In our January 2017 What's New in the Patient Safety World column “” we cited a recent presentation at the 2016 RSNA meeting that showed the use of MRI scanning in pediatric patients has been increasing in the emergency department at a major New York City hospital (Hulkower 2016). We suspect that is a trend we’d see at many hospitals across the country. The reasons for more MRI scans are mostly due to the increased availability of MRI, the campaigns to reduce the use of ionizing radiation, particularly in children, such as the Imaging Gently® campaign, and the fact that some diagnoses are more readily found on MRI than on CT scan. In the Hulkower study the increase in MRI was primarily driven by neurological imaging and there was a corresponding decrease in the use of CT scanning.
Along with that trend we’d be concerned we may see more patient safety issues arising. We’ve actually done numerous columns on patient safety related to MRI scanning (see the full list at the end of today’s column) and pediatric patients have special concerns that render them more vulnerable to safety incidents during MRI.
In our February 19, 2008 Patient Safety Tip of the Week “MRI Safety” we noted that not even a month after the first published paper on projectile cylinder accidents in MRI units (Chaljub 2001) there was a fatality related to an MR-related projectile accident. A 6 y.o. boy developed respiratory distress while undergoing an MRI. There was a problem with the oxygen source in the MRI suite. Both MR technologists briefly left the MR suite to try to resolve the issue but in the interim a nurse responding to anesthesiologist’s calls for help found an oxygen cylinder in the control room and brought it into the MR room. Unfortunately, it was steel cylinder and the MR pulled the cylinder free, thrusting it into the bore of the MR machine and causing a fatal head injury to the boy. Root cause analysis of the latter event by Tobias Gilk and Robert Latino (Gilk 2011, video ) showed the typical cascade of events and errors that collectively led to the unfortunate outcome. Many of the same conditions and events occurred in the cases assembled by Chaljub et al. had reported on 5 projectile cylinder accidents at 2 academic medical centers. Cases involved ferromagnetic cylinders of oxygen or nitrous oxide inadvertently being introduced into the MR rooms and turned into projectiles by the magnetic forces of the MR machine, resulting in patient injury or damage to the MR unit or both. They also sent out questionnaires to multiple academic MR units and found slightly more than 50% of those who responded had experienced similar projectile incidents. Objects involved included vacuum cleaners, mop buckets, tools boxes, ventilators, defibrillators, wheelchairs, IV poles, etc. Failure to adhere to MR safety policies and human error were cited as the most common reasons for the accidents.
Another recent presentation at the 2016 RSNA meeting showed that the prevalence of safety reports in MRI performed in children is increased relative to previously published data on adults (Jaimes Cobos 2016). They found the rate of such reports was 0.53%, compared to a 0.35% rate of incident reporting for adults at the same hospital (Mansouri 2016). Jaimes Cobos and colleagues found that younger children had higher rates of safety reports: newborns (1.1%), infants (1.1%), and young children (0.9%). Those rates were significantly higher than those in older children. The odds ratio of younger children (<6 yrs) having a safety report relative to older children (>6yr) was 2.2. As in adults, the rates were highest for inpatients, followed by ER patients, then outpatients. The majority of events caused no harm or only minor harm. There were no deaths and only 3% of the incidents reported involved major harm. Children below the age of 6 years, inpatients, and use of sedation or general anesthesia were all factors associated with higher safety report rates. The most common causes of safety reports were service coordination and adverse drug reactions. You’ll recall from our numerous columns on patient safety in the radiology suite (full list below) that the majority of patient safety issues seen in the radiology suite have little to do with the imaging study or radiology itself. Rather it is the confluence of vulnerable patients being temporarily in an environment where communication and coordination issues can be problematic.
In our Patient Safety Tips of the Week for March 17, 2009 “More on MRI Safety” and October 25, 2011 “Renewed Focus on MRI Safety” we discussed some of the care coordination issues that arise for any patient undergoing MRI. We discussed the American Society of Anesthesiologists Practice Advisory on Anesthetic Care for Magnetic Resonance Imaging, which has now been updated in 2015 (ASA 2015). It states that the anesthesiologist needs to develop a plan for implementing anesthesia care before each individual case. Such a plan should be done in collaboration with other personnel who will be involved in the care of the patient, including the MRI technician, radiologist, radiology nurse, other clinical personnel accompanying the patient and even the facility biomedical engineer. In addition to the anesthetic plan, preparation includes a plan for optimal positioning of equipment and personnel in the MRI suite during the procedure. We refer you to that guideline for details. The anesthesiologist should also prepare a plan for rapidly summoning additional personnel in the event of an emergency.
We suggested a few additions to this otherwise excellent ASA practice advisory. First is the importance of determining up front whether the MRI is truly indicated, whether the potential benefits of performing the MRI outweigh the potential risks, and whether alternative safer imaging modalities might suffice. In many of the incidents we’ve seen occurring in ICU patients transported to the MRI suite or radiology suite, we’ve been surprised at how often the scan being done was really of marginal value.
Second is the need for a huddle/timeout before the procedure is performed. We should approach doing MRI on these critically ill patients in the same manner in which we approach patients going to the OR. A “huddle” or whatever else you’d like to call a pre-procedure briefing is very important in such cases. Not only do you need to know you have all the equipment needed, but you also need to know everyone’s role and have contingency plans for emergencies. This is where you ensure all parties know what to do if there is a fire or if there is a cardiopulmonary arrest or a “quench”. You discuss what location you will need to move the patient to in such events. You discuss the availability and location of equipment and medications you may need. You discuss the line of sight required and where the monitoring equipment will be deployed. You may need to discuss also how you will communicate (with both staff and patient) given the high noise levels associated with MRI scanning. You should probably even discuss the potential impact of the lighting levels in the various zones (and fact that you may not be able to wear your ferromagnetic glasses in Zones III and IV).
Third, really related to the above, is use of a checklist. To remember all the needs for the procedure (which vary be individual patient) and the contingencies you have to plan for is really too much to expect for any individual or group of individuals. That’s where the simple checklist comes in: it helps you to remember details you might otherwise overlook.
Fourth, you need to practice. We wonder how many MRI facilities, particularly hospital-based ones, actually simulate an emergency during MRI scanning.
Use of sedation is probably the most serious issue in pediatric MRI safety. Our August 2016 What's New in the Patient Safety World column “” discussed the recently updated American Academy of Pediatrics (AAP)/American Academy of Pediatric Dentistry (AAPD) “Guideline for Monitoring and Management of Pediatric Patients During and After Sedation for Diagnostic and Therapeutic Procedures” (Coté 2016). We refer you to our prior column and the updated guideline itself for all the details needed in performing safe sedation in pediatric patients for any procedure. But the guideline has an excellent section on sedation in the MRI suite, which is a very restricted environment and has needs for special equipment and monitoring techniques as we have discussed in our numerous columns on patient safety issues in the radiology and MRI suites. It notes that MRI-compatible pulse oximeters and capnographs capable of continuous function during scanning should be used in any sedated or restrained pediatric patient. Appropriate precautions must be taken to avoid thermal injuries. For example, the practitioner is cautioned to avoid coiling of all wires (oximeter, ECG) and to place the oximeter probe as far from the magnetic coil as possible to diminish the possibility of injury. It notes that ECG monitoring during MRI has been associated with thermal injury and that special MRI-compatible ECG pads are essential to allow safe monitoring. If sedation is achieved by using an infusion pump, then either an MRI-compatible pump is required or the pump must be situated outside of the room with long infusion tubing so as to maintain infusion accuracy. All equipment must be MRI compatible, including items such as laryngoscope blades and handles, oxygen tanks, and any ancillary equipment. In addition, all individuals, including parents, must be screened for ferromagnetic materials, phones, pagers, pens, credit cards, watches, surgical implants, pacemakers, etc, before entry into the MRI suite.
In our August 2010 What's New in the Patient Safety World column “Sedation Costs for Pediatric MRI” we discussed a study (Vanderby 2010) that addressed the financial impact of sedation for MRI scanning in pediatrics. They analyzed the workflow, personnel, and costs involved in MRI scanning of children at Hospital for Sick Children in Toronto, Ontario. They found that the average time spent in the MRI suite was 2 hours and 21 minutes for children scanned awake, 3 hours 38 minutes for those sedated, and 4 hours 7 minutes for those anesthetized. Corresponding average costs (in Canadian dollars) were $54.68, $177.27, and $522.73 respectively. The Toronto group used their analysis to significantly redesign workflow and scheduling. This article has a good discussion about those workflow and personnel issues and has some good lessons learned that you may apply in your organization. To their recommendations we would again add that strong consideration needs to be given to the appropriateness of the MRI scan, in light of the patient safety and cost issues involved.
Note that the Hulkower study noted above (Hulkower 2016) also had some workflow implications. They found the highest pediatric MRI volume was during the evening and early nighttime hours with peak volume occurring during the 10 PM hour when 8.2% of MRI exams were performed. That suggested the need for deployment of additional resources at certain times and need for availability of radiologists, particularly those with expertise in neurological MRI, to read the MRI scans.
We discussed another issue primarily related to pediatric patients in our August 2012 What's New in the Patient Safety World column “Newest MRI Hazard: Ingested Magnets”: harm due to MRI in patients who have ingested magnets. Small children frequently ingest non-food items and may not be able to verbally tell you they did so. A cited paper () described a case of a 5 y.o. boy who had ingested magnets and had an MRI that led to bowel perforation. The authors reviewed the literature and came up with a recommended tool to screen for magnets before MRI is performed. The authors note that most cases of ingested magnets occur in young children and most often boys and are often, in fact typically, not witnessed. Most are passed in the stool without incident and less than 10% require intervention (only 1% requiring surgery). However, swallowing multiple magnets may be more troublesome since the magnets adhere to each other, increasing the likelihood they might obstruct the bowel. In their index case, the authors note the patient actually presented to an ED with complaints of neck pain. Initial workup focused on the cervical spine and included a normal CT scan of the neck and normal lumbar puncture. A decision to do an MRI of the brain and cervical spine was then done under moderate sedation and was also negative. The following day his neck pain was better but he now had severe abdominal pain and would not eat. Abdominal X-rays showed air in the peritoneal cavity and 11 small round metallic objects in the left upper quadrant. At surgery, four full-thickness small intestinal perforations were found and 11 small spherical magnets were removed from the peritoneal cavity. The magnets were most likely from a magnetic game the child had been playing near. He had an uneventful recovery.
The hospital changed their MRI screening protocol. While they still do a written and verbal questionnaire of the children and parents for presence of metallic objects, they now also have all children change into a hospital gown and undergo screening using a hand-held ferromagnetic detection scanner.
An FDA safety warning just released (FDA 2017a) about MRI and implantable infusion pumps could apply to children as well as adults. FDA has received reports, including some with serious patient harm or death, of problems with such pumps following MRI. They have noted issues such as medication dosing inaccuracies (e.g., over-infusion or under-infusion, unintended bolus) and other mechanical problems with the pump (e.g., motor stall, pump not restarting after an MRI exam). FDA recommends that the “implant card” (which is usually issued at the time of pump implantation) for the specific implantable infusion pump accompany the patient to the MRI site so that the MRI technologist and team can identify the specific pump model to locate the specific MRI safety information for that pump. It even recommends patients consider obtaining a medical alert bracelet or necklace to notify medical professionals that they have an implantable pump. Even when the specified conditions of MR Conditional use have been followed, the implantable pump may need to be checked and/or reprogrammed by the healthcare team responsible for the pump. And don’t forget that only implantable infusion pumps labeled as “MR Conditional” may be safely scanned, and only under the specific conditions of safe use. A companion document (FDA 2017b) provides recommendations for patients, MRI technologists, radiologists, healthcare professionals who implant and those who manage the infusion pumps, and those who prescribe/order MRI exams.
Lastly, a coalition of societies and organizations dealing with MRI has proposed a delineation of responsibilities for the management of MRI facilities (Calamante 2016). Though it does not specifically note issues related to pediatric patients, this document does a nice job of identifying the roles of various people in ensuring overall safety in an organization’s MRI activities and the types of safety activities that should be undertaken.
You’ll also find many valuable tips on MRI safety for both children and adults in our previous columns listed below.
Some of our prior columns on patient safety issues related to MRI:
Some of our prior columns on patient safety issues in the radiology suite:
Hulkower M, Taragin B, Davoudzadeh R, et al. Pediatric MRI in the Emergency Department Over Five Years: An Analysis of Usage and Trends. Program SSQ17-06. Radiological Society of North America 2016 Scientific Assembly and Annual Meeting, November 27 - December 2, 2016, Chicago IL
Imaging Gently® Campaign
Chaljub G, Kramer LA, Johnson RF, Johnson RF, Singh H, Crow WN. Projectile Cylinder Accidents Resulting from the Presence of Ferromagnetic Nitrous Oxide or Oxygen Tanks in the MR Suite. Am. J. Roentgenol 2001; 177: 27-30
Gilk T, Latino RJ. MRI Safety 10 Years Later. What can we learn from the accident that killed Michael Colombini? Patient Safety and Quality Healthcare 2011; online first Nov-Dec 2011
Latino RJ, Gilk T. Healthcare RCA - Michael Colombini MRI. Root Cause Analysis Movie: Colombini MRI Case: - 10 Years Later. Reliability Center, Inc. 2011
Jaimes Cobos C, Murcia D, Miguel K, et al. Identification of Quality Improvement Areas in Pediatric MRI from Analysis of Patient Safety Reports. Radiological Society of North America 2016 Scientific Assembly and Annual Meeting, November 27 - December 2, 2016, Chicago IL
Mansouri M, Aran S, Harvey HB, et al. Rates of safety incident reporting in MRI in a large academic medical center. Journal of Magnetic Resonance Imaging 2016. 43(4): 998-1007
ASA (American Society of Anesthesiologists). Practice Advisory on Anesthetic Care for Magnetic Resonance Imaging: An Updated Report by the American Society of Anesthesiologists Task Force on Anesthetic Care for Magnetic Resonance Imaging. Anesthesiology 2015; 122(3): 495-520
Coté CJ, Wilson S, American Academy of Pediatrics, American Academy of Pediatric Dentistry. Guidelines for Monitoring and Management of Pediatric Patients Before, During, and After Sedation for Diagnostic and Therapeutic Procedures: Update 2016. Pediatrics 2016; 138(1): e2016121
Vanderby SA, Babyn PS, Carter MW, et al. Effect of Anesthesia and Sedation on Pediatric MR Imaging Patient Flow. Radiology 2010; 256(1): 229-237
Bailey JR, Eisner EA, Edmonds EW. Unwitnessed magnet ingestion in a 5 year-old boy leading to bowel perforation after magnetic resonance imaging: case report of a rare but potentially detrimental complication. Patient Safety in Surgery 2012; 6: 16 (19 July 2012)
FDA (US Food & Drug Administration). Implantable Infusion Pumps in the Magnetic Resonance (MR) Environment: FDA Safety Communication - Important Safety Precautions. FDA 2017; January 11, 2017
FDA (US Food & Drug Administration). Safety Concerns with Implantable Infusion Pumps in the Magnetic Resonance (MR) Environment: FDA Safety Communication. FDA 2017; January 11, 2017
Calamante F, Ittermann B, Kanal E, The Inter-Society Working Group on MR Safety and Norris D. Recommended responsibilities for management of MR safety. JMRI 2016; Early View 3 Jun 2016