By William Hyman, ScD
William Hyman
On February 18, 2015, the FDA posted a notification on its website of a Class I recall of almost 13,000 General Electric MRI systems covering 25 different models in the Sigma and Discovery brands. The FDA notification includes what appears to be all 12,968 serial numbers, which may be a forerunner of what will be seen when every device has an individual number under FDA’s forthcoming unique device identification (UDI) system.
GE had previously acted on this matter with an Urgent Medical Device Correction letter dated January 8, 2015. Note that the title of this letter does not include the word recall. A February 4, 2015, news release at GE’s website calls the action a Voluntary Field Corrective Action, which may sound far more benign than a Class I recall, and differs from GE’s own letter.
The problem as reported by the FDA is “the MRU may not be connected to the magnet.” As the notification explains, “In emergency situations, a disconnected MRU could delay removal of a ferrous object from the magnet, potentially resulting in life-threatening injuries. The MRU must be connected to the magnet at all times.” The FDA lists the Determined Cause of the recall as “Training: Employee Error.” Three things can be deduced from this categorization. First, the implication is that the necessary connection is a hospital-based employee issue. Second, one can infer that the machine does not communicate to the user that a key connection has not been made. Third, it functions in nonemergency situations (normal use) without the connection.
And thus we have a blame-the-user rather than a blame-the-design attitude. One must wonder if the FDA personnel who apparently bought into this reasoning are aware of the agency’s efforts in human factors that have taken place over a good number of years. AAMI has also devoted a good deal of attention to human factors, in part in collaboration with the FDA. One must also wonder what GE thinks about human factors, and whether they apply it in design, or just ignore it when faced with a massive problem that allows for blaming a user. In its human factors summary, the FDA includes several items that appear to be directly applicable here. These are:
- Safer connections between device components and accessories;
- Better user understanding of the device’s status and operation;
- Reduced user reliance on user manuals;
- Reduced need for user training and retraining; and
- Reduced risk of use error.
These factors are all related to reduced risk of adverse events, and reduced risk of product recalls.
Part of the GE notification was to instruct users to “…perform a short test that confirms if the Magnet Rundown Unit is functioning properly and has not been disabled.” The notification explains that, “This test is an action that operator manuals currently advise users to do on a regular basis.” What level of “user” is meant here is not indicated. The reference to the operator manuals suggests that this is a prescribed maintenance procedure. It also suggests that users are actually expected to read the operators manual. In this regard, I was surprised a while ago to be told by clinical personnel that they don’t read operators manuals, they have never seen the operators manual, and that they don’t think they should be expected to read the operators manuals. I have addressed this read-the-manual issue elsewhere.
From the scanty information available about this recall, I could not determine whether connecting the MRU is a one-time event that, presumably, should take place at installation and perhaps after service of some level. The need for a routine maintenance requirement may imply that the connection could have been made earlier but then was disconnected.
My proposition is that if it is essential that two components of a device be properly connected, especially when there is electronic communication available, then the system should not operate unless they are in fact properly connected. Is this too radical? Please share your responses in the comments field below.
William A Hyman, ScD, is professor emeritus, Biomedical Engineering, at Texas A&M University, College Station, Tex, and adjunct professor of Biomedical Engineering at The Cooper Union, New York.
One important fact is missing in your discussion here and that is the PM procedure for the system require the GE engineer or qualified In-house engineer to perform the test of this circuit every PM on a quarterly basis. While you can point finger of blame at operators and techs the true responsibility still belongs to following the service and proper maintenance procedures. It would make sense with this now becoming an issue to set up some sort of circuitry that would constantly monitor the connection and alarm if the circuit is broken.
I don’t know what the PM instruction actually says, or if people actually do it. Even manufacturer service has been known in general to not necessarily follow listed procedures. We do know however that in most cases PM does not actually prevent most things, it just tells you current status. However it is that the units can get disconnected could occur between PMs. In addition all instances of use error can be answered with blaming the user. But human factors asks us to predict and prevent error.
I have to agree. If this connection is so critical to warrant a recall notice, you would think there would be, at the very least, a warning message on the operator’s console.
Both of the notices issued by GEMS concerning the MRU are (just shake your head side to side).
First, how could any connection between the MRU and the Magnet get disconnected in the first place? Certainly not by the “user”.
Second, I know of no other manufacturer that has the Rt (insert user) check the function of this important safety feature to insure function.
Third, it is apparent that the sticker over the plexi cover of the MAGNET NOT button is not adequate to override the stupidity factor. If this is a problem as stated in the initial letter then GEMS should have inspected each site to ensure that the connnection is intact and function valid. The MRU should be tested at least yearly during a PMI by GEMS or other qualified Service Engineer.
We finally get to the fact that GEMS did not incorporate a safety flag into the system software and hardware if after servicing the magnet the Quench control cable was left disconnected. Where has common sense gone?
If the PM interval is annual (see below for assertion it is quarterly) that leaves a full year for the MRU to get disconnected, however that occurs, without anyone noticing.
This is a very important safety issue. In my opinion there should be a fail safe system that does not allow the magnet to be engaged and provides a warning to check the MRU if it is not connected. And of course the MRU function should be tested during the PM procedure. Maybe there should also be a ferrous object sensing and warning system at the entrance of the room.