नवजात श्वासावरोध के एक सूअर मॉडल
Summary
बड़े पशु मॉडल और नवजात श्वासावरोध के फिजियोलॉजी और औषध विज्ञान की परीक्षा में अच्छा translational मूल्यों है. नवजात piglets का उपयोग करना, हम नवजात श्वासावरोध जो प्रणालीगत और क्षेत्रीय hemodynamics, जैव रासायनिक और वैकृत रास्ते और correlations के साथ ऑक्सीजन परिवहन का अध्ययन करने के फायदे हैं अनुकरण के लिए एक प्रयोगात्मक प्रोटोकॉल विकसित.
Abstract
Annually more than 1 million neonates die worldwide as related to asphyxia. Asphyxiated neonates commonly have multi-organ failure including hypotension, perfusion deficit, hypoxic-ischemic encephalopathy, pulmonary hypertension, vasculopathic enterocolitis, renal failure and thrombo-embolic complications. Animal models are developed to help us understand the patho-physiology and pharmacology of neonatal asphyxia. In comparison to rodents and newborn lambs, the newborn piglet has been proven to be a valuable model. The newborn piglet has several advantages including similar development as that of 36-38 weeks human fetus with comparable body systems, large body size (˜1.5-2 kg at birth) that allows the instrumentation and monitoring of the animal and controls the confounding variables of hypoxia and hemodynamic derangements.
We here describe an experimental protocol to simulate neonatal asphyxia and allow us to examine the systemic and regional hemodynamic changes during the asphyxiating and reoxygenation process as well as the respective effects of interventions. Further, the model has the advantage of studying multi-organ failure or dysfunction simultaneously and the interaction with various body systems. The experimental model is a non-survival procedure that involves the surgical instrumentation of newborn piglets (1-3 day-old and 1.5-2.5 kg weight, mixed breed) to allow the establishment of mechanical ventilation, vascular (arterial and central venous) access and the placement of catheters and flow probes (Transonic Inc.) for the continuously monitoring of intra-vascular pressure and blood flow across different arteries including main pulmonary, common carotid, superior mesenteric and left renal arteries. Using these surgically instrumented piglets, after stabilization for 30-60 minutes as defined by Z<10% variation in hemodynamic parameters and normal blood gases, we commence an experimental protocol of severe hypoxemia which is induced via normocapnic alveolar hypoxia. The piglet is ventilated with 10-15% oxygen by increasing the inhaled concentration of nitrogen gas for 2h, aiming for arterial oxygen saturations of 30-40%. This degree of hypoxemia will produce clinical asphyxia with severe metabolic acidosis, systemic hypotension and cardiogenic shock with hypoperfusion to vital organs. The hypoxia is followed by reoxygenation with 100% oxygen for 0.5h and then 21% oxygen for 3.5h. Pharmacologic interventions can be introduced in due course and their effects investigated in a blinded, block-randomized fashion.
Protocol
Discussion
वर्तमान प्रयोगात्मक प्रोटोकॉल लिए hypoxia और reoxygenation प्रक्रिया के दौरान नवजात विषयों में प्रणालीगत और क्षेत्रीय hemodynamic परिवर्तन की जांच के लिए एक लाभ है. हम भी वसूली के दौरान हृदय समारोह में सुधार करने के लिए इ…
Divulgations
The authors have nothing to disclose.
Acknowledgements
लेखकों के मेडिकल रिसर्च के लिए ऑपरेटिंग अनुदान और स्थापना निधि के लिए स्वास्थ्य (MOP53116) अनुसंधान और अलबर्टा विरासत फाउंडेशन की कनाडा के संस्थानों का धन्यवाद करना चाहते हैं, क्रमशः होगा, इस प्रयोगात्मक मॉडल के विकास का समर्थन.
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