Tutte le procedure descritte sono condotte in conformità con gli Istituti Nazionali di Sanità le linee guida per la cura e l&#39;uso di animali nella ricerca e tutti i protocolli di animali sono stati approvati dalla Oregon Health &amp; Science Animal Care dell&#39;Università e del Comitato Istituzionale Usa. 1. Preparazione chirurgica <ol><li> Pesare il mouse. La procedura descritta viene eseguita su topi C57BL / 6 di peso compreso tra 20 e 25 g. L&#39;anestesia viene indotta in una scatola di induzione con isofluorano 3-4%, e poi mantenuto con 1,5-2,5% isoflurano in aria / ossigeno miscela. </li><li> Lubrificare gli occhi e la posizione supina animale su una piastra elettrica. Immobilizzare 4 estremità con del nastro. Le zampe posteriori può essere registrato in una posizione neutrale, invece, le zampe anteriori dovrebbero essere protetti il ​​più vicino alla parete toracica possibile per permettere una completa escursione della parete toracica durante le compressioni toraciche. </li><li> Lubrificare e posizionare una sonda rettale della temperatura. Temperatura è controllata tramite una piastra elettrica e lampada collegata ad un regolatore di temperatura elettronico (Digi-Sense, Cole Parmer, Vernon Hills IL), che è destinata a mantenere 37.0 ° C. Poiché è possibile che un gradiente di temperatura all&#39;interno l&#39;animale potrebbe sviluppare nel corso della no-flusso di Stato, è importante che la temperatura essere misurati e controllati presso l&#39;organo di interesse. </li><li> Intubare la trachea con un 22 cm 2.5 ga catetere in teflon (Insyte-W, BD, Franklin NJ) e la fine taglio distale di un introduttore angolata (Frova introduttore, Cook Medical, Bloomington IN). Altri metodi di intubazione tracheale sono accettabili, tuttavia, l&#39;uso del introduttore angolato permette il corretto posizionamento del collo in una posizione leggermente esteso, che ottimizza l&#39;esposizione chirurgica per il posizionamento del catetere endovenoso. Il mozzo catetere endotracheale è fissato con un anello di sutura al incisivo e mantenuto con leggera tensione per immobilizzare la testa durante le compressioni toraciche. </li><li> Ventilare meccanicamente il mouse con un ventilatore roditore insieme a 140 microlitri, 150 r / minuto. Questo non è corretto per il peso che questo protocollo è sempre eseguita in 20-25 g di animali. Non troppo approfondire l&#39;anestesia. Non impostare il ventilatore per applicare pressione espiratoria finale come questo danneggia la rianimazione. </li><li> Usando la tecnica sterile ed un microscopio operatorio, posto un pre-lavati PE-10 catetere nella vena giugulare. Entrambi i lati possono essere utilizzati, ma l&#39;utilizzo del lato più vicino all&#39;operatore riduce il rischio di dislocazione del catetere durante compressioni toraciche o altre manipolazioni. 0,5% bupivicaine, 0,1 ml è infitrated in lembi della ferita per il controllo del dolore postoperatorio. </li><li> Fissare il PE-10 catetere nella chiusura della cute con cianoacrilato adesivo chirurgico. </li><li> Luogo elettrodi ECG sottocutaneo e collegarsi al dispositivo di monitoraggio. Una grande attenzione al percorso del segnale e la massimizzazione del segnale stesso è fondamentale per il successo della rianimazione. Garantire che tutti i cavi siano fissati alla superficie operativa, ridurre al minimo segnale di incroci, e minimizzare isolanti (come l&#39;aria in aghi cavi o fili intrecciati) all&#39;interno del percorso del segnale. Aghi solido collegato al cavo nonstranded possono essere acquistati o fatti in laboratorio. Una volta collegato, di ottimizzare il segnale ECG sul monitor. </li></ol> 2. Arresto cardiaco <ol><li> Assicurarsi che il mouse è normotermico, definita come temperatura rettale 36,5 ° C - 37,5 ° C. Somministrare 40 ml di temperatura ambiente 0,5 M di cloruro di potassio per via endovenosa e osservare isoelettrico analisi su ECG. Aggiustamento della dose di peso non è necessario, entro la gamma di 20-25 g. Avvio timer arresto. </li><li> Staccare il respiratore. Interrompere il vapore anestetico. Spegnere la piastra elettrica e di qualsiasi altra attrezzatura che produce rumore elettronico che possono interferire con il monitoraggio ECG. Mettere una coperta isolante al posto del mouse. </li><li> Record di temperatura ogni minuto durante l&#39;arresto cardiaco. Se necessario, una lampada di riscaldamento può essere utilizzato per portare la temperatura interna fino alla gamma normotermico. Durante l&#39;arresto cardiaco, preparare forniture e attrezzature (ad esempio, la siringa di epinefrina) per la rianimazione. Una lista di controllo può essere utile per garantire la rianimazione ininterrotta, che è essenziale per la sopravvivenza. </li><li> Dopo 7 minuti, 30 secondi di arresto cardiaco, ricollegare il ventilatore e aumentare la velocità a 180 atti / min, mantenendo il volume corrente al pre-arresto impostazione. </li><li> A 8 minuti, iniziare le compressioni toraciche a 300 BPM. Artefatti da movimento sulla ECG può essere utilizzato per votare giudicare RCP. Compressioni toraciche devono essere consegnati con il dito indice, 5 mm sopra il processo xifoideo e leggermente a sinistra della linea mediana. Il torace deve essere compresso 1/3-1/2 della distanza antero-posteriore e rinculo completo deve essere consentito tra compressioni. Il posizionamento delle dita e la pressione di compressione ottimale sono assolutamente critiche. Mancato raggiungimento di sopravvivenza in questo modello è quasi sempre a causa della non ottimale RCP. </li><li> Infondere 0,5 ml di adrenalina, diluita a 15 mg / ml, nei primi 30 secondi di RCP. Dose di adrenalina totale è di 8-12 mg. Osservare attentamente le ECG per il ritorno della circolazione spontanea (ROSC). Complesso QRS stretto complessi sono visti tra gli artefatti di compressione. ROSC si verifica di solito tra 90 secondi e 2 minuti dopo l&#39;inizio RCP. Rianimazione è abbandonato ROSC se non si verifica da 3 minuti. Frequenti contrazioni ventricolari premature e cambiamenti ECG assi sono stati osservati nei primi 2 minuti dopo ROSC, e quasi sempre risolvere in tachicardia sinusale stabile a 2 minuti. </li><li> Registrare il tempo totale di rianimazione e la dose di adrenalina. Rileva temperatura ogni minuto per 10 minuti dopo ROSC. </li><li> Porta ECG può essere rimosso quando inizia la respirazione spontanea, di solito entro 12-15 minuti dopo il ROSC. </li><li> Estubare la trachea quando frequenza respiratoria spontanea è&gt; 60/min. </li><li> Posizionare il mouse in una gabbia di recupero su una superficie a temperatura controllata impostata a 37 ° C per le prime 2 postprocedure ore, assicurando un facile accesso al cibo e all&#39;acqua. La gabbia può poi essere spostato in serie condizioni abitative post-operatorio quando il mouse è completamente recuperato da anestesia ed è attivo. </li></ol> 3. Dissanguamento / perfusione-fissaggio e Harvest rene <ol><li> 24 ore dopo CA / CPR, indurre l&#39;anestesia con isoflurano 3-4% e sicuro l&#39;animale in posizione supina su una superficie chirurgico in una cappa aspirante che è appropriato per l&#39;uso con formalina .. </li><li> Approfondire l&#39;anestetico aumentando gradualmente la concentrazione di vapore anestetico al 5% e di garantire il mouse è profondamente anestetizzati come evidenziato dalla cessazione della respirazione spontanea. </li><li> Eseguire una toracotomia a conchiglia e exsanguinate il mouse tramite puntura apicale del ventricolo cardiaco sinistro secondo le tecniche standard. </li><li> Attraverso lo stesso ago, amministrare 0,9% soluzione salina per infusione lenta. Per acclerate perfusione / dissanguamento, nick l&#39;appendice atriale destra con le forbici. Eseguire una laparotomia e osservare i reni. Quando sono scottate, soluzione salina può essere cambiato in formalina 4% per il fissaggio. Reni sono poi inclusi in paraffina e colorati con Fluoro-Jade B per la quantificazione di necrosi tubolare epiteliali. </li></ol> 4. Rappresentante dei risultati: Quando CA è indotta, pressione arteriosa media (MAP) e regionali renale il flusso di sangue (RRBCF) caduta quasi a zero e rimanere stabile fino rianimazione ha inizio (Figura 1). 24 ore dopo CA / CPR, indici sierici di funzionalità renale (azotemia, azotemia e creatinina) sono significativamente elevati rispetto a sham-operati animali. AST / ALT sono elevati, offrendo la prova di profonda su tutto il corpo ischemia (Figura 2). Neutrofili-gelatinasi associati lipocalina (NGAL), un indicatore sensibile del danno ischemico renale è massicciamente dopo 24 ore upregulated CA / CPR (Figura 3). Infine, microfotografie dimostrare l&#39;irregolare, la necrosi ischemica midollare tipica di lesioni renali con assottigliamento dell&#39;epitelio tubolare e riempimento luminale su ematossilina ed eosina (Figura 4, pannello a) e la morte cellulare nel vasto midollare tubulare quando colorati con fluoro-giada B ( Figura 4, pannello b). <img src="/files/ftp_upload/3116/3116fig1.jpg" alt="Figura 1" /> Figura 1. Arresto cardiaco induce la perdita istantanea della pressione di perfusione, qui rappresentata come pressione arteriosa media (MAP) misurata a livello dell&#39;arteria femorale, provocando quasi completa cessazione del flusso ematico renale regionale corticale (RRCBF) per tutto il periodo di arresto cardiaco (ombreggiato area). Rianimazione con le compressioni toraciche e torna adrenalina MAPPA alla normalità e RRCBF aumenta costantemente nel periodo di rianimazione post. Ristampato con il permesso di 14. <img src="/files/ftp_upload/3116/3116fig2.jpg" alt="Figura 2" /> Figura 2. 24h postprocedure, azotemia (BUN), creatinina sierica, e l&#39;estensione della morte delle cellule tubulari sono significativamente elevati negli animali che sono stati sottoposti CA / CPR in confronto con gli animali trattati con una procedura simulata. CA / CPR induce una pan-organismal insulto ischemico, qui evidenziato dalla massiccia elevazione del fegato-funzione degli enzimi dell&#39;alanina aminotransferasi (ALT) e aspartato aminotransferasi (AST) in CA / CPR topi rispetto ai simulato animali trattati. <img src="/files/ftp_upload/3116/3116fig3.jpg" alt="Figura 3" /> Figura 3. Western blot eseguiti utilizzando anticorpi policlonali di neutrofili gelatinasi associati lipocalina (NGAL), un indicatore sensibile del danno ischemico renale. I campioni di urine sono stati ottenuti immediatamente prima (&quot;pre&quot;) e 24 ore dopo (&quot;24 ore&quot;) CA / CPR in 4 animali (con l&#39;etichetta a, b, c, d sopra). NGAL è massicciamente upregulated nel topourine dopo CA / RCP. Ristampato con il permesso di 14. <img src="/files/ftp_upload/3116/3116fig4.jpg" alt="Figura 4" /> Figura 4. A) ematossilina e eosina di un breve tratto ilare asse di 24 ore tessuto renale dopo CA / RCP. Vi è un danno a macchia di leopardo ma chiara tubuli midollare e corticomidollare con tubolari tamponamento. Le frecce indicano tubuli danneggiati con gonfiore, nuclei picnotici all&#39;incrocio corticomidollare. B) Flouro-giada B macchia della stessa regione nello stesso animale, 24 ore dopo CA / RCP. Fluoro-giada macchie B cellule necrotiche verde brillante, mostrando irregolare corticomidollare necrosi tubulare. Le frecce indicano vivacemente colorati tubuli danneggiati a livello della giunzione corticomidollare. Questi risultati sono sostanzialmente simili a biopsia renale da esseri umani che sviluppano AKI, ea differenza di quelle prodotte da altri modelli animali di danno renale acuto.

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Nessun conflitto di interessi dichiarati.

Il modello normotermico di arresto cardiaco e rianimazione cardiopolmonare nel topo offre molteplici vie di valutazione in un modello che riproduce la fisiopatologia e la morfologia della causa clinica più comune di AKI, tutto il corpo ipoperfusione. La verifica di ipotesi può essere aiutata da accesso a tutta una serie di tecniche di manipolazione genetica e l&#39;anatomia ben capito e caratterizzata e fisiologia del topo di laboratorio. Come descritto qui, la sopravvivenza in mani espert...

<table border="1"><tbody><tr><th> Nome del reagente </th><th> Azienda </th><th> Numero di catalogo </th></tr><tr><td> Cloruro di potassio </td><td> Abbott Medical </td><td> 06653-5 </td></tr><tr><td> Isoflurano </td><td> Abbott Medical </td><td> 05260-05 (e altri) </td></tr><tr><td> Epinefrina HCl </td><td> Multiplo </td><td> Multiplo </td></tr><tr><td> Digi-Sense Regolatore di temperatura </td><td> Cole-Palmer </td><td> EW-89000-00 </td></tr><tr><td> Angiocath IV Cath </td><td> VWR </td><td> 381134 </td></tr><tr><td> Frova introduttore vie ad angolo </td><td> Cucinare </td><td> G27282 </td></tr><tr><td> Ventilatore MicroVent per il Mice </td><td> Harvard Apparatus </td><td> 733591 </td></tr></tbody></table>

normothermic cardiac arrest and cardiopulmonary resuscitation: a mouse model of ischemia-reperfusion injury

Danno renale acuto (AKI) è un comune, altamente letale, complicazione di malattia critica che ha un alto tasso di mortalità 1-4 e che è più frequentemente causata da tutto il corpo ipoperfusione. 5,6 riproduzione di successo di tutto il corpo ipoperfusione in modelli di roditori è stato irto di difficoltà. 7-9,9,10 modelle che impiegano ischemia focale hanno ripetutamente dimostrato che i risultati non si traducono in ambito clinico, e in modelli animali più grandi che permettono di accedere a tutta la mancanza ipoperfusione corpo al set di strumenti completo di manipolazione genetica possibile nel topo. 11,12 Tuttavia, negli ultimi anni un modello murino di arresto cardiaco e rianimazione cardiopolmonare è emerso che possono essere adattati a modello AKI. 13 Questo modello riproduce affidabile fisiologico, risultati funzionali, anatomiche e istologiche visto in clinica AKI , si sta rapidamente ripetibile, e offre tutti i vantaggi di un modello murino chirurgico, compreso l&#39;accesso alle tecniche di manipolazione genetica, relativamente a basso costo per grandi animali, e facilità d&#39;uso. Il nostro gruppo ha sviluppato una vasta esperienza con l&#39;utilizzo di questo modello per valutare una serie di organo-specifici risultati di AKI. 14,15

Watch this Scientific Journal Video about Normothermic Cardiac Arrest and Cardiopulmonary Resuscitation: A Mouse Model of Ischemia-Reperfusion Injury at JoVE.com

Normothermic Cardiac Arrest and Cardiopulmonary Resuscitation: A Mouse Model of Ischemia-Reperfusion Injury

Un modello potente per perioperatoria e critica lesioni legate ai reni per acuti è presentato. Utilizzando tutto il corpo ipoperfusione indotta da arresto cardiaco è possibile replicare quasi alterazioni istologiche e funzionali del clinico AKI.

Normotermico arresto cardiaco e rianimazione cardiopolmonare: un modello murino di ischemia-riperfusione

Acute Kidney Injury (AKI) is a common, highly lethal, complication of critical illness which has a high mortality1-4 and which is most 
frequently caused ...

normothermic-cardiac-arrest-cardiopulmonary-resuscitation-mouse-model

Research

JoVE Journal

Medicine

17.9K Views.  Oregon Health & Sciences University. Un modello potente per perioperatoria e critica lesioni legate ai reni per acuti è presentato. Utilizzando tutto il corpo ipoperfusione indotta da arresto cardiaco è possibile replicare quasi alterazioni istologiche e funzionali del clinico AKI.

Video: Normothermic Cardiac Arrest and Cardiopulmonary Resuscitation: A Mouse Model of Ischemia-Reperfusion Injury

Ischemia-reperfusion Model of Acute Kidney Injury and Post Injury Fibrosis in Mice

Ischemia-reperfusion induced acute kidney injury (IR-AKI) is widely used as a model of AKI in mice, but results are often quite variable with high, often unreported mortality rates that may confound analyses. Bilateral renal pedicle clamping is commonly used to induce IR-AKI, but differences between effective clamp pressures and/or renal responses to ischemia between kidneys often lead to more variable results. In addition, shorter clamp times are known to induce more variable tubular injury, and while mice undergoing bilateral injury with longer clamp times develop more consistent tubular injury, they often die within the first 3 days after injury due to severe renal insufficiency. To improve post-injury survival and obtain more consistent and predictable results, we have developed two models of unilateral ischemia-reperfusion injury followed by contralateral nephrectomy. Both surgeries are performed using a dorsal approach, reducing surgical stress resulting from ventral laparotomy, commonly used for mouse IR-AKI surgeries. For induction of moderate injury BALB/c mice undergo unilateral clamping of the renal pedicle for 26 min and also undergo simultaneous contralateral nephrectomy. Using this approach, 50-60% of mice develop moderate AKI 24 hr after injury but 90-100% of mice survive. To induce more severe AKI, BALB/c mice undergo renal pedicle clamping for 30 min followed by contralateral nephrectomy 8 days after injury. This allows functional assessment of renal recovery after injury with 90-100% survival. Early post-injury tubular damage as well as post injury fibrosis are highly consistent using this model.

We describe models of moderate and severe ischemia-reperfusion-induced kidney injury in which the mice undergo unilateral renal pedicle clamping followed by simultaneous or delayed contralateral nephrectomy, respectively. These models consistently give rise to renal dysfunction and post-injury fibrosis, but injury severity and survival are dependent on mouse background, age and surgical equipment.

Ischemia-riperfusione Modello di danno renale acuta e post Infortunio fibrosi nei topi

Ischemia-reperfusion induced acute kidney injury (IR-AKI) is widely used as a model of AKI in mice, but results are often quite variable with high, often ...

Ricerca

Medicina

Induction and Assessment of Ischemia-reperfusion Injury in Langendorff-perfused Rat Hearts

The biochemical events surrounding ischemia reperfusion injury in the acute setting are of great importance to furthering novel treatment options for myocardial infarction and cardiac complications of thoracic surgery. The ability of certain drugs to precondition the myocardium against ischemia reperfusion injury has led to multiple clinical trials, with little success. The isolated heart model allows acute observation of the functional effects of ischemia reperfusion injury in real time, including the effects of various pharmacological interventions administered at any time-point before or within the ischemia-reperfusion injury window. Since brief periods of ischemia can precondition the heart against ischemic injury, in situ aortic cannulation is performed to allow for functional assessment of non-preconditioned myocardium. A saline filled balloon is placed into the left ventricle to allow for real-time measurement of pressure generation. Ischemic injury is simulated by the cessation of perfusion buffer flow, followed by reperfusion. The duration of both ischemia and reperfusion can be modulated to examine biochemical events at any given time-point. Although the Langendorff isolated heart model does not allow for the consideration of systemic events affecting ischemia and reperfusion, it is an excellent model for the examination of acute functional and biochemical events within the window of ischemia reperfusion injury as well as the effect of pharmacological intervention on cardiac pre- and postconditioning. The goal of this protocol is to demonstrate how to perform in situ aortic cannulation and heart excision followed by ischemia/reperfusion injury in the Langendorff model.

The isolated rat heart is an enduring model for ischemia reperfusion injury. Here, we describe the process of harvesting the beating heart from a rat via in situ aortic cannulation, Langendorff perfusion of the heart, simulated ischemia-reperfusion injury, and infarct staining to confirm the extent of ischemic insult.

Induzione e valutazione di ischemia-riperfusione Injury in Langendorff-perfusi Hearts Rat

The biochemical events surrounding ischemia reperfusion injury in the acute setting are of great importance to furthering novel treatment options for ...

Murine Model of Intestinal Ischemia-reperfusion Injury

Intestinal ischemia is a life-threatening condition associated with a broad range of clinical conditions including atherosclerosis, thrombosis, hypotension, necrotizing enterocolitis, bowel transplantation, trauma and chronic inflammation. Intestinal ischemia-reperfusion (IR) injury is a consequence of acute mesenteric ischemia, caused by inadequate blood flow through the mesenteric vessels, resulting in intestinal damage. Reperfusion following ischemia can further exacerbate damage of the intestine. The mechanisms of IR injury are complex and poorly understood. Therefore, experimental small animal models are critical for understanding the pathophysiology of IR injury and the development of novel therapies.
Here we describe a mouse model of acute intestinal IR injury that provides reproducible injury of the small intestine without mortality. This is achieved by inducing ischemia in the region of the distal ileum by temporally occluding the peripheral and terminal collateral branches of the superior mesenteric artery for 60 min using microvascular clips. Reperfusion for 1 hr, or 2 hr after injury results in reproducible injury of the intestine examined by histological analysis. Proper position of the microvascular clips is critical for the procedure. Therefore the video clip provides a detailed visual step-by-step description of this technique. This model of intestinal IR injury can be utilized to study the cellular and molecular mechanisms of injury and regeneration.

Here we describe the detailed procedure of intestinal ischemia-reperfusion in mice which results in reproducible injury without mortality to encourage the standardization of this technique across the field. This model of intestinal ischemia-reperfusion injury can be utilized to study the cellular and molecular mechanisms of injury and regeneration.

Modello murino di ischemia-riperfusione intestinale Injury

Intestinal ischemia is a life-threatening condition associated with a broad range of clinical conditions including atherosclerosis, thrombosis, ...

A Mouse Model of Retinal Ischemia-Reperfusion Injury Through Elevation of Intraocular Pressure

Retinal ischemia-reperfusion (I/R) is a pathophysiological process contributing to cellular damage in multiple ocular conditions, including glaucoma, diabetic retinopathy, and retinal vascular occlusions. Rodent models of I/R injury are providing significant insights into mechanisms and treatment strategies for human I/R injury, especially with regard to neurodegenerative damage in the retinal neurovascular unit. Presented here is a protocol for inducing retinal I/R injury in mice through elevation of intraocular pressure (IOP). In this protocol, the ocular anterior chamber is cannulated with a needle, through which flows the drip of an elevated saline reservoir. Using this drip to raise IOP above systolic arterial blood pressure, a practitioner temporarily halts inner retinal blood flow (ischemia). When circulation is reinstated (reperfusion) by removal of the cannula, severe cellular damage ensues, resulting ultimately in retinal neurodegeneration. Recent studies demonstrate inflammation, vascular permeability, and capillary degeneration as additional elements of this model. Compared to alternative retinal I/R methodologies, such as retinal arterial ligation, retinal I/R injury by elevated IOP offers advantages in its&#160;anatomical specificity, experimental tractability, and technical accessibility, presenting itself as a valuable tool for examining neuronal pathogenesis and therapy in the retinal neurovascular unit.

This article describes a procedure for inducing retinal ischemia-reperfusion injury by elevated intraocular pressure in mice. Retinal ischemia-reperfusion injury by elevated intraocular pressure serves to model human pathologies characterized by compromised oxygen and nutrient delivery in the retina, enabling researchers to examine potential cellular mechanisms and treatments for human diseases of the retinal neurovascular unit.

Un modello murino di retina ischemia-riperfusione lesioni a causa di aumento della pressione intraoculare

Retinal ischemia-reperfusion (I/R) is a pathophysiological process contributing to cellular damage in multiple ocular conditions, including glaucoma, ...

Ultrasonographic Assessment During Cardiopulmonary Resuscitation

The US-CAB (Ultrasound, Circulation/Airway/Breathing) protocol integrates several sonographic techniques into a structured assessment of the circulation, airway, and breathing status of a patient during cardiopulmonary resuscitation (CPR) in an advanced life support-compliant manner. US-C provides a subxiphoid view of the heart, to look for potentially reversible causes of disease, such as pericardial effusion, pulmonary embolism, hypovolemia, and acute coronary thrombosis. Sonographic cardiac activity during CPR not only helps differentiate pseudo-pulseless electrical activity (PEA) from true PEA but also represents a higher chance of the return of spontaneous circulation (ROSC) and survival. Evaluation of the inferior vena cava (IVC) shows the fluid status of the patient and indicates the best methods to use for fluid resuscitation. If aortic dissection is suspected, a subxiphoid view of the aorta is suggested for identifying an intimal flap. Once intubation is done, tracheal ultrasound (US-A) at the suprasternal notch helps differentiate endotracheal intubation (one air-mucosal interface with one comet-tail) from esophageal intubation (double tract sign). Immediately following US-A, bilateral lung US (US-B) should be done to confirm proper bilateral ventilation using the lung sliding sign. In addition, US-C can be serially followed to see the dynamic changes in the cardiac chambers and IVC, or any cardiac contraction suggestive of ROSC. US-B can also detect coexisting lung or pleural pathologies without interfering with the performance of CPR. The main concern when implementing this method is maintaining high-quality CPR without delays in chest compressions when performing US-CAB. Rigorous training and continued practice are key to minimize any interruptions during resuscitation.

Here, we present a US-CAB (Ultrasound, Circulation/Airway/Breathing) protocol for use during cardiopulmonary resuscitation (CPR). US-C evaluates the subxiphoid view of the heart and inferior vena cava. After intubation, tracheal US (US-A) and lung US (US-B) help confirm endotracheal intubation and proper ventilation.

Valutazione ultrasonografica durante la rianimazione cardiopolmonare

The US-CAB (Ultrasound, Circulation/Airway/Breathing) protocol integrates several sonographic techniques into a structured assessment of the circulation, ...

A Pre-clinical Rat Model for the Study of Ischemia-reperfusion Injury in Reconstructive Microsurgery

Ischemia-reperfusion injury is the main cause of flap failure in reconstructive microsurgery. The rat is the preferred preclinical animal model in many areas of biomedical research due to its cost-effectiveness and its translation to humans. This protocol describes a method to create a preclinical free skin flap model in rats with ischemia-reperfusion injury. The described 3 cm x 6 cm rat free skin flap model is easily obtained after the placement of several vascular ligatures and the section of the vascular pedicle. Then, 8 h after the ischemic insult and completion of the microsurgical anastomosis, the free skin flap develops the tissue damage. These ischemia-reperfusion injury-related damages can be studied in this model, making it a suitable model for evaluating therapeutic agents to address this pathophysiological process. Furthermore, two main monitoring techniques are described in the protocol for the assessment of this animal model: transit-time ultrasound technology and laser speckle contrast analysis.

Here, we describe a pre-clinical animal model for studying the pathophysiology of ischemia-reperfusion injury in reconstructive microsurgery. This free skin flap model based on the superficial caudal epigastric vessels in the rat may also allow for the evaluation of different therapies and compounds to counteract ischemia-reperfusion injury-related damage.

Un modello di ratto preclinico per lo studio delle lesioni ischemia-reperfusione in microchirurgia ricostruttiva

Ischemia-reperfusion injury is the main cause of flap failure in reconstructive microsurgery. The rat is the preferred preclinical animal model in many ...

Delayed Intramyocardial Delivery of Stem Cells after Ischemia Reperfusion Injury in a Murine Model

There is significant interest in the use of stem cells (SCs) for the recovery of cardiac function in individuals with myocardial injuries. Most commonly, cardiac stem cell therapy is studied by delivering SCs concurrently with the induction of myocardial injury. However, this approach presents two significant limitations: the early hostile pro-inflammatory ischemic environment may affect the survival of transplanted SCs, and it does not represent the subacute infarction scenario where SCs will likely be used. Here we describe a two-part series of surgical procedures for the induction of ischemia-reperfusion injury and delivery of mesenchymal stem cells (MSCs). This method of stem cell administration may allow for the longer viability and retention around damaged tissue by circumventing the initial immune response. A model of ischemia reperfusion injury was induced in mice accompanied by the delivery of mesenchymal stem cells (3.0 x 105), stably expressing the reporter gene firefly luciferase under the constitutively expressed CMV promoter, intramyocardially 7 days later. The animals were imaged via ultrasound and bioluminescent imaging for confirmation of injury and injection of cells, respectively. Importantly, there was no added complication rate when performing this two-procedure approach for SC delivery. This method of stem cell administration, collectively with the utilization of state-of-the-art reporter genes, may allow for the in vivo study of viability and retention of transplanted SCs in a situation of chronic ischemia commonly seen clinically, while also circumventing the initial pro-inflammatory response. In summary, we established a protocol for the delayed delivery of stem cells into the myocardium, which can be used as a potential new approach in promoting regeneration of the damaged tissue.

Stems cells are continuously investigated as potential treatments for individuals with myocardial damage, however, their decreased viability and retention within injured tissue can impact their long-term efficacy. In this manuscript we describe an alternative method for stem cell delivery in a murine model of ischemia reperfusion injury.

Consegna intramiocardica ritardata di cellule staminali dopo l'infortunio di ricottamento ischemia in un modello Murine

There is significant interest in the use of stem cells (SCs) for the recovery of cardiac function in individuals with myocardial injuries. Most commonly, ...

A Rat Lung Transplantation Model of Warm Ischemia/Reperfusion Injury: Optimizations to Improve Outcomes

From our experience with rat lung transplantation, we have found several areas for improvement. Information in the existing literature regarding methods for choosing appropriate cuff sizes for the pulmonary vein (PV), pulmonary artery (PA), or bronchus (Br) are varied, thus making the determination of proper cuff size during rat lung transplantation an exercise of trial and error. By standardizing the cuffing technique to use the smallest effective cuff appropriate for the size of the vessel or bronchus, one can make the transplantation procedure safer, faster, and more successful. Since diameters of the PV, PA, and Br are related to the body weight of the rat, we present a strategy to choosing an appropriate size using a weight-based guide. Since lung volume is also related to body weight, we recommend that this relationship should also be considered when choosing the proper volume of air for donor lung inflation during warm ischemia as well as for the proper volume of PBS to be instilled during bronchoalveolar lavage (BAL) fluid collection. We also describe methods for 4th intercostal space dissection, wound closure, and sample collection from both the native and transplanted lobes.

Here, we present optimizations to a rat lung transplantation model that serve to improve outcomes. We provide a size guide for cuffs based on body weight, a measurement strategy to ascertain the 4th intercostal space, and methods of wound closure and BAL (bronchoalveolar lavage) fluid and tissue collection.

Un modello di trapianto di polmone di ratto di ischemia calda / danno da riperfusione: ottimizzazioni per migliorare i risultati

From our experience with rat lung transplantation, we have found several areas for improvement. Information in the existing literature regarding methods ...

An Effective Mouse Model of Unilateral Renal Ischemia-Reperfusion Injury

Ischemia-reperfusion injury (IRI) is the leading cause of acute renal failure and is a significant contributor to delayed graft function. Animal models are the only available resources that mimic the complexities of the IRI-associated damage encountered in vivo. This paper describes an effective mouse model of unilateral renal IRI that delivers highly reproducible data. Ischemia is induced by occluding the right renal pedicle for 30 min followed by reperfusion. In addition to the surgical procedure, a sequential overview of the expected physiological and histopathological changes following renal IRI will be provided by comparing data from seven different reperfusion times (4 h, 8 h, 16 h, 1 day, 2 days, 4 days, and 7 days). Critical data for planning experiments ahead, such as mean surgical time, average anesthetic consumption, and body weight changes over time, will be shared. This work will help researchers implement a reliable renal IRI model and select the appropriate reperfusion time that aligns with their intended investigative goals.

Renal ischemia-reperfusion injury is associated with high morbidity and mortality in hospitalized patients. Here, we present a simple and effective mouse model of unilateral renal ischemia-reperfusion injury and provide a sequential overview of representative pathological changes observed in the kidney.

Un modello murino efficace di danno unilaterale da ischemia-riperfusione renale

Ischemia-reperfusion injury (IRI) is the leading cause of acute renal failure and is a significant contributor to delayed graft function. Animal models ...

A Piglet Perinatal Asphyxia Model to Study Cardiac Injury and Hemodynamics after Cardiac Arrest, Resuscitation, and the Return of Spontaneous Circulation

Neonatal piglets have been extensively used as translational models for perinatal asphyxia. In 2007, we adapted a well-established piglet asphyxia model by introducing cardiac arrest. This enabled us to study the impact of severe asphyxia on key outcomes, including the time taken for the return of spontaneous circulation (ROSC), as well as the effect of chest compressions according to alternative protocols for cardiopulmonary resuscitation. Due to the anatomical and physiological similarities between piglets and human neonates, piglets serve as good models in studies of cardiopulmonary resuscitation and hemodynamic monitoring. In fact, this cardiac arrest model has provided evidence for guideline development through research on resuscitation protocols, pathophysiology, biomarkers, and novel methods for hemodynamic monitoring. Notably, the incidental finding that a substantial fraction of piglets have pulseless electrical activity (PEA) during cardiac arrest may increase the applicability of the model (i.e., it may be used to study pathophysiology extending beyond the perinatal period). However, the model generation is technically challenging and requires various skill sets, dedicated personnel, and a fine balance of the measures, including the surgical protocols and the use of sedatives/analgesics, to ensure a reasonable rate of survival. In this paper, the protocol is described in detail, as well as experiences with adaptations to the protocol over the years.

This piglet model involves surgical instrumentation, asphyxiation until the cardiac arrest, resuscitation, and post-resuscitation observation. The model allows for multiple sampling per animal, and by using continuous invasive arterial blood pressure, ECG, and non-invasive cardiac output monitoring, it provides knowledge about hemodynamics and cardiac pathophysiology in perinatal asphyxia and neonatal cardiopulmonary resuscitation.

Un modello di asfissia perinatale da maialino per studiare la lesione cardiaca e l'emodinamica dopo l'arresto cardiaco, la rianimazione e il ritorno della circolazione spontanea

Neonatal piglets have been extensively used as translational models for perinatal asphyxia. In 2007, we adapted a well-established piglet asphyxia model ...