Zirkulation. Die primäre Mortalitätsrate betrug 14,5 %. 21,5% der Patienten hatten einen mRS von 0-1 bei Entlassung, 26,0 % - einen mRS 2-3, 38,0 % - einen mRS 4-5. Die mittlere Follow-up-Dauer betrug 71,3 ± 43,2 Monate (Spannweite 2-168 Monate). Von den initial Überlebenden und im Follow-up eingeschlossenen Patienten sind 10,2 % im Verlauf verstorben. 48,1 % hatten einen mRS 0-1, 30,6% mRS 2-3, 11,1 % - mRS 4-5. Diskussion Das Outcome der Patienten mit einer aSAB trägt einen multifaktoriellen Charakter. Die wesentlichen Prädiktoren des Outcomes sind das Alter, der klinische und radiologische Schweregrad der Blutung, die Notwendigkeit der Versorgung eines posthämorrhagischen Hydrozephalus (temporäre und dauerhafte CSF-Ableitung), ein Vasospasmus, DIND und Entgleisun-gen im Serum-Natrium-Spiegel. Die Mortalitätsrate bei der primären Versorgung der Patienten mit einer aSAB in unserer Ko-horte ist um etwa 5 % niedriger als in der Literatur angegeben. Die Mortalitätsrate steigert sich allmählich während der ersten 3 Wochen. Sie wird im Wesentlichen vom Patientengeschlecht, dem klinischen und radiologischen Schweregrad der Blutung, der Notwendigkeit einer Akutversorgung eines aufgetretenen Hydrozephalus, einem Vasospasmus, Entgleisungen im Serum-Natrium-Spiegel sowie der Notwendigkeit einer CSF-Dauerableitung beeinflusst. Die Notwendigkeit einer CSF-Außenableitung bei Aufnahme korreliert mit einem schlechten Zustand der Patienten bei Entlassung und im Follow-up. Der Vasospasmus ist ein unabhängiger Prädiktor eines primär schlechten Outcomes und einer hohen Mortalität, zeigt sich aber als nicht signifikanter Faktor im Langzeit-Follow-up. Die Shuntpflicht ist bei Patienten mit Elektrolytentgleisungen, beidseitigen EVDs und DIND 3-4fach erhöht, beeinflusst jedoch nur die primäre Morbidität/Mortalität. Entgleisungen im Serum-Natrium-Spiegel zeigten sich als unabhängiger Prädiktor eines schlechten Outcomes und erhöhter Mortalität sowohl während des stationären Aufenthaltes, als auch im Langzeit-Follow-up. Die Notwendigkeit einer dekompressiven Kraniektomie wiederspiegelt sich in einem niedrigen BI der Patienten im primären Outcome und ist Prädiktor eines schlechten Outcomes und erhöhter Mortalität im Langzeit-Follow-up.:Verzeichnis der Abkürzungen 5 Kapitel 1: Grundlagen 6 1.1. Einleitung 6 1.2. Definition und Epidemiologie 7 1.3. Ätiologie 8 1.4. Pathogenese 9 1.5. Klinische Manifestation 11 1.6. Diagnostik 13 1.7. Therapie des rupturierten Aneurysmas 15 1.8. Therapie der Komplikationen nach aneurysmaler Subarachnoidalblutung 17 Kapitel 2: Methodik 19 2.1. Allgemein 19 2.2. Patientengut, Aufnahmezustand und Aneurysmacharakterisierungen 20 2.3. Therapie und Krankheitsverlauf 21 2.4. Outcome 22 2.5. Evaluation des aktuellen Zustandes der Patienten 23 2.6. Datenschutz und Statistisches Modell 24 Kapitel 3: Ergebnisse 25 3.1. Populationsanalyse, Ein- und Ausschlusskriterien 25 3.2. Schwere der Subarachnoidalblutung 26 3.3. Charakteristika der rupturierten Aneurysmen 27 3.4. Primäres Outcome 29 3.5. Outcome im Langzeit-Follow-up 31 3.6. Mortalität 33 3.7. Therapiedauer, Hydrozephalus, Elektrolytentgleisungen 36 3.8. DIND und Vasospasmus 38 3.9. Therapieassoziierte Komplikationen und Folgeoperationen 39 Kapitel 4: Diskussion 40 4.1. Mortalität 40 4.2. Outcome 43 4.3. Versorgungspflichtiger Hydrozephalus und Outcome 44 4.4. Vasospasmus, DIND, Elektrolytentgleisungen und Outcome 45 4.5. Limitationen der Studie 47 4.6. Schlussfolgerungen 48 Zusammenfassung 49 Summary 52 Literaturverzeichnis 55 Anlage 1 64 Anlage 2 66 Anlage 3 67 Anlage 4 68 Anlage 5 69 Anhang 1: Mortalitätsdynamik während des stationären Aufenthaltes 72 Anhang 2: Mortalitätsdynamik im Follow-up 74 Anhang 3: Die Abhängigkeit des Outcomes von verschiedenen Faktoren 75 Danksagung 78

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