The authors want to thank Dagmar Dirvonskis for her excellent technical support.

The experiments in this protocol were approved by the State and Institutional Animal Care Committee (Landesuntersuchungsamt Rheinland-Pfalz, Koblenz, Germany, TVA G21-1-080). The experiments were conducted in accordance with the ARRIVE guidelines. For this study, six healthy male German Landrace pigs aged 2-3 months and weighing 30-35 kg were used. The experimental timeline is summarized in Figure 1. The details related to all materials and instruments used in this protocol are listed in the Table of Materials.
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/66039/66039fig01.jpg" /> 
Figure 1: Experimental timeline. Baseline health measurements were taken after the preparation of the animal and a 30 min stabilization period. Endotoxemia was induced by LPS injection over 30 min and 0 h measurements were taken after another 30 min; after that, hourly measurements were continued for 4 h. Abbreviations: BLH = baseline healthy; LPS = lipopolysaccharide. <a href="https://www.jove.com/files/ftp_upload/66039/66039fig01large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
1. Animal preparation
<ol>
	<li>Keep the animals in their usual environment for as long as possible to minimize stress. Withhold food for 6 h prior to the administration of anesthesia, while allowing free access to water.</li>
	<li>Sedate the animals with an intramuscular injection of azaperone (3 mg&#8729;kg-1) and midazolam (0.5 mg kg-1) while still in their normal environment.</li>
	<li>Once the sedation takes effect, which typically occurs within approximately 15-20 min after administration, transport the pigs to the laboratory. 
	NOTE: It is crucial to ensure that continuous sedation is maintained throughout the transfer; depending on the regional legislature, this may require the permanent supervision of a veterinarian.</li>
	<li>Pay close attention to maintaining the normal body temperature of the pigs (~38 &#176;C) during transport. For instance, consider covering the animal with a blanket to prevent hypothermia. 
	NOTE: It is important to limit the transport time to not exceed the duration of sedation, which usually ranges from 30 min to 60 min.</li>
	<li>Following disinfection, establish an intravenous access by inserting a 22 G catheter in the auricular vein. Before proceeding with any further movement of the pig or induction of anesthesia, ensure that the catheter is securely fixed to prevent dislocation by any sudden movements.</li>
	<li>Continuously monitor the peripheral oxygen saturation using a sensor clipped to the tail or ear.</li>
</ol>
2. Anesthesia and mechanical ventilation
<ol>
	<li>Administer intravenous fentanyl (4 &#181;g kg-1) and propofol (3 mg kg-1) to induce anesthesia.</li>
	<li>Place the pig in a supine position.</li>
	<li>Administer atracurium (0.5 mg kg-1) as a muscle relaxant and immediately initiate non-invasive ventilation using a dog ventilation mask. Place the mask over the snout and apply firm pressure with the thumbs while pulling the lower jaw forward using the middle/ring finger. Set the ventilator to the following parameters: inspiratory oxygen fraction (FiO2 ) = 100%, tidal volume = 6-8 mL kg-1, Positive End Expiratory Pressure (PEEP) = 5 mbar, peak inspiratory pressure &#8804; 20 mbar, respiratory rate = 18-20 min-1.</li>
	<li>Maintain anesthesia by initiating a continuous infusion of a balanced electrolyte solution (5 mL kg-1 h-1), fentanyl (10 &#181;g kg-1 h-1), and propofol (6 mg kg-1 h-1).</li>
	<li>Perform endotracheal intubation using a standard endotracheal tube (ID 6-7 mm), a guidewire, and a laryngoscope equipped with a Macintosh Blade (size 4).
	<ol>
		<li>Have an assistant open the mouth and hold the tongue to the left side.</li>
		<li>Insert the Macintosh Blade until the epiglottis is visible. Then, lift the laryngoscope upwards to move the epiglottis ventrally and visualize the vocal cords. Occasionally, the epiglottis may stick to the soft palate; in this case, mobilize it by gently swiping sideways with the tube or a bougie.</li>
		<li>Carefully insert the endotracheal tube through the vocal cords and remove the inducer. If encountering difficulty, try rotating the tube without applying excessive force. If necessary, use a smaller tube. Once the tube is in place, inflate the cuff with 10 mL of air.</li>
	</ol>
	</li>
	<li>Connect the endotracheal tube to the ventilator and initiate ventilation. Confirm proper tube positioning by detecting end-expiratory CO2 and performing bilateral auscultation. Use the following ventilation settings: FiO2 = 40%, tidal volume = 6-8 mL kg-1, PEEP = 5 mbar, inspiration to expiration ratio = 1:2, respiratory rate = adjusted to achieve an end-tidal CO2 level of &#60;45 mmHg, typically 30-40 min-1 . 
	NOTE: If the tube has been placed incorrectly in the esophagus, air will inflate the stomach, causing a visible bulge. In such cases, immediately remove the tube, administer non-invasive ventilation for 1-2 min, and reposition the tube correctly.</li>
	<li>Insert a gastric tube to prevent reflux or vomiting. If insertion proves challenging, use the laryngoscope to obtain a better view of the esophageal entrance.</li>
</ol>
3. Instrumentation
<ol>
	<li>Place an arterial and a central venous line in the femoral artery and vein, respectively, for hemodynamic monitoring and intravenous volume therapy.</li>
	<li>Use bandages to retract and secure the hind legs, providing better access to the femoral vessels.</li>
	<li>Prepare all necessary materials prior to instrumentation. Fill all catheters with saline solution and ensure easy access to wires and catheters to minimize the need for multiple catheterization attempts and unnecessary blood loss.</li>
	<li>Apply an alcoholic disinfectant to the inguinal area and wipe it with a sterile swab. Repeat this process twice. Apply the disinfectant again without wiping and wait for 3 min. Place a sterile fenestrated drape over the inguinal area.</li>
	<li>Use ultrasound to identify the femoral blood vessels. Use an in-plane ultrasound-guided Seldinger&#39;s technique for catheterization to minimize tissue damage and blood loss.</li>
	<li>Visualize the femoral artery longitudinally. Puncture the artery with a syringe attached to the needle for continuous aspiration. Bright red, pulsating blood confirms arterial puncture. Remove the syringe and insert the prepared wire. Remove the needle while leaving the wire in place.</li>
	<li>Repeat the same procedure for the femoral vein. Venous puncture is confirmed by slow-flowing, dark red blood.</li>
	<li>Confirm the correct positioning of both wires by visualizing both femoral vessels using ultrasound.</li>
	<li>Use Seldinger&#39;s technique to insert the arterial introducer sheath first, followed by the venous introducer sheath. Confirm proper positioning through blood gas analysis of blood samples drawn from the two lines.</li>
	<li>Ensure that blood can be aspirated from all lines. Flush all lines with saline solution to prevent clot formation.</li>
	<li>Securely fix the lines to the skin using surgical sutures to prevent dislocation.</li>
	<li>Connect the arterial and central venous lines to transducers for the measurement of hemodynamic parameters.</li>
	<li>Insert a pulse contour cardiac output (PiCCO) catheter into the arterial introducer sheath and connect it to the arterial pressure transducer and temperature interface cable of the PiCCO monitor.</li>
	<li>Connect a Swan-Ganz catheter to a transducer.
	<ol>
		<li>While continuously measuring pressure, insert the catheter into the central venous introducer sheath. Inflate the balloon after approximately 30 cm, when a central venous pressure curve becomes visible.</li>
		<li>Slowly advance the catheter while monitoring the pressure curve. As the catheter enters the right ventricle, look for a pulse curve with a high systolic and low diastolic value. Further advancement of the catheter will result in a consistent systolic value and an increased diastolic value, indicating placement in the pulmonary artery.</li>
		<li>Fix the catheter in this position (usually between 50 and 70 cm). Connect the injectate temperature sensor of the PiCCO system to the proximal lumen of the Swan-Ganz catheter.</li>
	</ol>
	</li>
	<li>Shave the pig&#39;s forehead and apply the adhesive sensor electrode to measure Cerebral Regional Oxygen Saturation.</li>
	<li>After anesthesia induction and instrumentation, allow the animal to stabilize for 30 min or until hemodynamic parameters have stabilized before conducting baseline measurements and inducing endotoxemic shock.</li>
</ol>
4. Shock induction
NOTE: When working with LPS, always wear gloves, protective goggles, a mask, and a lab coat. Avoid direct contact with LPS.
<ol>
	<li>Prepare an LPS solution with a concentration of 100 &#181;g mL-1 by dissolving 5 mg of LPS in 50 mL of 0.9% NaCl.</li>
	<li>Obtain baseline hemodynamic measurements immediately before initiating LPS infusion.</li>
	<li>Administer a 150 &#181;g kg-1 dose of LPS over 30 min (equivalent to a continuous infusion rate of 300 &#181;g kg-1&#8729;h-1 for 30 min).</li>
	<li>After 30 min, reduce the infusion rate to 15 &#181;g&#8729;kg-1&#8729;h-1 for the remainder of the experiment.</li>
	<li>Continuously monitor hemodynamic parameters, including arterial and pulmonary arterial blood pressure, heart rate, and ventilation parameters. Monitor the body temperature continuously to maintain normothermia.</li>
</ol>
5. Treatment of hemodynamic instability
<ol>
	<li>When the mean arterial blood pressure falls below 60 mmHg, use PiCCO to measure cardiac index (CI), Global End-Diastolic Volume Index (GEDI), and Extravascular Lung Water Index (ELWI). Treat the low blood pressure according to the recommendations in the flow chart in Figure 2.
	<ol>
		<li>On the PiCCO monitor, press the thermodilution button (TD).</li>
		<li>Press the button for central venous pressure (CVP) input and enter the current CVP value.</li>
		<li>Press the Start button.</li>
		<li>When instructed to do so, inject 10 mL of cold saline solution into the injectate temperature sensor connected to the Swan-Ganz catheter. 
		NOTE: Do not inject anything else directly before or during PiCCO measurement as this would compromise the measurement.</li>
	</ol>
	</li>
	<li>After obtaining measurements for CI, GEDI, and ELWI, treat hemodynamic instability according to the flow chart in Figure 2. If Volume loading is recommended, rapidly infuse 200 mL of balanced electrolyte solution. If catecholamine therapy is recommended, increase the rate of norepinephrine infusion by 1 &#181;g kg-1 h-1.</li>
	<li>Repeat this process whenever the mean arterial blood pressure falls below 60 mmHg. In case of severe hemodynamic instability, opt for rapid escalation of therapy.</li>
</ol>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/66039/66039fig02.jpg" /> 
Figure 2: PiCCO-guided therapy of hemodynamic instability. After obtaining measurements for CI, GEDI, and ELWI, apply treatment according to the chart. This figure was adapted from the PiCCO user guidebook12. Abbreviations: PiCCO = pulse contour cardiac output; V+ = volume loading; cat = catecholamine therapy; V- = volume reduction; CI = cardiac index; GEDI = global end-diastolic volume index; ELWI = extravascular lung water index. <a href="https://www.jove.com/files/ftp_upload/66039/66039fig02large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
6. End of experiment and euthanasia
<ol>
	<li>Inject 0.5 mg of fentanyl intravenously. Wait 5 min. Inject 200 mg of propofol.</li>
	<li>Euthanize the pig with a rapid injection of 40 mL of 1 M potassium chloride via the central venous line.</li>
</ol>

Dosage-Dependent Induction of Endotoxemia in Pigs via LPS Infusion

<ol>
	<li>Vincent, J. -. L., Jones, G., David, S., Olariu, E., Cadwell, K. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Frequency+and+mortality+of+septic+shock+in+Europe+and+North+America:+a+systematic+review+and+meta-analysis.">Frequency and mortality of septic shock in Europe and North America: a systematic review and meta-analysis.</a> Critical Care. 23 (1), 196 (2019).</li><li>Reinhart, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recognizing+sepsis+as+a+Global+Health+Priority+-+A+WHO+Resolution.">Recognizing sepsis as a Global Health Priority - A WHO Resolution.</a> New England Journal of Medicine. 377 (5), 414-417 (2017).</li><li>Cecconi, M., Evans, L., Levy, M., Rhodes, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sepsis+and+septic+shock.">Sepsis and septic shock.</a> The Lancet. 392 (10141), 75-87 (2018).</li><li>Font, M. D., Thyagarajan, B., Khanna, A. 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S., Lowry, S. F., Calvano, S. E., Remick, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inflammation+and+the+host+response+to+injury+investigators+acute+inflammatory+response+to+endotoxin+in+mice+and+humans.">Inflammation and the host response to injury investigators acute inflammatory response to endotoxin in mice and humans.</a> Clinical and Diagnostic Laboratory Immunology. 12 (1), 60-67 (2005).</li><li>Dickson, K., Lehmann, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inflammatory+response+to+different+toxins+in+experimental+sepsis+models.">Inflammatory response to different toxins in experimental sepsis models.</a> International Journal of Molecular Sciences. 20 (18), 4341 (2019).</li><li>Bassols, A., Costa, C., Eckersall, P. D., Osada, J., Sabri&#224;, J., Tibau, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+pig+as+an+animal+model+for+human+pathologies:+A+proteomics+perspective.">The pig as an animal model for human pathologies: A proteomics perspective.</a> PROTEOMICS - Clinical Applications. 8 (9-10), 715-731 (2014).</li><li>Meurens, F., Summerfield, A., Nauwynck, H., Saif, L., Gerdts, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+pig:+a+model+for+human+infectious+diseases.">The pig: a model for human infectious diseases.</a> Trends in Microbiology. 20 (1), 50-57 (2012).</li><li>Ali, J., Cody, J., Maldonado, Y., Ramakrishna, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Near-infrared+spectroscopy+(NIRS)+for+cerebral+and+tissue+oximetry:+analysis+of+evolving+applications.">Near-infrared spectroscopy (NIRS) for cerebral and tissue oximetry: analysis of evolving applications.</a> Journal of Cardiothoracic and Vascular Anesthesia. 36, 2758-2766 (2022).</li><li>. Getinge Deutschland GmbH PiCCO Technologie Erweitertes h&#228;modynamisches Monitoring auf h&#246;chstem Niveau Available from: <a target="_blank" href="https://www.getinge.com/dam/hospital/documents/german/picco_haemodynamisches_monitoring_broschuere-de-non_us.pdf">https://www.getinge.com/dam/hospital/documents/german/picco_haemodynamisches_monitoring_broschuere-de-non_us.pdf</a> (2023)</li><li>Breslow, M. J., Miller, C. F., Parker, S. D., Walman, A. T., Traystman, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+vasopressors+on+organ+blood+flow+during+endotoxin+shock+in+pigs.">Effect of vasopressors on organ blood flow during endotoxin shock in pigs.</a> American Journal of Physiology-Heart and Circulatory Physiology. 252 (2), H291-H300 (1987).</li><li>Fink, M. P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Systemic+and+mesenteric+O2+metabolism+in+endotoxic+pigs:+effect+of+ibuprofen+and+meclofenamate.">Systemic and mesenteric O2 metabolism in endotoxic pigs: effect of ibuprofen and meclofenamate.</a> Journal of Applied Physiology. 67 (5), 1950-1957 (1989).</li><li>Lado-Abeal, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lipopolysaccharide+(LPS)-induced+septic+shock+causes+profound+changes+in+myocardial+energy+metabolites+in+pigs.">Lipopolysaccharide (LPS)-induced septic shock causes profound changes in myocardial energy metabolites in pigs.</a> Metabolomics. 14 (10), 131 (2018).</li><li>Park, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+fecal+peritonitis-induced+sepsis+in+a+porcine+model.">Characterization of fecal peritonitis-induced sepsis in a porcine model.</a> The Journal of Surgical Research. 244, 492-501 (2019).</li><li>Jarkovska, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Heart+rate+variability+in+porcine+progressive+peritonitis-induced+sepsis.">Heart rate variability in porcine progressive peritonitis-induced sepsis.</a> Frontiers in Physiology. 6, 412 (2015).</li><li>Kohoutova, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vagus+nerve+stimulation+attenuates+multiple+organ+dysfunction+in+resuscitated+porcine+progressive+sepsis.">Vagus nerve stimulation attenuates multiple organ dysfunction in resuscitated porcine progressive sepsis.</a> Critical Care Medicine. 47 (6), e461-e469 (2019).</li><li>Vintrych, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Modeling+sepsis,+with+a+special+focus+on+large+animal+models+of+porcine+peritonitis+and+bacteremia.">Modeling sepsis, with a special focus on large animal models of porcine peritonitis and bacteremia.</a> Frontiers in Physiology. 13, 1094199 (2022).</li><li>Stengl, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reduced+L-type+calcium+current+in+ventricular+myocytes+from+pigs+with+hyperdynamic+septic+shock.">Reduced L-type calcium current in ventricular myocytes from pigs with hyperdynamic septic shock.</a> Critical Care Medicine. 38 (2), 579-587 (2010).</li></ol>

The NIRS device was unconditionally provided by Medtronic PLC, USA, for experimental research purposes. Alexander Ziebart received a lecture fee from Medtronic PLC. None of the authors report any financial or other conflicts of interest. The manuscript was proofread and edited by ChatGPT&#174; (Python Software, Version: May 24, 2023).

We present a protocol for inducing experimental endotoxemia in pigs through LPS infusion, aiming to reliably induce changes commonly observed in sepsis and septic shock. Several critical steps need to be considered in this protocol. Adequate sedation of pigs prior to transport is crucial to prevent stress-induced elevation of catecholamine levels, which could potentially compromise the results. Intubation of pigs may pose challenges compared to humans due to the anatomical features of their elongated snouts. To address t...

Sepsis and septic shock rank among the leading causes of mortality in patients receiving intensive care treatment1,2,3. Sepsis arises when an infection triggers a dysregulated immune response resulting in multiorgan failure. It is characterized by life-threatening symptoms, including hemodynamic instability, respiratory distress, hepatic and renal failure, as well as cognitive impairment4,5. Septic shock represents a subset of sepsis with particularly severe symptoms that significantly increase mortality. These symptoms include persistent hypotension requiring vasopressor therapy and a serum lactate level exceeding 2 mmol&#8729;L-1&#160;4,5. Mortality rates in patients with septic shock have been estimated as high as 40%, even with hospital treatment1,3,5.
Gram-negative bacteria, such as Pseudomonas and Escherichia coli, often cause infections triggering this dysregulated immune response4. The underlying pathophysiological mechanisms are complex and not yet fully understood. One well-described aspect involves the activation of Toll-like receptors on immune cells by pathogen-associated molecular patterns (PAMPs), leading to the release of cytokines such as tumor necrosis factor-alpha (TNF&#945;) or Interleukin 1 (IL 1)4. One of these PAMPs is lipopolysaccharide (LPS), which constitutes a component of the cell membrane in gram-negative bacteria6. LPS has been employed in animal models to induce endotoxemia and endotoxemic shock7,8.
Animal models provide a controlled and standardized setting to develop and investigate novel treatment strategies. Due to its similar anatomy, immunological physiology, and comparable hemodynamic parameters, the pig model is particularly well-suited for studying the effects of endotoxemic shock9,10. Furthermore, standard medical equipment commonly used in human patients can be readily applied in pigs due to the similar size of their airways and blood vessels, facilitating instrumentation and hemodynamic monitoring.
With this protocol, we provide an experimental model for endotoxemic shock in pigs by intravenously infusing LPS derived from E. coli. To monitor the effects, we measured hemodynamic and pulmonary parameters, including arterial blood pressure, heart rate, peripheral oxygen saturation, pulmonary arterial pressure, and airway pressure. To evaluate the influence of endotoxemia on cerebral oxygen supply, we used near-infrared spectrometry (NIRS). With this method, the cerebral oxygen saturation can be evaluated via an adhesive electrode applied to the forehead11.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Atracurium Hikma 50 mg/5mL</td>
			<td>Hikma Pharma GmbH, Martinsried</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Azaperone (Stresnil) 40 mg/mL</td>
			<td>Lilly Deutschland GmbH, Bad Homburg, Germany</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>BD Discardit II Spritze 2, 5, 10, 20 mL</td>
			<td>Becton Dickinson S.A. Carretera, Mequinenza Fraga, Spain</td>
			<td>syringe</td>
			<td></td>
		</tr>
		<tr>
			<td>BD Luer Connecta&#160;</td>
			<td>Becton Dickinson Infusion Therapy, AB Helsingborg, Schweden</td>
			<td>3-way-stopcock</td>
			<td></td>
		</tr>
		<tr>
			<td>Curafix i.v. classics</td>
			<td>Lohmann &#38; Rauscher International GmbH &#38; Co. KG, Rengsdorf, Germany</td>
			<td>Cannula retention dressing</td>
			<td></td>
		</tr>
		<tr>
			<td>Datex Ohmeda S5</td>
			<td>GE Healthcare Finland Oy, Helsinki, Finland</td>
			<td>hemodynamic monitor</td>
			<td></td>
		</tr>
		<tr>
			<td>Engstr&#246;m Carestation</td>
			<td>GE Heathcare, Madison USA</td>
			<td>ventilator</td>
			<td></td>
		</tr>
		<tr>
			<td>Fentanyl-Janssen 0.05 mg/mL</td>
			<td>Janssen-Cilag GmbH, Neuss</td>
			<td>fentanyl</td>
			<td></td>
		</tr>
		<tr>
			<td>F&#252;hrungsstab, Durchmesser 4.3</td>
			<td>R&#252;sch</td>
			<td>endotracheal tube introducer</td>
			<td></td>
		</tr>
		<tr>
			<td>Incetomat-line 150 cm</td>
			<td>Fresenius, Kabi Deutschland, GmbH</td>
			<td>perfusor line</td>
			<td></td>
		</tr>
		<tr>
			<td>Intrafix Primeline</td>
			<td>B. Braun Melsungen AG, Melsungen, Germany</td>
			<td>Infusion line</td>
			<td></td>
		</tr>
		<tr>
			<td>Introducer sheath 5 Fr.</td>
			<td>Terumo Healthcare</td>
			<td>arterial introducer&#160;</td>
			<td></td>
		</tr>
		<tr>
			<td>INVOS</td>
			<td>Medtronic, Dublin, Ireland</td>
			<td>near infrared spectrometry</td>
			<td></td>
		</tr>
		<tr>
			<td>JOZA Einmal Nitril Untersuchungshandschuhe&#160;</td>
			<td>JOZA, M&#252;nchen, Germany</td>
			<td>disposable gloves</td>
			<td></td>
		</tr>
		<tr>
			<td>Laryngoscope, 45.48.50, KL 2000</td>
			<td>Medicon</td>
			<td>Laryngoscope handle</td>
			<td></td>
		</tr>
		<tr>
			<td>Littmann Classic III Stethoscope</td>
			<td>3M Deutschland GmbH, Neuss, Germany</td>
			<td>stethoscope</td>
			<td></td>
		</tr>
		<tr>
			<td>LPS (E. coli; Serotype O111:B4)</td>
			<td>Sigma-Aldrich, Switzerland</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>MAC Two-Lumen Central venous access set</td>
			<td>Arrow international inc. Reading, PA, USA</td>
			<td>venous introducer</td>
			<td></td>
		</tr>
		<tr>
			<td>Maimed Vlieskompresse</td>
			<td>Maimed GmbH, Neuenkirchen, Germany</td>
			<td>Fleece compress to fix the tongue</td>
			<td></td>
		</tr>
		<tr>
			<td>Masimo LNCS Adtx SpO2 sensor</td>
			<td>Masimo Corporation Irvine, Ca 92618 USA</td>
			<td>saturation clip for the tail</td>
			<td></td>
		</tr>
		<tr>
			<td>Masimo LNCS TC-I SpO2 ear clip sensor</td>
			<td>Masimo Corporation Irvine, Ca 92618 USA</td>
			<td>Saturation clip for the ear</td>
			<td></td>
		</tr>
		<tr>
			<td>Masimo Radical 7</td>
			<td>Masimo Corporation Irvine, Ca 92618 USA</td>
			<td>periphereal oxygen saturation&#160;&#160;&#160;</td>
			<td></td>
		</tr>
		<tr>
			<td>Midazolam 15 mg/3 mL</td>
			<td>B.Braun Melsungen AG, Germany</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Midmark Canine Mask Small Plastic with Diaphragm FRSCM-0005</td>
			<td>Midmark Corp., Dayton, Ohio, USA</td>
			<td>dog ventilation mask</td>
			<td></td>
		</tr>
		<tr>
			<td>Monocryl surgical suture</td>
			<td>Johnson &#38; Johnson, Belgium</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td>B.Braun Melsungen AG, Germany</td>
			<td>saline solution</td>
			<td></td>
		</tr>
		<tr>
			<td>NaCl 0.9 %</td>
			<td>Sanofi- Aventis, Seutschland GmbH</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Octeniderm farblos</td>
			<td>Sch&#252;lke &#38; Mayr GmbH, Nordenstedt, Germany</td>
			<td>Alcoholic disinfectant</td>
			<td></td>
		</tr>
		<tr>
			<td>Original Perfusor syringe 50 mL</td>
			<td>B.Braun Melsungen AG, Germany</td>
			<td>perfusor syringe</td>
			<td></td>
		</tr>
		<tr>
			<td>PA-Katheter Swan Ganz 7.5 Fr 110 cm</td>
			<td>Edwards Lifesciences LLC, Irvine CA, USA</td>
			<td>Swan-Ganz catheter</td>
			<td></td>
		</tr>
		<tr>
			<td>Perfusor FM Braun</td>
			<td>B.Braun Melsungen AG, Germany</td>
			<td>syringe pump</td>
			<td></td>
		</tr>
		<tr>
			<td>PiCCO catheter</td>
			<td>PULSION Medical Systems SE, Feldkirchen, DE</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Potassium chloride 1 M</td>
			<td>Fresenius, Kabi Germany GmbH</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Propofol 2% 20 mg/mL (50 mL flasks)</td>
			<td>Fresenius, Kabi Deutschland, GmbH</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Pulse-contour continous cardiac output System PiCCO2</td>
			<td>PULSION Medical Systems SE, Feldkirchen, DE</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>R&#252;schelit Super Safety Clear &#62;ID 6/6.5 /7.0 mm</td>
			<td>Teleflex Medical Sdn. Bhd, Malaysia</td>
			<td>endotracheal tube</td>
			<td></td>
		</tr>
		<tr>
			<td>Sonosite Micromaxx Ultrasoundsystem</td>
			<td>Sonosite Bothell, WA, USA&#160;</td>
			<td>ultrasound&#160;</td>
			<td></td>
		</tr>
		<tr>
			<td>Stainless Macintosh Gr&#246;&#223;e 4</td>
			<td>Welch Allyn69604</td>
			<td>blade for laryngoscope</td>
			<td></td>
		</tr>
		<tr>
			<td>Sterofundin</td>
			<td>B.Braun Melsungen AG, Melsungen, Germany</td>
			<td>Balanced electrolyte solution</td>
			<td></td>
		</tr>
		<tr>
			<td>Vasco OP sensitive&#160;</td>
			<td>B.Braun Melsungen AG, Germany</td>
			<td>sterile gloves</td>
			<td></td>
		</tr>
		<tr>
			<td>Vasofix Safety 22 G-16 G</td>
			<td>B.Braun Melsungen AG, Germany</td>
			<td>venous catheter</td>
			<td></td>
		</tr>
		<tr>
			<td>VBM Cuff Manometer</td>
			<td>VBM Medizintechnik GmbH, Sulz a.N., Germany&#160;</td>
			<td>cuff pressure gauge</td>
			<td></td>
		</tr>
	</tbody>
</table>

lipopolysaccharide infusion as a porcine endotoxemic shock model

Sepsis and septic shock are frequently encountered in patients treated in intensive care units (ICUs) and are among the leading causes of death in these patients. It is caused by a dysregulated immune response to an infection. Even with optimized treatment, mortality rates remain high, which makes further insights into the pathophysiology and new treatment options necessary. Lipopolysaccharide (LPS) is a component of the cell membrane of gram-negative bacteria, which are often responsible for infections causing sepsis and septic shock. 
The severity and high mortality of sepsis and septic shock make standardized experimental studies in humans impossible. Thus, an animal model is needed for further studies. The pig is especially well suited for this purpose as it closely resembles humans in anatomy, physiology, and size. 
This protocol provides an experimental model for endotoxemic shock in pigs by LPS infusion. We were able to reliably induce changes frequently observed in septic shock patients, including hemodynamic instability, respiratory failure, and acidosis. This will allow researchers to gain valuable insight into this highly relevant condition and evaluate new therapeutic approaches in an experimental setting.

For this study, six healthy male pigs aged 2-3 months and weighing 30-35 kg were anesthetized and received an infusion of lipopolysaccharide (LPS) to induce endotoxemia. To determine the appropriate dosage of LPS required to consistently induce symptoms of shock, the pigs were administered various induction doses of LPS ranging from 100 &#181;g kg-1 to 200 &#181;g kg-1 over a 30-min period, followed by a maintenance dose of 1/10 of the initial dose per hour for the remainder of the experiment. All a...

Watch this Scientific Journal Video about Lipopolysaccharide Infusion as a Porcine Endotoxemic Shock Model at JoVE.com

Author Spotlight: Induction of Experimental Endotoxemic Shock in Pigs for Studying Hemodynamic and Respiratory Failure

We provide a protocol for an experimental endotoxemic shock model in pigs by infusion of lipopolysaccharide.

Lipopolysaccharide Infusion as a Porcine Endotoxemic Shock Model

Sepsis and septic shock are frequently encountered in patients treated in intensive care units (ICUs) and are among the leading causes of death in these ...

With this protocol, we induce experimental endotoxemic shock in pigs. We were able to reliably cause symptoms of endotoxemia, such as hemodynamic instability and respiratory failure. Lipopolysaccharide is a toxic substance.When working with lipopolysaccharide, it is essential always to wear gloves, protective goggles, a mask, and a lab coat. This protocol provides an easy and reliable way to induce endotoxemia. Because of their similar anatomy and physiology, pigs are particularly well-suited for this kind of research as standard medical equipment may be used.Using this protocol, we will be able to study the effects of different ventilation strategies in respiratory failure and lung damage during endotoxemic shock.

lipopolysaccharide-infusion-as-a-porcine-endotoxemic-shock-model

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JoVE Journal

Medicine

767 Views.  University Medical Center of the Johannes Gutenberg-University. With this protocol, we induce experimental endotoxemic shock in pigs. We were able to reliably cause symptoms of endotoxemia, such as hemodynamic instability and respiratory failure. Lipopolysaccharide is a toxic substance.When working with lipopolysaccharide, it is essential always to wear gloves, protective goggles, a mask, and a lab coat. This protocol provides an easy and reliable way to induce endotoxemia. Because of their similar anatomy and physiology, pigs are particularly well...

Video: Author Spotlight: Induction of Experimental Endotoxemic Shock in Pigs for Studying Hemodynamic and Respiratory Failure

Fixed Volume or Fixed Pressure: A Murine Model of Hemorrhagic Shock

It is common knowledge that severe blood loss and traumatic injury can lead to a cascade of detrimental signaling events often resulting in mortality. 1, 2, 3, 4, 5 These signaling events can also lead to sepsis and/or multiple organ dysfunction (MOD). 6, 7, 8, 9 It is critical then to investigate the causes of suppressed immune function and detrimental signaling cascades in order to develop more effective ways to help patients who suffer from traumatic injuries. 10 This fixed pressure Hemorrhagic Shock (HS) procedure, although technically challenging, is an excellent resource for investigation of these pathophysiologic conditions. 11, 12, 13 Advances in the assessment of biological systems, i.e. Systems Biology have enabled the scientific community to further understand complex physiologic networks and cellular communication patterns. 14 Hemorrhagic Shock has proven to be a vital tool for unveiling these cellular communication patterns as they relate to immune function. 15, 16, 17, 18 This procedure can be mastered! This procedure can also be used as either a fixed volume or fixed pressure approach. We adapted this technique in the murine model to enhance research in innate and adaptive immune function. 19, 20, 21 Due to their small size HS in mice presents unique challenges. However due to the many available mouse strains, this species represents an unparalleled resource for the study of the biologic responses. The HS model is an important model for studying cellular communication patterns and the responses of systems such as hormonal and inflammatory mediator systems, and danger signals, i.e. DAMP and PAMP upregulation as it elicits distinct responses that differ from other forms of shock. 22, 23, 24, 25 The development of transgenic murine strains and the induction of biologic agents to inhibit specific signaling have presented valuable opportunities to further elucidate our understanding of the up and down regulation of signal transduction after severe blood loss, i.e. HS and trauma 26, 27, 28, 29, 30. 
There are numerous resuscitation methods (R) in association with HS and trauma. 31, 32, 33, 34 A fixed volume resuscitation method of solely lactated ringer solution (LR), equal to three times the shed blood volume, is used in this model to study endogenous mechanisms such as remote organ injury and systemic inflammation. 35, 36, 38 This method of resuscitation is proven to be effective in evaluating the effects of HS and trauma 38, 39.

The Hemorrhagic Shock model has been a reliable and reproducible resource facilitating the identification and understanding of signaling cascades associated with inflammation and end-organ damage after trauma. This article provides a step-by-step description of surgical and mechanical aspects associated with the Hemorrhagic Shock experimental procedure in mice.

It is common knowledge that severe blood loss and traumatic injury can lead to a cascade of detrimental signaling events often resulting in mortality. 1, ...

A Model of Chronic Nutrient Infusion in the Rat

Chronic exposure to excessive levels of nutrients is postulated to affect the function of several organs and tissues and to contribute to the development of the many complications associated with obesity and the metabolic syndrome, including type 2 diabetes. To study the mechanisms by which excessive levels of glucose and fatty acids affect the pancreatic beta-cell and the secretion of insulin, we have established a chronic nutrient infusion model in the rat. The procedure consists of catheterizing the right jugular vein and left carotid artery under general anesthesia; allowing a 7-day recuperation period; connecting the catheters to the pumps using a swivel and counterweight system that enables the animal to move freely in the cage; and infusing glucose and/or Intralipid (a soybean oil emulsion which generates a mixture of approximately 80% unsaturated/20% saturated fatty acids when infused with heparin) for 72 hr. This model offers several advantages, including the possibility to finely modulate the target levels of circulating glucose and fatty acids; the option to co-infuse pharmacological compounds; and the relatively short time frame as opposed to dietary models. It can be used to examine the mechanisms of nutrient-induced dysfunction in a variety of organs and to test the effectiveness of drugs in this context.

A protocol for chronic infusions of glucose and Intralipid in rats is described. This model can be used to study the impact of nutrient excess on organ function and physiological parameters.

Chronic exposure to excessive levels of nutrients is postulated to  affect the function of several organs and tissues and to contribute to the  ...

Heterotopic Renal Autotransplantation in a Porcine Model: A Step-by-Step Protocol

Kidney transplantation is the treatment of choice for patients suffering from end-stage renal disease. It offers better life expectancy and higher quality of life when compared to dialysis. Although the last few decades have seen major improvements in patient outcomes following kidney transplantation, the increasing shortage of available organs represents a severe problem worldwide. To expand the donor pool, marginal kidney grafts recovered from extended criteria donors (ECD) or donated after circulatory death (DCD) are now accepted for transplantation. To further improve the postoperative outcome of these marginal grafts, research must focus on new therapeutic approaches such as alternative preservation techniques, immunomodulation, gene transfer, and stem cell administration.
Experimental studies in animal models are the final step before newly developed techniques can be translated into clinical practice. Porcine kidney transplantation is an excellent model of human transplantation and allows investigation of novel approaches. The major advantage of the porcine model is its anatomical and physiological similarity to the human body, which facilitates the rapid translation of new findings to clinical trials. This article offers a surgical step-by-step protocol for an autotransplantation model and highlights key factors to ensure experimental success. Adequate pre- and postoperative housing, attentive anesthesia, and consistent surgical techniques result in favorable postoperative outcomes. Resection of the contralateral native kidney provides the opportunity to assess post-transplant graft function. The placement of venous and urinary catheters and the use of metabolic cages allow further detailed evaluation. For long-term follow-up studies and investigation of alternative graft preservation techniques, autotransplantation models are superior to allotransplantation models, as they avoid the confounding bias posed by rejection and immunosuppressive medication.

Porcine models of organ transplantation provide an important platform to study mechanisms of organ preservation. This article describes a heterotopic porcine renal autotransplantation model, which allows investigating new approaches to improve the outcome of transplantation using marginal kidney grafts.

Kidney transplantation is the treatment of choice for patients suffering from end-stage renal disease. It offers better life expectancy and higher quality ...

Porcine As a Training Module for Head and Neck Microvascular Reconstruction

Live models that resemble surgical conditions of humans are needed for training free-flap harvesting and anastomosis. Animal models for training purposes have been available for years in many surgical fields. We used the female (because they are easy to handle for the procedure) Yorkshire pigs for the head and neck reconstruction by harvesting the deep inferior epigastric artery perforator or the superior epigastric artery perforator flap. The anastomosis site (neck skin defect or tracheal wall defect) was prepared via the dissection of the common carotid artery and the internal jugular vein, in which 3.5&#215; loupe magnification was used for anastomosis as we use on human cases in real life. This procedure demonstrates a new training method using a reliable learning model and provides a detailed anatomy in a live scenario. We focused on the ischemia time, harvesting, vessel anastomosis, and designing the flap to fit the defect site. This model improves tissue handling and with the use of proper instruments can be repeated many times so that the surgeon is fully confident before starting the surgery on humans.

Here we present a protocol for the use of the pig superior epigastric artery perforator flap as a learning module for head and neck microvascular reconstruction.

Live models that resemble surgical conditions of humans are needed for training free-flap harvesting and anastomosis. Animal models for training purposes ...

A Pre-Clinical Porcine Model of Orthotopic Heart Transplantation

Fifty-years following the first successful report, cardiac transplantation remains the gold-standard treatment for eligible patients with advanced heart failure. Multiple small-animal models of heart transplantation have been used to study the acute and long-term effects of novel therapies. However, few are tested and demonstrated success in clinical trials. It is of critical importance to evaluate new therapies in a clinically relevant large-animal model for efficient and reliable translation of basic studies&#39;&#160;findings. Here, we describe a pre-clinical large-animal (porcine) model of orthotopic heart transplantation that has been firmly established and previously used to investigate novel cardioprotective strategies. This procedure focuses on acute ischemia-reperfusion injury and is a reliable method to investigate novel interventions which have been tested and validated in smaller experimental models, such as the murine model. We demonstrate its usefulness in assessing cardiac performance during the early post-transplantation period and other potential possibilities enabled by the model.

Here, we describe a pre-clinical large-animal (porcine) model of orthotopic heart transplantation that has been firmly established and utilized to investigate novel cardioprotective strategies.

Fifty-years following the first successful report, cardiac transplantation remains the gold-standard treatment for eligible patients with advanced heart ...

A Porcine Corneal Endothelial Organ Culture Model Using Split Corneal Buttons

Experimental research on corneal endothelial cells is associated with several difficulties. Human donor corneas are scarce and rarely available for experimental investigations as they are normally needed for transplantation. Endothelial cell cultures often do not translate well to in vivo situations. Due to the biostructural characteristics of non-human corneas, stromal swelling during cultivation induces substantial corneal endothelial cell loss, which makes it difficult to perform cultivation for an extended period of time. Deswelling agents such as dextran are used to counteract this response. However, they also cause significant endothelial cell loss. Therefore, an ex vivo organ culture model not requiring deswelling agents was established. Pig eyes from a local slaughterhouse were used to prepare split corneal buttons. After partial corneal trephination, the outer layers of the cornea (epithelium, bowman layer, parts of the stroma) were removed. This significantly reduces corneal endothelial cell loss induced by massive stromal swelling and Descemet&#39;s membrane folding throughout longer cultivation periods and improves general preservation of the endothelial cell layer. Subsequent complete corneal trephination was followed by the removal of the split corneal button from the remaining eye bulb and cultivation. Endothelial cell density was assessed at follow-up times of up to 15 days after preparation (i.e., days 1, 8, 15) using light microscopy. The preparation technique used allows a better preservation of the endothelial cell layer enabled by less stromal tissue swelling, which results in slow and linear decline rates in split corneal buttons comparable to human donor corneas. As this standardized organo-typically cultivated research model for the first time allows a stable cultivation for at least two weeks, it is a valuable alternative to human donor corneas for future investigations of various external factors with regards to their effects on the corneal endothelium.

Here, a step-by-step protocol for the preparation and cultivation of porcine split corneal buttons is presented. As this organo-typically cultivated organ culture model shows cell death rates within 15 days, comparable to human donor corneas, it represents the first model allowing long-term cultivation of non-human corneas without adding toxic dextran.

Experimental research on corneal endothelial cells is associated with several difficulties. Human donor corneas are scarce and rarely available for ...

A Mouse Model for Chronic Pancreatitis via Bile Duct TNBS Infusion

Chronic pancreatitis (CP) is a complex disease involving pancreatic inflammation and fibrosis, glandular atrophy, abdominal pain and other symptoms. Several rodent models have been developed to study CP, of which the bile duct 2,4,6 -trinitrobenzene sulfonic acid (TNBS) infusion model replicates the features of neuropathic pain seen in CP. However, bile duct drug infusion in mice is technically challenging. This protocol demonstrates the procedure of bile duct TNBS infusion for generation of a CP mouse model. TNBS was infused into the pancreas through the ampulla of Vater in the duodenum. This protocol optimized drug volume, surgical techniques, and drug handling during the procedure. TNBS-treated mice showed features of CP as reflected by bodyweight and pancreas weight reductions, changes in pain-associated behaviors, and abnormal pancreatic morphology. With these improvements, mortality associated with TNBS injection was minimal. This procedure is not only critical in generating pancreatic disease models but is also useful in local pancreatic drug delivery.

Chronic pancreatitis (CP) is a disease characterized by inflammation and fibrosis of the pancreas, often associated with intractable abdominal pain. This article focuses on refining the technique to generate a mouse model of CP via bile duct infusion with 2,4,6 -trinitrobenzene sulfonic acid (TNBS).

Chronic pancreatitis (CP) is a complex disease involving pancreatic inflammation and fibrosis, glandular atrophy, abdominal pain and other symptoms. ...

Establishment and Evaluation of a Porcine Vein Graft Disease Model

Venous graft disease (VGD) is the leading cause of coronary artery bypass graft (CABG) failure. Large animal models of CABG-VGD are needed for the investigation of disease mechanisms and the development of therapeutic strategies. 
To perform the surgery, we enter the cardiac chamber through the third intercostal space and carefully dissect the internal mammary vein and immerse it in normal saline. The right main coronary artery is then treated for ischemia. The target vessel is incised, a shunt plug is placed, and the distal end of the graft vein is anastomosed. The ascending aorta is partially blocked, and the proximal end of the graft vein is anastomosed after perforation. The graft vein is checked for patency, and the proximal right coronary artery is ligated. 
CABG surgery is performed in minipigs to harvest the left internal mammary vein for its use as a vascular graft. Serum biochemical tests are used to evaluate the physiological status of the animals after surgery. Ultrasound examination shows that the proximal, middle, and distal end of the graft vessel are unobstructed. In the surgical model, turbulent blood flow in the graft is observed upon histological examination after the CABG surgery, and venous graft stenosis associated with intimal hyperplasia is observed in the graft. The study here provides detailed surgical procedures for the establishment of a repeatable CABG-induced VGD model.

In this protocol, novel pig vein bypass grafting was performed through a small incision in the left chest wall without cardiopulmonary bypass. A postoperative pathology study was done, which showed intimal thickening.

Venous graft disease (VGD) is the leading cause of coronary artery bypass graft (CABG) failure. Large animal models of CABG-VGD are needed for the ...

Porcine Liver Transplantation Without Veno-Venous Bypass As an Extended Criteria Donor Model

Liver transplantation is regarded as the gold standard for the treatment of a variety of fatal hepatic diseases. However, unsolved issues of chronic graft failure, ongoing organ donor shortages, and the increased use of marginal grafts call for the improvement of current concepts, such as the implementation of organ machine perfusion. In order to evaluate new methods of graft reconditioning and modulation, translational models are required. With respect to anatomical and physiological similarities to humans and recent progress in the field of xenotransplantation, pigs have become the main large animal species used in transplantation models. After the initial introduction of a porcine orthotopic liver transplant model by Garnier et al. in 1965, several modifications have been published over the past 60 years.
Due to specifies-specific anatomical traits, a veno-venous bypass during the anhepatic phase is regarded as a necessity to reduce intestinal congestion and ischemia resulting in hemodynamic instability and perioperative mortality. However, the implementation of a bypass increases the technical and logistical complexity of the procedure. Furthermore, associated complications such as air embolism, hemorrhage, and the need for a simultaneous splenectomy have been reported previously.
In this protocol, we describe a model of porcine orthotopic liver transplantation without the use of a veno-venous bypass. The engraftment of donor livers after static cold storage of 20 h - simulating extended criteria donor conditions - demonstrates that this simplified approach can be performed without significant hemodynamic alterations or intraoperative mortality and with regular uptake of liver function (as defined by bile production and liver-specific CYP1A2 metabolism). The success of this approach is ensured by an optimized surgical technique and a sophisticated anesthesiologic volume and vasopressor management.
This model should be of special interest for workgroups focusing on the immediate postoperative course, ischemia-reperfusion injury, associated immunological mechanisms, and the reconditioning of extended criteria donor organs.

In this protocol, a model of porcine orthotopic liver transplantation after static cold storage of donor organs for 20 h without the use of a veno-venous bypass during engraftment is described. The approach uses a simplified surgical technique with minimization of the anhepatic phase and sophisticated volume and vasopressor management.

Liver transplantation is regarded as the gold standard for the treatment of a variety of fatal hepatic diseases. However, unsolved issues of chronic graft ...

Delivery of Cardioactive Therapeutics in a Porcine Myocardial Infarction Model

Myocardial infarction is one of the leading causes of death and disability worldwide, and there is an urgent need for novel cardioprotective or regenerative strategies. An essential component of drug development is determining how a novel therapeutic is to be administered. Physiologically relevant large animal models are of critical importance in assessing the feasibility and efficacy of various therapeutic delivery strategies. Due to their similarities to humans in cardiovascular physiology, coronary vascular anatomy, and heart weight to body weight ratio, swine is one of the preferred species in the preclinical evaluation of new therapies for myocardial infarction. The present protocol describes three methods of administering cardioactive therapeutic agents in a porcine model. After percutaneously induced myocardial infarction, female landrace swine received treatment with novel agents through either: (1) thoracotomy and transepicardial injection, (2) catheter-based transendocardial injection, or (3) intravenous infusion via jugular vein osmotic minipump. The procedures employed for each technique are reproducible, resulting in reliable cardioactive drug delivery. These models can be easily adapted to suit individual study designs, and each of these delivery techniques can be used to investigate a variety of possible interventions. Therefore, these methods are a useful tool for translational scientists pursuing novel biological approaches in cardiac repair following myocardial infarction.

The present protocol describes three methods of administering cardioactive therapeutic agents in a porcine model. Female landrace swine received treatment through either: (1) thoracotomy and transepicardial injection, (2) catheter-based transendocardial injection, or (3) intravenous infusion via jugular vein osmotic minipump.