Comparing Between CO2 and Phenylephrine Treatment in Patients With Progressive Lacunar Infarction (CARBOGEN Study)

Lacunar infarction is an ischemic stroke occurred by small perforating artery occlusion . Twenty percent of ischemic stroke is lacunar infarction.

However, outcome of lacunar infarction is excellent, about 20-40% patients are suffered neurological worsening.

Progressive lacunar infarction is associated poor functional outcome and neurological deficit.

Currently, no treatment for progressive lacunar infarction is recommended on the guideline.

Several small study reported that phenylephrine and magnesium may be helpful for progressive lacunar infarction.

Carbogen is a mixture of 5% CO2 with 95% O2. Carbogen is safe and it is used for the treatment of sudden sensory neural hearing loss or ocular ischemia.

CO2 dilate cerebral arteriole and concentration of CO2 is correlated with cerebral blood flow.

Lacunar infarction is small and perfused with marginal flow by neighboring perforating arteriole.

Increased cerebral blood flow following dilation of cerebral arteriole by CO2 might halt and revert progressive lacunar infarction.

Induced hypertension is alternative treatment of progressive lacunar infarction. Increasing blood pressure also induce cerebral blood flow.

Phenylephrine is an α1 agonist, phenylephrine act on peripheral artery and little effect on cerebral artery or heart.

Several studies reported that the effectiveness of phenylephrine on progressing stroke.

Therefore, this study will compare the effectiveness of carbogen versus phenylephrine in lacunar infarction patients who suffered neurological worsening.