Bubble trap device may lessen neurocognitive decline after CABG
MedWire News: Gaseous microembolization during coronary artery bypass graft (CABG) surgery contributes to neuropsychologic decline which is measurable 3 months after the operation, say researchers who found use of a dynamic bubble trap (DBT) filter device during the operation offered some protection against this effect.
The team reports that patients who underwent CABG with cardiopulmonary bypass (CPB) and use of the DBT device, which reduces gaseous micro-emboli by trapping gas microbubbles from the CPB arterial line, performed better in two neuropsychologic tests at follow-up than patients treated with use of an intra-aortic filter which captures solid micro-emboli or no additional device.
Noting that the DBT device is inexpensive (around US$ 20 [€14] per unit) and easy to apply, the authors say that “gas filters are recommendable for neuroprotection during cardiac surgery.”
Markus Schönburg (Justus-Liebig University Giessen, Germany) and colleagues studied 150 patients undergoing elective CABG with CPB, who they randomly assigned to receive a DBT (placed into the arterial line between the arterial filter and the arterial cannula), the Embol-X arterial filter device (inserted into the aorta), or no additional filter device during surgery (control group).
They report in the European Heart Journal that the DBT group showed improved cognitive performance on a battery of neuropsychologic tests compared with the control group at 3 month follow-up, in terms of executive functioning (p=0.0065) and verbal short-term memory (p=0.009).
In contrast, the Embol-X group did not perform better in any of these tests.
Furthermore, the total number of microemboli signals on Dopper (TCD) sonography was lower in the DBT but not the Embol-X group compared with controls.
The researchers also found a weak but significant association between the sum of micro-embolization signals and cognitive decline.
Author of an accompanying editorial, Volkmar Folk (University of Zurich, Switzerland) observed that off-pump CABG can potentially reduce the embolic load by eliminating the need for aortic cross-clamping.
He commented: “Most studies that could not find a difference between neurologic complications after on- and off-pump bypass procedures did not apply total arterial grafting and used side-biting clamps for performing the proximal anastomoses.”
Noting that a residual risk based on the patient’s underlying health status will remain, he concluded: “The combination of off-pump surgery and all arterial grafting may be the surgeon’s best tool to avoid some but not all neurologic complications after bypass surgery.”
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By Caroline Price