Una Beca Mérito del Departamento de Asuntos de Veteranos y una subvención T32-HL098062 del NHLBI de los Institutos Nacionales de Salud apoya este trabajo. Queremos reconocer y agradecer el asesoramiento de Randolph H. Hasting, MD, Ph.D. y el asesoramiento y apoyo de la Unidad de Medicina Veterinaria de la VA Healthcare System San Diego.

1. Preparación de los animales <ol><li> Obtener los ratones que tienen más de 8 semanas y más de 20 g (ratones más pequeños pueden ser intubados por un experto). </li><li> Anestesia <ol><li> Inyectar ratones con 20 mg / kg, cada uno, de ketamina y xilazina por vía intraperitoneal como una preanestésica. (Esta dosis es insuficiente para anestesiar completamente el ratón, sino que facilita la transferencia, después de la intubación, la ventilación mecánica.) Sin embargo, el ajuste de las dosis puede ser necesario de acuerdo a la respuesta anestésica en consulta con el veterinario institucional.) </li><li> Inducir la anestesia en los ratones con 3,5% de isoflurano / oxígeno en una cámara de inducción de 90 a 120 seg. </li><li> Observe la frecuencia respiratoria con cuidado. Se debe reducir la velocidad progresivamente a no menos de 45 latidos por minuto. </li></ol></li></ol> 2. Preparación para la intubación <ol><li> Retire el ratón desde la cámara de inducción y pescuezo con fuerza. </li><li> Utilice unas pinzas finas acolchadas para gentLY extender la lengua de la boca. </li><li> Mantenga la extensión de la lengua mediante la celebración de la lengua entre los dos dedos y aplicando fuerza suave. </li><li> Tire del ratón hacia arriba sobre el espéculo del otoscopio con un movimiento vertical. </li><li> Mire a través del ocular del otoscopio mientras Scruffing firmemente y tire del ratón hacia arriba suavemente por la lengua y el pescuezo. </li><li> Busque cuidadosamente las cuerdas vocales. Ellos deben ser fácilmente visible en este momento. El aditus laryngis (la estructura de la abertura laríngea) debería ser relativamente blanco. No debe haber movimiento de las cuerdas con cada respiración. Si las cuerdas no se mueven o están mal visualizadas, gire ligeramente el animal y hiperextender suavemente el cuello. </li><li> Con la mano dominante, sostenga el 20 G, 1 en el catéter, con una longitud de 1 cm de la tubería PE10 se extiende a través de la punta del catéter, como un lápiz y la inserta en el lado del espéculo. La tubería de PE sirve como un estilete o candelilla. </li><li> Dirigir el tubi PE10ng (estilete) a través de las cuerdas vocales y avanzar el catéter de 20 G (sonda endotraqueal) en la tubería de PE hasta que el centro es a nivel del incisivo inferior. Eliminar este estilete rápidamente. </li><li> Saque con cuidado el animal fuera del espéculo y verificar la ubicación del tubo colocando al animal en un ventilador mecánico con 2% de isoflurano continua para mantener la anestesia general en todo el experimento. Visualice el aire expirado (burbujas) de pasar por una trampa de PEEP para confirmar la intubación. Aunque la intubación esofágica puede dar lugar a algunas burbujas, no será tan pronunciada o como consistente con la intubación endotraqueal. También, observar un trazado de presión de las vías respiratorias en caso de desviaciones negativas (Figura 1). Estos confirmar la colocación correcta del tubo. Como alternativa, coloque una pequeña cantidad de agua en el tubo de intravenosa, y conéctelo al tubo endotraqueal. Verificación de circulación hacia y desde el ratón con la respiración 2. En el caso de intubación esofágica, la prastreo resión revelará presiones significativamente más altos y no hay desviaciones negativas. Aunque tidal final de CO2 sería de gran ayuda, técnicamente esto sería muy difícil dado el pequeño volumen corriente (~ 200 l) y el equipo para hacer esto sería muy caro. Las técnicas simples descritas son totalmente suficiente y mucho menos caro. Si la anestesia isoflurano no está disponible, todos los procedimientos pueden llevarse a cabo usando ketamina 80-120 mg / kg en combinación con xilazina 10-20 mg / kg para la anestesia general. </li></ol> 3. Técnica alternativa: Laringoscopia directa con la Técnica otoscopio es fácilmente utilizados para otros fines, principalmente para la instilación directa de Sustancias de estudio en el pulmón. <ol><li> Inducir la anestesia en los animales con isoflurano solo para este procedimiento en 3.5% durante 90-120 segundos en la cámara de inducción. </li><li> Scruff el animal fuertemente en la base del cráneo y extender la lengua suavementecon unas pinzas finas. </li><li> La celebración de la lengua suavemente, tire el animal hacia arriba en el espéculo (sin modificar), hasta que el animal no se puede elevar aún más. </li><li> Las cuerdas vocales se pueden visualizar más a menudo por esta técnica por sí sola, pero giran el animal y la hiper-extendido el cuello para ponerlas en vista completa. </li><li> Avanzar en una pipeta de carga de gel que contiene el instilado a la glotis e inculcar el fluido. Debido a que el espéculo hace un sello con la hipofaringe el ratón aspirar cualquier líquido residual que no pasa por las cuerdas. Esto se comprueba fácilmente por el rhonchorous suena el ratón ahora hace cuando la respiración hasta que el líquido se distribuye completamente en los pulmones. </li><li> Como alternativa, conecte la tubería PE10 a una jeringa de 0,5 ml que contiene 50 l de fluido con un bolo de aire detrás del líquido. Avanzar el tubo de PE con cuidado a través de las cuerdas vocales de 0,5 cm y descargar el contenido en las vías respiratorias lentamente. Sin embargo, el trauma de vez en cuando a las vías respiratorias inferiores se produce ucantar esta técnica sin una mejor entrega de la muestra. </li></ol>

<ol>
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Los autores declaran que no tienen intereses financieros en competencia.

En este informe se describe una técnica sencilla y fiable para intubar ratones que es no traumática y puede ser utilizado en varias ocasiones en el mismo animal. Esta técnica se puede lograr con un simple laboratorio o equipos médicos que se pueden comprar por una suma modesta. La técnica de la laringoscopia directa, originalmente reportado por Hastings y colegas 4, también se puede utilizar para una variedad de propósitos, pero principalmente para entregar con precisión sustancias de ensayo en el tra...

El ratón de laboratorio ha suplantado a prácticamente todas las especies de mamíferos como el modelo principal de la biología y la biopatología. El ratón de laboratorio es la especie de mamífero más pequeño que se ha demostrado de forma clara y extensamente para ser de valor como modelo de enfermedades humanas y ha demostrado ser invaluable en los avances de nuestra comprensión de la biología humana y las enfermedades. El tiempo de gestación corto y sustancialmente menor costo ha permitido el desarrollo y estudio de ratones nulos y transgénicos como una herramienta común en la investigación biomédica. Sin embargo, el tamaño del ratón de laboratorio media (20-25 g) ha limitado su estudio en los estudios basados ​​fisiológicamente o quirúrgicamente y, en consecuencia, algunos investigadores estudian las especies de mamíferos más grandes. Un impedimento para el uso de ratones en estos estudios es la dificultad encontrada con técnicas de intubación que permitan mediciones fisiológicas o procedimientos quirúrgicos extensos bajo anestesia profunda. Traqueotomía 1 se ha utilizado como un estándar TEchnique lugar de intubación debido a la mayor facilidad de realización de esta técnica y habilidad modesta requerido. Sin embargo, la traqueostomía no es propicio para los estudios de cirugía crónicas o de recuperación; Por lo tanto, se limita a experimentos agudos. Traqueotomía también puede ser una variable de confusión en la investigación en las que la inflamación o los reflejos fisiológicos sensibles son importantes. Nuestro laboratorio ha probado la mayoría de las técnicas descritas por otros investigadores y los encontró inadecuada para una variedad de razones. La traqueotomía es demasiado traumático y provoca sangrado y la inflamación de las vías respiratorias. Mucho más problemático es que no se puede repetir factible. Muchas técnicas relativamente no invasivas que requieren una modesta inversión en equipos no son suficientemente fiables. Otras técnicas requieren equipos costosos que es difícil de justificar, sin saber si el equipo va a trabajar en una aplicación específica. Por lo tanto, tratamos de desarrollar una técnica no traumática que requiere no más tHan una modesta inversión en equipos especializados, podría llevarse a cabo de forma rápida y fiable, se podría repetir en modelos crónicos, y podría ser utilizado en un gran número de animales. Aquí mostramos una técnica de este tipo.

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			<td height="17" style="height:17px;width:411px;">Operating Otoscope Head</td>
			<td style="width:144px;">Welch Allyn</td>
			<td align="right" style="width:83px;">21700</td>
			<td style="width:69px;">&#160;$188.98</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Otoscope Handle</td>
			<td>Welch Allyn</td>
			<td align="right">71000</td>
			<td>&#160;$112.20</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Reuseable Speculum</td>
			<td>Welch Allyn</td>
			<td align="right">22002</td>
			<td>&#160;$ 3.98</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Fine Forceps</td>
			<td>Miltex</td>
			<td>18-779</td>
			<td>&#160;$107.18</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Small clamp stand to hold otoscope</td>
			<td></td>
			<td></td>
			<td></td>
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			<td></td>
			<td></td>
			<td></td>
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			<td height="17" style="height:17px;">Optional Equipment</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Isoflurane Vaporizer (multiple circuit with vacuum waste gas handling)</td>
			<td>Summit Medical</td>
			<td></td>
			<td align="right">$3,000</td>
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			<td height="17" style="height:17px;">Flexivent (Animal Ventilator)</td>
			<td>SCIREQ</td>
			<td></td>
			<td align="right">$35,000</td>
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		<tr height="17">
			<td height="17" style="height:17px;"></td>
			<td></td>
			<td></td>
			<td></td>
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			<td></td>
			<td></td>
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			<td height="17" style="height:17px;">Supplies</td>
			<td></td>
			<td></td>
			<td></td>
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		<tr height="17">
			<td height="17" style="height:17px;">Intravenous catheter (20 ga x 1 inch)</td>
			<td>BD</td>
			<td align="right">381233</td>
			<td>&#160;$&#160; 9.62</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Polyethylene tubing (PE10) (0.011 inch I.D., 0.024 inch O.D.) 100 ft</td>
			<td>Intramedic, Clay-Adams</td>
			<td align="right">427401</td>
			<td>&#160;$115.70</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Ketamine 100 mg/ml (10 ml bottle)</td>
			<td>Butler</td>
			<td align="right">23061</td>
			<td>&#160;$10.00</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Xylazine (100 ml bottle)</td>
			<td>Vedco</td>
			<td align="right">24105</td>
			<td>&#160;$20.00</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">Isoflurane (250 ml bottle)</td>
			<td></td>
			<td></td>
			<td>&#160;$15.00</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">vecuronium bromide 10 mg/10 ml</td>
			<td>Pfizer</td>
			<td>NDC 0069-0094-01</td>
			<td align="right">$15.00</td>
		</tr>
	</tbody>
</table>

endotracheal intubation in mice via direct laryngoscopy using an otoscope

Los ratones, tanto de tipo salvaje y transgénicos, son el modelo de mamíferos principal en la investigación biomédica en la actualidad. La intubación y la ventilación mecánica son necesarios para los experimentos con animales enteros que requieren cirugía bajo anestesia profunda o mediciones de la función pulmonar. La traqueotomía ha sido el estándar para la intubación de la vía aérea en estos ratones para permitir la ventilación mecánica. Intubación orotraqueal se ha informado, pero no ha sido utilizado con éxito en muchos estudios debido a la dificultad técnica sustancial o un requisito para un equipo altamente especializado y caro. Aquí mostramos una técnica de laringoscopia directa utilizando un otoscopio equipado con un espéculo 2,0 mm y el uso de un catéter intravenoso 20 G como un tubo endotraqueal. Hemos utilizado esta técnica extensamente y fiable que intubar y llevar a cabo una evaluación precisa de la función pulmonar en los ratones. Esta técnica ha demostrado ser seguro, esencialmente sin pérdida de animales en manos experimentadas. Por otra parte, esta técnicapuede ser utilizado para estudios repetidos de ratones en modelos crónicos.

La intubación con la técnica anterior es fiable y rápido. La colocación apropiada del tubo endotraqueal es más fácilmente verificado por la observación de burbujeo del gas espirado desde la rama de expiración sumergida de la del circuito del ventilador (por lo general en una trampa de PEEP) y desviaciones negativos en una presión de la vía aérea rastreo (Figura 1). Las desviaciones negativas en el seguimiento de la presión de las vías respiratorias son las más fiables. Otros han utilizado ...

Watch this Scientific Journal Video about Endotracheal Intubation in Mice via Direct Laryngoscopy Using an Otoscope at JoVE.com

Endotracheal Intubation in Mice via Direct Laryngoscopy Using an Otoscope

Hemos desarrollado un método simple, fiable, y relativamente barato para la intubación endotraqueal en ratones a través de la laringoscopia directa utilizando un otoscopio con un espéculo 2,0 mm. Esta técnica es atraumática y se puede utilizar para mediciones repetidas en experimentos crónicos. Nos resulta superior a la traqueotomía o previamente informó técnicas no quirúrgicas.

Intubación endotraqueal en ratones<em&gt; Vía</em&gt; La laringoscopia directa utilizando un otoscopio

Mice, both wildtype and transgenic, are the principal mammalian model in biomedical research currently. Intubation and mechanical ventilation are ...

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Endotracheal Intubation in Mice via Direct Laryngoscopy Using an Otoscope

30.8K vistas.  VA San Diego Healthcare System.  Hemos desarrollado un método simple, fiable, y relativamente barato para la intubación endotraqueal en ratones a través de la laringoscopia directa utilizando un otoscopio con un espéculo 2,0 mm. Esta técnica es atraumática y se puede utilizar para mediciones repetidas en experimentos crónicos. Nos resulta superior a la traqueotomía o previamente informó técnicas no quirúrgicas. 

Video: Endotracheal Intubation in Mice via Direct Laryngoscopy Using an Otoscope

Using Quantitative Real-time PCR to Determine Donor Cell Engraftment in a Competitive Murine Bone Marrow Transplantation Model

Murine bone marrow transplantation models provide an important tool in measuring hematopoietic stem cell (HSC) functions and determining genes/molecules that regulate HSCs. In these transplant model systems, the function of HSCs is determined by the ability of these cells to engraft and reconstitute lethally irradiated recipient mice. Commonly, the donor cell contribution/engraftment is measured by antibodies to donor- specific cell surface proteins using flow cytometry. However, this method heavily depends on the specificity and the ability of the cell surface marker to differentiate donor-derived cells from recipient-originated cells, which may not be available for all mouse strains. Considering the various backgrounds of genetically modified mouse strains in the market, this cell surface/ flow cytometry-based method has significant limitations especially in mouse strains that lack well-defined surface markers to separate donor cells from congenic recipient cells. Here, we reported a PCR-based technique to determine donor cell engraftment/contribution in transplant recipient mice. We transplanted male donor bone marrow HSCs to lethally irradiated congenic female mice. Peripheral blood samples were collected at different time points post transplantation. Bone marrow samples were obtained at the end of the experiments. Genomic DNA was isolated and the Y chromosome specific gene, Zfy1, was amplified using quantitative Real time PCR. The engraftment of male donor-derived cells in the female recipient mice was calculated against standard curve with known percentage of male vs. female DNAs. Bcl2 was used as a reference gene to normalize the total DNA amount. Our data suggested that this approach reliably determines donor cell engraftment and provides a useful, yet simple method in measuring hematopoietic cell reconstitution in murine bone marrow transplantation models. Our method can be routinely performed in most laboratories because no costly equipment such as flow cytometry is required.

Determining donor cell engraftment presents a challenge in mouse bone marrow transplant models that lack well-defined phenotypical markers. We described a methodology to quantify male donor cell engraftment in female transplant recipient mice. This method can be used in all mouse strains for the study of HSC functions.

Usando cuantitativa en tiempo real PCR para determinar quimerismo de células donantes en un modelo competitivo Trasplante de médula ósea murina

Murine bone marrow transplantation models provide an important tool in measuring hematopoietic stem cell (HSC) functions and determining genes/molecules ...

Investigación

Medicina

A Simple Method of Mouse Lung Intubation

A simple procedure to intubate mice for pulmonary function measurements would have several advantages in longitudinal studies with limited numbers or expensive animal. One of the reasons that this is not done more routinely is that it is relatively difficult, despite there being several published studies that describe ways to achieve it. In this paper we demonstrate a procedure that eliminates one of the major hurdles associated with this intubation, that of visualizing the trachea during the entire time of intubation. The approach uses a 0.5 mm fiberoptic light source that serves as an introducer to direct the intubation cannula into the mouse trachea. We show that it is possible to use this procedure to measure lung mechanics in individual mice over a time course of at least several weeks. The technique can be set up with relatively little expense and expertise, and it can be routinely accomplished with relatively little training. This should make it possible for any laboratory to routinely carry out this intubation, thereby allowing longitudinal studies in individual mice, thereby minimizing the number of mice needed and increasing the statistical power by using each mouse as its own control.

This paper describes a striaghforward and efficient method of intubating mice for pulmonary function measurements or pulmonary instillation, that allows the mice to recover and be studied at later times. The procedure involves an inexpensive fiberoptic light source that directly illuminates the trachea.

Un sencillo método de intubación ratón de pulmón

A  simple procedure to intubate mice for pulmonary function measurements would  have several advantages in longitudinal studies with limited numbers or  ...

Heterotopic Mucosal Engrafting Procedure for Direct Drug Delivery to the Brain in Mice

Delivery of therapeutics into the brain is impeded by the presence of the blood-brain barrier (BBB) which restricts the passage of polar and high molecular weight compounds from the bloodstream and into brain tissue. Some direct delivery success in humans has been achieved via implantation of transcranial catheters; however this method is highly invasive and associated with numerous complications. A less invasive alternative would be to dose the brain through a surgically implanted, semipermeable membrane such as the nasal mucosa that is used to repair skull base defects following endoscopic transnasal tumor removal surgery in humans. Drug transfer though this membrane would effectively bypass the BBB and diffuse directly into the brain and cerebrospinal fluid. Inspired by this approach, a surgical approach in mice was developed that uses a donor septal mucosal membrane engrafted over an extracranial surgical BBB defect. This model has been shown to effectively allow the passage of high molecular weight compounds into the brain. Since numerous drug candidates are incapable of crossing the BBB, this model is valuable for performing preclinical testing of novel therapies for neurological and psychiatric diseases.

A mouse model of human endoscopic skull base reconstruction has been developed that creates a semipermeable interface between the brain and nose using nasal mucosal grafts. This method allows researchers to study delivery to the central nervous system of high molecular weight therapeutics which are otherwise excluded by the blood-brain barrier when administered systemically.

Heterotópico mucosas Procedimiento La incorporación del trasplante de Drogas entrega directa al cerebro en ratones

Delivery of therapeutics into the brain is impeded by the presence of the blood-brain barrier (BBB) which restricts the passage of polar and high ...

An Improved Method for Rapid Intubation of the Trachea in Mice

Despite some anatomical and physiological differences, mouse models continue to be an essential tool for studying human lung disease. Bleomycin toxicity is a commonly used model to study both acute lung injury and fibrosis, and multiple methods have been developed for administering bleomycin (and other toxic agents) into the lungs. However, many of these approaches, such as transtracheal instillation, have inherent drawbacks, including the need for strong anesthetics and survival surgery. This paper reports a quick, reproducible method of intratracheal intubation that involves mild inhaled anesthesia, visualization of the trachea, and the use of a surrogate spirometer to confirm exposure. As a proof of concept, 8-12 week old C57BL/6 mice were administered either 2.0 U/kg of bleomycin or an equivalent volume of PBS, and both damage and fibrotic endpoints were measured post-exposure. This procedure allows researchers to treat a large cohort of mice in a relatively short period with little expense and minimal post-procedure care.

This article presents a rapid and simple method for administering bleomycin directly into the mouse trachea via intubation. Key advantages of this method are that it is highly reproducible, easy to master, and does not require specialized equipment or lengthy recovery times.

Un método mejorado para la rápida intubación de la tráquea en ratones

Despite some anatomical and physiological differences, mouse models continue to be an essential tool for studying human lung disease. Bleomycin toxicity ...

Inducing Acute Lung Injury in Mice by Direct Intratracheal Lipopolysaccharide Instillation

Airway administration of lipopolysaccharide (LPS) is a common way to study pulmonary inflammation and acute lung injury (ALI) in small animal models. Various approaches have been described, such as the inhalation of aerosolized LPS as well as nasal or intratracheal instillation. The presented protocol describes a detailed step-by-step procedure to induce ALI in mice by direct intratracheal LPS instillation and perform FACS analysis of blood samples, bronchoalveolar lavage (BAL) fluid, and lung tissue. After intraperitoneal sedation, the trachea is exposed and LPS is administered via a 22 G venous catheter. A robust and reproducible inflammatory reaction with leukocyte invasion, upregulation of proinflammatory cytokines, and disruption of the alveolo-capillary barrier is induced within hours to days, depending on the LPS dosage used. Collection of blood samples, BAL fluid, and lung harvesting, as well as the processing for FACS analysis, are described in detail in the protocol. Although the use of the sterile LPS is not suitable to study pharmacologic interventions in infectious diseases, the described approach offers minimal invasiveness, simple handling, and good reproducibility to answer mechanistic immunological questions. Furthermore, dose titration as well as the use of alternative LPS preparations or mouse strains allow modulation of the clinical effects, which can exhibit different degrees of ALI severity or early vs. late onset of disease symptoms.

Presented here is a step-by-step procedure to induce acute lung injury in mice by direct intratracheal lipopolysaccharide instillation and to perform FACS analysis of blood samples, bronchoalveolar lavage fluid, and lung tissue. Minimal invasiveness, simple handling, good reproducibility, and titration of disease severity are advantages of this approach.

Inducir lesión pulmonar aguda en ratones por instilación directa de lipopolisacárido intratraal

Airway administration of lipopolysaccharide (LPS) is a common way to study pulmonary inflammation and acute lung injury (ALI) in small animal models. ...

Repeated Orotracheal Intubation in Mice

The literature describes several methods for mouse intubation that either require visualization of the glottis through the oral cavity or incision in the ventral neck for direct confirmation of cannula placement in the trachea. The relative difficulty or the tissue trauma induced to the subject by such procedures can be an impediment to an investigator&#8217;s ability to perform longitudinal studies. This article illustrates a technique in which physical manipulation of the mouse following the use of a depilatory to remove hair from the ventral neck permits transcutaneous visualization of the trachea for orotracheal intubation regardless of degree of skin pigmentation. This method is innocuous to the subject and easily achieved with a limited understanding of murine anatomy. This refined approach facilitates repeated intubation, which may be necessary for monitoring progression of disease or instillation of treatments. Using this method may result in a reduction of the number of animals and technical skill required to measure lung function in mouse models of respiratory disease.

The goal of this article is to describe a refined method of intubation of the laboratory mouse. The method is noninvasive and, therefore, ideal for studies that require serial monitoring of respiratory function and/or instillation of treatments into the lung.

Intubación orotraqueal repetida en ratones

The literature describes several methods for mouse intubation that either require visualization of the glottis through the oral cavity or incision in the ...

Blind Endotracheal Intubation in Neonatal Rabbits

The newborn rabbit is a useful animal model for various pathologies and procedures. Airway management of the rabbit is complex due to its anatomical characteristics, which is further complicated in the case of the newborn. Of the different methods of advanced airway management, endotracheal intubation is less aggressive than tracheostomy, and is more feasible than supraglottic management given the lack of supraglottic devices of such a small size. As direct glottis visualization is very difficult in animals this size, this blind intubation model is presented as an effective alternative, especially for experiments requiring prolonged anesthesia. Using this method, we performed blind intubations with a 90% success rate.

We describe a technique of endotracheal intubation in newborn rabbits after esophageal catheterization with a gastric tube.

Intubación endotraqueal ciega en conejos neonatales

The newborn rabbit is a useful animal model for various pathologies and procedures. Airway management of the rabbit is complex due to its anatomical ...

Direct Drug Delivery to Kidney via the Renal Artery

There is a need for directed injections to enable increased and specific renal exposure for efficient evaluation of drug targets in the renal research field. Accumulation of drugs in certain organs may give rise to adverse and unwanted effects, depending on the nature of injectate. To minimize spillover and/or accumulation in other tissues, the herein described method directs the formulation into the renal artery bloodstream by inserting a catheter in the infra renal aorta, just below where it branches into the renal artery, resulting in the kidney as first reached organ and distributing of formulation throughout the kidney.
This manuscript provides a detailed description of the method, as well as its challenges and difficulties. It guides the experimenter to become skillful with this type of microsurgery that requires accuracy under sterile conditions. Speed is crucial for minimizing the ischemia and practicing the procedure will increase the chance of successful injections without adverse effects. By modulating the time between injection and reperfusion as well as the injected volume, the risk of spillover to other organs is mitigated. 
Note that this technique is suitable for single dosing strategies.

This manuscript describes a method for targeted delivery to a single kidney via a catheter placed in the infrarenal abdominal aorta in the mouse.

Entrega directa de medicamentos al riñón a través de la arteria renal

There is a need for directed injections to enable increased and specific renal exposure for efficient evaluation of drug targets in the renal research ...

Endotracheal Intubation Using a Flexible Intubation Endoscope as a Standardized Model for Safe Airway Management in Swine

Endotracheal intubation is often a basic requirement for translational research in porcine models for various interventions that require a secured airway or high ventilation pressures. Endotracheal intubation is a challenging skill,&#160;requiring a minimum number of successful endotracheal intubations to achieve a high success rate under optimal conditions, which is often unachievable for non-anaesthesiology researchers. Due to the specific porcine airway anatomy, a difficult airway can usually be assumed. The impossibility of establishing a secure airway can result in injury, adverse events, or death of the laboratory animal. Using a prospective, randomized, controlled evaluation approach, it has been shown that fiberoptic-assisted endotracheal intubation takes longer but has a higher first-pass success rate than conventional intubation without causing clinically relevant drops in oxygen saturation. This model presents a standardized regimen for endoscopically guided endotracheal intubation, providing a secured airway, especially for researchers who are inexperienced in the technique of endotracheal intubation via direct laryngoscopy. This procedure is expected to minimize animal suffering and unnecessary animal losses.

The use of pigs in research has increased in recent years. Nevertheless, pigs are characterized by difficult airway anatomy. By demonstrating how to perform endoscopically guided endotracheal intubation, the present protocol aims to further increase laboratory animals' safety to avoid animal suffering and unnecessary death.

Intubación endotraqueal con un endoscopio de intubación flexible como modelo estandarizado para el manejo seguro de las vías respiratorias en cerdos

Endotracheal intubation is often a basic requirement for translational research in porcine models for various interventions that require a secured airway ...

<meta charset="utf8"></head><body>Protocolo de intubación endotraqueal basado en traqueotomía para modelos de ratas que no sobreviven

Endotracheal Intubation via Tracheotomy and Subsequent Thoracotomy in Rats for Non-Survival Applications

Endotracheal intubation and subsequent ventilation are often basic requirements for translational research in rat models for various interventions that require controlled or high ventilation pressures or access to the thoracic cavity and organs. Conventional endoorotracheal intubation using the anatomically existing route through the mouth is well suited for survival experiments. However, this procedure poses some challenges, including generally higher levels of the required experience and technical skill, more advanced equipment, and greater time effort with relevant intubation failure rates and complications such as tracheal perforation, temporary systemic hypooxygenation, and relevant aerial leakage.
This manuscript, therefore, presents a detailed step-by-step protocol for endotracheal intubation through tracheotomy in non-survival rat models when guaranteed intubation success, constant oxygenation levels, high ventilation pressures, or open thoracotomy are required.
The protocol emphasizes the importance of meticulous surgical technique to ensure consistent and reliable outcomes, especially for researchers who are inexperienced or lack routine in the technique of endoorotracheal intubation via direct laryngoscopy. This procedure is, therefore, expected to minimize animal suffering and unnecessary animal losses.

<meta charset="utf8"></head><body>Intubación endotraqueal mediante traqueotomía y posterior toracotomía en ratas para aplicaciones no relacionadas con la supervivencia

Here we introduce a standardized procedure for endotracheal intubation via tracheotomy followed by thoracotomy in rats, aimed at enhancing the precision and reproducibility of non-survival applications requiring invasive ventilation and exposure of thoracic organs in in vivo rat models.

Intubación endotraqueal mediante traqueotomía y posterior toracotomía en ratas para aplicaciones no relacionadas con la supervivencia

Endotracheal intubation and subsequent ventilation are often basic requirements for translational research in rat models for various interventions that ...