Has anyone taken legal action towards big hospitals like Apollo, Care or Yashoda? Is it possible?

My sister was grossly mistreated and shifted to ICU against her doctors orders by the floor doctor in charge and nurses, it was a neuro icu where they had terminal patients, DNR patients and ECMO patients, she had no need to be in the ICU and spent 5 hrs traumatized in there thinking she was as critical as them (she is 25, and was admitted in the icu as the nurses thought she had low platelets, without doing a blood picture after her platelet infusion, which we requested multiple times) once we came back home my sister has been in a daze and keeps getting lost in thoughts from her experience and is still traumatized thinking we were hiding how serious her condition really was. Is there a basis for legal action?