Sedation for children with metachromatic leukodystrophy undergoing MRI

Metachromatic leukodystrophy (MLD) is a lysosomal storage disease with infantile and juvenile onset with a poor prognosis and magnetic resonance imaging (MRI) plays a fundamental role in its diagnosis. Procedural sedation is needed to carry out MRI on children. Very few case reports have been published on anesthesia or sedation for MLD patients.

We prospectively studied 18 MLD patients undergoing sedation for brain MRI. Twenty consecutive similar-aged ASA I children undergoing MRI during the same time span for suspected seizures and exhibiting no MRI brain alteration healthy (HLT) patients were also studied for comparison. In patients up to 3 years of age (T_MLD and T_HLT groups), sedation was induced with thiopental 5 mg x kg(-1) i.v. and further 2.5 mg x kg(-1) i.v. rescue boluses were given if the sedation level was inadequate. In patients over 3 years of age (P_MLD and P_HLT groups), sedation was induced with propofol 1-1.5 mg x kg(-1) i.v. and maintained with 0.1-0.15 mg x kg(-1) x min(-1) continuous i.v. infusion, which was increased if the sedation level was inadequate. We recorded complications, if any, caused by sedation (hypoxia, vomiting, bradycardia, other major arrhythmias, convulsions, MRI artifact movements with increasing sedation, prolonged recovery).

No sedation complications occurred. The mean dose of thiopental required to warrant patient immobility was 0.227 +/- 0.053 mg x kg(-1) x min(-1) of procedure in T_MLD patients and 0.119 +/- 0.061 mg x kg(-1) x min(-1) of procedure in T_HLT patients (difference not significant). The mean dose of propofol required for immobility was 0.119 +/- 0.054 mg x kg(-1) x min(-1) of procedure in T_MLD patients and 0.115 +/- 0.043 mg x kg(-1) x min(-1) of procedure in T_HLT patients (difference not significant).

Our protocol for sedation in the MRI setting proved safe and effective in children with MLD, who do not require different doses of sedatives compared with healthy children.