Fisiología respiratoria: transporte de gases en sangre / Respiratory physiology: transport of oxygen and carbon dioxide in the blood

La sangre normalmente transporta pequeñas cantidades de oxígeno (O2) disuelto en el plasma y altas cantidades combinadas en forma química con la hemoglobina. La presión parcial depende solo del oxígeno disuelto físicamente, lo que determina cuánto oxígeno se combinará con hemoglobina. La curva de disociación de la hemoglobina describe la reversibilidad de la reacción entre oxígeno y hemoglobina. Los factores habituales que aumentan o disminuyen la afinidad de la hemoglobina por el oxígeno son el pH, presión parcial de CO2, temperatura y 2,3 difosfoglicerato. La sangre también transporta grandes cantidades en forma de bicarbonato y bajas cantidades de CO2 disuelto en plasma y combinado con proteínas como compuestos carbamino. La desoxihemoglobina favorece la formación de compuestos carbamínicos y promueve el transporte del CO2 como bicarbonato uniéndose al hidrógeno proveniente de la disociación del ácido carbónico. A continuación se describe en forma detallada los mecanismos fisiológicos del transporte de gases en sangre.

Blood normally carries small amounts of oxygen dissolved in plasma and large amounts chemically combined with hemoglobin. Partial pressure of oxygen depends only on physically dissolved oxygen which determines how much oxygen will combine with hemoglobin. The oxygen-hemoglobin dissociation curve (or oxyhemoglobin dissociation curve) describes the reversibility of the reaction between oxygen and hemoglobin. The usual factors that increase or decrease the affinity of hemoglobin for oxygen are pH, CO2 partial pressure, temperature, and 2,3 diphosphoglycerate. Blood also carries large amounts of CO2 as bicarbonate and low amounts dissolved in plasma and combined with proteins as carbamino compounds. Deoxyhemoglobin favors the formation of carbamino compounds and promotes the transport of CO2 as bicarbonate by joining the hydrogen from the dissociation of carbonic acid. The physiological mechanisms of gas transport in blood are described in detail below.

Evaluation of acute cardiorespiratory and hemodynamic changes in perioperative intravenous antimicrobial applications in cats / [Avaliação das alterações cardiorespiratórias e hemodinâmicas agudas em aplicações pré-operatórias de antimicrobianos, pela via intravenosa, em gatos]

The metabolic peculiarities of felines favor an intoxication. Fifty healthy female cats were divided into five groups: PG (placebo group), G2 (cefazolin), G3 (ceftriaxone), G4 (enrofloxacin) and G5 (ampicillin) were used. The parameters evaluated were: total expired carbon dioxide (ETCO2), oxygen saturation in hemoglobin (SpO2), heart rate (HR), respiratory rate (RR), body temperature (BT), systolic, mean and diastolic blood pressure (SBP, mBP and DBP) by invasive method, at T0, 5 (T5), 10 (T10), 15 (T15), 20 (T20), 25 (T25) and 30 (T30) minutes after administration of the treatments. HR presented reduction in G2 compared to PG at all times, except T20, and in G4, T25 and T30 were lower than the T0 values (P<0.05). BT showed increase in the G3 at T0 and T5 and all groups showed reduction in the values of BT relative to T0 (P<0.05). ETCO2 increased in G2 and G5 at all times compared to PG (P<0.05) and there were no differences among the times within each group. It was concluded that ceftriaxone is safer for the prophylactic antimicrobial use in cats, however the other antimicrobials are also indicated, because all the parameters, in all groups, basically did not change over the study and when this occurs it remains in reference interval.(AU)

As peculiaridades metabólicas dos felinos favorecem quadro de intoxicação. Foram utilizadas 50 gatas saudáveis, que foram divididas em cinco grupos: GP (grupo placebo), G2 (grupo cefazolina), G3 (grupo ceftriaxona), G4 (grupo enrofloxacina) e G5 (grupo ampicilina). Os seguintes parâmetros foram avaliados: dióxido de carbono expirado (ETCO2), saturação de oxigênio na hemoglobina (SpO2), frequência cardíaca (FC), frequência respiratória (FR), temperatura corporal (T°C), pressão arterial sistólica,média e diastólica (PAS, PAM e PAD), pelo método invasivo, em 0 (T0), 5 (T5), 10 (T10), 15 (T15), 20 (T20), 25 (T25) e 30 (T30) minutos após a administração dos tratamentos. A FC apresentou redução no G2 em relação ao GP em todos os momentos, exceto no T20, e, no G4, o T25 e o T30 foram inferiores aos valores do T0 (P<0,05). A T°C apresentou aumento no G3 no T0 e no T5, e todos os grupos apresentaram redução nos valores da T°C em relação ao T0 (P<0,05). O ETCO2 apresentou aumento no G2 e no G5, em todos os momentos, em relação ao GP (P<0,05). Concluiu-se que a ceftriaxona é mais segura para uso profilático em gatos, entretanto os outros antibióticos também são recomendados, pois todos os parâmetros praticamente não se modificaram e, quando alterados, mantiveram-se dentro dos padrões de referência.(AU)

Obtención de plasma rico en plaquetas (PRP) en el Laboratorio de Terapia Celular para uso como herramienta terapéutica en medicina regenerativa / Obtaining platelet rich plasma (PRP) in the Cell Therapy Laboratory for use as a therapeutic tool in regenerative medicine

Platelet rich plasma (PRP) is used to speed up tissue repair. Despite its widespread use, the therapeutic application of PRP generates controversies in clinical results due to the variability in methods of obtaining the different preparations and differences between the components of different types of PRP, so it's recommended to mention the type of platelet preparation used. In this article, we describe technical and biologics characteristics of our platelet product, and we compare them to different commercial preparations described in order to validate their clinical use. Our results determine that the preparation can be considered a platelet rich plasma with biological activity in vivo and in vitro, which supports its use as a valid therapeutic tool, alternative to products currently available in Regenerative Medicine. (AU)

Concordancia diagnóstica del sistema de graduación Chisholm Mason y Focus Score en la sialoadenitis linfocítica focal como aproximación al síndrome de Sjögren / Diagnostic agreement of the Chisholm Mason and Focus Score grading system in focal lymphocytic sialadenitis in patients with dry symptoms

RESUMEN Introducción: Existen diferentes sistemas de graduación para interpretar la biopsia de glándula salival menor (BGSM) en pacientes con síntomas secos. En la actualidad la metodología recomendada (Focus Score [FS]), aunque no se emplea de forma rutinaria, conlleva discrepancias diagnósticas. Objetivo: Determinar la concordancia de la lectura histopatológica de BGSM entre las técnicas FS y Chisholm Mason (CM) para el diagnóstico de sialoadenitis linfocítica focal en el hospital de San José, entre enero de 2017 y junio de 2018. Métodos: Estudio de concordancia. Se incluyeron BGSM de pacientes con síntomas secos. Se excluyó material no apto para el estudio, o con menos de 4 lóbulos o menos de 8 mm de área. Se clasificaron utilizando las técnicas FS y CM por 2 evaluadores independientes. Se evaluó el acuerdo interobservador, intraobsevador y global entre las pruebas mediante el coeficiente de Kappa de Cohen. Resultados: Se evaluaron 130 biopsias. Los valores K intraobservador entre FS y CM fueron 0,42 para el observador 1 y 0,23 para el observador 2. Los valores K del acuerdo interobservador fueron 0,47 para FS y 0,65 para CM. La concordancia entre los 2 sistemas de puntuación fue K de 0,13. Conclusiones: Se evidencia una probable sobreestimación de focos con CM, que resalta sus debilidades, y mayor precisión con FS. Por ende, la concordancia entre las 2 pruebas es débil. Es necesario un mayor esfuerzo para el uso del método estandarizado de lectura de BGSM con el FS para una correcta interpretación y beneficio en la clasificación de pacientes con síndrome seco.

ABSTRACT Introduction: There are different grading systems for interpreting the minor salivary gland biopsy (MSGB) in patients with dry symptoms (Sicca). The recommended methodology is currently the Focus Score (FS), which, although not performed routinely, results in diagnostic discrepancies. Objective: To determine the concordance of the histopathological reading of MSGB between the FS and Chisholm Mason (CM) techniques for diagnosis of focal lymphocytic sialadenitis at the San José Hospital between January 2017 and June 2018. Methods: Concordance study. MSGB of patients with sicca symptoms were included. Material not suitable for study and / or with less than 4 lobules and / or less than 8 mm of surface area was excluded. They were classified, using the FS and CM techniques, by two independent evaluators. The inter-observer, intra-observer, and overall agreement between the tests were evaluated using Cohen's Kappa coefficient. Results: A total of 130 biopsies were evaluated. The intra-observer K values between FS and CM were 0.42 for observer 1, and 0.23 for observer 2. The K values of the inter-observer agreement were 0.47 for FS, and 0.65 for CM. The concordance between the two scoring systems was K = 0.13. Conclusions: There is evidence of a probable over-estimation of foci with CM, highlighting its weaknesses and greater precision with FS technique, resulting in the weak concordance between the two tests. A greater effort is necessary for the use of the standardised MSGB FS reading method for a correct interpretation and benefit in the classification of patients with dry syndrome.

Estudio clínico y micológico de otomicosis en diabéticos: una serie de 17 casos / Clinical and mycological study of otomycosis in diabetics: series of 17 cases

RESUMEN Introducción: La otomicosis en pacientes inmunosuprimidos esta caracterizada por ser bilateral y ser causada por candida. Pocos estudios comparan las características micológicas encontradas en la microscopía directa y el cultivo. Objetivo: Identificar las características clínicas y micológicas de la otomicosis en pacientes diabéticos. Material y método: Estudio transversal en centro hospitalario de segundo nivel. Criterios de inclusión: pacientes diabéticos con diagnóstico clínico de otomicosis. Intervención: la muestra se examinó directamente bajo el microscopio y se cultivó. Resultados: Se incluyeron 17 pacientes, 10 mujeres y 7 hombres con una edad media de 47,5 años. Los síntomas predominantes fueron hipoacusia en 91,4% (n =16), prurito en 82,4% (n =14), otorrea en 76,5% (n=13)y otalgia en 70,6% (n =12). Afección bilateral se encontró en 47,1% (n =8). Estudio directo al microscopio mostró levaduras en 94,1% (n =16) y 5,9% mostró aspergillus (n =1). Cándida fue el género más comúnmente encontrado en los cultivos y en el examen directo microscópico con 94,1% (n =16) y Candida albicans la especie más común con 88,2% (n =15). Conclusión: Candida albicans es el agente etiológico más común en pacientes diabéticos con otomicosis. Su presentación clínica más frecuente es hipoacusia, prurito y otorrea. El examen directo identificó adecuadamente a los géneros fúngicos.

ABSTRACT Introduction: Otomycosis in immunocompromised patients is characterize by its bilateral course and the predominant etiologic agent is Candida. Few studies compare the mycological features between microscopic direct exam and culture. Aim: To identify the clinical and mycological characteristics of otomycosis in diabetic patients. Material and method: Transversal study. Secondary care center. Inclusion criteria: diabetic patients with clinical diagnosis of otomycosis. Intervention: Direct examination under a microscope of the ear sample and culture. Results: We included 17 patients, 10 women, 7 men with a mean age of 47.5 years. Symptoms were hearing loss 94.1% (n = 16), pruritus 82.4% (n =14) otorrhoea 76.5% (n =13) and otalgia 70.6% (n =12). Bilateral involvement was found in 47.1% (n =8). Direct microscopic study found 94.1% of yeast (n =16) and 5.9% of Aspergillus (n =1). Candida was the most common fungal genus in culture and microscopic exam with 94.1% (n =16) of cases and Candida albicans was the most common species in 88.2% (n =15) cases. Conclusion: Candida albicans is the most common etiologic agent in diabetic patients with otomycosis. Main symptoms were hearing loss, itching and otorrhea. Direct exam correctly identified the fungal genus.

Características clínicas y microbiológicas de las infecciones de piel y tejidos blandos por Staphylococcus aureus en niños de un hospital en Medellín durante los años 2013 a 2015 / Clinical and microbiological characteristics of skin and soft tissue infections caused by Staphylococcus aureus in children in a hospital in Medellin from 2013 to 2015

Resumen Introducción: El principal microorganismo implicado en las infecciones de piel y tejidos blandos (IPTB) es Staphylococcus aureus, con incremento en las cepas resistentes a meticilina en los últimos años. Objetivo: Identificar la frecuencia de S. aureus resistente a meticilina (SARM) en IPTB en niños que consultaron a un hospital de cuarto nivel en la ciudad de Medellín. Métodos: Estudio descriptivo, retrospectivo, a partir de la revisión de historias clínicas. Se incluyeron pacientes menores de 18 años con IPTB causadas por S. aureus que no cumplieran con criterios de enfermedad invasora. Resultados: La prevalencia de SARM en esta población fue de 31%. El principal diagnóstico fue absceso cutáneo (68%), seguido por infección de sitio quirúrgico (15%) y celulitis no purulenta (6%). Tenían alguna co-morbilidad 85% de los pacientes. Todos los aislados fueron sensibles a rifampicina y cotrimoxazol. Ocho por ciento de los aislados fueron resistentes a clindamicina. Se encontró mayor prevalencia de SARM en lactantes comparado con los mayores de 2 años (60 vs 23%, p = 0,0109). Conclusión: Ante la alta prevalencia de SARM en IPTB se recomienda incluir en el tratamiento empírico antimicrobianos con cobertura para estas cepas, principalmente para lactantes.

Background: Skin and soft tissue infections (SSTI) are very common in children and Staphylococcus aureus is the main agent, with an increase of methicillin resistant strains (MRSA) in recent years. Aim: To identify the frequency of MRSA in skin and soft tissue infections (SSTI) in children from a high complex hospital in Medellin, Colombia. Methods: This is a descriptive, retrospective study, information was obtained from medical records. We included patients younger than 18 years with SSTI due to S. aureus who did not meet criteria for invasive disease. Results: The prevalence of MRSA in this population was 31%. The main diagnosis was cutaneous abscess (68%), followed by surgical site infection (15%) and non-purulent cellulitis (6%). Eighty five percent of the patients had at least 1 comorbidity. All isolates were sensitive to rifampicin and cotrimoxazole and 8% of the isolates were resistant to clindamycin. There was a higher prevalence of MRSA in patients under 2 years compared to older (60 vs 23%, p = 0,0109). Conclusion: In view of the high prevalence of MRSA in SSTI, empirical treatment with adequate coverage for MRSA is recommended, especially for patients under 2 years of age.

Atresia anal com fístula retovaginal em ovino: relato de caso / Anal Atresia with rectovaginal fistula in sheep: case report

A atresia anal com fístula retovaginal, é considerada uma afecção congênita rara nos ovinos. Em virtude disso, buscou-se descrever o reparo cirúrgico e cuidados pós-operatórios em uma borrega que apresentava essa afecção. Nesse sentido, uma borrega, sem raça definida, de 25 dias de idade e pesando 7,2kg, apresentou sinais de distensão abdominal e defecação pela vulva. A afecção foi diagnosticada por meio do exame clínico e confirmada radiograficamente, constatando-se atresia anal do tipo III em associação com a fístula.(AU)

Atresia ani associated with rectovaginal fistula is considered a rare congenital anomaly in sheep. Therefore, the surgical correction and post-operative care of a lamb presenting atresia ani with rectovaginal fistula has been detailed in this case report. A 25-days old, mixed breed lamb, weighing 7.2 kg, showing signs of abdominal bloating, and stool passage through the vulva was admitted at our hospital. An atresia ani type III condition associated with rectovaginal fistula was diagnosed by clinical examination and confirmed by radiographic examination.(AU)

Hipodermoclisis como alternativa para la rehidratación en niños / Hypodermoclysis as an alternative to pediatric rehydration / Hipodermóclise como alternativa para a reidratação em crianças

La deshidratación es una de las principales causas de mortalidad en la población pediátrica en países en vía de desarrollo. Por ello, se han estudiado alternativas de manejo para la rehidratación oral, intravenosa e intraósea, de fácil aplicación y bajo costo. La hipodermoclisis es la técnica para la administración subcutánea de líquidos con el fin de prevenir o tratar la deshidratación leve o moderada; olvidada por muchos años debido a la falta de experiencia y protocolos bien estructurados. Recientemente resurge el interés en investigar e implementar esta técnica gracias a sus beneficios y menores riesgos frente a las otras opciones, entre las que se encuentran facilidad de aplicación, mantenimiento de la vía, comodidad del paciente y disminución de complicaciones por daño endotelial, demostrados en diferentes estudios como es el caso del Infuse Peds 1 y 2. Para favorecer la absorción subcutánea se puede implementar la hialuronidasa recombinante humana, enzima encargada de disolver el ácido hialurónico para alterar, temporalmente, la permeabilidad del tejido, que es el objeto de análisis dentro de estos estudios. En Colombia esta técnica aún no ha sido completamente difundida para aplicarla en la población pediátrica. Es imperativo divulgar opciones de manejo que sean efectivas y de bajo costo para la atención de las enfermedades más prevalentes. La hipodermoclisis cumple con estos objetivos y cuenta, además, con beneficios como la satisfacción de los padres y mejora índices de morbimortalidad infantil.

Dehydration is one of the main causes of mortality in pediatric population in developing countries. Thus, we have studied alternative measures that are low-cost and easy to administer for oral, intravenous, and intraosseuos rehydration. Hypodermoclysis is the technique for subcutaneous administration of liquids in order to prevent or treat mild or moderate dehydration. This method has been forgotten for many years due to the lack of experience and well-structured protocols. Recently, there has been increasing interest in researching and implementing this technique due to the benefits and lower risks compared to other options, including easy administration, pathway maintenance, patient comfort, and reduced complications due to endothelial damage, demonstrated in different studies, such as INFUSE-Peds I and II. Human recombinant hyaluronidase can be implemented in order to favor subcutaneous absorption; this enzyme is in charge of dissolving hyaluronic acid to temporarily alter the permeability of the tissue, which is the object of analysis of these studies. This technique has not been completely disseminated in Colombia to administer in pediatric population. It is imperative to divulge treatment options that are effective and low-cost to treat the most prevalent diseases. Hypodermoclysis meets these objectives and also has benefits such as parent satisfaction and improves indexes of infant morbidity and mortality.

A desidratação é uma das principais causas de mortalidade na população pediátrica em países em via de desenvolvimento. Por isso, se estudaram alternativas de manejo para a reidratação oral, intravenosa e intraóssea, de fácil aplicação e baixo custo. A hipodermóclise é a técnica para a administração subcutânea de líquidos com o fim de prevenir ou tratar a desidratação leve ou moderada; esquecida por muitos anos devido à falta de experiência e protocolos bem estruturados. Recentemente ressurge o interesse em investigar e implementar esta técnica graças a seus benefícios e menores riscos frente às outras opções, entre as que se encontram facilidade de aplicação, manutenção da via, comodidade do paciente e diminuição de complicações por dano endotelial, demostrados em diferentes estudos como é o caso do Infuse Peds 1 e 2. Para favorecer a absorção subcutânea se pode implementar a hialuronidase recombinante humana, enzima encargada de dissolver o ácido hialurônico para alterar, temporalmente, a permeabilidade do tecido, que é o objeto de análise dentro destes estudos. Na Colômbia esta técnica ainda não há sido completamente difundida para aplicá-la na população pediátrica. É imperativo divulgar opções de manejo que sejam efetivas e de baixo custo para a atenção das doenças mais prevalentes. A hipodermóclise cumpre com estes objetivos e conta, ademais, com benefícios como a satisfação dos pais e melhora índices de morbimortalidade infantil.

Perfil de producción de citoquinas en linfocitos T de sangre periférica de pacientes con poliposis nasal y asma bronquial en respuesta a la estimulación con enterotoxina estafilocócica B / Cytokine production profile in peripheral blood T lymphocytes from patients with nasal poliposis and bronchial asthma in response to staphylococcal enterotoxin B

Introducción: La poliposis nasal (PN) se presenta frecuentemente asociada a asma bronquial (AB). La enterotoxina estafilocócica B (SEB) jugaría un papel en su patogenia. No se ha estudiado si el perfil de citoquinas inducido por SEB en linfocitos T (LT) de pacientes con PNyAB difiere del de controles sanos. Objetivo: Comparar el perfil de citoquinas de LT de sangre periférica de pacientes con PN-AByde controles, estimulados con SEB o concanavalina A (ConA). Material y método: Células mononucleares de sangre periférica de 9 pacientes con PN-AB y de 6 controles se estimularon con SEB o ConA. El porcentaje LT CD4+ productores de interferón (IFN)-y, interleuquina (IL) IL-4, IL-5, IL-17 e IL-21 se determinó mediante citometrfa de flujo. Resultados: El grupo PN-AB presentó un menor porcentaje de LT productores de IL-5 que los controles al estimularse con SEB y con ConA. No hubo diferencia en las otras citoquinas estudiadas. Discusión: Nuestros resultados en sangre periférica difieren de lo descrito en tejido de pólipos nasales. Conclusión: Se sugiere que la respuesta inflamatoria de la PN se originaría localmente ya que los LT de sangre de pacientes con PN-AB no muestran una polarización hacia perfiles proinflamatorios con los estímulos utilizados.

Introduction: Nasal poliposis (NP) is frequently associated with bronchial asthma (BA) and its pathogenesis is still unknown. Staphylococcal enterotoxin B (SEB) has been implicated in the development of NP, however if the SEB-induced cytoklne profile of peripheral blood T lymphocytes (TL) of PN-BA patients differs from that of normal controls has not been studied. Aim: To compare the cytoklne profile of CD4+ TL from NP-BA and controls stimulated with SEB or concanavalin A (ConA). Material and method: Peripheral blood mononuclear cells from 9 NP-BA patients and from 6 controls were stimulated with SEB or ConA. The percentage of interferon (IFN)-y, interleukin {II) 11-4,11-5,11-17, and 11-21 producing TL was analyzed by flow cytometry Results: The percentage of SEB and ConA stimulated CD4+ IL-5-producing TLs was lower in the NP-BA group compared to the control group. There were no differences in the other cytokine-producing populations. Discussion: Unlike what is described in nasal polyp tissue, our findings show a diminished production of IL-5 by peripheral TL from the NP-AB group. Conclusion: A local sinonasal origin of the chronic inflammation is suggested since peripheral blood TL of NP-BA patients do not show a pro-inflammatory polarization with the tested stimuli.

Effects of carprofen administered by different routes to control experimental uveitis in dogs / Efeitos do carprofeno, aplicado por diferentes vias, no controle de uveítes experimentais em cães

Efficacy of carprofen, administered by different routes, was studied in experimental uveitis in dogs. Anterior chamber paracenteses was accomplished at two different moments (M0 and M1), with a five hour interval between them. At M0 and M1, 0.2mL of aqueous humor was collected and quantitation of total protein and prostaglandin E2 (PGE2) were determined. Four groups were formed (n=8), which received carprofen at the end of M0, by the following routes: subcutaneous (GIm), subconjunctival (GII), and topical (GIII). A fourth group that received no treatment was instituted (Control). Conjunctival histopathology of the GII animals was performed. In all groups, values of protein and PGE2 significantly enhanced at M1; however, they did not significantly change among groups at M1. Inflammatory exudate of acute character and mild hemorrhage were seen at histopathology after carprofen administration. Carprofen was unable to inhibit PGE2 synthesis and the protein influx to the anterior chamber by any of the tested routes. However, the reduction of 44 percent in protein levels (topical) suggests that the agent can be used by this route as an adjuvant to control uveitis in dogs.

Estudaram-se os efeitos do carprofeno, aplicado por diferentes vias, em uveítes experimentais em cães. Realizou-se paracentese de câmara anterior em dois momentos (M0 e M1), com intervalo de cinco horas entre si. Em M0 e M1, colheram-se 0,2mL de humor aquoso e determinaram-se as concentrações de proteína total e de prostaglandina E2 (PGE2). Constituíram-se quatro grupos (n = 8), que receberam carprofeno ao final de M0 pelas vias subcutânea (GI), subconjuntival (GII) e tópica (GIII). Um quarto grupo não recebeu tratamento (controle). Procedeu-se à avaliação histopatológica nos indivíduos do GII. Em todos os grupos, encontrou-se aumento significativo dos níveis proteicos e de PGE2 em M1. Não se observou diferença significativa, em M1, entre os grupos para nenhum dos parâmetros estudados. Exsudado inflamatório de caráter agudo e hemorragia discreta foram vistos à histopatologia após a aplicação do fármaco. O carprofeno foi ineficaz em inibir a síntese de PGE2 e o influxo de proteínas para a câmara anterior, por qualquer uma das vias testadas. Contudo, a redução de 44 por cento nos níveis de proteínas (via tópica), sugere que por esta via ele pode ser utilizado como adjuvante no controle da uveíte em cães.

Intraocular pressure and its correlation with blood gas parameters in crested caracaras (Caracara plancus) anesthetized with isoflurane and sevoflurane / Pressão intra-ocular e sua correlação com parâmetros hemogasométricos em caracarás (Caracara plancus) anestesiados com isofluorano e sevofluorano

The intraocular pressure (IOP) and its correlations with arterial carbon dioxide partial pressure (PaCO2) and arterial pH were studied in five crested caracaras (Caracara plancus) anesthetized with isoflurane (ISO) and sevoflurane (SEV). Baseline IOP values were measured in both eyes (M0). Brachial artery was previously catheterized to obtain blood gas and cardiorespiratory analysis. Anesthesia was induced with 5 percent ISO and maintained with 2.5 percent for 40 minutes. IOP measurements and blood samples were evaluated in different moments until the end of the procedure. After recovering, a second anesthesia was induced with 6 percent SEV and maintained with 3.5 percent. Parameters were evaluated at the same time points of the previous procedure. IOP reduced significantly (P= 0.012) from M0 at all time points and no significative changes were observed between ISO and SEV anesthesias. Correlation between IOP and PaCO2 and between PIO and blood pH were found only for SEV. IOP and blood pH decreased in parallel with IOP, whereas values of PaCO2 increased in caracaras anesthetized with isoflurane and sevoflurane.

Avaliou-se a pressão intra-ocular (PIO) e estimaram-se as correlações entre PIO e pressão de dióxido de carbono (PaCO2) e pH arterial de cinco caracarás (Caracara plancus), anestesiados com isofluorano (ISO) ou sevofluorano (SEV). Valores basais da PIO foram aferidos em ambos os olhos (M0). Cateterizou-se previamente a artéria braquial para obtenção de parâmetros hemogasométricos e cardiorrespiratórios. Anestesia foi induzida com ISO a 5V por cento e mantida por 40 minutos com 2,5V por cento. PIO e amostras de sangue foram avaliadas em diferentes momentos até o final do procedimento. Após recuperação, uma segunda anestesia foi realizada com SEV a 6 por cento e mantida com 3,5 por cento. Os parâmetros foram aferidos nos mesmos momentos estabelecidos previamente. A PIO decresceu significativamente (P=0,012) de M0 em todos os momentos e não houve diferença estatística entre ISO e SEV. Correlações significativas entre PIO e PaCO2 e entre PIO e pH sangüíneo foram observadas apenas para a anestesia com SEV. O pH sangüíneo decresceu paralelamente a PIO, enquanto a PaCO2 aumentou, em carcarás anestesiados com isofluorano e sevofluorano.

Avaliação macroscópica, microscópica e histomorfométrica do tecido cicatricial pós-cirúrgico de eqüinos submetidos a duas técnicas de neurectomia digital / Macroscopic, microscopic, and histomorphometric evaluation of post-operative scar tissue in horses submitted to two techniques for digital neurectomy

Avaliou-se macro e microscopicamente o tecido cicatricial pós-operatório de eqüinos submetidos a duas técnicas de neurectomia digital: guilhotina (TG) e stripping (TS). Decorridos 14 meses das cirurgias, foram colhidas 32 amostras de tecido cicatricial em quatro éguas, que tiveram os membros submetidos a ambas as técnicas. À macroscopia, verificaram-se as dimensões da cicatriz do coto proximal e a distância entre os cotos proximal e distal. À microscopia, foi quantificada a proporção de tecido nervoso regenerado por meio de histomorfometria. Não houve diferença nas dimensões do tecido cicatricial, contudo a distância entre cotos foi 5,6 vezes maior na TS (P<0,001). Histologicamente, observou-se a presença de tecido conjuntivo frouxo e denso, macrófagos e fibras nervosas delgadas em ambas as técnicas cirúrgicas. Estruturas nodulares, compostas por fascículos nervosos, foram visualizadas em 56,2 por cento (9/16) das amostras colhidas em nervos submetidos à TS. As porcentagens médias de tecido nervoso no tecido cicatricial foram de 0,31 por cento na TG e 2,6 por cento na TS (P<0,001). Concluiu-se que o retorno à sensibilidade nervosa deve demorar mais a ocorrer após a TS, devido à maior distância entre cotos. A maior proporção de tecido nervoso sugere que essa técnica favorece a regeneração nervosa.

The post-operative healed tissues in horses submitted to two digital neurectomy techniques, the guilhotine (GT) and the stripping (ST), were evaluated by macroscopy and microscopy. Fourteen months after surgery, 32 samples of scar tissue were collected from four mares that had the members experimentally submitted to both surgical techniques. By macroscopy, the dimensions of the scar tissue of the proximal stump and the distance between nerve stumps were taken. By microscopy, the proportion of nervous tissues in the scar tissue was quantified by histomorphometry. There were no differences between the scar tissue dimensions, but the distance between stumps was 5.6-fold greater in ST subjects. Histologically, connective tissue, macrophages, and thin nervous fibers were observed in scar tissue present in animals of both groups. Nodular structures composed by nervous fascicules were visualized in 56.2 percent (9/16) of the samples collected from the ST group. The mean percentage of the nervous tissue in scar tissue was 0.31 percent in GT samples and 2.6 percent in ST samples (P<0.001). After ST, a longer time to the return of the sensibility may occur due to the greater distance between stumps. However, greater proportion of nervous tissue in the scar tissue suggests that the use of this technique favors nervous regeneration.

Neurectomia digital em eqüinos: comparação das técnicas guilhotina e stripping / Digital neurectomy in horses: comparison of guillotine and stripping techniques

Compararam-se as dificuldades transcirúrgicas e as complicações pós-operatórias das técnicas guilhotina (TG) e stripping (TS) para a neurectomia digital em eqüinos. Sob anestesia com halotano, quatro éguas tiveram os nervos digitais de um dos membros torácicos e um dos pélvicos submetidos à TG, enquanto os nervos digitais dos membros colaterais foram submetidos à TS. Os tempos cirúrgicos médios de TG e TS foram semelhantes. O comprimento médio do fragmento do nervo removido foi três vezes maior em TS (P<0,001). Independente da técnica utilizada, houve perda total da sensibilidade nos talões de todos os membros dentro dos quatro primeiros meses da cirurgia. Após 14 meses, houve retorno da sensibilidade em 37 por cento dos membros em TG e 18,8 por cento em TS (P=0,06). Ao exame de palpação para identificação de neuromas dolorosos, houve episódios de sensibilidade discreta em um maior número de cotos nervosos proximais operados com TS, 53,6 por cento contra 6,4 por cento dos operados com TG (P=0,003). Ambas as técnicas foram satisfatórias por não apresentarem maiores complicações durante ou após a cirurgia. Considerou-se que TG apresentou menor potencial para produzir reinervação e neuromas dolorosos.

The surgical difficulties and the postoperative complications of two techniques for equine digital neurectomy, the guillotine (TG) and the stripping (TS), were evaluated. Four mares under halothane anesthesia were submitted to the TS in the digital nerves of a thoracic and a pelvic limbs, and TG in the contralateral limbs. The mean surgical times for TG and TS were similar. The mean transected nerve length was three times greater in TS (P<0.001). In both techniques, total lost of sensibility was observed in all heel bulbs during the first four months. After 14 months, sensibility returned to 37 percent limbs in treated by TG, and 18.8 percent in those treated by TS (P=0.06). Discreet painful sensation was identified by the response of digital palpation of the neuroma in a greater number of nerve stumps where TS was performed, 53.6 percent versus 6.4 percent of those operated by TG (P=0.003). No major complications were observed during or after surgery and both techniques were considered satisfactory. TG was considered with less potential to produce painful neuromas and reinnervation.

Rotura uterina espontánea en el primer trimestre del embarazo / Uterine rupture spontaneously in the first quarter of pregnancy

La rotura uterina es una complicación obstétrica infrecuente, pero potencialmente letal para la madre y el feto. Ocurre principalmente durante el segundo o tercer trimestre, asociada a factores de riesgo, entre los que destaca la cirugía uterina previa. Su aparición durante el primer trimestre es excepcional, constituyendo un desafío médico por su difícil diagnóstico diferencial y controversial manejo. Se presenta el caso de una paciente con rotura espontánea de útero grávido de 10 semanas de gestación, portadora de triple cicatriz anterior. El diagnóstico fue intraoperatorio, tras la descompensación hemodinámica de la paciente. El manejo incluyó el cierre primario de la lesión y observación posterior. Al sexto día se constata la muerte fetal y se efectúa el vaciamiento de la cavidad uterina. La falla de las medidas conservadoras obligó finalmente a realizar una histerectomía obstétrica. La histopatología informó placenta acreta.

Uterine rupture is an uncommon obstetric event, but still potentially lethal for the mother and the fetus. It presents mainly during the second or third trimester and is associated with several riskf actors, being a previous uterine scar the most important of them. Its presentation during the first trimester is exceptional, and it constitutes a medical challenge, because of its difficult differential diagnosis and controversial management. A case of a multiparous, previous triple scar woman is presented, with a spontaneous uterine rupture at 10 weeks of pregnancy. In this case the diagnosis was made during surgery, after the patient's hemodynamic decompensation. The management included primary closure of the lesion and observation; when fetal death was confirmed, dilatation and curettage of the cavity had to be performed. Because of the failure of conservative management, an obstetric hysterectomy was carried out. Histopathology reported placenta accreta.

Alergia al látex: avances en el desarrollo de inmunoterapias hipoalergénicas especificas / Latex allergy: advances in the development of specific hypoallergenic immunotherapies

This review provides a brief update about the strategies that have been developed for the hipoallergenic immunotherapy against latex allergens. Thus, recombinant mutants, chemically modified molecules, anti IgE monoclonal antibodies and T-cell epitope-based peptides have been used. Additionally, recent finds that show the importance of dendritic cells and their potential applicability to latex allergens are included.

Avances en inmunoterapia celular contra el melanoma maligno / Advances in cellular immunotherapy for malignant melanoma

An alternative strategy for cancer treatment is the manipulation of the immune system, denominated cancer immunotherapy. The immunotherapeutical use of cells of the immune system, like dendritic cells (DC), is being explored in different clinical protocols. Recently, we finalized a clinical phase I protocol, for the treatment of malignant melanoma, using DCs loaded with tumor lysates. Our results indicate that the subcutaneous application of DCs do not produce adverse effects. We also observed an increase of tumor specific T lymphocytes precursors in the blood, associated to hypersensitivity reactions (DTH) in 60% of the treated patients. In most cases, an stability in the disease was observed, although without a significant association between vaccination and survival. Additionally, therapies based on Interleukin-2 (IL-2) have been used with relative success in the treatment of some kind of tumors since 1985. However, problems associated to the toxicity of IL-2 still restrict its massive use. Our direct experience with the use of IL-2, indicates that low doses and its subcutaneous application, maintains the beneficial effects for patients, eliminating the adverse effects. Based on the accumulated evidence during last the five years, we decided to implement an optimized clinical protocol, which alternatively combines dendritic cells vaccines with the use of low doses of IL-2 for the reinforcement of the immunological system.

Experiencia preliminar en cirugías ambulatorias en el Servicio de Cirugía Pediátrica del Hospital Clínico Regional de Valdivia / Preliminar experience in ambulatory surgeries at Hospital Clínico Regional de Valdivia surgical paediatric service

Se presenta en forma preliminar la experiencia en cirugía ambulatoria de 300 pacientes en edades entre los 30 días y 15 años realizadas en el Servicio de Cirugía Infantil del Hospital Base de Valdivia, entre los años 1997 y octubre 2002, entendiendo por cirugía ambulatoria a la internación electiva, tratamiento y alta de pacientes durante el transcurso de un día hábil, excluyendo las cirugías menores efectuadas a pacientes occidentados o tratados en la Unidad de Emergencia. Se utilizaron criterios de selección como la edad (>30 días a <15 años), problemas anestésicos previsibles de acuerdo a la clasificación de estado físico de la Sociedad Americana de Anestesiología (status ASA I y II). Las patologías más frecuentemente resueltas mediante cirugía ambulatoria fueron las hernias inguinales, fimosis y testículos no descendidos. Las complicaciones no superaron el 1 por ciento y no obligaron a prolongar la estadía de los pacientes. La experiencia presentada sugiere continuar y extender esta práctica.

Malformación de la placa ductal en el desarrollo de la fibrosis hepática congénita. Un estudio inmunohistoquímico / Importance of the ductal plate malformation in the development of congenital hepatic fibrosis. An inmunohistochemical study

La fibrosis hepática congénita es una enfermedad autosómica recesiva caracterizada histológicamente por la presencia de tejido fibroconectivo en los espacios porta con numerosos conductos biliares de mediano calibre. Éste es un estudio inmunofenotípico de la placa ductal y su participación en la génesis de la fibrosis hepática congénita . Se estudiaron cuatro casos postmortem con diagnóstico histopatológico de fibrosis hepática congénita y cortes histológicos de hígados de embriones de ocho, nueve y 10 semanas de gestación. Se obtuvieron cortes histológicos y se utilizaron reacciones de inmunohistoquímica (citoqueratina 7, 8, 18, 19 y laminina). Los hepatocitos primitivos que rodean las ramas de la vena porta, muestran reactividad para citoqueratinas 7, 8, 18, 19 y laminina. La falta de remodelación de la placa ductal resulta en persistencia de conductos biliares embrionarios; estas anormalidades de la placa ductal pueden ser responsables de enfermedades congénitas de los conductos biliares intrahepáticos donde se incluye la fibrosis hepática congénita. Los resultados obtenidos demuestran que las células que forman placas ductales son positivas para citoqueratinas 8, 18, 19 y laminina a partir de la semana ocho de gestación y persiste su positividad en conductos biliares en la fibrosis hepática congénita. Estos hallazgos apoyan la hipótesis del desarrollo de la fibrosis hepática congénita por persistencia de la placa ductal.