title: An in vitro study of the effectiveness of carbon dioxide flushing of arterial line filters.
abstract: Gaseous microemboli (GMEs) have been connected to neurologic impairment and other ischemic complications after surgery. The components of the extracorporeal circuit (ECC) have a large influence on GME production. This in vitro study investigates the use of carbon dioxide flushing of the 38-microm Medtronic Affinity CB351 and 38-microm Medtronic Affinity 351 arterial line filters (ALFs) to decrease GMEs and time for air to clear the ALE An adult circuit was implemented with a silicone oxygenator for vacuum-assisted gas removal and to reduce air before ALE The 48 filters were separated into four equal groups: flushed coated and non-coated and non-flushed coated and non-coated. Carbon dioxide flushing was performed at 6 L/min for 3 minutes. ALFs were retrograde primed at 200 mL/min. An Emboli Detection and Classification Quantifier (EDAC) was used to gather data. The average total emboli and time to clear (seconds) for flush coated were 20.25 +/- 16.78 and 142.17 +/- 174.80 seconds, respectively, flushed non-coated were 30.5 +/- 34.65 and 124.17 +/- 131.40 seconds, non-flushed coated were 162.08 +/- 79.90 and 390.42 +/- 84.36 seconds, and non-flushed non-coated were 163.67 +/- 212.67 and 305.92 +/- 179.36 seconds. Flushed filters had an average total emboli count of 25.375 +/- 27.14 and an average time to clear of 13.167 +/- 151.51 seconds. Non-flushed filters had an average total emboli count of 162.875 +/- 157.11 and an average time to clear of 348.167 +/- 143.70 seconds. Coated and non-coated filters for total emboli and time to clear had p values of .86 and .24, respectively. Flushed and non-flushed filters had total emboli and time to clear p values of < .001 and < .001, respectively. No significant difference was found between coated and non-coated filters involving total embolic count and time to clear. A significant difference was found in total embolic count and time to clear between flushed and non-flushed filters. This study shows that fewer emboli and faster embolic clearance time correlate with carbon dioxide flushing of the ALE.
authors.affiliation: College of Health Sciences, Midwestern University, Glendale, Arizona, USA. rrbeckman@hotmail.com
authors.forename: Roland Ryan
authors.initials: RR
authors.lastname: Beckman
authors.forename: Carl
authors.initials: C
authors.lastname: Gisner
authors.forename: Ed
authors.initials: E
authors.lastname: Evans
mesh_terms: D002245:Carbon Dioxide; D002315:Cardiopulmonary Bypass / Q000295:instrumentation*; D004618:Embolism, Air / Q000517:prevention & control*; D004867:Equipment Design; D005374:Filtration / Q000295:instrumentation*; D006801:Humans; D066298:In Vitro Techniques
chemical_list: D002245:Carbon Dioxide