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Title: Automated Balloon Guide Catheter Aspiration Using an iPad App and Bluetooth-enabled Smart Pump: In-vitro Study.
Multiple studies suggest that addition of cervical balloon guide catheter (BGC) aspiration to intracranial suction aspiration or thrombectomy improves outcomes (1). Currently, stroke thrombectomy when performed with cervical BGC/Guide catheter (GC) aspiration requires two (2) operators. Utilizing an automated smart pump could enable a single (1) operator to perform BGC-assisted thrombectomy while varying the suction intensity in different segments of the intracranial and cervical vasculature. Phase 1: Staged BGC aspiration (initially low, medium, then high - to avoid vessel collapse) is manually performed using a 60cc syringe and a 9F BGC. The suction intensity levels for low, medium, and high (in inHg) are measured using a vacuum gauge (2). Phase 2: the Mean suction levels and duration from three sample measurements are entered into an iPad app (CLEARTM Pro, Insera Therapeutics, Inc.) to create a suction pattern. Phase 3: With a BGC positioned in an in-vitro flow model simulating stroke thrombectomy, the feasibility of automated staged BGC aspiration is assessed. The iPad app activates a bluetooth-enabled smart pump (CLEARTM Aspiration System, Insera Therapeutics, Inc.) connected to the BGC. Phase 1 testing was performed. Low suction ranged from 10-13 inHg (Mean: 12 inHg) with a duration ranging from 11-17s (Mean: 13s), Medium suction ranged from 15-18 inHg (Mean: 16 inHg) with a duration ranging from 8-11s (Mean: 9s), High suction ranged from 24-26 inHg (Mean: 25 inHg) with a duration ranging from 19-25s (Mean: 22s), The total duration of staged BGC aspiration ranged from 39-53s with a 60s safety pause or end of suction prior to another retrieval attempt. Phases 2 & 3 were successfully performed to create a customized BGC pattern and staged BGC aspiration was automated during simulated stroke thrombectomy. Automated staged BGC or GC aspiration is feasible using a customizable iPad app and a bluetooth-enabled smart pump. Funding Source: This study was funded in part by a research grant (NSF Award: 1819491; PI: Vallabh Janardhan, MD) from the National Science Foundation (NSF). Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. Conference Proceeding: This paper was presented in part at the 2018 Annual Meeting of the Society of Vascular & Interventional Neurology (SVIN), November 14-17, 2018 in San Diego, CA  more » « less
Award ID(s):
1819491
NSF-PAR ID:
10132844
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Society of Vascular & Interventional Neurology (SVIN)
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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  1. Purpose: Multiple studies suggest that addition of cervical balloon guide catheter (BGC) aspiration to intracranial suction aspiration or thrombectomy improves outcomes (1). Currently, stroke thrombectomy when performed with cervical BGC/Guide catheter (GC) aspiration requires two (2) operators. Utilizing an automated smart pump could enable a single (1) operator to perform BGC-assisted thrombectomy while varying the suction intensity in different segments of the intracranial and cervical vasculature. Methods: Phase 1: Staged BGC aspiration (initially low, medium, then high - to avoid vessel collapse) is manually performed using a 60cc syringe and a 9F BGC. The suction intensity levels for low, medium, and high (in inHg) are measured using a vacuum gauge (2). Phase 2: the Mean suction levels and duration from three sample measurements are entered into an iPad app (CLEARTM Pro, Insera Therapeutics, Inc.) to create a suction pattern. Phase 3: With a BGC positioned in an in-vitro flow model simulating stroke thrombectomy, the feasibility of automated staged BGC aspiration is assessed. The iPad app activates a bluetooth-enabled smart pump (CLEARTM Aspiration System, Insera Therapeutics, Inc.) connected to the BGC. Results: Phase 1 testing was performed. Low suction ranged from 10-13 inHg (Mean: 12 inHg) with a duration ranging from 11-17s (Mean: 13s), Medium suction ranged from 15-18 inHg (Mean: 16 inHg) with a duration ranging from 8-11s (Mean: 9s), High suction ranged from 24-26 inHg (Mean: 25 inHg) with a duration ranging from 19-25s (Mean: 22s), The total duration of staged BGC aspiration ranged from 39-53s with a 60s safety pause or end of suction prior to another retrieval attempt. Phases 2 & 3 were successfully performed to create a customized BGC pattern and staged BGC aspiration was automated during simulated stroke thrombectomy. Conclusions: Automated staged BGC or GC aspiration is feasible using a customizable iPad app and a bluetooth-enabled smart pump. Funding Source: This study was funded in part by a research grant (NSF Award: 1819491; PI: Vallabh Janardhan, MD) from the National Science Foundation (NSF). Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. Conference Proceeding: This paper was presented in part at the 15th Annual Meeting of the Society of Neuro-Interventional Surgery (SNIS), July 23-26, 2018 in San Francisco, CA. 
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  2. Background: Aspiration is an important part of stroke thrombectomy (1). Pre-clinical studies have also suggested that uniform aspiration may need to be customized for varying vessel diameters and that cyclical (varying suction intensity) aspiration may be more effective (2). Methods: Suction intensity and duration are customized in an iPad app to create uniform aspiration (using the CLEAR TM App, Insera Therapeutics) or cyclical (using the CLEAR Pro TM App, Insera Therapeutics) aspiration. Customized aspiration initiated via the iPad app activates a Bluetooth-enabled smart pump (CLEAR Aspiration System TM, Insera Therapeutics) connected to a standard aspiration catheter with an inner diameter (ID) of 0.070" and length of 131 cm was studied. The suction intensity at the catheter tip is confirmed using a vacuum gauge (DuraChoice) and a previously defined technique (3), and any catheter luminal collapse is noted in an in-vitro flow model (United Biologics) simulating stroke thrombectomy. Results: Activating the smart pump to generate customized uniform and cyclical aspiration (suction range 0 to -29 in Hg) using an iPad app was successful. A vacuum gauge at the catheter tip confirmed the varying suction intensities generated by the smart pump without any catheter lumen collapse. Low, medium and high suction intensities of -13, -21, and -29 inHg on the digital smart pump resulted in a suction intensities at the catheter tip of -12.5, -20.5, and -28.5 inHg. Pause of 0 inHg on the digital smart pump resulted in similar intensity at catheter tip. There was similar transmission of suction intensities between the digital smart pump and the catheter tip for uniform and cyclical aspiration patterns. Conclusion: It is feasible to customize uniform and cyclical aspiration using a digital smart pump. Further studies need to evaluate the impact of customizing uniform and cyclical aspiration on varying vessel diameters, clot types, and clot burden. Funding Source: This study was funded in part by a research grant (NSF Award: 1819491; PI: Vallabh Janardhan, MD) from the National Science Foundation (NSF). Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. Conference Proceeding: This paper was presented in part at the 2018 Annual Meeting of the Society of Vascular & Interventional Neurology (SVIN), November 14-17, 2018 in San Diego, CA 
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