What is a transfusion and how often would a patient get one?

What is transfusion and how often would a patient get one? Transfusion is one of the most important supportive treatments that we offer for particularly like low risk MDS patients with anemia that are not responding to the treatments. So based on how low the hemoglobin is, based on the symptoms, they get transfusions every two weeks, three weeks. And it is not just the number but the symptoms that the patients are having that dictate how frequently they need transfusions.