Air Embolism During TEVAR: Liquid Perfluorocarbon Absorbs Carbon Dioxide in a Combined Flushing Technique and Decreases the Amount of Gas Released From Thoracic Stent-Grafts During Deployment in an Experimental Setting

Abstract

To investigate the influence of flushing thoracic stent-grafts with carbon dioxide and perfluorocarbon on the amount of gas released during stent-graft deployment in thoracic endovascular aortic repair (TEVAR). Materials and Methods: Ten TX2 ProForm thoracic stent-grafts were deployed into a water-filled container with a curved plastic pipe and flushed sequentially with carbon dioxide, 20 mL of liquid perfluorocarbon (PFC), and 60 mL of saline. Released gas was measured using a calibrated setup. The volume of released gas was compared with the results of an earlier published reference group, in which identical stent-grafts were flushed with 60 mL saline alone as recommended in the instructions for use. Results: The average amount of gas released in the test group was 0.076 mL, significantly lower (p<0.001) than the mean 0.79 mL of gas released in the reference group. Big bubbles appearing at the tip of the sheath when deployment was started were seen in all grafts of the reference group but in only 2 of the test group stent-grafts. Small bubbles were less frequent in the test group. Conclusion: The amount of gas released from thoracic stent-grafts during deployment can be influenced by different flushing techniques. The use of PFC in addition to the carbon dioxide flushing technique reduces the volume of gas released during deployment of tubular thoracic stent-grafts to a few microliters. This significant effect is presumably based on the high solubility of carbon dioxide in perfluorocarbon and could be a potential future approach to lower the risk of cerebral injury and stroke from air embolism during TEVAR.

Cerebral embolization, silent cerebral infarction and neurocognitive decline after thoracic endovascular aortic repair

“…A dynamic bubble trap designed to reduce gaseous emboli has been shown to reduce TCD HITS, and cognitive function 3 months after surgery was significantly better compared with that in control patients undergoing coronary artery bypass grafting 40 . It has also been demonstrated that thoracic endografts release significant amounts of air during deployment if flushed according to the instructions for use, and carbon dioxide flushing before standard saline flushing significantly reduces the amount of gas released 41 . This may have a potential role in reducing air embolism during TEVAR, particularly in more proximal landing zones 42 .…”

Distribution of Air Embolization During TEVAR Depends on Landing Zone: Insights From a Pulsatile Flow Model

“…Released air from the stent-graft was collected in the supra-aortic branches separately with 1-mL syringes and measured in 0.01-mL increments, as previously reported. 9 The air from the ascending and descending aorta was collected separately with a catheter and measured with a 1-mL syringe ( Figure 2).…”

“…6 Recent in vitro studies demonstrated air release from angiographic catheters and during deployment of different TEVAR devices, with a potential risk for air embolization in the supra-aortic arteries. [7][8][9] Grover et al 10 showed in vivo that 90% of MES in MCA during TEVAR are caused by air emboli, and the highest number was measured during stentgraft deployment.…”

Aneurysmen des Aortenbogens: Interventionelle Therapie

“…Eine wesentliche Rolle kommt aber auch der Freisetzung der Stentgrafts zu: durch die aufwändige Verpackung der Stentgrafts in den Schleusenhülsen kann auch eine sorgfältige Spülung der Prothese keine vollständige Entlüftung erreichen. Aus diesem Grund wurde eine Technik der zusätzlichen CO2-Spülung entwickelt, mit der die Rate an Luftembolien deutlich reduziert werden konnte (Kölbel et al 2016;Rohlffs et al 2018Rohlffs et al , 2019.…”