  Bubbles introduced to the arterial circulation during invasive medical
procedures can have devastating consequences for brain function but their
effects are currently difficult to quantify. Here we present a Monte-Carlo
simulation investigating the impact of gas bubbles on cerebral blood flow. For
the first time, this model includes realistic adhesion forces, bubble
deformation, fluid dynamical considerations, and bubble dissolution. This
allows investigation of the effects of buoyancy, solubility, and blood pressure
on embolus clearance.
  Our results illustrate that blockages depend on several factors, including
the number and size distribution of incident emboli, dissolution time and blood
pressure. We found it essential to model the deformation of bubbles to avoid
overestimation of arterial obstruction. Incorporation of buoyancy effects
within our model slightly reduced the overall level of obstruction but did not
decrease embolus clearance times. We found that higher blood pressures generate
lower levels of obstruction and improve embolus clearance. Finally, we
demonstrate the effects of gas solubility and discuss potential clinical
applications of the model.
