Study on evaluation of arterial oxygen saturation levels using pulse oximetry in subjects with sickle cell disease

Background: Pulse oximeters are cheap, rapid and widely used non-invasive, point-of care testing devices widely used in clinical practice for estimating arterial oxyhemoglobin saturation, denoted by SpO2. SCD is a common hereditary hemoglobinpathy that occurs primarily in individuals of African Americans, Arabian and Indian descent. Sickle Cell Disease (SCD) is the major health problem in Chhattisgarh Population. Many studies showed haemoglobin desaturation to be common in patient with sickle cell anaemia (SCA) even at steady state. Objectives of the study: To measure SpO2 levels, liver function tests in steady state sickle cell disease subjects both homozygous and heterozygous (HbSS and HbAS) and to compare SpO2 levels between sickle cell disease subjects and healthy controls and to measure the prevalence of hypoxemia in sickle cell disease subjects.Methods:100 diagnosed and HPLC confirmed cases of SCD (HbSS and HbAS) along with 100 age and gender matched controls were involved in the study. In the subjects when seated, a semi-disposable oximeter sensor was applied to the index finger of the non-dominant hand, after ensuring that nail polish was not present, and was then attached to the oximeter and 5mL of random blood sample was drawn for biochemical analysis (liver function tests) after taking consent from the patients. Results: In the present study, we found low oxygen saturation and high prevalence of hypoxemia (SpO2 <96%) in sickle cell disease subjects as compared to healthy controls. The serum total bilirubin, direct bilirubin, indirect bilirubin, aspartate transaminase (AST) and alanine transaminase (ALT) levels were significantly higher in SCD patients (P <0.001) than in controls. Conclusion: It is recommended that a simple, rapid, non-invasive pulse oximetry measurement of SpO2 in these subjects could be highly useful to detect early the chances of hypoxemia and hence therapy can be instituted and it is advisable that liver function tests be interpreted with caution in these patients. SCD patients require serial monitoring of these parameters during their routine visits to the hospital.