Thursday, March 15, 2007

More on Cellphones in Hospitals and How Doctors Deal with Evidence

 
Last Friday I mentioned a study done at the Mayo Clinic where they looked at the practice of banning cellphone use in hospitals [Cell Phones Can Cause Death in Hospitals]. The study concluded that there is no scientific evidence to support such a ban. Cellphones and BlackBerry's do not interfere with hospital equipment, according to the study.

Tuesday's Globe and Mail had a skeptical front page article on banning cellphones in hospitals [Hole Poked in Hospital Cellphone Shroud].
Cellphone use does not interfere with medical equipment and should be allowed in hospitals, according to a study that turns years of warnings on its head.

The study comes amid a sharp debate within the medical profession, with some institutions beginning to loosen their rules while others stick to the view that the devices can be dangerous to patients.
Among the people interviewed was Chris O'Conner at Mississauga Trillium Health Centre. This large teaching hospital is part of the University of Toronto Medical School. It's my local hospital and I've been there many times, both as a patient and a visitor.

Trillium lifted their ban on cellphones two years ago. Not only that, the staff is encouraged to communicate with each other using BlackBerrys and other devices. According to O'Conner, this has not only improved efficiency but also enhanced patient safety by avoiding communications lapses.

So, why are cellphones banned at other hospitals? Is this a problem? I don't know whether you could say the ban is a serious "problem," but it sure is an inconvenience. For parents sitting in an emergency waiting room for 6 hours it is frustrating to have to rely on a pay phone to keep others informed of what's happening. For those of us who are picking up someone from a hospital, it is annoying to not know when a patient is about to be discharged. (We recently had to pick up a patient from a large downtown teaching hospital. Fortunately they don't ban cellphones so we were able to keep in touch with the patient and find out when he was going to be released.) For patients in a hospital bed it is sad that they can't use their cellphones to talk to friends and relatives.

These concerns are real enough but my main interest is the conflict between rationalism and superstition. The Globe and Mail also interviewed spokeswoman Brandy Delves from a major Vancouver hospital.
A spokeswoman for Vancouver Coastal Health said last night that cellphones and other handheld communication devices continue to be banned near sensitive equipment there, including ventilators and incubators.

While a few hospitals have begun to buck the trend, conventional wisdom supports the VCH's view that these devices could interfere with crucial equipment.

Typical of this concern were warnings from the U.S. Federal Communications Commission that electromagnetic waves from cellphones could shut down electronic devices in hospitals.

These fears were firmly enough entrenched to have made their way into popular legend.

According to an e-mail that made the rounds in 2003, a young girl died during a routine operation because "some idiot" used a cellphone near the operating theatre.

"Be compassionate," this e-mail went on to urge. "Do not use your hand phone at any hospital or places where you are told not to use it. You might not be caught in the act, but you might have killed someone without knowing it."

That message was later debunked by snopes.com (an Internet site about urban legends), and, according to a study released by the Mayo Clinic, the fears it addresses are groundless.
The article goes on to note some of the findings of the Mayo Clinic study then returns to a comment from the Vancouver Hospital.
But the policy-makers at VCH are not convinced. Spokeswoman Brandy Delves said the hospital has had the same policy since 1996, banning cellphones and other hand-held communication devices in key areas. "We have reviewed all the recent literature and have decided to keep our current policy," she said last night.
This is interesting. It's very hard to prove a negative so one can't expect absolute "proof" that cellphones are harmless in a hospital setting. Once the idea of possible danger has been planted it always seems better to be safe than sorry. Nevertheless, all of the so-called evidence of danger has been refuted and there are hospitals that have lifted the ban. Those hospitals do not seem to be losing patients due to unexpected equipment failures. In light of data like this why would "policy-makers," many of whom are doctors, not make a rational decision to lift the ban?

What is it about our psychology that causes some people to reject scientific/rational evidence when it conflicts with their superstitions? Even people who are trained in "evidence-based" medicine seem to be incapable of applying the methodology in real life.

9 comments :

  1. I'm a little surprised to see this still going on in Canada, because otherwise my kneejerk response wrt US hospitals would have been that they're afraid of getting sued. But you good folks up North aren't nearly as litigious as we are, no?

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  2. Pay phones? Canadian hospitals have pay phones?

    The last few times I had a relative in the hospital and needed to update the family, I joined a small crowd outside the door, all of us making cell phone calls. At least I live in a mild California climate.

    Karen

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  3. I'm going to go out on a limb here and offer my explanation for why some hospitals are still banning cell phones.

    The hospitals know that a cell phones will not interfere with the equipment, but they don't want people talking on them all the time.

    If you're sitting in the waiting room for hours do you really want to sit next to someone who is talking on their cell phone for hours? If you're in a curtained area of a hospital do you really want to over hear the patient next to you discribe in detail what they've just had done to them?

    Cell phones are banned because the majority of people can't seem to use them and their sence of judgement at the same time.

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  4. My wife was hospitalized recently after a fall and our local trauma center didn't have a problem with cellphones. As a matter of courtesy I left the actual emergency room to make calls but AFAIK it wasn't a requirement. Nobody mentioned a safety issue and the hospital staff themselves used cellphones routinely.

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  5. "What is it about our psychology that causes some people to reject scientific/rational evidence when it conflicts with their superstitions?"

    Are there worthy answers to this question?

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  6. For the same "reason" that people are frightened of "radiation" from mobile-phone comms. masts near schools ...
    In spite of the fact that at a maximum, it is giving out less radiation than a lightbulb!

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  7. I spent a day in Emerg. last week in Surrey Memorial (Vancouver area). I noticed that the ambulance crews seemed to be on the phone most of the time, checking each others' movements, reporting in, etc.

    I asked about making a cell phone call myself, and was told "No problem". Sure lowered my stress level to be able to call work and explain the situation!

    My daughter works in St. Paul's, in downtown Vancouver. She tells me that the doctors there rely on their cells both in-hospital and out.
    ST. Paul's is under the Vancouver Coastal Health Authority, so obviously this "spokeswoman" (Public Affairs Officer, with a degree in Communication, a recent hire) for VCH is speaking only for one hospital. (Which one I will find out, and stay away from.)

    So not all of us out west are stick-in-the-muds.

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  8. Of course electronics (especially displays) and radio transceivers are interfering with other electrical equipment, the question is how much.

    Medical equipment goes through extensive and expensive testing, which is arduous to change, and there is probably not much effort expended on preventing cell phone typical interference above the standards set. (I have participated in other such testing, but not against medical standards.) Ie, it is tested in principle, but no one will use an actual cell phone with its real characteristics during standards testing.

    And there is no guarantee that equipment that is handled wrongly or faulty is as insensitive - in fact, there is practically a guarantee it will not be. But that is presumably what these studies cover.

    Another factor is that early cell phone systems worked with much higher power, while the new systems and especially the efforts to increase efficiency means much less interference.

    Recommendations I have seen is to not allow cell phones within 1 m from sensitive equipment, which seems reasonable. I don't think there are many equipments which functions are especially sensitive to these frequency ranges. (Except typical computers now working at these frequencies.)

    Future problems will be broad spectrum systems for wireless connections. They don't transmit over the noise floor, but the over all noise floor is raised.

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  9. My career was in electronic design before I retired. I also have experience with commercial and amateur radio transmitters.

    Various pieces of electronics are susceptible to interference. The problem is how much investment in testing (and shielding) will give how much security.

    Devices that amplify very small signal levels are more likely to be interfered with. Things like transmitters or digital circuits (computers and anything with a readout) can be sources. Attached wires can be antennas.

    To make matters worse, it is very difficult to get repeatable results when measuring the field strengths generated by various pieces of equipment, even in carefully controlled conditions of anechoic chambers, etc.

    Basically it is a mess to try to prove that something is adequately shielded. Empirically, if no incidents of interference are being reported, then it is reasonable to relax some of the rules.

    I would still hold that certain types of equipment should not have transmitters used in their vicinity, which is what the VCH spokesperson actually said.

    An automated anaesthesia machine or a computer controlled radiation therapy device are the sorts of things where I would advise strictly forbidding the nearby use of transmitters, because of the consequences.

    Routine bedside monitors are not going to directly cause injury. The concern would be that false alarms or false readings could result in bad outcomes. In most cases, I would predict that the anomalous results from the interference would not mimic reasonable displays.

    Slowly, people are becoming aware that humans are poor at evaluating risk. Invisible risks like radio signals, ionizing radiation, pesticides, etc. cause greatly inaccurate estimates of the danger involved. Likewise we do poorly in assessing low probability - high impact risks.
    ____
    Karen, not only that but they take credit cards. I remember being thrilled to be able to announce the birth of my now 16 year old to her grand parents that way.

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