Anemia

Anemia can be caused by many things but first we should get some basic labs such as CBC that will show MCV, and Reticulocyte count. 

This table from UTD summarizes on the different causes of anemia depending on the MCV.

Increased reticulocyte count (increased red cell breakdown) will also require peripheral smear to narrow differential. 

1. Acute blood loss 
2. Hemolysis - including antibody mediated, cellular toxins (malaria, clostridium), trauma (valve), or hypersplenism. 
3. Intrinsic Defect- including enzyme deficiency such as G6PHD, SCD, or thalassemia 
4. Membrane Defect- including spur cell, hereditary spherocytosis or PNH

Anemia with decreased reticulocyte count 

1. Deficiency of Iron, Vit B12, Folate, or copper
2. Medication that can suppress the bone marrow (such as quinidine, TMP SMX, albendazole)
3. Primary bone marrow disorders (MDS, Myelofibrosis, or leukemia)
4. Very recent bleeding (within 5-7 days, before bone marrow compensation has occurred)

If patient has Hgb of <7 in Non cardiac patient or <8 in cardiac patient we should consider blood transfusion (pRBC).  (Let the patient know of the risk's and benefits and also inquire that patient is not a Jehovah's Witness before proceeding with blood transfusion).