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Know What Time It Is? Your Medical Device Doesn't
An anonymous reader writes "A man with one clock knows what time it is, goes the old saw, a man with two is never sure. Imagine the confusion, then, experienced by a doctor with dozens. Julian Goldman is an anaesthetist at Massachusetts General Hospital in Boston. After beginning to administer blood-thinning medication during an urgent neurological procedure in 2005, Mr Goldman noticed that the EMR had recorded him checking the level of clotting 22 minutes earlier. As a result, four hospitals in the northeast had their medical devices checked, and found that on average they were off by 24 minutes. The easy solution that devices could have used since 1985? NTP."
Why can't the medical devices be hardcoded to use an NTP server on the hospital's LAN?
You don't need to connect to an outside server. You can easily run your own time source (GPS is really easy these days), or have the devices talk to a single internal server which then securely contacts outward. If they're off, at least they're all on the same time. It's really dangerous if everything is reporting different incorrect times.
The easy solution that devices could have used since 1985? NTP.
Holy hell, what about no? There's a huge reason why hospitals try to keep off networks, especially public ones. Do you really want to connect all the timing devices in a hospital to an outside public server? Because running it yourself does no good, it can just fuck up all the devices in the hospital.
Sometimes the ideas non-thinking geeks come up truly scare me.
No one said the NTP server had to be external. NTP is just a method to keep a bunch of clocks synchronized to an arbitrary master.
Sometimes the stupidity of non-technical and non-thoughtful people scare me.
NTP is just a protocol that you can implement. There are solutions that you can install internally that don't require internet access. Just stand up your own internal NTP server and have your own internal official time (possibly synced to something more authoritative). I agree with your sentiment about keeping sensitive medical equipment disconnected from the internet but with hospitals becoming more and more interconnected and not having their own physical infrastructure to do so, the internet looks like it's probably the best option. Yes, there are way to protect your traffic and all that but I must be pedantic and point out that NTP does not mean you must use the common servers available on the internet.
My work here is dung.
hospitals try to keep off networks, especially public ones
The sysadmins try, but fail. Most hospital networks and devices ARE connected to the internet in some way. Doctors want their access from the various desktop machines, of course, but many of the diagnostic machines offer things like "click this button to email the ultrasound pictures". So they do.
I was appalled to learn this a few years ago from a hospital sysadmin here on /. The thing he pointed out is that Doctors are Gods. If they say "This thing can email pictures? Well yeah, hook it up!" then the sysadmin has zero choice. Holes get punched in firewalls that should never have been punched, and the gear gets hooked up.
And because medical devices are certified only to work with a particular operating system at a particular patch level, they don't get upgraded unless the vendor comes out with a new certified patched OS. That means the ultrasound machine sitting on that cart might still be running Windows XP SP 1. It's crazy.
NTP would actually be the least of their worries. That's something they could more easily house internally.
John
Better yet: this is not an application that requires microsecond precision--within a minute or two is fine, particularly as long as all the clocks agree with each other. Completely private network with a master NTP server that is updated by hand every week or so should work fine.
Look if the options are 24 minutes of random error or say 24 seconds of consistently biased error in all the devices in the hospital, I'll take the consistent bias any day. The point of all of this is so that a nurse walking into the room and seeing a blue lipped coma patient can determine things like how long has it been since the monitor whose leads fell off last recorded an accurate O2 saturation.
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Why does clock drift happen? It doesn't need to happen. It can totally be avoided. It only happens because the equipment manufacturers design inaccurate clocks to save money.
My quartz LCD watch from 1985 was accurate to within 1 second per year. That would WAY outlast the usefulness of the medical device. There should be no way in the world that device was off by 24 minutes.
Right now, I'm dealing with the same problem in my brand new car. It has a fancy on-board computer with a screen that tells me gas mileage, service info, mp3 and radio interface, etc.... The clock is ridiculously fast (gains 3 minutes a week). My new $20,000 car should have a clock in it at LEAST as accurate as the watch I can get from a happy meal.