Propofol for sedation in pediatric NMR-Tomography investigations

Background Magnetic Resonance Imaging requires immobilisation of the patien ts without excitement due to acoustic irritation. During childhood this is hardly to guarantee without anaesthesia or sedation. The problem is the mag netic field strength, which interferes with the monitoring devices and the anaesthesia machines interrupting the function and can produce thermal inju ry, but additionally the tools will cause image degradation. Patient and method MR Imaging was done in 46 children with a mean age of 50 .9 months (0.06 to 129) in a sedation with propofol during spontaneous brea thing. The induction dose of propofol was 3.0 mg/kg bodyweight and the repe tition dose was 1.0 mg/kg. During the radiological examination and the time of emergence the children were monitored with a MRI-compatible fiberoptic pulse-oximeter (NONIN), a capnography by naso-pharyngeal canula (OHMEDA) an d a noninvasive blood pressure oscillometer (CRITICON). The monitors were l ocated outside the 0.5 Tesla area and were connected to the patient via ext ension tubing. Additionally there was a clinical observation by a present a naesthesiologist. Results In all children the investigation has been realized without any pro blem. Haemodynamics, ventilation and oxigenation have been in a normal rang e. Only 2 of the 186 sequences had to be repeated. After a mean time of inv estigation of 29 minutes (10 to 55) the emergence time until purposeful rea ction was 7,7 minutes (5 to 20) and until full orientation was 13.4 minutes (5 to 30). Conclusions This regime of sedation for children undergoing Magnetic Resona nce Imaging is safe and suitable independent of age: there is a good contro l of vital functions, a minimum of side effects and a fine recovery charact eristic with short times of emergence.