scholarly journals A novel roller pump for physiological flow

2020 ◽  
Vol 44 (8) ◽  
pp. 818-826
Author(s):  
Albert Chong ◽  
Zhonghua Sun ◽  
Lennart van de Velde ◽  
Shirley Jansen ◽  
Michel Versluis ◽  
...  
2018 ◽  
Vol 14 (6) ◽  
pp. 481-502 ◽  
Author(s):  
Anber Saleem ◽  
Sadia Waheed ◽  
Sohail Nadeem

Perfusion ◽  
2021 ◽  
pp. 026765912199618
Author(s):  
Mirko Kaluza ◽  
Benjamin May ◽  
Torsten Doenst

Objective: The COVID-19 pandemic requires thinking about alternatives to establish ECMO when often-limited hardware resources are exhausted. Heart-lung-machines may potentially be used for ECMO but contain roller pumps as compared to centrifugal pumps in ECMO-circuits. We here tested roller pumps as rescue pump for ECMO-establishment. Methods: We set up in vitro circuits on roller pumps from C5 heart-lung-machine with 5 l/minutes flow. In two series, we placed either PVC or silicon tubing for an ECMO circuit into the roller pump. We assessed the mechanical stress on the tubing (aiming to run the pump for at least 1 week), measured the temperature increase generated by the friction and assessed flow characteristics and its measurement in simulated situations resembling tube kinking and suction. Results: The roller pumps led to expected and unexpected adverse events. PVC tubing burst between 36 and 78 hours, while silicon tubing lasted for at least 7 days. At 7 days, the silicone tubing showed significant signs of roller pump wear visible on the outside. The inside, however, was free of surface irregularities. Using these tubings in a roller pump led to a remarkable increase in circuit temperature (PVC: +12.0°C, silicone +2.9°C). Kinking or suction on the device caused the expected dramatic flow reduction (as assessed by direct measurement) while the roller pump display continued to show the preset flow. The roller pump is therefore not able to reliably determine the true flow rate. Conclusion: Roller pumps with silicone tubing but not PVC tubing may be used for running ECMO circuits. Silicone tubing may endure the roller pump shear forces for up to 1 week. Thus, repeated tubing repositioning may be a solution. Circuit heating and substantial limitations in flow detection should increase attention if clinical use in situations of crisis is considered.


2000 ◽  
Author(s):  
Hai-Chao Han ◽  
Raymond P. Vito ◽  
Kristin Michael ◽  
David N. Ku

Abstract To study the effect of axial stretch on vascular function and wall remodeling, porcine carotid arteries were cultured under conditions of physiological flow and elevated axial stretch in an ex vivo organ culture system. Smooth muscle cell proliferation was measured by bromodeoxyuridine index. Results showed that cell proliferation was significantly increased in the highly stretched arteries when compared to the normally stretched arteries. This may indicate the feasibility of stimulating new arterial growth by stretching natural arteries.


2020 ◽  
pp. 1-8 ◽  
Author(s):  
Adithya S. Reddy ◽  
Yang Liu ◽  
Joshua Cockrum ◽  
Daniel Gebrezgiabhier ◽  
Evan Davis ◽  
...  

OBJECTIVEThe development of new endovascular technologies and techniques for mechanical thrombectomy in stroke has greatly relied on benchtop simulators. This paper presents an affordable, versatile, and realistic benchtop simulation model for stroke.METHODSA test bed for embolic occlusion of cerebrovascular arteries and mechanical thrombectomy was developed with 3D-printed and commercially available cerebrovascular phantoms, a customized hydraulic system to generate physiological flow rate and pressure, and 2 types of embolus analogs (elastic and fragment-prone) capable of causing embolic occlusions under physiological flow.RESULTSThe test bed was highly versatile and allowed realistic, radiation-free mechanical thrombectomy for stroke due to large-vessel occlusion with rapid exchange of geometries and phantom types. Of the transparent cerebrovascular phantoms tested, the 3D-printed phantom was the easiest to manufacture, the glass model offered the best visibility of the interaction between embolus and thrombectomy device, and the flexible model most accurately mimicked the endovascular system during device navigation. None of the phantoms modeled branches smaller than 1 mm or perforating arteries, and none underwent realistic deformation or luminal collapse from device manipulation or vacuum. The hydraulic system created physiological flow rate and pressure leading to iatrogenic embolization during thrombectomy in all phantoms. Embolus analogs with known fabrication technique, structure, and tensile strength were introduced and consistently occluded the middle cerebral artery bifurcation under physiological flow, and their interaction with the device was accurately visualized.CONCLUSIONSThe test bed presented in this study is a low-cost, comprehensive, realistic, and versatile platform that enabled high-quality analysis of embolus–device interaction in multiple cerebrovascular phantoms and embolus analogs.


1992 ◽  
Vol 21 (5) ◽  
pp. 510-514
Author(s):  
Hajime OHZEKI ◽  
Satosi NAKAZAWA ◽  
Akira SAITO ◽  
Hisanaga MORO ◽  
Hirofumi OKAZAKI ◽  
...  

1983 ◽  
Vol 7 (1) ◽  
pp. 49-54 ◽  
Author(s):  
George P. Noon ◽  
James E. Harrell ◽  
Louis Feldman ◽  
Julie Peterson ◽  
Patricia M. Kent ◽  
...  

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