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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.
1

Continuous thoracic paravertebral nerve blocks in pediatric patients

Bitarafan, Sara 08 April 2016 (has links)
Studies that evaluate the use of ultrasound-guided continuous paravertebral nerve blocks in pediatric patients are scarce, although the use of peripheral nerve blocks has indeed increased in popularity in the adult demographic. The present study aims to describe the epidemiology, safety and efficacy of ultrasound-guided continuous thoracic paravertebral nerve blocks as an everyday practice on a large scale in pediatric patients at a busy, academic, tertiary-care hospital. In all patients studied, a linear ultrasound transducer was used via the transverse in-line technique for catheter placement. Transducer configuration (frequency of oscillation and probe length) was varied based on individual patient factors, such as age, weight and body mass index. A descriptive, retrospective chart review of all patients who received a continuous paravertebral nerve block within a two-year time frame, from 10/2012 to 10/2014, was conducted, resulting in a sample size of 238 paravertebral catheters placed in 214 patients. In regards to patient demographics, the median age was 2 years (IQR 0.8 years - 12 years), with a range of 1 day to 18 years; and the average weight was 25.3 kg ± 23.6 kg, with a range of 1.8 kg to 113.7 kg. The median catheter duration was 3 days (IQR 2 days - 5 days), with 88.8% of catheters placed unilaterally, and 11.2% placed bilaterally. Median postoperative pain scores, intubation time, morphine equivalent consumption, and midazolam consumption were measured for all patients. The overall complication rate was 16.8% (n = 36 patients) with a minor catheter complication rate of 16.4% (n = 35). 6.1% (n = 13) of complications were due to catheter leakage, 4.7% (n = 10) due to catheter dislodgement, 2.8% (n = 6) due to skin irritation, 1.9% (n = 4) due to catheter occlusion and 0.9% (n = 2) due to minor bleeding at the site of catheter insertion. Only one patient experienced a major complication (0.5% of total patients), manifested as a self-resolving, 30-second seizure after a bolus administration of 2% chloroprocaine to manage postoperative pain. The patient was bag-mask ventilated for 60 seconds and the catheter was discontinued. No long-term sequelae were present in this case. Lastly, 98.1% (n = 210) of patients experienced sufficient pain coverage, yielding a failed block rate of 1.9% (n = 4). These results demonstrate safety and efficacy of ultrasound-guided transverse in-line continuous, thoracic paravertebral nerve block in pediatric patients, especially small infants and children. This technique provides an analgesic alternative to the thoracic epidural for postoperative pain treatment in pediatric patients.
2

Paravertebral Block: An Improved Method of Pain Control in Percutaneous Transhepatic Biliary Drainage

Culp, William, McCowan, Timothy C., DeValdenebro, Miguel, Wright, Lonnie B., Workman, James L., Culp, William C. 01 December 2006 (has links)
Background and Purpose: Percutaneous transhepatic biliary drainage remains a painful procedure in many cases despite the routine use of large amounts of intravenous sedation. We present a feasibility study of thoracic paravertebral blocks in an effort to reduce pain during and following the procedure and reduce requirements for intravenous sedation. Methods: Ten consecutive patients undergoing biliary drainage procedures received fluoroscopically guided paravertebral blocks and then had supplemental intravenous sedation as required to maintain patient comfort. Levels T8-T9 and T9-T10 on the right were targeted with 10-20 ml of 0.5% bupivacaine. Sedation requirements and pain levels were recorded. Results: Ten biliary drainage procedures in 8 patients were performed for malignancy in 8 cases and for stones in 2. The mean midazolam use was 1.13 mg IV, and the mean fentanyl requirement was 60.0 μg IV in the block patients. Two episodes of hypotension, which responded promptly to volume replacement, may have been related to the block. No serious complications were encountered. The mean pain score when traversing the chest wall, liver capsule, and upon entering the bile ducts was 0.1 on a scale of 0 to 10, with 1 patient reporting a pain level of 1 and 9 reporting 0. The mean peak pain score, encountered when manipulating at the common bile duct level or when addressing stones there, was 5.4 and ranged from 0 to 10. Conclusions: Thoracic paravertebral block with intravenous sedation supplementation appears to be a feasible method of pain control during biliary interventions.
3

Anestesia paravertebral torácica em cães / Thoracic paravertebral block in dogs

Villela, Ana Carolina Vasques 18 March 2016 (has links)
Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2016-08-09T18:49:21Z No. of bitstreams: 2 Tese - Ana Carolina Vasques Villela - 2016.pdf: 1850105 bytes, checksum: b1e0b35f32407fbefabe7f26e02c3604 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-08-10T11:48:54Z (GMT) No. of bitstreams: 2 Tese - Ana Carolina Vasques Villela - 2016.pdf: 1850105 bytes, checksum: b1e0b35f32407fbefabe7f26e02c3604 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-08-10T11:48:54Z (GMT). No. of bitstreams: 2 Tese - Ana Carolina Vasques Villela - 2016.pdf: 1850105 bytes, checksum: b1e0b35f32407fbefabe7f26e02c3604 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-03-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Thoracic paravertebral block (TPB) is a regional anesthesia technique which provides anesthesia and analgesia with hemodynamic stability, low incidence of complications and few contraindications. However, some techniques are still poorly studied in veterinary medicine due to difficulty in accessing specific nerves. The present study aimed at reviewing the thoracic anatomy, where TPB was conducted, determining values between reference points in order to implement this technique, assessing blockade’s quality and hemodynamic effects resulting from 2.5 mg/kg of bupivacaine 0.5% administration in dogs’ paravertebral space. Initially, structures involved when performing TPB were identified during an anatomical study in cadavers. In the second stage, eight healthy male or female dogs, mixed-breed, weighing 16.33 ± 4.04 kg, were submitted to TPB under general anesthesia with isoflurane. The blockage of thoracic T5, T6 and T7 nerves was performed with 2.5 mg/kg of bupivacaine 0.5%, guided by a neuro stimulator. Subsequently, the animals were anesthetized following the same protocol used in the previous stage for pulmonary-artery catheterization via the femoral vein, in order to assess hemodynamic effects of TPB. During TPB performance, the distances between the skin and the transverse process of thoracic vertebrae (STD) as well as the skin and paravertebral space (SPD) were obtained. Isoflurane supply was discontinued and analgesia evaluation was performed by pinprick test and hemostat pressure in conscious animals, after anesthesia recover. During hemodynamic evaluations the animals were kept anesthetized under spontaneous ventilation, while central venous pressure (CVP), cardiac output (CO), pulmonary artery pressure (PAP), pulmonary artery occlusion pressure (PAOP) and other cardiovascular variables were measured. Arterial and mixed venous blood were collected for blood gas analysis such as pH, oxygen partial pressure (PO2), carbon dioxide partial pressure (PCO2), bicarbonate (HCO3-), base excess (BE), anion gap (AG) and electrolytes such as sodium (Na+), potassium (K+), calcium (Ca2+) and chloride (Cl-), tissue oxygenation variables such as oxygen delivery (DO2), consumption (VO2) and oxygen extraction (OEF) were also calculated. Evaluations were made just before TPB (T0) and every 20 minutes in the next 80 minutes (T20, T40, T60, T80). Anatomical study revealed that some thoracic muscles’ innervation come from the brachial plexus. The average obtained for STD was 3.81 ± 1.07 cm and for SPD was 6.25 ± 0.93 cm. The anesthetic block was observed in 3.63±2.77 dermatomes during 250.25 ± 44.02 minutes. The variables CVP, CO, PAP, PAOP, DO2, OEF and PO2 in mixed-venous blood, increased significantly after bupivacaine administration. Similarly, PO2 from mixed venous blood as well as DO2 and OEF increased significantly during hemodynamic evaluations. TPB provided anesthesia in a limited region of the chest wall with clinically irrelevant hemodynamic effects, however this technique did not satisfactorily anesthetized all thoracic muscles’ layers so it should be used in combination with general anesthesia. / O bloqueio paravertebral torácico (BPT) é uma técnica de anestesia locorregional que fornece anestesia/analgesia no local da cirurgia com estabilidade hemodinâmica, baixa incidência de complicações e poucas contraindicações. No entanto, esta ferramenta ainda é pouco estudada na medicina veterinária devido à dificuldade de acesso aos nervos a serem bloqueados. O objetivo deste estudo foi rever a anatomia da região envolvida na realização do BPT, determinar as medidas entre os pontos de referência para execução desta técnica anestésica e avaliar a qualidade do bloqueio e as alterações hemodinâmicas decorrentes da administração de 2,5 mg/kg de bupivacaína a 0,5% no espaço paravertebral torácico de cães. Inicialmente, foi feito um estudo anatômico em cadáveres para identificar as estruturas envolvidas na execução do BPT. Na segunda etapa do estudo, oito cães saudáveis machos ou fêmeas, SRD, pesando 16,33 ± 4,04 kg, foram submetidos a anestesia geral com isofluorano para realização do BPT. O bloqueio dos nervos torácicos T5. T6 e T7 foi feito com 2,5 mg/kg de bupivacaína a 0,5%, com o auxílio de um neuroestimulador. Na terceira etapa, os mesmos animais foram anestesiados com isofluorano e, após introdução de um cateter de artéria pulmonar pela veia femoral, os animais foram submetidos ao BPT com 2,5 mg/kg de bupivacaína a 0,5% para avaliação das possíveis alterações hemodinâmicas. Foram obtidas as distâncias entre a pele e o processo transverso (DPt) e entre a pele e o espaço paravertebral torácico (DEp). Em seguida o fornecimento de isofluorano foi interrompido e a avaliação da analgesia foi realizada pelo pinçamento da pele com pinça hemostática. Para as avaliações hemodinâmicas os animais foram mantidos anestesiados com isofluorano sob ventilação espontânea e foram mensurados a pressão venosa central, (PVC), o débito cardíaco (DC), a pressão da artéria pulmonar (PAP) e a pressão da artéria pulmonar ocluída (PAPo), além de outras variáveis cardiovasculares indiretas calculadas. O sangue arterial e venoso misto foi coletado para avaliação do pH, pressão parcial de oxigênio (PaO2) e de dióxido de carbono (PCO2), bicarbonato (HCO3-), excesso de base (BE), ânion GAP (AG), eletrólitos sódio (Na+), potássio (K+), cálcio (Ca2+) e cloro (Cl-) e das variáveis de oxigenação tecidual como oferta (DO2), o consumo (VO2) e a extração de oxigênio (ERO2). As avaliações foram feitas imediatamente antes do BPT (T0) e, posteriormente, a cada 20 minutos (T20, T40, T60, T80). O estudo anatômico revelou que a inervação de alguns músculos da parede torácica é proveniente do plexo braquial. A DPt média foi de 3,81 ± 1,07 cm e a DEp média de 6,25 ± 0,93 cm. O bloqueio anestésico foi observado em 3,63 ± 2,77 dermátomos durante 250,25 ± 44,02 minutos. A PVC, o DC, a PAP e PAPo, a DO2, a ERO2 e a PaO2 no sangue venoso misto aumentaram significativamente após a administração da bupivacaína. O BPT promove anestesia em uma região limitada da parede torácica com alterações hemodinâmicas sem significância clínica, mas pode não anestesiar de forma satisfatória todas as camadas musculares da parede torácica, devendo ser utilizado em associação com a anestesia geral.
4

Estudo e desenvolvimento de fonte de fósforo-32 imobilizado em matriz polimérica para tratamento de câncer paravertebral e intracranial / Study and development of phosphorus-32 source immobilized in polymer matrix for paraspinal and intracranial cancer treatment

Benega, Marcos Antonio Gimenes 24 March 2015 (has links)
As últimas estimativas da Organização Mundial da Saúde mostram a ocorrência de 14,1 milhões de novos casos de câncer em 2012. Sendo que desses casos, 8,2 milhões virão a óbito. Os tumores paravertebrais e intracraniais, também chamados de cânceres do Sistema Nervoso Central, tem origem no cérebro, nervos cranianos e meninges. Uma nova modalidade de braquiterapia começou a ser usada nesta última década. Neste procedimento, placas poliméricas flexíveis, carregando fósforo-32, são colocadas próximas ou em contato ao tumor para o tratamento. Este tratamento apresenta vantagens em relação aos demais porque aplica uma alta taxa de dose no tumor poupando tecidos sadios. A produção destas placas ainda é pouco estudada, embora já existam resultados satisfatórios no seu uso para o tratamento dos cânceres do sistema nervoso central. Neste trabalho foram realizados estudos iniciais para a produção deste tipo de placas poliméricas para braquiterapia. Foram avaliadas as propriedades mecânicas e a capacidade de imobilização de material radioativo de duas resinas comercias, uma poliuretânica e outra epoxídica, com e sem presença de substrato de policarbonato. Os testes iniciais apontaram o uso da resina epoxídica como melhor alternativa e com o uso dela foram feitos os primeiros protótipos e testes. O uso do policarbonato como substrato não foi necessário em uma das metodologias, facilitando o procedimento, mas oferecendo uma barreira menor de segurança. Os ensaios de tração mostraram que a adição de solução ácida à resina epóxi alterou suas características mecânicas, mas houve uma pequena melhora em sua flexibilidade. Os testes de adesão evidenciaram uma melhor adesão da resina à face texturizada do policarbonato. A termogravimetria mostrou que a solução ácida adicionada a resina fica presa à estrutura mesmo com elevações de temperatura acima de 100°C. A resina epoxídica utilizada teve a capacidade de incorporar o material radioativo em forma de solução ácida e manter-se estanque após testes de esfregaço e imersão em líquido quente. De acordo com os resultados obtidos, a produção destas placas com resina epoxídica é possível e atende às normas internacionais de segurança contra vazamento de material radioativo para fontes utilizadas em braquiterapia. / The latest estimates of the World Health Organization show the occurrence of 14.1 million new cases of cancer in 2012. From these cases, 8.2 million will come to death. The paraspinal and intracranial tumors, also called central nervous system cancers, are originated in the brain, cranial nerves and meninges. A new brachytherapy modality began to be used in the last decade. In this procedure, flexible, polymeric plaques carrying phosphorus-32 are placed in contact or close to the tumor for treatment. This treatment has advantages over others because it applies a high dose rate in the tumor sparing healthy tissues. The production of these plaques is not well known, although there are satisfactory results in its use for the treatment of central nervous system cancers. This work carried out initial studies for the production of this type of polymer plaques for brachytherapy. The mechanical properties and immobilization capacity of radioactive material, from two commercial resins, epoxy and polyurethane, with or without the presence of polycarbonate as substrate were evaluated. Initial tests showed the use epoxy resin as the best alternative and the first prototypes and tests with use of it were made. The use of polycarbonate as a substrate was not required on one of the methodologies, facilitating the procedure but offering a lower security barrier. The tensile tests showed that addition of acid to the epoxy resin solution changed its mechanical properties, but there was a small improvement in flexibility. Adhesion tests showed better adhesion of the resin to the textured surface of the polycarbonate. The thermogravimetric analysis showed that the acid solution added to the resin structure is sealed even with temperature rises above 100°C. The epoxy resin used has the ability to incorporate the radioactive material in the form of acid solution and remain tight after wiping and immersion in hot liquid tests. According to the results, the production of these plaques with epoxy resin is possible and meets international safety standards for leakage of radioactive material in radioactive sources used in brachytherapy.
5

Estudo e desenvolvimento de fonte de fósforo-32 imobilizado em matriz polimérica para tratamento de câncer paravertebral e intracranial / Study and development of phosphorus-32 source immobilized in polymer matrix for paraspinal and intracranial cancer treatment

Marcos Antonio Gimenes Benega 24 March 2015 (has links)
As últimas estimativas da Organização Mundial da Saúde mostram a ocorrência de 14,1 milhões de novos casos de câncer em 2012. Sendo que desses casos, 8,2 milhões virão a óbito. Os tumores paravertebrais e intracraniais, também chamados de cânceres do Sistema Nervoso Central, tem origem no cérebro, nervos cranianos e meninges. Uma nova modalidade de braquiterapia começou a ser usada nesta última década. Neste procedimento, placas poliméricas flexíveis, carregando fósforo-32, são colocadas próximas ou em contato ao tumor para o tratamento. Este tratamento apresenta vantagens em relação aos demais porque aplica uma alta taxa de dose no tumor poupando tecidos sadios. A produção destas placas ainda é pouco estudada, embora já existam resultados satisfatórios no seu uso para o tratamento dos cânceres do sistema nervoso central. Neste trabalho foram realizados estudos iniciais para a produção deste tipo de placas poliméricas para braquiterapia. Foram avaliadas as propriedades mecânicas e a capacidade de imobilização de material radioativo de duas resinas comercias, uma poliuretânica e outra epoxídica, com e sem presença de substrato de policarbonato. Os testes iniciais apontaram o uso da resina epoxídica como melhor alternativa e com o uso dela foram feitos os primeiros protótipos e testes. O uso do policarbonato como substrato não foi necessário em uma das metodologias, facilitando o procedimento, mas oferecendo uma barreira menor de segurança. Os ensaios de tração mostraram que a adição de solução ácida à resina epóxi alterou suas características mecânicas, mas houve uma pequena melhora em sua flexibilidade. Os testes de adesão evidenciaram uma melhor adesão da resina à face texturizada do policarbonato. A termogravimetria mostrou que a solução ácida adicionada a resina fica presa à estrutura mesmo com elevações de temperatura acima de 100°C. A resina epoxídica utilizada teve a capacidade de incorporar o material radioativo em forma de solução ácida e manter-se estanque após testes de esfregaço e imersão em líquido quente. De acordo com os resultados obtidos, a produção destas placas com resina epoxídica é possível e atende às normas internacionais de segurança contra vazamento de material radioativo para fontes utilizadas em braquiterapia. / The latest estimates of the World Health Organization show the occurrence of 14.1 million new cases of cancer in 2012. From these cases, 8.2 million will come to death. The paraspinal and intracranial tumors, also called central nervous system cancers, are originated in the brain, cranial nerves and meninges. A new brachytherapy modality began to be used in the last decade. In this procedure, flexible, polymeric plaques carrying phosphorus-32 are placed in contact or close to the tumor for treatment. This treatment has advantages over others because it applies a high dose rate in the tumor sparing healthy tissues. The production of these plaques is not well known, although there are satisfactory results in its use for the treatment of central nervous system cancers. This work carried out initial studies for the production of this type of polymer plaques for brachytherapy. The mechanical properties and immobilization capacity of radioactive material, from two commercial resins, epoxy and polyurethane, with or without the presence of polycarbonate as substrate were evaluated. Initial tests showed the use epoxy resin as the best alternative and the first prototypes and tests with use of it were made. The use of polycarbonate as a substrate was not required on one of the methodologies, facilitating the procedure but offering a lower security barrier. The tensile tests showed that addition of acid to the epoxy resin solution changed its mechanical properties, but there was a small improvement in flexibility. Adhesion tests showed better adhesion of the resin to the textured surface of the polycarbonate. The thermogravimetric analysis showed that the acid solution added to the resin structure is sealed even with temperature rises above 100°C. The epoxy resin used has the ability to incorporate the radioactive material in the form of acid solution and remain tight after wiping and immersion in hot liquid tests. According to the results, the production of these plaques with epoxy resin is possible and meets international safety standards for leakage of radioactive material in radioactive sources used in brachytherapy.
6

Cocaine- and Amphetamine-Regulated Transcript-Immunoreactivity in the Rat Sympatho-Adrenal Axis

Dun, N. J., Dun, S. L., Kwok, E. H., Yang, J., Chang, J. K. 07 April 2000 (has links)
Distribution of cocaine- and amphetamine-regulated transcript-like immunoreactivity (CART-LI) was studied in the rat spinal cord, sympathetic ganglia and adrenal glands by immunohistochemical methods, utilizing a polyclonal antiserum raised against the CART peptide fragment 55-102. CART-LI was detected in nerve fibers and in basket-like terminals surrounding many postganglionic neurons of the superior cervical ganglion (SCG), stellate, paravertebral and prevertebral ganglia. Postganglionic neurons exhibited low or non-detectable levels of CART-LI. Surgical sectioning of the cervical sympathetic trunk for 6-7 days resulted in a nearly complete loss of CART-LI fibers and terminals in the SCG. In the adrenal gland, CART-LI nerve fibers formed a plexus underneath the capsule, some of which bifurcated and made a sharp turn toward the adrenal medulla, where clusters of chromaffin cells were intensely labeled. The detection of CART-LI in sympathetic ganglia and adrenal glands extends the previous observation of the presence of CART-LI in sympathetic preganglionic neurons and further supports the notion that CART peptide(s) may function as a signaling molecule in the sympatho-adrenal axis.
7

Comparaison entre l'infiltration para-vertébrale rétrolaminaire d'un mélange analgésique non-stéroïde et l'infiltration péridurale stéroïdienne chez les patients souffrant de douleurs radiculaires chroniques : une étude rétrospective

Nekoui, Alireza 06 1900 (has links)
No description available.
8

Caractérisation pharmacocinétique et pharmacodynamique de la lidocaïne avec ou sans adrénaline lors d’un bloc paravertébral du plexus brachial chez le chien

Choquette, Amélie 04 1900 (has links)
Au cours des vingt dernières années, l’anesthésie régionale est devenue, autant en médecine vétérinaire qu’humaine, un outil essentiel à l’élaboration de protocoles analgésiques péri-opératoires. Parmi l’éventail de techniques mises au point en anesthésie canine, le bloc paravertébral du plexus vertébral (PBPB) et sa version modifiée sont d’un grand intérêt pour toute procédure du membre thoracique, dans sa portion proximale. Toutefois, l’essentiel des données publiées à ce jour provient d’études colorimétriques, sans évaluation clinique, et peu d’information est disponible sur les techniques de localisation nerveuse envisageables à ce site. Notre étude visait à décrire une approche échoguidée du PBPB modifié, puis à caractériser ses paramètres pharmacocinétiques et pharmacodynamiques après administration de lidocaïne (LI) ou lidocaïne adrénalinée (LA). Huit chiens ont été inclus dans un protocole prospectif, randomisé, en aveugle et croisé, réparti sur trois périodes. L’impact pharmacodynamique du bloc effectué avec LI ou LA a été évalué régulièrement pour 180 min suivant son exécution. Le traitement à l’adrénaline n’a pas démontré d’impact significatif (P = 0,845) sur la durée du bloc sensitif, tel qu’évalué par un stimulus douloureux mécanique appliqué aux dermatomes ciblés. À l’opposé, l’atteinte proprioceptive évaluée par la démarche a été trouvée prolongée (P = 0,027) et le bloc moteur mesuré par le pic de force verticale (PVF) au trot sur la plaque de force s’est avéré plus marqué (PVF réduit; P = 0,007) sous LA. À l’arrêt comme au trot, le nadir de la courbe PVF-temps a été trouvé retardé (P < 0,005) et la pente ascendante de retour aux valeurs normales adoucie (P = 0,005). Parallèlement aux évaluations cliniques, des échantillons plasmatiques ont été collectés régulièrement afin de quantifier et décrire le devenir pharmacocinétique de la lidocaïne. Parmi les trois élaborés, un modèle bi-compartimental doté d’une double absorption asynchrone d’ordre zéro a finalement été sélectionné et appliqué aux données expérimentales. Sous LA, la Cmax a été trouvée significativement diminuée (P < 0,001), les phases d’absorption prolongées [P < 0,020 (Dur1) et P < 0,001 (Dur2)] et leurs constantes réduites [P = 0,046(k01) et P < 0,001 (k02)], le tout en concordance avec les effets proprioceptifs et moteurs rapportés. Bien que l’extrapolation du dosage soit maintenant théoriquement envisageable à partir du modèle mis en lumière ici, des études supplémentaires sont encore nécessaires afin d’établir un protocole de PBPB d’intérêt clinique. L’analyse sur plaque de force pourrait alors devenir un outil de choix pour évaluer l’efficacité du bloc dans un cadre expérimental. / Over the last decade, regional anaesthesia has become a gold standard for peri-surgical management in veterinary medicine. Among the many techniques developed for analgesia in dogs, the paravertebral brachial plexus block (PBPB) is of great interest when targeting the proximal half of the thoracic limb. Yet, most available data on this technique is based on colorimetric protocols rather than clinical evaluation, and there are very few published results for PBPB execution using nerve location techniques. Through this work, we wished to describe an ultrasound-guided approach of the PBPB and characterize its pharmacokinetic/ pharmacodynamic parameters when executed with either lidocaine alone (LI) or combined to adrenaline (LA). Eight dogs were included in a prospective, randomised, blinded, crossover protocol performed over three distinct periods. Pharmacodynamic impact of LI and LA was compared for 180 minutes after block administration. No significant difference (P = 0.845) was noted between treatments regarding length of the sensitive block, as evaluated regularly through a mechanical painful stimulus applied to selected dermatomes. On the opposite, gait examination showed a longer proprioceptive deficit using LA (P = 0.027). Motor block measured with dynamic force plate analysis showed a lower peak vertical force with LA than LI (P = 0.007). For both dynamic and static evaluations, nadir was clearly delayed (P < 0.005) and the ascending slope back to baseline significantly softened (P = 0.005) in the LA group. Throughout block execution and evaluation, blood samples were collected regularly in order to quantify and describe lidocaine kinetics. Models where developed and compared. A two-compartment model with dual zero-order absorption processes was selected as the best fit for our experimental data. Cmax proved to be significantly reduced with LA (P < 0.001), thus reducing potential toxicity. Absorption phase was prolonged [P < 0.020 (Dur1) and P < 0.001 (Dur2)] and zero-order absorption constant rates lowered [P = 0.046(k01) and P < 0.001 (k02)] following adrenaline addition, in accordance with the previously noted prolonged gait and motor effects. Though dosage extrapolation is now possible using the model developed and tested here, further studies would be needed to establish a PBPB protocol of more clinical interest. Then, force plate analysis could become a key tool for block quality assessment, as both dynamic and static measurements proved to be the reliable ways to collect ground reaction force (GRF) data.
9

Anatomic-Radiologic Correlation with High-Resolution 3D MR Imaging of the Human Cadaveric Sympathetic Chain

Guzylak, Vanessa 26 May 2023 (has links)
No description available.

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