Assessment of Oxygen Saturation Using Pulse Oximetry in Patients with Steady State HbSS

Background: The exact consequence of hypoxemia SCA is unclear, however, many studies have shown haemoglobin desaturation is common in patient with SCA even at steady state, and may predispose to several complications including pulmonary hypertension, stroke and acute chest syndrome. Therefore, detection of hypoxemia is important in patients with SCA. Objectives: We sought to compare SpO2 of patients with HbSS in steady state and healthy individuals with HbAA genotype; and to determine the prevalence of hypoxemia amongst HbSS patients during steady state. Materials and Methods: This is a prospective cross-sectional study involving ninety three adults with SCA in steady state and forty-eight healthy age and sex matched HbAA participants as controls. The oxygen saturation was recorded using a finger pulse oximeter (Suaoki, Model FS20A). Results: The HbSS patients had a significantly lower mean SpO2 of 95.5% ( 4.1) compared to 99.06% ( 1.14) for the healthy HbAA group (p=0.0001). Male and female HbSS patients had a comparable SpO2 (95.8% vs 96.1%, p=0.610). Similarly, mean SpO2 was similar in male and female HbAA group (p=0.258). The prevalence of hypoxemia among the HbSS patients was 30.25% compared to 2.7% amongst the HbAA. The lowest SpO2 recorded among the HbSS patients was 88%. Conclusion: The prevalence of hypoxemia in steady state HbSS patients was high. This finding underscores the importance of monitoring HbSS patients for prompt detection of hypoxemia, and to institute therapy where necessary to prevent complications including pulmonary hypertension and cerebrovascular disease.