Thank you for your question.
No you don't need a transfusion for a HBG of 8.4, in general.
However, you did not state what the cause of your anemia is. If you have been worked up and it is rom heavy periods or a known chronic disease and is being treated with Ferrous sulfate or whatever other medication is appropriate, a blood transfusion is entirely unnecessary.
However, if you were having a gastrointestinal bleed, they would definitely type and crossmatch you and consider doing this if your counts continued to drop.
Many years ago, you would have been given a transfusion for a low level, but not now with the incidence of hepatitis, HIV, antibody reactions, etc. It is not considered the first line of therapy.
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