Letters to the Editor
Like many anesthesia practices, we are called on to provide sedation/anesthesia to patients undergoing magnetic resonance imaging (MRI). In many cases, this is accomplished with IV sedation.
Recently, we had instituted a change in procedure for the administration of propofol. Previously, we had used an infusion pump outside the scanner room, but the infusion tubing was often trapped in the closed door. We recently changed this to use of an infusion pump in the scanner room itself, given several reports of acceptable results of infusion pump function and image quality (1,2), as well as the personal experience of some of the anesthesiologists in our practice.
This change in policy was discussed with the entire practice. Shortly thereafter, we were called on to provide anesthesia for a 49-yr-old woman who was to undergo pallidotomy for severe dystonia. A MRI was to be obtained before surgery. Given the patient’s severe dystonia and her inability to lie still for imaging, a propofol infusion was begun. The patient became adequately sedated, was hemodynamically stable, and was placed into the scanner.
As the patient was being advanced into the scanner, the infusion pump “flew” into the scanner and struck the patient, causing a 2-cm laceration to the patient’s chin. Apparently, the pump had been left on the moveable part of the gurney, and when the pump came within approximately two feet of the magnet, it was drawn into the scanner. We had intended to keep the infusion pump at least 2.0–2.5 m from the scanner.
Whereas many institutions are using infusion pumps in the MRI setting, it is important to remember that these pumps are not “MRI compatible.” Great care needs to be exercised to be certain that all users are aware of the potential dangers, so that we can keep our patients as safe as possible.
Theodore M. Wynnychenko
MD Joseph W. Szokol
MD Glenn S. Murphy, MD
1. Pope KS. An infusion pump that works in MRI [letter]. Anesth Analg 1993; 77:645.
2. Kovac A, Swanson B, Elliott C, Wetzel L. Effect of distance and infusion rate on operation of Medfusion 2010 infusion pump during magnetic resonance imaging [abstract]. Anesth Analg 1999; 88:S186.