Murphy’s Law states, “If anything can go wrong, it will.” Although the true origin and originator of Murphy’s Law remains in dispute (see http://www.murphys-laws.com/murphy/murphy-true.html), we posit that Murphy must have been an anesthesiologist.
Consider what we do, everyday, for every case. Typically, with little time, we see a surgical posting (that is often preceded by the word “possible”); review the patient’s chart to identify underlying medical conditions that might affect our anesthetic plan; sometimes speak with surgical personnel (although not always the surgeon) about the planned and possible procedures; evaluate the patient; prepare drugs we are sure to need, might need, or hope we will not need; and arrange equipment that will be needed, might be needed, or hopefully will not be needed. We obtain IV access and place a large-bore IV catheter in cases with any chance of significant blood loss. It is a complex routine, which we perform nearly flawlessly because we have integrated it into our daily habits.
As we have been able to deliver anesthesia services to sicker patients undergoing increasingly complex procedures, our surgical colleagues work diligently to push the envelope in the hopes of improving more patients’ lives. They bring new procedures and more complicated equipment to the operating room, often without a discussion with us, their anesthesiologist colleagues, as to the implication(s). Examples over the past 2 decades include the introduction of laparoscopic and robotic surgery, advanced radiofrequency (RF) surgical tools, and somatosensory-evoked potential monitoring, all of which affect the execution of our anesthetic plans. With our assistance, equipment is now also routinely implanted into patients using special procedures, including a myriad of electronic stimulators (deep brain stimulation, spinal cord stimulation, diaphragm stimulation, bladder stimulation, cochlear stimulation), ventricular assist devices, intraaortic balloon pumps, and, of course, implanted cardioverter–defibrillators (ICDs).
Which now brings us to a known corollary of Murphy’s Law, “Every new solution breeds new problems.” Fortunately, anesthesiologists have learned to adjust techniques, drugs, and equipment to mitigate the issues that arise in the operating room, whether expected and known or arising as complete surprises. In most cases, our adaptability does more than improve patient outcomes. It provides material for investigation that can in turn improve patient outcomes. It provides material for publication and therefore career advancement for those of us in the academic world. These situations provide material for educational presentations and therefore the opportunity to travel and establish new professional relationships across countries and cultures.
In this issue of A & A Case Reports, Plakke et al.1 describe a new solution to an old problem that has created a new problem. As they report, technology involving RF identification (new solution) of retained surgical equipment (old problem) likely has improved surgical outcomes by decreasing the possibility of operative material accidentally remaining inside a patient after surgery. This technology has been approved by the U.S. Food and Drug Administration (FDA), and many centers use it today.
However, unbeknownst to many personnel who use this technology in the operating room, this technology has the potential to create untoward events, especially in patients who depend on life-sustaining electronic devices. This behavior is not well characterized or described, is likely intermittent and unpredictable, and is clearly not well known. Even with the privately held information from RF Surgical Systems, the manufacturer of the equipment described in this case report (see references 10 and 11 in the article by Plakke et al.) as well as other reports,2,3 operating room personnel are not experts when electromagnetic interference (EMI) arises. Additional technical information from RF Surgical Systems does not appear to be readily available on their web site, and it is unclear whether they offer 24/7/365 technical support.
In the case of Plakke et al., EMI caused by RF scanning apparently led to oversensing on the ventricular lead of a temporary pacing system, which caused underpacing of the patient’s heart. Because the patient was pacing-dependent at that time, this underpacing resulted in asystole. This event further suggests that ventricular oversensing might also take place in a patient with an ICD, which could lead to inappropriate high-voltage therapy (i.e., a shock). Also, ventricular oversensing in a patient with an intraaortic balloon pump might compromise its function. Whether ICDs, balloon pumps, or any other implanted electronic equipment are mentioned in the privately held information from the RF equipment manufacturer cannot be determined because the information is not public. Also not clear is whether atrial oversensing could occur, which, in the presence of dual chamber pacing, would lead to ventricular pacing at the upper tracking rate (the programmed upper tracking rate was not specified in the case report but this pacemaker’s default value is 110 bpm).4 In addition, just how operating room personnel might acutely reprogram a permanently implanted pacemaker, ICD, or other important implanted electronic device remains to be seen. Because few anesthesiologists have been trained in perioperative pacing, cardiology services are busy and unlikely to interrupt their clinic or catheterization laboratory activities to enter the operating room to mitigate the risk of complications from an RF scan, and very few operative centers actually possess pacemaker and ICD programmers. Furthermore and of paramount importance, for the pacing-dependent patient with an ICD, asynchronous pacing can be accomplished only with reprogramming.
An interesting twist to this case is the adverse event report of this issue contained in the U.S. FDA database (http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/detail.cfm?mdrfoi__id=3208810). The report states that the RF equipment “…was not used in accordance with the device’s directions for use (dfu). Specifically, the temporary cardiac pacersa were not set to the correct mode by the physician (as directed in the dfu) prior to use…” Furthermore, the FDA report states “…hospital management reported that they had sponsored training on the…device and that the majority of the hospital staff participated in this training but the physicians involved in these reported events did not attend the training.” It appears that only the anesthesiologist (as the reporting physician) was identified. There is no mention of the surgeons or other operating room personnel.
Several important caveats can be gleaned from this event and subsequent reports: First, although this device had nothing to do with the provision of anesthesia per se and was not operated by the anesthesiologists, we read the FDA filing as having assigned responsibility for this event to the anesthesiologists. Next, according to the case report, the hospital policy for RF scanning in cases involving temporary pacemakers does not designate special handling before initiation of the RF scanning (such as a time-out). With no policy for initiating a scan, it appears the scan could be initiated without the previous knowledge of the anesthesiologist, precluding pacemaker reprogramming. Furthermore, the reprogramming policy might not allow consideration for the possibility of R-on-T pacing with possible resultant ventricular tachycardia or fibrillation, for which these patients appear especially sensitive.5 Finally, and perhaps most importantly, the adverse event report on the FDA web site suggests that personnel involved in this patient’s care had not participated in RF training, implying that training sign-ins might be easily discoverable documents and become a part of a tort proceeding arising out of patient injury.
In summary, this case report serves to educate all perioperative clinicians about new EMI dangers entering the operating room and other areas of the hospital with special attention required to patients with implanted electronics (e.g., could any new technology induce currents on deep brain or spinal cord stimulator leads and cause neural tissue injury?). These dangers exist in both temporary and likely permanently implanted electronic devices. In fact, anesthesiologists would be wise to consider every RF-emitting device as a possible threat to any implanted electronic device, including infusion pumps, mechanical ventilators, intraaortic balloon pumps, and monitors.6
Second, it alerts all perioperative personnel that extensive education (and perhaps policy) will be needed as new technologies enter the hospital. This is particularly true in critical care areas such as the operating room. In their response, the company states that “174 clinicians” were trained in the use of this equipment.7 However, given the size of the institution (approximately 100 anesthesiologists, 200 surgeons, 39 fellows, 56 residents, 118 certified registered nurse anesthetists, 35 anesthesia technicians, and 150 circulating nurses and scrub technicians), this number likely represents only approximately 25% of the people who arguably should have received this training. What about staff turnover as well as the yearly introduction of new residents and fellows?
Third, we believe that operators of any technology with potential to interfere with implanted electronics should be required to announce its intended operation to ensure appropriate preparation. We remain surprised that ventricular oversensing from RF scanning wands has not been reported, and we wonder why the FDA did not identify special populations at risk given the report from Seidman et al.2 (whose publication address lists the FDA).
Fourth, another issue not explored, but of potential concern, is whether a person with a permanently implanted pacemaker or defibrillator should avoid handling the wand. To our knowledge, there are no data regarding this issue. In the absence of a warning, an operator dressed in sterile garb might place the wand against his or her chest to maintain sterility. Although we would expect that the potential for EMI drops off rather quickly as distance increases from the wand, we do not see any cautionary statements from the company regarding the medical condition of the operator. The report by Seidman et al.2 states that RF scanning caused interference in vitro with some pacemakers and defibrillators at distances up to 60 cm.
This case report truly serves as the “canary in the coal mine” with respect to developing RF technology, whether in the operating room or elsewhere. We believe that all RF-emitting devices, especially those used in the medical environment, should carry a prominently displayed warning label that use on or by humans with any sort of implanted stimulator (to include the words pacemaker and defibrillator) must be limited and must follow requirements stated in the manufacturer’s directions for use.
We call on the FDA to visit the labeling requirements for these devices, and we suggest that a labeling requirement for these devices rises to the occasion of a boxed warning statement, often referred to as a “black box” warning. There should also be symbolic representation and accompanying text warning of the potential risk to patients and operators (e.g., Fig. 1) unless objective evidence suggests that the theoretical risks do not occur in practice. To do any less, we believe, puts patients, medical personnel, and perhaps nonmedical citizens at risk.
Finally, this case report also reminds us of the unstated but ubiquitous Murphy’s Law of the operating room: If something goes wrong, blame anesthesia.
a The event reports that pacing inhibition occurred in 2 different patients.
1. Plakke MJ, Maisonave Y, Daley SM. Radiofrequency scanning for retained surgical items can cause electromagnetic interference and pacing inhibition if an asynchronous pacing mode is not applied. A&A Case Rep. 2016;6:143–5
2. Seidman SJ, Brockman R, Lewis BM, Guag J, Shein MJ, Clement WJ, Kippola J, Digby D, Barber C, Huntwork D. In vitro
tests reveal sample radiofrequency identification readers inducing clinically significant electromagnetic interference to implantable pacemakers and implantable cardioverter–defibrillators. Heart Rhythm. 2010;7:99–107
3. Seidman SJ, Kainz W, Casamento J, Witters D. Electromagnetic compatibility testing of implantable neurostimulators exposed to metal detectors. Open Biomed Eng J. 2010;4:63–70
5. Schulman PM, Stecker EC, Rozner MA. R-on-T and cardiac arrest from dual-chamber pacing without an atrial lead. Heart Rhythm. 2012;9:970–3
6. van der Togt R, van Lieshout EJ, Hensbroek R, Beinat E, Binnekade JM, Bakker PJ. Electromagnetic interference from radio frequency identification inducing potentially hazardous incidents in critical care medical equipment. JAMA. 2008;299:2884–90
7. Kane T. Editorial Comment: manufacturer’s response. A&A Case Rep. 2016;6:142