Hi Sammytorronto,
1. It's not easy to calculate increase in S. Ferritin level after a Ts. But every Tx add apprx. 200-250mg iron to body. For ease u can calculate like 1gm Desferal remove THEORITICALLY 85 mg iron, L1 500 mg remove 4-7 mg iron.
2 & 3 .It depend on spleen function , size etc. Generally requiremt is 2 -4 Tx monthly.
Accurately one need RBC upto 20ml/kg/month or 225ml/kg/year.