OBJECTIVES/GOALS: For patients suffering from respiratory failure there are limited options to support gas exchange aside from mechanical ventilation. Our goal is to design, investigate, and refine a novel device for extrapulmonary gas exchange via peritoneal perfusion with perfluorocarbons (PFC) in an animal model. METHODS/STUDY POPULATION: Hypoxic respiratory failure will be modeled using 50 kg swine mechanically ventilated with subatmospheric (10-12%) oxygen. Through a midline laparotomy, two cannulas, one for inflow and one for outflow, will be placed into the peritoneal space. After abdominal closure, the cannulas will be connected to a device capable of draining, oxygenating, regulating temperature, filtering, and pumping perfluorodecalin at a rate of 3-4 liters per minute. During induced hypoxia, the physiologic response to PFC circulation through the peritoneal space will be monitored with invasive (e.g. arterial and venous blood gases) and non-invasive measurements (e.g. pulse oximetry). RESULTS/ANTICIPATED RESULTS: We anticipate that the initiation of oxygenated perfluorocarbons perfusion through the peritoneal space during induced hypoxia will create an increase in hemoglobin oxygen saturation and partial pressure of oxygen in arterial blood. As we expect gas exchange to be occurring in the microvascular beds of the peritoneal membrane, we expect to observe an increase in the venous blood oxygen content sampled from the inferior vena cava. Using other invasive hemodynamic measures (e.g. cardiac output) and blood samples taken from multiple venous sites, a quantifiable rate of oxygen delivery will be calculable. DISCUSSION/SIGNIFICANCE: Peritoneal perfluorocarbon perfusion, if able to deliver significant amounts of oxygen, would provide a potentially lifesaving therapy for patients in respiratory failure who are unable to be supported with mechanical ventilation alone, and are not candidates for extracorporeal membrane oxygenation.
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Hypothermic Peritoneal Perfusion of Cold Oxygenated Perfluorocarbon May Improve The Efficacy of Extracorporeal Oxygenation: A Mathematical Model-Based Analysis
Abstract Circulation of perfluorocarbon (PFC) through corporeal cavities has received interest by virtue of its potential to supplement oxygenation via mechanical ventilation. However, the technology is not mature enough for clinical application, due to the knowledge gaps regarding the limiting factors hampering oxygen transport from PFC to blood. In this paper, we investigate a novel hypothesis that hypothermic peritoneal perfusion of cold oxygenated PFC may improve oxygenation of blood by facilitating the diffusion of oxygen from PFC to blood. Our hypothesis originates from physics-inspired insights that both hypothermia and PFC cooling may increase PFC-to-blood oxygen tension gradient: (i) hypothermia may decrease venous oxygen tension while (ii) cooling PFC may increase oxygen tension therein by increasing its oxygen solubility. Using a physics-based mathematical model capable of simulating oxygen tension responses to mechanical ventilation and peritoneal PFC perfusion under normothermic and hypothermic conditions, we analyzed the effect of hypothermic peritoneal cold PFC perfusion on blood oxygenation. The results predicted that peripheral oxygen saturation may be improved by 5%-10% by peritoneal perfusion of oxygenated 15°C PFC at 32°C body temperature compared with peritoneal perfusion of oxygenated 37.5°C PFC at 37.5°C body temperature. The results also predicted that cooling PFC may play a more meaningful role than hypothermia. Pending the investigation of adverse impact of hypothermia and cold PFC on homeostasis, hypothermic cold PFC perfusion may improve peritoneal oxygenation by facilitating diffusion.
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- Award ID(s):
- 2121110
- PAR ID:
- 10541317
- Publisher / Repository:
- ASME
- Date Published:
- Journal Name:
- Journal of Dynamic Systems, Measurement, and Control
- ISSN:
- 0022-0434
- Page Range / eLocation ID:
- 1 to 11
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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