Thalassemia
Anesthesia Implications
Anesthesia Implications
Assess the severity – The primary focus on these patients is assessing the form of thalassemia and the severity of symptoms. Mild thalassemia will result in a chronic compensated anemia. Severe forms of this disease can cause/contribute to serious anemia, splenomegaly, hepatomegaly, skeletal malformations, congestive heart failure, and intellectual impairment.
Difficult intubation risk – If skeletal malformations are present
Regional anesthesia difficulty risk – If skeletal malformations are present
Anemia Risk – Unless contraindicated, give the patient 100% O2 and ensure proper ventilation. If life-threatening, administer packed red blood cells (PBRCs). Avoid nitrous oxide – nitrous oxide impairs vitamin B-12 activity, which can further contribute to anemia.
Pathophysiology
Thalassemia is a hereditary blood disorder in which the body makes an abnormal form or inadequate amount of hemoglobin. The disorder results in large numbers of red blood cells being destroyed, which leads to microcytic anemia.
Two proteins compose hemoglobin: Alpha globin and beta globin. Defects in one of the genes that helps control production of one of these proteins leads to thalassemia.
Three forms exist: Thalassemia minor, Thalassemia intermedia, and Thalassemia major.
Thalassemia minor implies that the gene was passed by only on parent (heterozygous) and the patient only carries the disease. This form is typically symptom-free
Thalassemia intermedia implies that the gene was passed by both parents (homozygous). This form can have moderate to severe symptoms.
Thalassemia major (otherwise known as Cooley Anemia) implies that the gene was passed by both parents (homozygous). This form is severe and may result in multiple transfusions in infancy.
Risk factors include family history and Asian, Chinese, Mediterranean, or African American ethnicity.
Hines. Stoelting’s anesthesia and co-existing disease. 7th edition. 2018. p. 479-480