Delivery of Inhaled Nitric Oxide During MRI to Ventilated Neonates and Infants.

BACKGROUND

Many pediatric and neonatal ICU patients receive nitric oxide (NO), with some also requiring magnetic resonance imaging (MRI) scans. MRI-compatible NO delivery devices are not always available. We describe and bench test a method of delivering NO during MRI using standard equipment in which a NO delivery device was positioned in the MRI control room with the NO blender component connected to oxygen and set to 80 ppm and delivering flow via 12 m of tubing to a MRI-compatible ventilator, set up inside the MRI scanner magnet room.

METHODS

For our bench test, the ventilator was set up normally and connected to an infant test lung to simulate several patients of differing weight (ie, 4 kg, 10 kg, 20 kg). The NO blender delivered flows of 2-10 L/min to the ventilator to achieve a range of NO and oxygen concentrations monitored via extended tubing. The measured values were compared to calculated values.

RESULTS

A range of NO concentrations (12-41 ppm) and values (0.67-0.97) were achieved during the bench testing. The additional flow increased delivered peak inspiratory pressure and PEEP by 1-5 cm HO. Calculated values were within acceptable ranges and were used to create a lookup table.

CONCLUSIONS

In clinical use, this system can safely generate a range of NO flows of 15-42 ppm with an accompanying range of 0.34-0.98.