Atelectasis in children undergoing either propofol infusion or positive pressure ventilation anesthesia for magnetic resonance imaging

BACKGROUND: Atelectasis because of anesthesia is a recognized problem but may be affected by the anesthetic technique. We compared magnetic resonance images of atelectasis in children undergoing two types of anesthesia. METHODS: Children requiring anesthesia for magnetic resonance imaging (MRI) had additional lung imaging sequences at the beginning and the end of anesthesia. Children had either i.v. propofol infusion (PI) without an artificial airway (n = 26) or positive pressure ventilation (PPV) via a tracheal tube (n = 20); the technique was chosen for clinical reasons. The extent of atelectasis was scored by two independent radiologists. RESULTS: The median ages (range) for PI and PPV groups were 45 months (1-77 months) and 18 months (2-74 months), respectively. The proportion of children with atelectasis was different in the first lung scan (42% vs 80%), but in the second scan atelectasis was seen frequently in both groups (82% vs 94%) with a greater extent in the PPV group. The atelectasis score was higher in young children, but all children had normal oxygen requirements and saturations. CONCLUSIONS: Many factors may influence the development of atelectasis but this study found less extensive atelectasis with PI than PPV. PI allows for sufficient motionlessness, required for high diagnostic image quality in pediatric MRI.