May 24, 2006
- Medical Telemetry and Wireless Connectivity, an FDA Perspective by Nancy Pressly
- Medical Telemetry Then and Now, Richard Diefes, Associate Director, Health Devices Group, ECRI
- Wireless Medical Telemetry Systems: Implementation in the Real World, Rick Hampton, Wireless Communications Manager, Partners HealthCare Systems
- *Hospitals Face Higher Telemetry EMI Risks in 2006, Eileen Putnam
- *Lessons Learned From Interference to Wireless Medical Telemetry Service Systems, Rick Hampton, Wireless Communications Manager, Partners HealthCare Systems
*Reprinted with permission from Biomedical Instrumentation & Technology (BI&T), a peer-reviewed journal published by the Association for the Advancement of Medical Instrumentation (AAMI). Visit www.aami.org to learn more about AAMI. To view BI&T’s current issue, go to www.aami-bit.org
Current Issues in Medical Telemetry and Wireless Connectivity.
Moderator: Terrie Reed
May 24, 2006
1:00 pm ET
Coordinator: Welcome to our conference of Current Issues in Medical Telemetry and Wireless Connectivity.
During today’s presentation, there will be multiple question and answer sessions. At those times, to ask questions or make comments, simply press star-1 on your telephone. After pressing star-1, you’ll be prompted to record your name for pronunciation only. Until then, all lines will be in a listen-only fashion.
At the request of the company today, this conference call is being recorded for transcription purposes.
Now, I’ll introduce your host for the call today, Ms Terrie Reed.
Ma’am you may begin.
Terrie Reed: Thank you, operator.
And I want to thank all of you who are participating and taking the time to participate in this call. I’d also like to thank (Chuck McCullough) who is a SSS staff member and coordinated the speakers and the logistics of the call, as well as (Quynh Nguyen) who works here at FDA as a MedSun team member and assisted in the planning and administration of the call.
The structure of the call today, there will be 15 to 20 minutes for each speaker. Each speaker will be referring to handouts that you should have gotten from the registration Web site. Both the agenda and PowerPoint are available at http://medsunaudioconference.s-3.net and that’s the same place you would have registered for the call.
If you for some reason you don’t have access to the Internet, you can call our contractor at 800-859-9821 and they can email them to you.
I want to make sure and reiterate that we are transcribing the call for future reference on the Web site, so you need to know that the discussion is not confidential.
The purpose of the call today: FDA has been working with the FCC, manufacturers, and healthcare facilities in the area of telemetry and wireless technology for several years. During this time, communications technology has become more sophisticated and the competition for frequencies and spectrum space for transmitting this information has steadily increased.
There is a general awareness of the potential for interference between systems. But there is uncertainty about the extent of the interference and a desire to develop strategies for minimizing this interference to avoid harm to patients.
This conference is designed to provide a historical perspective and overview of medical telemetry systems, increase your knowledge of potential interference between medical telemetry systems and other wireless technologies, increase your knowledge of recent FCC and FDA actions and implications for your facility, and provide actions you can take to reduce interference issues in your facility.
We’re also interested in hearing how MedSun participants have dealt with this issue. If you would rather not share that on this call, we do offer you the device safety exchange where you can enter your lessons learned or success stories or questions about the issues raised here.
I also want to tell you that we will have a mantra in today’s call and that will be to encourage you to report these kinds of issues to FDA when a medical telemetry or other wireless technology issue with a medical device is suspected.
When you registered for the call, you had an option to answer questions about your use of medical telemetry. Fifty-five people responded to those questions. However, there were a total of 73 answers to these questions which indicates to me that several of you are using more than one type of telemetry in your facility.
The results of this survey will be discussed in more detail during the presentation, but as an introduction, to understand the types of telemetry used by those on the call, 25% of you said that you were still using VHF/UHF for telemetry, 8% that you were using PLMR, 56% were using WMTS, and 11% were using the ISM band. And all of those acronyms will be explained in the presentation.
Finally, as a disclaimer, we have to say that the opinions or assertions presented during this audio conference are the private views of the presenters and are not to be construed as conveying either an official endorsement or criticism by the US Food and Drug Administration.
We are fortunate today to have experts in this field who are willing to share their knowledge with us. One is from a healthcare facility, one from a nonprofit medical device safety consulting group, and we will end with the FDA perspective on this issue.
Now, if you pulled off an agenda prior to today, we had a last minute change on the agenda. We’ve decided to start with our ECRI speaker who will give an overview and to end with the FDA speaker.
And so, unlike in previous audio conferences where we waited to ask questions until the very end, we’ve decided today that after the first speaker, talks about an overview of telemetry that we’ll have just a brief period for those of you who may have clarifying questions, who may not understand some of the concepts and need to go over that a little bit. So that might be 5-10 minutes.
If for some reason you must leave early or you’re unable to get any of your questions answered either during that time or by the end of the call, please send an email to (Chuck McCullough), his email address is on the clinical engineering conference registration page.
Okay, now that that’s all out of the way, let me introduce our first speaker - his name is Richard Diefes and he’s Associate Director of the Health Devices Group at ECRI.
Rich has been with ECRI since 1995 and has conducted a number of projects on wireless technologies and monitoring systems. He has been the project lead for several comparative evaluations of physiologic monitoring systems which were published in ECRI’s Health Devices Journal. Mr. Diefes has also been the principal investigator on many problem reports submitted to ECRI involving monitoring devices and use of wireless technology.
In support of ECRI’s Accident and Forensic Investigation Group, he has served as the lead investigator in greater than a dozen cases and has provided expert testimony related to his forensic investigation work.
And as I’ve said, the title of this presentation is Overview of Medical Telemetry and it’s basic enough for those who are not intimately involved in this area. But if you do have questions, please write those down and we will have a brief period after his presentation for you to ask those questions.
Okay, go ahead, Rich.
Richard Diefes: All right.
Well, thank you very much, Terrie. I appreciate the opportunity to speak today. And to get things started, I’d like to focus on the evolution of medical telemetry over the past few years, giving some discussion on where we’ve come from and where we are currently with medical telemetry.
Moving on to Slide 2, I’d first like to start out by briefly discussing who ECRI is for those of you who may be unfamiliar with us.
ECRI is a nonprofit health research agency whose mission it is to promote the highest standards of safety, quality, and cost effectiveness in healthcare to benefit patient care through research, publishing, education, and consultation.
To this end, ECRI provides a number of different services that include technology decision making to help healthcare facilities plan and make the right decision for investing in technology for the future; supply chain support to provide guidance and recommendations for which products will best meet the needs of a healthcare facility; quality in patient safety to inform healthcare facilities about hazards and recalls, provide tools in risk management, and investigate problem reports; and finally, information analysis and delivery in support of clearinghouses such as the National Guideline Clearinghouse and the National Quality Measures Clearinghouse.
Let’s move on the graphic on Slide 3.
First of all, let’s start out by defining what we mean by medical telemetry.
We’re referring to the patients wearing telepacks or transmitters that are most typically used to monitor ECG, although monitoring of pulse oximetry as well is also becoming more common. These telepacks or transmitters wirelessly send data to an antenna network which in turn, sends the data to a central station monitor. The central station then displays the ECG waveforms of the patients on telemetry and issues alarms to inform staff about clinically significant events. In the traditional sense, each transmitter sends its data out on a different frequency so that the transmitters don’t interfere with each other.
Turning to Slide 4, if we go back a few years to the mid to late ‘90s telemetry packs were for the most part, only capable of providing ECG monitoring. In addition, the only type of transmission available for the telepack was narrow band transmission. And what this means is that each telepack was set to specific frequency or channel and each channel is spaced usually 25 or 50 kilohertz away from adjacent channels. This transmission was unidirectional, meaning that the signal is sent from a telepack to the central station, but there’s no way for the central station to communicate back to the telepack. As a result, if signal loss were to occur during transmission from the telepack to the central station, there was no way for the central station to communicate this back to the telepack and request that the telepack resend the lost data.
Back then there were two frequency bands that were available, VHF/UHF television and private land mobile radio.
If we move on to Slide 5, we could start out talking about the VHF/UHF TV telemetry band. These bands cover frequencies in the range 174 to 216 megahertz corresponding to TV channels 7 to 13. They also cover 470 to 608 megahertz corresponding to TV channels 14 to 36. And finally, 614 to 668 megahertz corresponding to TV channels 38 to 46.
Notice that I skipped over Channel 37. This channel has been reserved for use by radio astronomy so that no TV broadcast is permitted on this channel. I will bring up Channel 37 again as it relates to telemetry later on in my talk.
The way that medical telemetry works in these bands is that the telepacks are set to transmit on frequencies corresponding to unused TV channels.
Let’s take a look at this on the next slide.
In this example, TV Channel 8, the green box, and TV Channel 10, the red box, represent two broadcasting TV channels. To avoid these two broadcasting TV channels, medical telemetry is set up to operate on the frequencies corresponding to the unused TV Channel 9. Each yellow bar represents transmission from a single telepack. Keep in mind that the actual TV channels in use will vary with geographic location.
FCC provides an online tool that you can use to help determine all the TV broadcasts in your area and I’ll get back to this tool in a few slides.
So if telemetry is set up to avoid broadcasting TV channels then what’s the big deal? Why not just continue to keep avoiding TV channels that are being used? Well the answer is on Slide 7, digital television.
Digital TV is now filling in some of those unused TV channels, literally squeezing medical telemetry out of the picture.
To illustrate how digital television has impacted the use of telemetry let’s go back a few years to an incident that occurred in Dallas, Texas as described on the next slide.
Keeping with the design to use medical telemetry in unused TV channels both Baylor Medical Center and Dallas Methodist Hospital have set up telemetry to operate on frequencies within TV Channel 9. The systems were operating normally until late February 1998 when all of a sudden, signals from a number of telepacks were no longer being displayed at the central station; they just blanked out.
It was discovered that local TV station WFAA had just started broadcasting digital TV on Channel 9. Unfortunately, because there was no communication between the TV station and the hospitals, the fact that the hospitals’ medical telemetry and the TV broadcast were operating on the same frequencies wasn’t discovered until it was too late.
Fortunately however, this incident quickly got the attention of both the FCC and FDA and on March 25, 1998, FCC and FDA issued a joint statement to warn both the healthcare and television broadcast communities about the potential interference.
As we look at the graphic on Slide 9, we see that the hospital had chosen to set their telepacks to operate on frequencies in unused TV Channel 9 to avoid the TV broadcast on Channel 8. Unfortunately, they weren’t aware that the new digital TV broadcast was going to launch on Channel 9.
Turning to Slide 10, the question is what does this all mean for future use of medical telemetry in these TV bands? Bottom line is continued use of telemetry in these frequencies is possible.
Careful planning and establishing open lines of communication with local TV stations will allow healthcare facilities to define the risk of interference from TV broadcasts and plan accordingly.
The risk of interference can be fairly well-defined in this case because TV station broadcasts do not move around and they operate on well-defined frequencies. In addition, new digital TV broadcasts are well-documented and can be planned for prior to going live.
While continued operation of telemetry in the TV bands is possible, use of these frequencies for new telemetry systems is not an option since medical telemetry suppliers no longer produce new telemetry products operating in these bands.
As I mentioned back on Slide 6, the FCC provides a very useful tool that can be used to define the TV broadcasts in your area, the FCC TV Database Query. This query allows you to enter your location, city and state, and provides a list of TV broadcasts in your area. Additional links provide maps of broadcast coverage areas so that you can see where your facility is situated relative to a TV station’s broadcast coverage area.
Another FCC site to check out is the Low Power TV site.
Moving on to Slide 11, let’s turn to the second band that was available for medical telemetry use, the private land mobile radio band. This band covers frequencies from 450 to 470 megahertz. Note that TV does not broadcast on these frequencies. So digital TV doesn’t have a direct impact on telemetry in this band.
The way that medical telemetry works in the PLMR band is that medical telemetry operates in between PLMR channels. PLMR channels are spaced 25 kilohertz apart and medical telemetry channels are all set 12.5 kilohertz from a PLMR channel.
And this all changed when FCC started refarming PLMR channels so that instead of a channel being spaced 25 kilohertz apart, they were now being moved so that the channels were spaced only 6.25 kilohertz apart. This would allow more PLMR channels to be used in a given area. Unfortunately for healthcare, this means that once again medical telemetry is getting squeezed out.
This refarming of tighter PLMR channels began in 2001 for the 450 to 460 megahertz band and just began in January of this year for the 460 to 470 megahertz band.
Slide 12 shows how PLMR channels and medical telemetry worked before the refarming.
Medical telemetry is represented by the yellow bars and PLMR by the red bars. Note the spacing of 12.5 kilohertz between the medical telemetry and PLMR to avoid interference between the two.
If we turn to Slide 13, this shows what happens after refarming.
PLMR can now lie directly on medical telemetry frequencies. In addition, adjacent PLMR channels can also be only spaced 6.25 kilohertz away from a medical telemetry channel which may not be sufficient to avoid interference.
Turning to Slide 14, what does the -- what does the future hold for medical telemetry in this band? The bottom line is continued use can be risky.
Unlike medical telemetry in a TV band, medical telemetry in the PLMR band is competing with transmissions that are mobile. PLMR is used by taxis, delivery trucks, police, ambulance -- all of which are coming and going from healthcare facilities all the time.
In addition, these PLMR transmissions are also much stronger than medical telemetry signals on the order of 2 watts or more compared to only about 20 milliwatts. There really is no reliable way to predict when interference can occur -- how will you know whether that taxi driving up to your hospital is using PLMR on the same frequency that one of your telepacks is using?
In addition, FDA has been recommending for the past several years, most recently in November of 2005, that healthcare facilities migrate their medical telemetry out of the PLMR bands.
As stated in the November 2005 public health notification, according to tests conducted by FDA, the transmitters operating under new licenses in this frequency band can interfere with medical telemetry systems. This could lead to lapses in patient monitoring and missed alarm events -- putting patients at risk.
The anticipated interference will not be limited to urban areas. Any medical facility in the vicinity of mobile radio could be affected.
Moving on to Slide 15, over the past several years, telemetry has evolved in many ways. Instead of simply providing only ECG monitoring, today’s devices can provide both pulse oximetry and non-invasive blood pressure monitoring using patient-worn devices.
In addition to narrow band transmission, today’s telepacks are capable of spread-spectrum transmissions such as frequency hopping in direct sequence. Spread-spectrum transmissions allow those signals to be spread over a wide range of frequencies as opposed to the fixed frequency narrow band devices.
Some telepacks are also capable of supporting bidirectional transmissions, allowing communication both to and from a central station. These are bidirectional along with spread-spectrum transmissions and can allow for more robust communication between a telepack and a central station.
Bidirectional communication can permit the resending of lost data. And spread-spectrum transmission can be less susceptible to interfering signals than narrow band transmissions.
Another change that has occurred is that the difference between telepacks and small portable monitors has blurred as portable monitors continue to shrink in size, some being as small as 2 pounds.
Continuing on with the changes that have occurred with telemetry, on Slide 16, we see that in addition to medical telemetry in the TV and PLMR band, medical telemetry is now also available on two additional bands -- the wireless medical telemetry service or WMTS and the industrial scientific and medical band or ISM.
Let’s start out with WMTS on Slide 17.
It was created in October of 2000 largely as a result of the Dallas incident in 1998. WMTS actually covers three frequency ranges -- 608 to 614 megahertz, this range corresponds to TV Channel 37 which is the channel that we skipped over in the discussion of telemetry in the TV bands; the upper WMTS band includes 1395 to 1400 megahertz and 1427 to 1429.5 megahertz. Notice that in this last frequency range, the frequencies of operation changed to 1429 to 1431.5 megahertz for seven localities.
Medical telemetry operates as a co-primary user in these frequencies along with radio astronomy and government operations. Because of this, there may be some restrictions on use of some WMTS frequencies depending on location.
Registration for use of WMTS telemetry with the American Society for Healthcare Engineering or ASHE insures coordination of frequency use.
As you can see, there are a number of intricacies involved with the use of medical telemetry in this band.
Let’s turn to the next slide covering the other band available for medical telemetry, the ISM band.
ISM telemetry uses cross industry standard wireless protocols such as IEEE 802.11 family of standards, including 802.11a, 802.11b, 802.11g and frequency hopping.
Use of the ISM band is not specific to medical telemetry; many different wireless devices such as laptops and portable phones use the ISM band. As such, this requires that a hospital coordinates interoperability between its telemetry systems and other wireless systems such as the wireless local area network.
With these four bands now available for medical telemetry use, ECRI was interested in seeing the breakdown of what bands hospitals were using and we conducted an online poll at our Web site in January of this year asking the question: What band does your system use? And the poll results are presented on Slide 19. And while our poll doesn’t represent a comprehensive review of all hospitals, it does reveal some interesting results.
Not too surprising WMTS is the most common band to use for medical telemetry. What is a bit surprising is that the second most common band is PLMR telemetry which is, as we discussed, becoming riskier to use in light of the refarming of PLMR and the granting of additional PLMR licenses at the start of this year.
Looking over the results of the poll that Terrie just went over for this audio conference, we see that WMTS as well came up as the most common band in use. However, unlike the ECRI poll, the TV band, and not the PLMR band is the second most common band in use. And this may reflect that hospitals are moving out of the PLMR band as the year progresses.
In conclusion, there certainly have been a number of significant changes to medical telemetry over the past few years, and now more than ever before, we need to be proactive in determining the risk of interference to your medical telemetry operations. The bottom line is there is no simple answer to what is the best frequency to use for medical telemetry, rather it will depend on the specific circumstances at your facility and each facility will need to do their homework to determine which approach will work best for them.
And on Slide 21, I’ve listed a few articles from our Health Devices journal for reference. And that wraps up my part so I’d like to pass it back to you, Terrie.
Terrie Reed: Thank you.
Now we’re going to take just a few minutes for some general questions about the technology, maybe not specific application kinds of questions, but if you have some clarification that you want from Rich, please dial in now.
Coordinator: Again, as a reminder for our listeners, that’s star-1 for any questions or comments at this time.
Again, press star-1 please.
And I show no questions, ma’am.
Terrie Reed: Okay, then we will move on to Rick Hampton.
Rick is the Wireless Communications Manager for Partners Healthcare System in Boston, Massachusetts. He’s responsible for the overall coordination of activities relating to the safe and effective use of wireless communication technologies at Partners Healthcare and its affiliates.
In addition to leading the wireless task force, he coordinates efforts to provide safe and effective wireless deployment, educate Partners departments on proper wireless deployment methods and technologies, maintain and disseminate all policies regarding wireless technologies, and investigate electromagnetic compatibility and interference issues.
Rick is also active with IEEE and other organizations trying to develop standards and guidelines for implementation of such safe wireless medical systems.
Go ahead Rick.
Rick Hampton: Thank you Terrie and it was very nice of you to ask me to be on this conference call.
Okay, so we’ve heard a little bit about me, we’ll go to Slide 2.
And for those of you who have not heard of Partners Healthcare systems, just a brief introduction: We’re a group of hospitals up in the Boston area; you may have heard of Mass General and Brigham and Womens, some of the others are community hospitals. But we are basically a group of hospitals like yourselves trying to deal with this issue of telemetry and interference.
Let’s go on to Slide 3.
So there are a few things I’m going to discuss. I’m going to play off of Rich’s very well done introduction to the history of telemetry, I’m going to discuss some important EMI case histories, some of the FCC regulations and what they really mean, touch a little bit on spectrum management, and like Rich, I have a couple of reference sites for everyone to use.
Slide 4 - So it’s interesting to note that none of these telemetry systems are without risks. You know Rich has covered how some of - how the WMTS systems came about and where we’re going with those, and everyone when WMTS came out thought that that was going to provide protected spectrum. Well it does but protected should be in quotes, and I have a few definitions and I’ll give those to you.
So, we’re going to look at the different telemetry systems and I’ve referred to them here as Part 90, Part 15, and Part 95. Those part numbers refer to the section of the FCC’s rules that govern the radio service indicated. So if you really -- if you wanted to look up the actual rules, and I would suggest anyone that’s interested do this, there’s a site online where you can go to the Federal Register and you can browse the different sections and you’d look and CFR 47 which is the rules promulgated by the federal communications commission. You could look in these different parts to find the exact rules as they are today that govern these different systems.
So we’re going to look at EMI cases in all of them.
So going to Slide 5, Part 90 is the oldest of the telemetry services and at one point in time you actually had to have a license in order to operate each and every transmitter that you use. And back in those days I was a clinical engineer with Hurley Medical Center in Flint, Michigan and in 1989, we had an incident where one of our telemetry channels started having severe interference.
To make a long story short, it turns out that the frequency coordinator responsible for assigning frequencies to the different radio systems in that part of the world had assigned the same frequency as our telemetry system to a paging company who had a digital paging system located on the roof of our hospital. So as you might imagine every time a page was sent from this system it basically destroyed that particular channel.
So this is not really a new instance and it points out to the fact that the operation in Part 90 has never been completely risk-free or trouble-free.
Most recently though with the release of the newer licenses that Rich talked about, I’ve received reports from a hospital in New Jersey and I was in contact with them as late as yesterday afternoon. They are suffering from interference to their Part 90 medical telemetry in the land mobile radio band. It is intermittent at this point in time. It is something that they can live with while they investigate whether or not that they need to replace the system. I think it’s a pretty simple question to answer myself.
But they had the manufacturer come in. The manufacturer did a quick study, basically told them that they were suffering interference from land mobile radio and provided them no supporting evidence or data at all. So the hospital is trying to collaborate this with a third party investigator and that will probably take about another two weeks then I think it will probably wind up moving.
But the point here is the interference came on quickly, it is intermittent, they’re not sure when they’re going to have problems with the telemetry system and when they’re not, but as this point in time it’s only some of the telemetry channels are affected, but they are seeing this problem and they were not able to predict it.
Let’s go on to Slide 6.
Part medical or Part 15 medical telemetry and the TV white spaces; this was the stuff that Rich mentioned earlier in the Baylor and Methodist Hospital incidents.
It’s important to note that there’s a false assumption that there is a list of TV stations out there and if you don’t have a TV station in your area that’s on that list, you are safe. That is not true.
Again, as Rich mentioned earlier, the FCC is still issuing new licenses for digital and low power TV stations. The last contact I had with the FCC’s Media Bureau Division, the group that regulates TV stations, indicated that once the analog stations are done away with and the conversion to digital is fully implemented, they will probably be issuing many new TV licenses throughout the United States.
So do not think that just because you have an empty TV station now or an empty TV channel now that it will remain that way. That can change relatively quickly.
There is also a pending proposal to advance - to allow advance wireless services to use the TV white spaces. Primarily the biggest issue here is the new WiMAX service that you may have heard about that will provide wireless coverage, you know, in metropolitan areas. They’re looking for spectrum space.
The talk is that the proposal that the WiMAX systems and these other advanced wireless systems will have to use sophisticated cognitive radio systems that will listen before they transmit. If they hear another station, they will not transmit. If they do not hear a station, they will transmit.
And the question is will these advanced systems be able to hear the very weak signals that are coming from our medical telemetry systems. It is a real problem and you will probably not know that you’re going - that these things are going to be installed because at this point in time, they may be unlicensed.
Let’s go to Slide 7.
If we look at the Part 15 spread-spectrum systems and the ISM band, there are a couple of companies using these systems. As of right now, I’ve not heard any issues of external interference to these systems, however, the issue isn’t the medical system versus the microwave that everyone discusses, it’s more of the medical device versus the network device, the telemetry monitoring voice versus the wireless voice over IP systems.
It’s something that can be managed. Our hospital is using actually just about all of the telemetry systems except the land mobile radio stuff; we’ve converted our telemetry out of that. But we do have spread-spectrum systems in the ISM bands operating in the same floors, in the same geographic areas as our wireless LAN for the IS system. It can be done, it needs planning, and we’ll touch upon that in a little bit.
So the point here is if you plan to use spread-spectrum systems in the ISM bands, it can be done. The biggest interference is the stuff that you’re going to have internally and operating amongst your own systems. So hospitals need to plan for sensible wireless network usage there.
Slide 8 goes back to Part 95, the new WMTS bands. As luck would have it, of all the places that would have to have problems with WMTS, it had to be one my hospitals here in Boston and it has to do with Channel 38 which is an analog TV station and the TV station is WSBK, and I’ll show you a slide from that in a second. But we currently have some pretty severe interference in the upper portion of the WMTS band and it actually meets all of the FCC rules and regulations as they govern TV stations, and we’ll discuss how that happened in a little bit.
There were also three other instances from a hospital in New Jersey, one in Kansas, and one in Ohio. I was contacted by each of these hospitals -- all of them requested anonymity. We’ll get into that if someone wants me to. But the point is that they all have problems with TV 36 and TV 38 stations in their locality.
And it turns out that even these hospitals didn’t have the same problem that we have here in Boston. The problem at these other hospitals seems to be that the telemetry system was not designed to withstand close proximity to these TV stations and so in each case the manufacturer had to come back in and remediate the problem. But until that was done, the hospitals were severely handicapped by the interference.
Go to Slide 9.
Here’s a spectrogram showing you what the situation is here at our hospitals. There are four triangular markers here in this spectrogram. The first marker is at 608 megahertz, the second is at 610, the third is at 612, and the fourth is at 614 megahertz.
All of the spikes you see in the middle of the screen between Markers 2 and 3 are actual telemetry channels. The large spike just to the right of Marker 4 is a carrier for the TV station that’s nearby; it’s actually about 6 miles away. And all of the signals between Markers 3 and 4 are actually the legitimate and legal signals coming from the TV transmitter. And you’ll notice that some of those are of equal amplitude or greater amplitude than some of the telemetry signals and that causes a problem for us in that we cannot use the upper one-third of our telemetry band there.
Go to Slide 10.
So how can this happen?
The FCC’s final rule that established WMTS discussed this a little bit, and I’m just going to cut to the chase to the section that I highlighted. This is with this allocation, grading telemetry to Channel 37, it says, “With this allocation, we are not requiring television broadcasters to protect WMTS from adjacent band interference.”
Basically that means if you have interference from a nearby TV station and that TV station is transmitting according to the FCC rules, there is no recourse for you to have that station either fix the problem, move, reduce the power or anything. The rules -- the FCC rules governing WMTS plainly state that it’s up to the hospital and the manufacturer of the device to remediate all the problems and if they can’t, they are to move to a different band -- the L-band or the 1300 megahertz band.
Let’s go to Slide 11.
And if we look at the regulations that govern the L-band, as Rich discussed earlier, this section is still shared with other operators. There are non-medical telemetry operators such as utility companies that monitor meter reading equipment -- that operates up here.
That has -- I’ve heard but I’ve not been able to confirm that there’s been an issue already in licensing a WMTS system up in this part of the band. I don’t think it was a true interference issue; it was an issue in that the utility company had already staked their claim to this part of the band and was refusing to share it with the telemetry. I believe that was worked out. Again, that’s -- I’ve heard that from a reliable source, but I’ve not heard it firsthand from a hospital.
So there can be some issues with the registering of this.
And then again, the final rule says that we have to share and protect certain government operations. There are some military radar installations as well as radio astronomy here as well.
(Switch) Slide 12, some other important EMI cases.
Basically what I want to say here is that the FCC doesn’t require any particular communication protocol within WMTS and what that means is there are no standards for what particular protocol is used in these telemetry systems by manufacturers. You can have a channelized system like Rich discussed earlier; you can have a frequency hopping system which is the ISM band stuff; and you can have a newer version that’s come out that’s called Smart Hopping and it doesn’t actively hop across frequencies but it only changes frequencies when it receives interference.
The question is how do these things interact if you have several different versions in one hospital or you have two hospitals quite near each other? And there have been cases where hospitals have installed frequency hopping equipment in one portion of their hospital and found that it jammed and interfered with the channelized equipment they had operating in a different part of the hospital. And there’s also been a few cases where hospitals in urban settings where you have basically a hospital, you know, across the street from another one where one hospital will install frequency hopping equipment and it will, you know, interfere with the channelized equipment at the other hospital.
There are ways to mitigate this, but the point is you have to plan ahead and find out what everyone is using in the area before you turn these things on. You can cause interference just by using a different brand of medical telemetry.
Slide 13. I want to talk a little bit about spectrum management and the key to preventing some of these instances.
The first thing you need to do is you need to know your environment. Preferably, you’ll have a spectrum analyzer and you’ll be able to perform periodic spectrum sweeps to establish baseline, you know, electromagnetic environment for your facility and to be able to see any changes. Alternatively, you can hire a consultant to come in and perform these very same functions. At the very least, you need to have a detailed frequency list of every radio and wireless system used in your hospital, and don’t forget to include things like microwave ovens, know where those are, you don’t have to pinpoint those down specifically but you need to be aware of where they are.
There are a lot of hospitals buying these coaster pagers to, you know, help alert patients and visitors when they need to be at certain places. Many of these things can be bought off the shelf and it’s -- you really need to know what systems are being used and where they’re at.
One other thing you can do, and I would strongly suggest it, is when you consider purchasing a new telemetry system, have to manufacturer of that system come in and do an environmental sweep in the region of the spectrum where their system operates to help prevent some of these issues.
Go to Slide 14.
Again, continue to monitor your environment, periodically redo the spectrum sweeps, learn to use the FCC databases and monitor critical frequencies. I’ve got a few other resources you can use, but some of them are the same that Rich had earlier.
The Universal Licensing System will tell you every land mobile radio system in use within a certain radius of your facility, all you’ve got to do is plug in your geographic coordinates and give it a radius and it will spit out everything that’s in use. You can track -- I’m sure your hospital probably has walkie-talkie systems and some other radio systems, you can track those as well using the general menu reports and the Universal Licensing System.
Again, the TV database query will tell you what TV stations are in the area and which ones have just gotten construction permits.
The FCC ID query will actually let you take any device that someone brings in and presents to you as a possible item to purchase. There’s an FCC ID number on that device if it’s supposed to transmit radio frequency. You can look up the ID number on that and there’s a plethora of information that’s available to you when you use those. So I suggest you learn how to use these databases.
Slide 15. Register all of your WMTS deployments. Urban hospitals in close proximity should also coordinate the exact frequency with their neighbors.
This is another fallacy of the WMTS that if you register your stuff, everyone knows what frequency you’re operating. But that’s not the way WMTS registration works.
When you register your telemetry equipment, you simply tell us what block or what range of frequencies that you intend to use. You do not enter every exact frequency. And so, if you have neighboring facilities nearby, you need to talk with them to find out what frequencies they’re using so you can adjust yours around that and not share them.
You need to license any land mobile radio telemetry that you still have. The option now is if you’re going to stay there, you should license it. Licensing does not guarantee exclusive use of a frequency, but it does let the local frequency coordinators know that you’re there. If they don’t know that you’re there, they cannot even begin to think about protecting you.
Slide 16. Plan ahead. Have an escape plan, replace or reconfigure your equipment as needed. This is particularly important if you are still using land mobile radio systems because you never know when that stuff is going to start receiving interference that you can no longer deal with.
Use of unlicensed technology is growing in medical devices. Begin working with your IS team now to ensure that there is smooth operation between the departments.
I’m working with a lot of the device manufacturers and several of the IT companies trying to figure out how we can tie the medical devices with some of the IS systems because there’s only one chunk of spectrum to share and the best way to do that is by tying some of the systems together. So you need to get on good relations with your IS team now to help ensure that that happens.
Most importantly, report all of these incidences of interference to the FDA and ECRI and encourage your friends at other facilities to do the same.
Luckily I’ve talked with a bunch of MedSun hospitals who know the importance of this. But the reason some of -- the three hospitals I’ve mentioned earlier who request to remain anonymous is there’s still a lot of fear, uncertainty, and doubt in what happens when you report these things.
So as silly as it is, people are calling me rather than calling the FDA. You know if I’m the reporting of last resource that’s okay, but I do so reluctantly. The stuff really needs to be reported to the FDA and ECRI and please encourage the other folks to do this.
Slide 17 are some references for the different things I mentioned earlier. Visit these sites, learn how to use these tools. And there are some other documents, if you haven’t already downloaded them on the MedSun registration site, some articles from ECRI, and a couple from (AAMI) that deal with some of these issues, and there’s a better accounting of some of the telemetry issues that I ran into available in one of those articles.
And that’s my presentation, Terrie.
Terrie Reed: Thank you Rick.
That was excellent. And thanks for referring back to the Web site where all these references are.
We will go on now to FDA’s representative and that is Nancy Pressly. She’s currently a member of the Issues Management staff in the Office of Surveillance and Biometrics within the Center for Devices and Radiological Health. And the Office of Surveillance and Biometrics is also where MedSun is located.
Ms Pressly is currently a member of the CDRH Electromagnetic Compatibility Working Group. She also leads the team that developed three FDA public health notifications related to medical telemetry and the WMTS. Ms Pressly is also involved in other projects concerning electromagnetic compatibility, pacemakers and defibrillators, and various other specific device issues.
She holds a BS Engineering Degree in Biomedical Engineering from Catholic University. And she will be talking about FDA’s involvement in medical telemetry system.
Nancy Pressly: Thank you Terrie.
I’m just going to give a bit of a background and overview of FDA’s involvement. I think you’ve gotten the technical aspects of this very nicely from Rich and Rick already.
So going on to Slide 2 of mine.
FDA really began their main involvement in medical telemetry back in 1998 when DTV started interfering with hospitals in Texas. That’s when it really became an issue for us and we took notice of it. We issued a public health notification warning hospitals that this could happen and that’s really the start of our workings with FCC.
We began working with the FCC and worked with them and the industry and the hospitals and the organizations representing the hospitals to get the wireless medical telemetry service in place.
And as we’ve heard from Rick, WMTS isn’t perfect but it is probably better than what we had previously.
Also in 2000, when FCC did go out with their wireless medical telemetry service, we issued a new public health notification trying to make hospitals aware of this.
Moving on to the next slide.
In 2005, we also issued another public health notification warning about the changes that were taking place in the PLMR band, the 460 to 470 megahertz band that you have heard the other speakers speak about. And we really do want to urge people to get out of that band. We don’t think it’s a safe place to be. The problems that are likely to be seen in that band are probably transient and they’re going to be unpredictable because these are mobile radios. It’s very difficult to know when interference might happen, when one of these mobile radios might come in the vicinity of your hospital, when it might leave, and then tracking down the source is going to be very difficult.
So for those reasons, we really don’t think it’s a safe band to be in and we strongly encourage people to get out of there.
Presently, we are continuing our collaboration with FCC. We meet periodically with them, roughly quarterly we meet with them to discuss what’s going on in the medical device area that both FCC and FDA are involved in. We’re working closely with them.
We at the FDA are working on drafting a guidance on wireless communications in medical devices. This a guidance that’s mainly geared toward manufacturers of wireless medical devices but may have some information that would be appropriate to the hospitals as well. And it certainly outlines some of the areas that we’re concerned about.
Moving on to the next slide. I’ve laid out some of the wireless services and wireless bands that are available. There are really three bands that are mainly in use now as we’ve discussed, the WMTS band. We haven’t heard much about MICS band, that’s medical implant communications service and that’s a band that’s used mainly for implants to communicate wirelessly with their programmers, but that is another band that’s set aside for medical use. And then the ISM band.
Within those bands, there are several different protocols for communication. The IEEE 802.11 and the Bluetooth protocols and those are typically seen in the ISM frequencies. But as was mentioned before, there really are no protocol standards for the WMTS band. So that’s one of the things that people need to be cautious about and be aware of.
Moving on to the next slide.
FDA does have some concerns that are specific to wireless communication. We are very concerned about the RF wireless coexistence. And as was alluded earlier by one of the other speakers, the ability of one wireless system to work is probably not so much in question. It’s what happens when it to has to coexist with all the other wireless systems that are in your hospital.
What happens when you get systems together that are using different communication protocols? What’s going to happen? Who’s going to take priority? What’s going to happen to the quality of service for that medical device? What’s the reliability of the data transmission, including the transmission rate and the error rate, particularly when these devices are being used in the real world scenario where there are competing transmissions out there?
We want to ensure that the integrity of the data stays constant and the security of the data.
And that’s one of the things that we need to impress upon the other people in the hospital using wireless systems for the non-patient care wireless transmission is that when you are using wireless transmissions for direct patient care, it’s different than just transmitting any old data or patient record or anything like that.
The problems with the transmission can really lead to problems that could impact directly on the well-being of that patient. And that’s a real concern for us and what’s going to happen in that area.
Moving on to the next slide on addressing RF wireless. The idea of priorities is important and this gets back to when there are more than one wireless system or even just one wireless system, what is the priority of the data that’s being transmitted?
It’s okay if there is a lag in data transmission or packets need to be resent if you’re just sending data that’s going into a medical record. If you’re sending patient critical information such as an arrhythmic event that’s being transmitted that would trigger an alarm and have to trigger intervention, there isn’t room for a delay in the transmission of that kind of data. It has to take priority over any other transmissions that are going on at that time.
Present standards that are out there really do not adequately address wireless medical device concerns. There are safe standards for medical devices but these standards exclude testing in the band transmission frequencies that aren’t wireless which means that the frequencies that we would be most concerned about, what the device is operating in, the testing that goes on, that’s called wireless standard is not performed there.
So there really are no standards that adequately address this in medical devices. That’s why some of the work there, like Rick is doing in IEEE and coming up with standards and guidelines, is very important and FDA is also actively participating in those groups.
You know when you’re looking at RF wireless medical devices and telemetry, you know, there are number of things that you need to consider. You need to consider EMC in general, the electromagnetic compatibility. Just because this is wireless doesn’t mean it’s not going to cause electromagnetic compatibility problems in general.
And then the whole issue of the coexistence, the data integrity, and the data security all have to be addressed. And this has to be addressed not just by the manufacturer, these are things that the hospitals need to consider once this has gone in place in the hospital. The manufacturers all have to do this before they can get a medical device approved but making sure that these remain as the manufacturer intended and some of the responsibility of the hospital once the system is put in place and is in use in your hospital.
Moving on to the next slide. One of the things that we think is most important is you need to report problems to the FDA.
You are all MedSun facilities, so we would hope that you would work through MedSun to report these issues even if they’re not mandatory reportable events - we still want to hear about them. As Rick mentioned, there are hospitals out there that we know are having problems but they’re not reporting to the FDA and they’re not reporting to the FCC.
Without those types of reports coming in it’s very hard for FDA to work to do something to get changes made.
Basically, we’re working on anecdotal, hearsay information without having actual reports. At this point when people ask us, “Well what kinds of problems are you seeing?” and when FCC asks us, “Well what are you seeing your database with problems related to telemetry and other wireless communications problems with medical devices?”
We go back and look in our database and there’s practically nothing there - yet we know that there are problems out there.
So it’s very important that we get hospitals to report these problems, even if they’re transient, even if you manage to fix them, it’s still good for us to know about it.
And that pretty much concludes my overview and my contact information is there on the last slide.
Terrie Reed: Thank you Nancy and thank to all of our speakers.
It’s a very complex subject with complex solutions.
Now we’d like to open up for questions from the audience.
Coordinator: Thank you ma’am.
As a reminder again for listeners, that’s star-1 for any questions or comments and please press star-2 if you wish to cancel.
Once again, that’s star-1 for questions at this time.
Sir, do still have a question?
(Participant 1): I think my question’s been answered already. It’s about cohabitation of frequency hopping and channeling, direct channeling of the telemetry packs.
Coordinator: All right.
Terrie Reed: I had a question about that. Can you explain, I think Rick, it was in your presentation a little bit in Richard’s presentation of what the differences between those channeling and frequency hopping?
Rick Hampton: Okay.
Rich, do you want to do it or do you want me?
Richard Diefes: Well, if you want, I’ll take a stab at it and you can follow up.
Basically, the difference there is that with the channelized what you’re usually dealing with is the transmitter is operating on a fixed center frequency as opposed to the frequency hopping, the way those transmitters work is they actually are as the name says, they’re hopping around in frequencies, so they’re not actually on a single frequency for very long before they move to another frequency.
And the problem that comes in in terms of the cohabitation of those two is that, you’d be at one transmitter setting at a fixed frequency and what happens is that occasionally that frequency hopping might come over and not go on that same frequency. So you start having issues with that.
So there have been some cases where some of this frequency hopping systems have caused problems with the channelized systems in terms of interference.
Terrie Reed: Okay, thank you. Any other questions?
Rick Hampton: Let me add one other thing to that.
The rules require that frequency hopping systems in the WMTS band, the rules require those be able to be throttled back and not hop across the entire band. However, when you restrict the number of frequencies that those devices can hop on, the more you restrict the number of frequencies or the smaller the hop set, the more those act like channelized systems and you begin to lose some of the benefits of frequency hopping altogether.
So the point is they can be made to coexist but the only way to do that is throttle back the hop set on the frequency hopping systems and the more you do that, the more or the less immunity those things have to things like interference, the less number of devices you can have, you know, in your repertoire. So rather than having several hundred you might only have 200 and that type of thing.
So they can be made to coexist but there are tradeoffs.
Terrie Reed: Rick, you also introduced another term called WiMAX. Can you explain what kind of technology that piece for?
Rick Hampton: Yeah. WiMAX is one of the latest unlicensed wireless systems that -- they’re not really sure where it’s going to compete in the market. They think that -- there are many pundits out there who think it’s going to compete with the cellular telephone companies.
One of the primary uses is for providing wireless connectivity to devices that are on the move in police cars, ambulances that type of thing for example. Some people think that given enough time, WiMAX will probably replace Wi-Fi, the 802.11abg system that we have now that provide greater range at greater speeds. We’ll have to see about that.
But that’s primarily what WiMAX is. It’s a replacement wireless technology that’s still kind of on the drawing board.
Terrie Reed: Okay. Thanks.
Coordinator: Thank you.
For any questions or comments, please press star-1 and to cancel, you may press star-2.
(Participant 2): Yes. I have a question about the use of Bluetooth. We have a neurology doc that wants to bring it in to the OR and didn’t really know a whole lot about that and come to find out there’s at least there’s different classes of Bluetooth. I guess apparently different power transmission levels, etcetera. And I was just wondering, what the experts you know, think about the use of Bluetooth technology in a critical care environment such as an OR.
Rick Hampton: Okay. Since everyone’s quiet I’ll tackle it first.
Bluetooth by itself is yet another protocol you used in the ISM bands. It’s unlicensed. And I’m desperately trying to find the power limitations for those three classes that you brought up, but that is pretty much the defining thing.
It’s a frequency hopping system. And like many other frequency hopping systems, it’s quite a robust system. There’s not much that interferes with it. But it can under certain circumstances interfere with other systems. It shares the band with 802.11b and 802.11g.
If you have -- I believe it’s a Class 1 system so you have to forgive while my computer is chugging along trying to dig up my notes.
Anyhow, the highest power system I believe is a Class 1 and the lowest is Class 3.
(Participant 2): That is correct.
Rick Hampton: Okay. Thank you.
So the highest power system, the Class 1s can - I have been able to demonstrate repeatedly that high powered Bluetooth devices can interfere with Wi-Fi, the 802.11bg systems up to about 15-foot radius. Beyond that I’ve not seen any problems.
What I would suggest is you do is to find out which systems that are proposing to be brought in, most of them are being used only for the immediate area, 3 to 10 feet and the Class 1 and Class 2 devices can easily operate in that. If you find someone proposing a system uses Class 1 or the highest power, I would suggest you contact the manufacturer and insist on discussing why they feel need that high power.
I’ve talked with three different device manufacturers and every one of them told me the same thing: I don’t know much about radios. I just thought that more power was better.
(Participant 2): Right.
Terrie Reed: Yeah.
(Participant 2): Our options here look like we have a choice to go at least to Class 2 if not a Class 3. Right now we’re just talking about interfacing generic devices such as printers, things like that. But you know, we do have a wireless LAN in the OR as well and we were concerned about interference. So you did answer the question.
Rick Hampton: Yeah. And the other thing you might do is talk with the folks at FDA because I know the last time I was down there, they took me on a tour of their RF test area. And they were actually testing some OR devices that use Bluetooth. And so they may be able to give you some tips as well. But generally, if they operate the thing with a reasonable amount of power, it’s not a problem.
(Participant 2): Sounds good. Thanks a lot.
Coordinator: Thank you.
Once again for questions, please press star-1 and to cancel you may press star-2.
Our next one in queue comes from (name).
Terrie Reed: Can I just interrupt for one second? This is Terrie.
We have (Don Witters) on the line from FDA and I don’t know if -- I think he’s involved with some of that Bluetooth testing, I don’t know if you would like to comment on that.
(Don Witters): Thank you Rick for mentioning us.
We have performed some testing as Rick mentioned, and the Bluetooth can indeed interfere with 802.11 systems. This is not anything new but we have been able to perform some experiments and are publishing a paper on that right now.
I just want to mention that the interference is not the only issue as Nancy mentioned. Our concerns include security.
And one device system that we looked at included both Bluetooth and 802.11 to control up to 8 surgical devices. And our question was what happens with the guy walking down the hall who has a Bluetooth enabled PDA. Can he see your device system, which is called discovery, in these types of applications? And if he discovers it can he change it? You wouldn’t want somebody to change an electrosurgical device setting while you’re in the middle of an operation.
So in that case, we and the manufacturer were very concerned. The manufacturer did a number of tests, and in fact went back to the chipset manufacturer and had the RF power turned down so that it would be less likely for the wireless signal to go outside the surgical room. Plus, they added additional security on the systems so that only those pieces of the system that are uniquely identified could actually tie into their wireless device system.
Terrie Reed: All right.
Any more questions? I thought I interrupted someone.
(Participant3): Yeah. Okay, thanks. That was kind of where I was headed was that last answer there.
We are going to an ECG management system and part of that will be the 12-lead products are going to be wireless or have that option and it’s 802.11b standard off-the-shelf Cisco card. I was wondering if there is any HIPAA requirement or as far as security goes, that pretty much off-the-shelf is okay?
Rick Hampton: Let me handle that one or at least take a first stab at it.
(Don), thank you for bringing up the issue of security, I forgot that that was probably be going to be in the scope of this and so I didn’t mention it. But when it comes to the wireless systems especially 802.11abg I found that the security problem we wanted the biggest pitfalls of these devices.
The security standards were just ratified a couple months ago. Manufacturers are still trying to build them in. What we’ve seen presented to us in terms of medical systems is going to be on the wireless land. We’ve had a number of manufacturers come in and tell us we understand HIPAA and we’ve taken that into account.
What we’ve done is we’ve encrypted our data both in our device and in our servers so that there’s essentially a secure tunnel between the two. And that, as far as we’ve been able to determine that does indeed meet HIPAA requirements.
However, in doing that, the manufacturers have been the basically using devices that have been designed and manufactured for the consumer world. And the consumer world doesn’t need nearly as much security. So what we find is that device manufacturer has taking the stance that they’re encrypting their data and therefore the only security protocol that they’re running is WEP or the wired equivalency protocol and it originally came with 802.11b and was essentially proven to be inadequate before it even hit the market.
I have been having many conversations with device manufacturers and IT manufacturers over the last couple of months and years trying to get them, badgering them, bullying them in some cases to consider upgrading their security standards. It’s happening but it’s slow.
So the thing you need to remember when you look at some of these systems is the rest of the security issues, if you’re not comfortable, make your views known upfront before you purchase for the systems.
Terrie Reed: Thank you.
(Don Witters): Let me just – this is (Don Witters). Let me just add on to that a little bit. I thought I heard the questioner ask about off-the-shelf.
(Participant 3): Yes, with the Cisco card. And I guess the encryption could be, you know, from the manufacturer. But they’re still just getting into it, so yeah.
(Don Witters): Well, let me just make a quick comment.
Off-the-shelf doesn’t mean it’s good enough for medical. And that may be one of the points Rick and Nancy were highlighting.
I have seen recently a submission for another device, another surgical controller, that once we were clear about our concerns to the manufacturer they went back and did some additional testing of their access points and their wireless system. And lo and behold found that even though it was standard IEEE, the susceptibility was not the same from one unit to another. A model unit of IEEE 802.11 from one wireless manufacturer did not pass the device manufacturer’s own coexistence testing criteria and another make and model did pass.
And further, the IEEE standards that these wireless systems are working on do not include a test method or a test requirement. Yes, they do validation testing to make sure that they’re working. Of course they do that before they put it out in the market. But there really is no test method. Only now is IEEE working on that because they see the concerns and issues particularly in the medical area that really need to be addressed, and that for some medical uses the concerns are above and beyond, as Rick pointed out, the consumer type issues.
Medical is a different animal. It needs to be treated very differently. Off-the-shelf may not be good enough.
(Participant 3): Thank you.
Coordinator: Thank you.
Again it’s star-1 for questions and star-2 to cancel.
You may ask your question, sir.
(Participant 4): During a certain time frame, we were notified by letter when a new TV station frequency was going to be transmitted. Are we outside that timeframe now with the TV stations now begin transmitting without notification?
Man: The last I heard they were still required to send those notification letters out. However, what I’ve seen happen is the notifications go everywhere except to the person that needs to see them. There’s still a lot of confusion among the TV stations as to who these letters actually go to.
(Participant 4): Okay. Thank you.
Coordinator: Thank you.
And it’s star-1 for questions.
(Participant 5): I’m at the hospital here where we’re putting in a new building and in that, we’re going to be putting wireless system for our IS department and also a wireless for portable monitors for transport and they’re both on the 2.4 Gig range. Is there any particular questions or concerns I need to bring up while we’re setting these all up that still need to address?
Rick Hampton: Well again, let me try first stab at it.
It’s going to exceedingly difficult for your establish two wireless networks using the same three frequencies that are available.
(Participant 5): I was told there were 11 frequencies.
Rick Hampton: There are 11 frequencies. However, all but two or all but three overlap. In other words, Channel 2 overlaps significantly with Channel 1 and somewhat on Channel 6. And as you go up the scale, Channel 5 overlaps tremendously with Channel 6 and a little with Channel 1. As you switch it over to Channel 7, it overlaps at lot with Channel 6 and some on 11.
The only three channels that do not overlap on a significant basis are Channels 1, 6, and 11, that’s here in the United States. There are some other channels available in other countries but that doesn’t apply to us here.
So you’re going to have to work real close with your IS department.
Now I know that a couple of the manufacturers that I’ve talked to say that the best thing to do is reserve one channel specifically for the medical telemetry use. The problem is that it leaves only two channels to coordinate the systems for the IS department. And it kind of comes back to the old map coloring problem. How many colors do you need in order to color every country on a map without having colors from, you know, adjacent countries being the same? You need four. We’ve got three.
(Participant 5): Okay.
Richard Diefes: Let me ask this question. This is Rich from ECRI.
Were you intending to use the same infrastructure for both of those systems or were you intending to have two separate infrastructures?
Rick Hampton: We are running two separate infrastructures.
Richard Diefes: Okay, okay.
Rick Hampton: And the medical system is a fixed frequency. And we’ll have to pick one. And so 1, 6, or 11, I’ll try to push for.
Let see (unintelligible) -- okay, I’m going to be real honest with you. If you get this working, I want you to call me and let me know how.
Richard Diefes: Okay. Okay.
Terrie Reed: On that encouraging note, are there any checklists when working with manufacturers or IS department that would be helpful? Or are they already on the references and I just haven’t seen that? You know, questions to ask or…
Do either of you know? Any of you know?
(Don Witters): This is (Don Witters).
There is a recently published ISO document ISO/TR 21730 “Health Informatics – Use of mobile wireless communications and computing technology in healthcare facilities – Recommendations for the management of unintentional electromagnetic interference with medical devices” that gives a nice overview of information for some of the issues that have been discussed today. It is available to help people with wireless technology.
Also, as Rick and others alluded to, there is a document that’s being developed by IEEE through the 1073 standards group that is rather detailed and very nice. Both Rick and myself have been working in the group developing. The document describes a general overview about deploying wireless into health care and gives examples. I think the document describes up to 10 or 12 specific areas within healthcare where specific kinds of technologies may be better suited and others perhaps are not as well suited. Everywhere from transporting the patient, to the patient room, to the OR, and to several different specialized areas within the hospital.
The document hopefully will be coming forth this year and is planned to be followed up with some other documents.
This need for this type of document has been recognized for a while. And manufacturers and vendors, and people such as Rick and others, have been working on exactly that kind of information. What do you really need to know to implement and deploy these wireless systems so they’ll work properly and do the functions that they have to do and minimize some of the concerns.
As Rick will tell you nothing actually works completely 100%, but with that going in mind, they can be made to work reasonably well.
Terrie Reed: And what question, you know, the right questions to ask.
(Don Witters): Yes, exactly.
Rick Hampton: Indeed. We’re also putting in, I think, (cows) as they call them, computers for transmitting all the patient data. So I’ll bring up the issues with security that was mentioned earlier.
(Participant 5): Laptops and transmitting data or so.
Rick Hampton: Is this still the gent who’s going to deploy both medical in IS systems?
(Participant 5): Yes.
Rick Hampton: Okay. Yeah, it can be done. I mean don’t let me sound like -- nothing is impossible. You can make these radio systems work wherever you want to. But the thing that I’m trying to get out and Don has been - I should point as well as Rich, you can’t just throw them together. It’s not that simple. You really do need to do some engineering upfront in order to know exactly what kind of loading that you’re going to be having on the systems.
If the only for example that you’re going to have as the computer on wheels, you probably won’t have much of a problem. If however, you decide to use computers on wheels, active RFID tags operating on Wi-Fi and voice over IP phones and operates over the Wi-Fi, you’re going to have problems.
(Participant 5): Okay.
Rick Hampton: So one of the first things you need to do is determine exactly what you see the uses of wireless in your hospital are going to be. If you’re going to use a lot of stuff, it’s not going to be as simple as claiming one channel for medical and leaving the other two for the IS. It just won’t work.
(Participant 5): Okay. I’ll talk with the IS department.
Rick Hampton: Yeah. If you want to, I mean I don’t know if this is the way to do it, but you can give me a call, you know, afterwards and I can help you with some of this, because we have to do some of it.
(Participant 5): Is this Rich or Rick?
Rick Hampton: This is Rick.
(Participant 5): Rick. Okay.
Terrie Reed: I think we might have time for one more question.
Coordinator: Certainly. Thank you.
You may go ahead, sir.
(Participant 6): Yes. My question is with the hospitals going to more wireless devices, I mean, we’ve got IV pumps are being put in now into the system that you’re going to have a massive updates of medicine support and everything. And of course, you’ve got wireless tracking devices that are coming in. And what is then -- has anything been looked to ensure that when so much is put into systems that they will be protected from somebody coming in using this for something else and then also you have to change your frequencies on it, and happen to spend more money.
Rich: Well, I believe with the infusion pumps I believe most of them are working on that 802.11b which I mean is basically wide open. There’s no guarantees that something might not come in and you know, pop down right on top of that. There needs to be some coordination.
And the other problem is you know 802.11b is somewhat becoming yesterday’s technology as we’re moving more towards either the 802.11g or 802.11a. So there’s a question about infrastructure for the future.
And if you want to add anything as well, Rick?
Rick Hampton: Yeah. I was going to let someone else take a shot.
Terrie Reed: Yeah. One shot.
Rick Hampton: Yeah.
You bring up a good question. And my answer to that is the days of buying equipment and installing it and forgetting about it are over. If you intend to purchase wireless systems, I don’t know, hospital is not looking at it. You need to find some way to fund or partially fund an activity for someone to continuously monitor those systems.
I’m fortunate here. My only job is to worry about wireless systems. I actually report to IT, but I’ve been a clinical engineer for a number of years. I spend more of my time with clinical engineering than I do IT trying to make sure that their systems are going to continue to operate.
The problem with using unlicensed bands it is to some degree free for anyone to use as they see fit. Luckily, with 802.11a, 802.11b, and 802.11g, those technologies are fairly short-ranged systems. So what I’ve seen so far in interference that we potentially have with that really is generated by ourselves.
The caveat to that is if you live in a larger metropolitan area, I obviously live in Boston, you might find yourself in the next wave of wireless world where they’re going to install a citywide Wi-Fi system, and that’s where I find myself.
I’m actually on the Mayor’s Commission on the technical committee to look at this. My only job there is to make sure that the new installation that they put in will provide wireless communications anywhere in Boston doesn’t interfere with our hospital.
You’ve got to be proactive with this.
(Participant 6): Right.
Nancy Pressly: I was also going to add in from the FDA perspective that there really isn’t anything that we can do on the pre-market side that will stop all interference. With the way the regulations are setup, we can’t do that. It has to be that once the systems is out there, somebody has to be paying attention to what’s going on in their own hospital and what’s coming in and knowing both, as Rick said, what’s coming in on the medical side and what’s coming in on the non-medical side and if there’s going to be interference. I think we need to stress that. But it’s very important that the hospital take responsibility for what’s coming into their hospitals and what’s going to be operating there.
(Participant 6): Can I ask a second question? Is there any, in the future, is the government or the FDA, FCC looking to set aside certain frequencies since ABs are going to be strictly for medical and nobody can go in and out of those except for medical or anything like that?
Nancy Pressly: That’s basically what WMTS is.
(Participant 6): Okay.
Nancy Pressly: I don’t know that there are options with that anymore.
(Participant 6): Okay.
Rick Hampton: The only way I can see that happening is if the WMTS frequencies are proven to be not enough spectrum or if there are more problems with WMTS than what have been reported. And frankly, even though that I’ve seen and, you know, told you folks about some of the things that kind of look like the Baylor thing all over again, that’s still quite rare. I mean we’re talking maybe four or five hospitals out of the 6000 plus in the US. That’s not a huge thing to lose sleep over.
(Participant 6): Right.
Rick Hampton: But if we find out that we need more and more wireless capability, and we find out that you know, that what we have isn’t sufficient. I really see the only way to that’s going to change is if when we do have problems, we report them promptly to FDA and FCC.
(Participant 6): Okay. Thank you.
Terrie Reed: Well, thank you all for joining the call. And we really appreciate the speakers that had excellent presentations, and answers to your questions.
If you did not get in to answer - ask a question, please either submit it to the Device Safety Exchange on the MedSun reporting side or send an email to (Chuck McCullough). His email address is on the registration site on the agenda.
Thank you all.
Coordinator: That concludes our teleconference for today. Thank you to all for attending and you may now disconnect.