Seroma after arm liposuction with multiple needle aspiration. What do you think about the sclerosing injection to solve seroma?

I have never used sclerosing agents for this application.  You are too early after this surgery to be worried about sclerosing the area.  These volumes you had aspirated are super small.  Serums can be hundreds to thousands of cc.  This should resolve without sclerosis.

Having a seroma after lipo is relatively unusual.  It is much more common after an arm lift where lymphatics are cut.  I generally would recommend aspirating the seroma multiple times prior to sclerosis.  That being said, if you have had a bunch of aspirations the choices would include excision of the capsule versus injecting a sclerosant.  Best of luck.

Seromas can happen and nearly always respond to time and simple aspiration.  Your drainage amount is decreasing so stick with that and don't complicate things by adding the sclerosing agent.   Simple is best.