Whilst still relatively uncommon in Australia the incidence of Sickle Cell Disease (SCD) is likely to increase as migrants from the Mediterranean, sub continental Asia and Africa become more numerous.
SCD provides a unique set of challenges for the anaesthetist and surgical team and this review will describe the pathophysiology and natural history of SCD, and then consider the current evidence for anaesthetic management of such cases.
This PBLD will help reinforce the review of Anaesthesia and Sickle Cell Disease which is also posted online. Please read this review first by following this link which will open in a new window.
Anaesthesia and Sickle Cell Disease Review
Tetramer consisting of 2α and 2β chains. Each chain enfolding a haem moeity. Oxygen reversibly binds to the ferric(Fe2+) iron molecule.
Exterior is highly polar (water soluble), whilst interior hydrophobic.
Most important purpose = oxygen transport.
Genotypes --> HbA;2α2β, HbA2;2 α2δ, HbF;2 α 2 ϒ
Normal concentrations HbA – 95%, HbA2 – 2.5%, HbF – 2.5%
Haemoglobin is a tetramer with 4 haem moeity’s, oxygen binds to each of the iron molecules. Hence 4 molecules of oxygen will bind to each molecule of haemoglobin.
Which is the correct statement regarding causes of a RIGHT shift in the oxygen dissociation curve?
Source: West JB, Respiratory Physiology: The Essentials. 7th Ed. Lippincott Williams & Wilkins 2005. Maryland USA.
Answer E is simply the genotype of sickle cell trait
Source: Firth PG, Head CA. Sickle cell disease and anesthesia. Anesthesiology. 2004;101(3):766–85. (p767 for answer)
Source: Umoh AV, Abah GM, Ekanem TI and Essien EM. Haemoglobin genotypes: a prevalence study and implications for reproductive health in Uyo, Nigeria. Niger J Med. 2010;19(1):36-41.
Question Knowledge Base
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Source: Platt O, Thorington BD, Brambilla DJ, Milner PF, Rosse W, Vichinsky E, et al. Pain in sickle cell disease: rates and risk factors. New Engl J Med 1991;325:11–6.
Source: Wilson M, Forsyth P, Whiteside J. Haemoglobinopathy and sickle cell disease. Continuing Education in Anaesthesia, Critical Care and Pain 2010;Volume 10 Number 1; 24-28.
Source: Smiers FJ, Krishnamurti L, Lucarelli G. Hematopoietic Stem Cell Transplantation for Hemoglobinopathies: Current Practice and emerging trends. Pediatr Clin N Am 2010;57:181-205.
Source: Fitzgerald RK, Johnson A. Pulse oximetry in sickle cell anemia. Crit Care Med 2001;29(9):1803–6.
Source: Al Jama FE et al. Pregnancy outcome in patients with homozygous SCD in a university hospital, Eastern Saudi Arabia. Arch Gynecol Obstet 2009; 280:793-797.
Source: Milner PF, Kraus AP, Sebes JI, Sleeper LA, Dukes KA, Embury SH, et al. Sickle cell disease as a cause of osteonecrosis of the femoral head. New Engl J Med 1991;325:1476–81.
Source: Platt OS, Brambilla DJ, Rosse WF, Milner PF et al. Mortality in sickle cell disease, life expectancy and risk factors for early death. N Engl J Med 1994;330(23):1639-44.