Relationship Between Cerebral Artery Blood Flow Velocities And Sickle Cell Severity

Abstract

INTRODUCTION

Sickle Cell Anaemia (SCA) is a chronic haemolytic state associated with recurrent blood transfusions, infections and its attendant complications. Vasocclusion results in the narrowing of the major cerebral blood vessel which predisposes children with SCA to the development of multisystem complications. Cerebral blood flow velocity can be assessed using transcranial Doppler ultrasound and the sickle cell disease severity can be assessed using scoring system by Adegoke and Kuti adopted for use in Nigeria for disease severity. The study compared the relationship between cerebral artery blood flow velocities (CBFV) and sickle cell disease severity in SCA children aged 2-16 years seen at Federal Teaching Hospital Owerri, Imo state.

METHODS

Sickle Cell Anaemia (SCA) is a chronic haemolytic state associated with recurrent blood transfusions, infections and its attendant complications. Vasocclusion results in the narrowing of the major cerebral blood vessel which predisposes children with SCA to the development of multisystem complications. Cerebral blood flow velocity can be assessed using transcranial Doppler ultrasound and the sickle cell disease severity can be assessed using scoring system by Adegoke and Kuti adopted for use in Nigeria for disease severity. he study compared the relationship between cerebral artery blood flow velocities (CBFV) and sickle cell disease severity in SCA children aged 2-16 years seen at Federal Teaching Hospital Owerri, Imo state.

RESULTS

A total of 102 subjects out of the 150 enrolled patients were screened within the study period. The values obtained from this procedure were categorized as abnormal (≥200cm/s), conditional (170 – 199cm/s) and normal or standard risk (< 170cm/s). Children with abnormal blood velocities are at high risk for CVA while children whose velocities fall within the conditional range are at moderate risk for CVAs. The prevalence of abnormal cerebral blood flow velocity of above 170cm/second was 17.6% (13.7% was at conditional risk zone and 3.9% at high risk zone). All the subjects at high risk zone were aged 2-6 years and 75% females. Ninety participants (88.2%) had mild disease while the remaining 12(11.8%) had moderately severe disease. None of the patients had a severe disease. Majority of those with mild disease had high risk for a CVA.

CONCLUSION

The prevalence of abnormal cerebral blood flow velocity in SCA children is 17.6%. Identification of subjects at risk for a CVA although with a mild disease scores helped in primary prevention by prompt therapy institution.