surgical-technique-for-implantation-tissue-engineered-vascular-grafts

Surgical Technique for the Implantation of Tissue Engineered Vascular Grafts and Subsequent <em>In Vivo </em>Monitoring

The development of Tissue Engineered Vessels (TEVs) is advanced by the ability to routinely and effectively implant TEVs (4-5 mm in diameter) into a large ...

the-perinatal-asphyxiated-lamb-model-a-model-for-newborn-resuscitation

The Perinatal Asphyxiated Lamb Model: A Model for Newborn Resuscitation

Birth asphyxia accounts for nearly one million deaths worldwide each year, and is one of the primary causes of early neonatal morbidity and mortality. ...

State University of New York Buffalo School of Medicine

University at Buffalo

Current neonatal resuscitation guidelines recommend tracheal suctioning of nonvigorous neonates born through meconium-stained amniotic fluid.

Tracheal suctioning improves gas exchange but not hemodynamics in asphyxiated lambs with meconium aspiration.

The oxygenation index (OI = mean airway pressure, MAP × FiO2 × 100 : PaO2) is used to assess the severity of hypoxic respiratory failure (HRF) and persistent pulmonary hypertension of the newborn (PPHN). An indwelling arterial line or arterial punctures are necessary to obtain PaO2 for the calculation of OI. Oxygenation can be continuously and noninvasively assessed using pulse oximetry. The use of the oxygen saturation index (OSI = MAP × FiO2 × 100 : SpO2) can be an alternate method of assessing the severity of HRF.

Oxygen saturation index and severity of hypoxic respiratory failure.

To engineer and implant vascular grafts in the arterial circulation of a pre-clinical animal model and assess the role of donor medial cells in graft remodeling and function.

Arterial grafts exhibiting unprecedented cellular infiltration and remodeling in vivo: The role of cells in the vascular wall.

The large number of coronary artery bypass procedures necessitates development of off-the-shelf vascular grafts that do not require cell or tissue harvest from patients. However, immediate thrombus formation after implantation due to the absence of a healthy endothelium is very likely. Here we present the successful development of an acellular tissue engineered vessel (A-TEV) based on small intestinal submucosa that was functionalized sequentially with heparin and VEGF. A-TEVs were implanted into the carotid artery of an ovine model demonstrating high patency rates and significant host cell infiltration as early as one week post-implantation. At one month, a confluent and functional endothelium was present and the vascular wall showed significant infiltration of host smooth muscle cells exhibiting vascular contractility in response to vaso-agonists. After three months, the endothelium aligned in the direction of flow and the medial layer comprised of circumferentially aligned smooth muscle cells. A-TEVs demonstrated high elastin and collagen content as well as impressive mechanical properties and vascular contractility comparable to native arteries. This is the first demonstration of successful endothelialization, remodeling, and development of vascular function of a cell-free vascular graft that was implanted in the arterial circulation of a pre-clinical animal model. 

Successful endothelialization and remodeling of a cell-free small-diameter arterial graft in a large animal model.

The Neonatal Resuscitation Program (NRP) recommends upper and lower limits of preductal saturations (SpO2) extrapolated from studies in infants resuscitated in room air. These limits have not been validated in asphyxia and lung disease.

Neonatal resuscitation adhering to oxygen saturation guidelines in asphyxiated lambs with meconium aspiration.

The Neonatal Resuscitation Program (NRP) recommends close monitoring of oxygenation during the resuscitation of newborns using a pulse oximeter. However, there are no guidelines for monitoring carbon dioxide (CO2) to assess ventilation. Considering that cerebral blood flow (CBF) correlates directly with PaCO2, continuous capnography monitoring of end-tidal CO2 (ETCO2) may limit fluctuations in PaCO2 and, therefore, CBF during resuscitation of asphyxiated infants.

Continuous End-Tidal Carbon Dioxide Monitoring during Resuscitation of Asphyxiated Term Lambs.

In neonates requiring chest compression (CC) during resuscitation, neonatal resuscitation program (NRP) recommends against relying on a single feedback device such as end-tidal carbon dioxide (ETCO) or saturations (SpO) to determine return of spontaneous circulation (ROSC) until more evidence becomes available.

Continuous capnography monitoring during resuscitation in a transitional large mammalian model of asphyxial cardiac arrest.

The Neonatal Resuscitation Program recommends initial resuscitation of preterm infants with low oxygen (O) followed by titration to target preductal saturations (SpO). We studied the effect of resuscitation with titrated O on gas exchange, pulmonary, and systemic hemodynamics.

Effect of various inspired oxygen concentrations on pulmonary and systemic hemodynamics and oxygenation during resuscitation in a transitioning preterm model.

ArticleTotal : 2	Year
Publication title Cited by 9	2015
Publication title Cited by 17	2018

Article	Year
Tracheal suctioning improves gas exchange but not hemodynamics in asphyxiated lambs with meconium aspiration. Pediatric research\| PubMed ID: 25406897	2015
Oxygen saturation index and severity of hypoxic respiratory failure. Neonatology\| PubMed ID: 25592054	2015
Arterial grafts exhibiting unprecedented cellular infiltration and remodeling in vivo: The role of cells in the vascular wall. Biomaterials\| PubMed ID: 25736502	2015
Successful endothelialization and remodeling of a cell-free small-diameter arterial graft in a large animal model. Biomaterials\| PubMed ID: 26561932	2016
Neonatal resuscitation adhering to oxygen saturation guidelines in asphyxiated lambs with meconium aspiration. Pediatric research\| PubMed ID: 26672734	2016
Continuous End-Tidal Carbon Dioxide Monitoring during Resuscitation of Asphyxiated Term Lambs. Neonatology\| PubMed ID: 26866711	2016
Continuous capnography monitoring during resuscitation in a transitional large mammalian model of asphyxial cardiac arrest. Pediatric research\| PubMed ID: 28157836	2017
Effect of various inspired oxygen concentrations on pulmonary and systemic hemodynamics and oxygenation during resuscitation in a transitioning preterm model. Pediatric research\| PubMed ID: 29967523	2018

Carmon Koenigsknecht

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