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Biotech

Build Your Own ECG 375

Jason writes "I finally finished documenting my $4 home made electrocardiograph (heart monitor). If anyone is interested or wants to build one for themselves, please come by and take a look. Makes me wonder why medical care costs so much. :)"
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Build Your Own ECG

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  • by robbyjo ( 315601 ) on Friday May 23, 2003 @10:06PM (#6028826) Homepage

    ...please come by and take a look.

    Translation:

    Please slashdot me and don't even peek... :-)

    • So, we could hook the EKG up to his server, and watch it flatline?
    • Re:Please Come By... (Score:5, Informative)

      by Saint Aardvark ( 159009 ) * on Friday May 23, 2003 @10:50PM (#6029007) Homepage Journal
      Managed to snag a mirror while it was previewed to subscribers -- then had to go get beer. Mmm, Rogue Irish Stout. Anyway:

      http://saintaardvarkthecarpeted.com [saintaardv...rpeted.com]

      • Holy crap...262kb/s. I'm going to have to start throttling this somehow. If someone wants to mirror my mirror, let me know and I'll get a tarball your way.
  • by jkauzlar ( 596349 ) * on Friday May 23, 2003 @10:07PM (#6028840) Homepage
    This could make a great gnome toolbar applet. Then I could enjoy watching my heart race when I accidently type 'rm -rf *' in the wrong directory!
  • by m_chan ( 95943 ) on Friday May 23, 2003 @10:08PM (#6028846) Homepage
    when you can tell me how to build one of 'dem four dollar defibrillators. With my steady diet of coffee, butter and bacon, heck, that thing would pay for itself.
  • by The-Bus ( 138060 ) on Friday May 23, 2003 @10:08PM (#6028847)
    And to think that today I used $4 to buy two Nacho Cheese Steak Chalupas at Taco Bell. While you were out trying to save your heart, I was slowly beating it into submission with slightly substandard but confusingly delicious Fast Food(TM).
  • Ahhh! (Score:5, Funny)

    by shivianzealot ( 621339 ) on Friday May 23, 2003 @10:08PM (#6028850)

    I finally finished documenting my $4 home made electrocardiograph (heart monitor).

    From the website:

    Here you will find information how how to build one with less than $10 in parts.

    Lies damned lies!

    • Re:Ahhh! (Score:5, Funny)

      by IvyMike ( 178408 ) on Friday May 23, 2003 @10:10PM (#6028857)
      I'm pretty sure that $4 is in fact less than $10.
    • I'm going to spring for the $30 ECG.

      I learned my lesson with the $4 dentistry set, and even worse, the $4 electroshock therapy machine.

      I STILL can't quite get my hair to stop standing on end. I can't even wear hats - hair pokes through like skewers through butter (which, incidentally, is one of the only things I can eat now thanks to the dentistry set).

      I thank the lord I didn't invest in the $4 eye-surgery kit.
    • Re:Ahhh! (Score:5, Informative)

      by VFVTHUNTER ( 66253 ) on Saturday May 24, 2003 @02:05AM (#6029625) Homepage
      Whether it be $4 or $10, it's a helluva lot cheaper than the roughly $38,000 that people around the country are paying for Lifepak 12 [physio-control.com] monitors. And I would know, being a paramedic. I actually had to do quite a bit of ECG processing during my stint at the local college to get a bachelors degree...I can't decide which is worse for ECG processing, Matlab (which I used) or Visual Basic. Matlab is nice, but at $3000 a pop, Visual Basic is the cheaper way to go. Matlab's built-in functions definitely helped tho (***cringe*** at the thought of implementing the FFT in VB).

      Perhaps the biggest problem with ECG systems is noise filtering. Adaptive filtering has failed miserably; you'd think the engineers designing the systems would implement Bass and Treble-style filters for healthcare providers to use, but condescention has gotten the better of them. Noise makes interpreting an ECG sometimes impossible, yet no such filters. This presents a problem for me on a weekly basis - it is sometimes impossible to interpret the rhythm, because the filters aren't working properly. If they'd only let me adjust the lowpass and highpass cutoff's, I would feel SOOOO much better. And if they'd give me a Savitsky-Golay filter, I'd have a wet-dream....here's hoping.
      • Re:Ahhh! (Score:3, Interesting)

        The problem with noise (more correctly called artifact) is that it can't be distinguished from the signal by filtering - it's in the same band as the signal. These artifacts come from chest muscle movement - breathing, bending, etc. Remember - the signal you're looking for is electrical impulses in muscle tissue. There are always concerns that lowpass filtering of DC offsets will affect the fidelity of the waveform - some of the data of interest is the slow-moving S-T segment (the area just after the 'bl
  • by Mr. Fusion ( 235351 ) on Friday May 23, 2003 @10:09PM (#6028852)
    His vital are dropping, maybe he should have looked into monitoring his school's server.

    - clear -

    Beep beep...beep beep...beep beep

    -Mr. Fusion
  • by Malicious ( 567158 ) on Friday May 23, 2003 @10:09PM (#6028855)
    Beep, Beep, Beep, Beep... Beeeeeeeeeeeeeeeeeeeeeee.......
  • by TheGrayArea ( 632781 ) <graymc&cox,net> on Friday May 23, 2003 @10:09PM (#6028856) Homepage
    Yea, but does it interpret the data. That's one of the big expenses according to her: have the cardiologist examine the data and give his opinion. Since it's all waveform stuff, I wonder how much of that could be automated in the future?
    • Yea, but does it interpret the data. That's one of the big expenses according to her: have the cardiologist examine the data and give his opinion. Since it's all waveform stuff, I wonder how much of that could be automated in the future?

      Its possible to automate alot of this stuff. However, its not as simple as it first sounds. I have used alot of ECG's with automatic interpretation, and they mostly get it right nowadays. About 95% of the time. Which isn't really good enough yet to risk your life on.

      I think that you will find that eradicating the last few percent of errors will get harder and harder, and who is going to back (and assume liability for) any errors if not trained people - be they medical staff or highly skilled nurses?

      I think that by the time that we can have automated diagnosticians, there will be alot of other things in our lives that are far less comples going automatic. Like cars that drive themselves and software computer programmers. But wait, I hear you say, nobody is anywhere near replacing programmers with software - but you think you are going to replace cardiologists?)

      Just my 2c worth.

      Michael
      • You don't really need it to be 100% accurate or not, what it needs to be able to do is know when it's accurate, and when it's not. If the algorithm can determine when it's diagnosis is shaky or not, it can then page a cardiologist. If a cardiologist only has to check up on the 5% of cases that the ECG can't figure out for itself, that's a massive reduction in work load.
      • by VFVTHUNTER ( 66253 ) on Saturday May 24, 2003 @01:59AM (#6029605) Homepage
        It's easy to say that it's possible to automate a lot of this stuff. It's harder to actually implement the automation. Philips owns Viridia this week, and their system is essentially the best on the market.

        Unfortunately, the *best* in the market can only interpret QRS complexes. ECG techs still have to go into the system by hand, and label the PR, QRS, QT, and RR intervals. This is still quite an active area of research.

        And for the record, they're nowhere NEAR 95% accurate. 70% would sound more accurate. And I would know, having been an ECG tech at a the local teaching hospital. The hospital spent $110,000 on the system and we were so unhappy with it that the engineering team came down from Massachusetts.

        The rub? They're using a statistically-based FFT program, and their sample set is ~250 AHA ECG recordings. Humans who are good at ECG interpretation need to expose their neuro-fuzzy brains to at least 2,000 ECG's in order to know what they're doing. And they wondered why we were having problems.

        When the head engineer got up to speak, he made an interesting comment. He said that when he was a student at MIT, a physician from Beth-Israel Deaconess Hospital came to the engineering department and asked if they could analyze ECG signals. They looked at them, and seeing their simplicity, said of course. Thirty years later, he's still working on the problem.

        You'd think he would have tried something other than the FFT by now, but he hasn't. So much for thinking outside of the box.

        --V--
      • by Frank T. Lofaro Jr. ( 142215 ) on Saturday May 24, 2003 @02:51AM (#6029746) Homepage

        But wait, I hear you say, nobody is anywhere near replacing programmers with software - but you think you are going to replace cardiologists?)

        Yeah, first we'd have to program a computer to be arrogant and have a God complex...

    • by Davak ( 526912 ) on Friday May 23, 2003 @10:58PM (#6029033) Homepage
      First thing we were taught in medical school regarding ECG is to ignore the computer interpretation. The sensitivity is way too high; therefore, the specificity is greatly reduced. Thus, the interpretation is seldom useful.

      Where computer-automated reading of ECG is much more effective is in the automated defib units that you might find in airplanes, malls, ambulances, etc. The computer is good enough to know if a jolt of electricity would be helpful in correcting the problem.

      Of course, the expense and the value of ECG is in the physician interpretation. Likewise, an aspirin in the hospital will cost you dollars instead of cents due to administration costs, nursing costs, insurance, etc.

      What has really helped ECGs is fax machines and now the internet. If a health care professional has a question regarding a waveform, they can get it to someone who can give an accurate reading. Soon, if not already, physicians will be able to see the ECG live (and in living color) of patients on planes...

      And quit dogging the editors for posting this... We need more tech-related medicine news. It warms this geek MD's heart.

      Davak

      • what, you from 1985? In 1993, the automated interpetations where pretty good. Most of the cardiologists I worked with seldom changed the interpetation results. We get the info sent to use from the cart, via phone line. The technolgy to do that wwas pretty much in place then. No HP ould charge 2000 dollars for a 2400 baud modem with a special connector. You would think for that money it would be some custom job, but when you took it apart and checked its signals, it was just like a 200 dollar external modem
    • by The Tyro ( 247333 ) on Friday May 23, 2003 @10:58PM (#6029035)
      I can tell you that many of us clinicians laugh out loud at some of the machine "interpretations" that ECG machines generate.

      NEVER trust a physician who allows his ECG machine to interpret your tracing... run for the door... I'm quite serious about that. If the guy doesn't have the expertise to read your tracing himself, don't trust your cardiovascular health to him.

      I've sent people home with ECGs that read ****ACUTE MI***** in large, upper-case font on the top, because the machine was totally, completely wrong. The only thing it's sometimes useful for is in reading QT intervals, and occasionally rate (though the machine can be easily fooled on this one as well).

      Have a doc read it, preferably a cardiologist. Of course, if you don't want to pay a guy like that for his expertise you don't have to... but you get what you pay for.
      • by GlassHeart ( 579618 ) on Saturday May 24, 2003 @12:12AM (#6029260) Journal
        I've sent people home with ECGs that read ****ACUTE MI***** in large, upper-case font on the top, because the machine was totally, completely wrong.

        I'm obviously not qualified to comment on your clinical diagnosis, but this statement worries me. My expectation as an engineer (but not one of medical devices) is not to replace the professional operating the device, but to supplement him or her in a useful way. That is, if I designed the ECG you use, I would like that 99% of the time it agrees with you, and the 1% of the time that it doesn't you take it so seriously that you consult a panel of specialists. That's my idea of a working man-machine system.

        If you regularly ignore its conclusions, then it's better not even having the feature. The one time in a thousand that you're wrong and it's right, you'll ignore it anyway. There's something broken in the system here, in my uninformed opinion.

        • by The Tyro ( 247333 ) on Saturday May 24, 2003 @01:03AM (#6029428)
          No no... I appreciate the input of you guys that actually make the equipment function... the Biomed guys regularly save me (by keeping my equipment running). I couldn't do my job nearly as effectively if it wasn't for the biomedical engineers. I don't mean to make fun of anyone's hard work, and I'm probably being too hard on the people that program these things. Maybe it's the case that the interpretation software is simply in its infancy.

          Perhaps I should expand on my initial comments. A previous poster pointed out that the first thing you are taught in medical school is to ignore the machine read... that's true, and medical students are still taught that way (I teach in an academic setting, and I teach my students the same thing).

          As I understand the machine's algorithms (if somebody who programs these things wants to correct me, please do), they interpret the waveforms based on an ideal model, and attempt to interpret current-of-injury patterns, based on deviation from an expected baseline.

          Many situations make the machine read useless (and to be fair, extraordinarily difficult)... any patient in a paced rhythmn (pacemaker, single or dual chamber), the machine will default, and not give a read. An excellent call for the engineer that designed the machine... reading injury on some paced rhythms can be very sticky, even for an experienced clinician. Some of these machines regularly read "digitalis effect".. a difficult call, particularly in a suspected ischemic or strain-induced ST depression. A noisy baseline (in a patient who's shaking, for instance)will often throw off the machine. Many patients who have known cardiac disease have EKGs that are difficult to interpret, and injury that can only be discovered based on comparison to a previous EKG.

          What I'd like to see is a program that compares old EKGs to new ones, and automatically gives you a change summary (in addition to the tracings themselves, naturally). I could see that being very useful, particularly if it uses the previous EKG tracings to redefine "normal" for itself. That might help the over-sensitivity problem. Many people are walking around with tracings that are nowhere near the classic "normal," but are normal for THEM. What I'm saying is that I'd like to see a program with a dynamic "normal;" one it can redefine on the fly.

          It's not to say that I don't read the machine's interpretation... I do, but I subordinate it to my own clinical interpretation. To be fair, I have the luxury of knowing the history... something the machine may never know, and as any physician will tell you, history makes the diagnosis 80% of the time; the tests are simply to confirm what you suspected all along.

          Maybe if you frame it like that, EKG machine reads don't really need to be perfect... they are, after all, just an adjunct... A human still makes the decisions.

    • I use to be an ekg tech and now code. The ability to interpret an Ekg graphs is not that hard except for borderline cases.
      • I disagree... EKG reading can be quite challenging, and unless you understand the nuances of why everything on that tracing happens like it does... you will miss important findings, particularly subtle ones.

        Dale Dubin [amazon.com]has a book on EKG reading that I'd recommend as an excellent starting point. It's hardly exhaustive, but well-loved by many paraprofesionals.
    • With their "degrees" and their "Training"... always holding us down...

      Hook it up to an expert system and do the same to all the other monitoring equipment you built in the Junkyard Wars stadium and have them all talk together with some sort of secure wireless protocol. Put it all together and you'd probably get as good an idea of what's going on as your average medical technician. The trick is then finding some way to remove that hunk'o'pot roast from your chest and replace it with another one for less th

  • Makes me wonder why medical care costs so much.

    Please... I didn't spend four years at Evil Medical School to work free. Thankyouverymuch.

    Also, can someone please kludge up a serial/usb/bluetooth/etc. link up for this thing? Maybe we can attach them to those computers in the Korean PC Bangs. They'll force people to log off Counterstrike before they play themselves to death.
    /only half-serious.

  • by InterruptDescriptorT ( 531083 ) on Friday May 23, 2003 @10:14PM (#6028875) Homepage
    PLEASE be careful with ECG or EEG circuits, especially if you're planning to use an oscilliscope to see the wave or a data acquisition board to log the data. The pads and the gel used to adhere them to the skin and lower the resistance to get a good signal can sometimes cause current to flow into the body, especially if the circuit is not optoisolated.

    Normally, the skin resistance is high enough to make the current flow negligible; however, when the pads are on, the resistance in the path is very low, and you could seriously injure or kill yourself if even a small amount of circuit flows 'back' through the electrodes.

    Professional ECG machines usually have a lot of protection circuitry on their front ends (the instrumentation amplifiers) as well as between the amplifier and the ADC/output circuits to prevent this from happening. This is obviously even more critical in line- (i.e. 110V or 220V-) operated devices.
    • by pz ( 113803 ) on Friday May 23, 2003 @10:26PM (#6028930) Journal
      PLEASE mod the parent up.

      One of the reasons EKG systems (and I've used a fair handful) are expensive is that they go to extreme measures to insure that under no conditions will excessive current flow through the electrodes. (Ever wonder why hospital-grade power plugs are rated explosion-proof?)

      I cannot comment on the original posting's circuit because it is slashdotted but I'm racking my brains trying to figure out how less than $10 can create a safe circuit ... and it might be possible, maybe, but probably not. Consider that another posting today [slashdot.org] described an electrified jacket which delivered debilitating shocks using a 9V battery as a power source!

      Also, keep in mind that just because a circuit is battery powered does not make it safe once you attach the output to an instrument (computer, oscilloscope, DAC, etc.) which is plugged in to the wall.
      • by mgh02114 ( 655185 ) on Saturday May 24, 2003 @12:22AM (#6029286)
        We cannot emphasize this enough. By applying electrodes or gel to yourself, you are opening yourself up to "microshock" Current at the correct frequency can STOP YOUR HEART (technical term = ventricular fibrillation) This can happen at shocks as low as 300 mA if applied at exactly the wrong time and place. The risk depends on the frequency of the AC current. And guess what the worst frequency is? 60 Hz ... exactly what is coursing through your household current and appliances ... including the computer that you're looking at right now. Building an EKG was a simple homework problem in my Biomed Engineering course. My final exam was an EEG (brain electrical activity, not heart electrical activity). We paid a lot of attention to ground isolation and electrical safety. The key was to use a battery and not be hooked up to AC wall current at all. Unfortunately, the strength of an EEG signal is much less than EKG, and my final exam instrument wasn't working well enough to pick the signal out of the background noise. I got it to work by rubbing the skin off my temples so that the gell pads were on raw flesh (cutting down the resistance). Now that is what I call a "bloody hard" final exam.
      • by sigwinch ( 115375 ) on Saturday May 24, 2003 @01:10AM (#6029461) Homepage
        One of the reasons EKG systems (and I've used a fair handful) are expensive is that they go to extreme measures to insure that under no conditions will excessive current flow through the electrodes.
        Indeed. I took apart a pulse oximeter that used two levels of transformer isolation, and it didn't even make a direct electrical connection to the patient. (They use optical sensors that clip onto your finger.)
        I cannot comment on the original posting's circuit because it is slashdotted but I'm racking my brains trying to figure out how less than $10 can create a safe circuit ... and it might be possible, maybe, but probably not.
        It wasn't safe. Not no way, not no how. But I think you could do a pretty safe one for not a lot of money.

        Use Ethernet transformers for isolation. They're rated for a coupla kV. The FDA probably wouldn't certify them, but I wouldn't be very afraid of them.

        For power, use a 555 timer to drive one of the transformers. On the other side, rectify the current with a diode, filter it with a big cap.

        To get the signal across the gap, use another 555 to turn the EKG voltage into frequency, and send the frequency across using the transformer. Feed it into the line input of the computer, do FM demodulation in software. Alternatively you can use a frequency-to-voltage converter (74HC-whatever PLL). Sound cards are terrible near DC, though, so doing the FM thing would give you the best signal.

        Total cost would easily be less than $10. Even with medical-grade everything, you could probably make a production version for under $30 (in large quantities).

    • by wowbagger ( 69688 ) * on Friday May 23, 2003 @10:28PM (#6028942) Homepage Journal
      EXACTLY! Just what I was thinking when I saw this.

      Kids, DO NOT TRY THIS AT HOME.

      Real medical gear has full galvanic isolation - that means there is NO current path that goes from the patient's body to the equipment - the signals pass through either an isolation transformer, an optocoupler, or a capacitive coupling. That way, any ground leakage in the equipment won't fry the user.

      It takes about .1 amp to kill you dead, and about .01 amp can interfere with normal heart operation. Normally, skin runs about 10 to 100 kohms resistance - to get 10 milliamps you would need about 100 to 1000 volts delivered across the chest.

      When you put the gel on, you reduce the resistance to a few hundred ohms. Now you need only a volt.

      Normal consumer equipment can have "leakage currents" - places current shouldn't be flowing but is. You hook your home-brew circuit up to the printer port on your PC, and maybe you are OK. Then one day, while screwing around with it, a cap starts to fizzle in your power supply, or maybe you reach up to adjust your monitor, or maybe you put your foot on the ventilation register. Then you get to start (posthumously) on the 6 o'clock news.

      At a MINIMUM, you should power the circuit with a nine volt battery, and communicate with the PC via an opto-isolated RS-232 link.

      Even better, splurge and get the real medical isolation amplifier modules. Yes, they will cost a bit more than US$4, but then, if that is all the value you place on your life....

      On second thought - go for it! And make sure you clip the ground lead off your computer's power cord while you are at it. And do it in the bathtub - that will help shield the fnord rays out.
    • by wass ( 72082 ) on Friday May 23, 2003 @11:22PM (#6029113)
      Yeah, definitely be careful. I was looking to do a quick demo of a homemade EKG to some of my physics lab students a few years ago. I was surprised that there weren't that many online resources for homemade EKG's (when all it really takes is some ultra-high input-impedance op-amps). [FYI I did build a simple differential amp with rather high imput impedance (don't remember the numbers) but it was with the measly components I could find at rat shack and it didn't work well at all.]

      While planning this I asked my father, an electronics hobbyist for the past 50+ years, about building such a circuit and he said that the main hobbyist electronics rags such as Radio Electronics and Popular Electronics (which melded a few years ago into Poptronics and then recently folded) refused to publish any EKG schematics because of the possibility of someone electrocuting themselves.

      While any electronic circuit you build will put you at some finite risk, you rarely only probe these circuits when they're powered (usually just for debugging). However, heart monitors are deliberately designed to provide an electrical connection not only across your body but across the organ most susceptible to electrocution (ie, heart fibrillations).

      So definitely be very careful, especially if you connect to a line-powered oscilloscope or other equipment.

  • Cost (Score:3, Funny)

    by c_oflynn ( 649487 ) on Friday May 23, 2003 @10:15PM (#6028886)
    Makes me wonder why medical care costs so much.

    Um I'm assuming it has something to do with this odd word called 'reliability'....
  • Why the cost? (Score:5, Insightful)

    by gmhowell ( 26755 ) <gmhowell@gmail.com> on Friday May 23, 2003 @10:17PM (#6028889) Homepage Journal
    Two reasons immediately jump to mind. First, in order to be used in a medical facility, it has to go through insane amounts of FDA testing and licensing. Second, I think (hope, pray) your doctor has a little more experience and training in reading the output than you do.
    • Uh, this is only a $4 ekg if you don't factor in the cost of the computer. even a cheap emachines computer multiplies the cost by 100.
      a real ekg machine includes stuff like a display and a cpu, and software, and a printer, and shiny chrome knobs and buttons, and a thing that goes "ping" and whatnot. the $4 part of this thing is just an amplifier. you could probably get an ekg machine for around the price of this amplifier + decent computer. of course, the diy version here also can also display pr0n and play
    • the dsoctor training as little to do with the cost of the DEVICE. just the cost of his expertiese.

      Yes, it is pricy to get approval, but the mark up in the medical field is nothing short of gouging.

  • by fm6 ( 162816 ) on Friday May 23, 2003 @10:18PM (#6028897) Homepage Journal
    I hope your next project's not a $10 defibrillator!
  • Jason Nguyen was today expelled from the University of Utah after his home web directory saw a 4,000,000% increade in traffic.
  • The reason medical care costs so much is because the principles of free market are applied to it. And I'm not talking about competition - which is great, I'm talking about option. Free market works well in the places where both the buyer and the seller actually have an option whether to complete the transaction or not. When that's not the case, it degenerates into "pay or die", which is clearly an exageration, but not very far from the current state of affairs.
    • Well, more to the point, the market is broken by the US health care system because the folks who get the benefits generally are not the folks paying the bill. Health insurance, generally funded either by the state or by employers pays the bills, but the patients get the benefits. The normal feedback loop of the market does not close properly.
  • Medical equipment. (Score:5, Insightful)

    by Night0wl ( 251522 ) <iandow@@@gmail...com> on Friday May 23, 2003 @10:24PM (#6028917) Homepage Journal
    Oh don't get me started on medical equipment, [read: I'm going to get started on medical equipment]

    Being disabled (SMA type 2, A type of MD, Donate to MDA!) I deal with medical equipment a lot, less then some in more critical situations, but more then your average user.
    It's outrageous the markup medical tag gives to an item, one of the most outlandish of them that I saw was a flag, a metal mounting bracket, fyberglass rod, and cheap neon flag. You know the kind, sold in the walmart bike department for a measly 3$

    Do you know how much they wanted at a medical store? No you dont.... 18$
    So the price of "medical" is 15$ on top of 3$ It's insane.

    You can buy an Ok car for the price of an electric wheelchair. And that's just for what's on the low end.

    How exactly are people who can't walk suppossed to affoard this shit? Sure it's possible, and often times picked up by the government (thank god)
    And if you're not covered, forget footing this bill your self, unless you've got cash to burn. And it's not like the freedom of mobility is important or any thing. Just one of life's liberties some people take for granted.

    "I wish I could sit all day"

    Fuck you buddy

    Grrr, can you tell I'm bitter?

    And then theres red tape. I've been using this same wheelchair for several years now, it needs replaced. But fighting for them is a nightmare. So much paper work.
    • How exactly are people who can't walk suppossed to affoard this shit? Sure it's possible, and often times picked up by the government (thank god)

      Thank god? Thank god?

      How about thanking ME and all the other taxpayers who make it possible for the distress in what would otherwise be an even more difficult life relieved?

      How about thanking those, who paid such taxes all there life, and then needing urgent care, didn't get it "back" and died as a result?

      I don't particularly mind doing my part to relieve s

    • I've often wondered just what we'd find if we could "follow the money" and see who's actually making the big profits. I have a sneaking suspicion it's the insurance industry. And it ain't just health care they've got their grubby hands in; that "OK car" you mentioned ought to cost a lot less, too.

      Tearing the insurance industry a new asshole is gonna be a big plank in my platform when I run for President in 2012. :o)

    • So the price of "medical" is 15$ on top of 3$ It's insane.

      This is because most doctors specialize in diseases of the rich.

      +1, Tom Lehrer. ;-)

    • by the government (thank god)

      And while you're thanking God for the government (I'll not repeat what the other poster said), be sure to thank them for driving the costs up to that level in the first place.

      I work in the medical industry; I sell and maintain teleradiology equipment. DiCOM stuff, for anybody who knows what I'm talking about. You wouldn't believe the level of testing and certification and approval required for medical equipment. Even our stuff, which is never seen by the patient, has Draco

    • umm, first of all, thank the taxpayers.
      Second of all, don't thank the leaders in our government for another multi billion dollar tax cut when are schools are closing down. How many more multi-billion dollar tax cuts do you think it will be before you get to foot the bill? maybe 1.

      Don't be bitter at the guy who is either ignorant or picked a lame ass way to deal with being uncomfortable. Be bitter at the peopel who keep trying to rip off the system, the're the reason there is so much paperwork.

      yes, people
  • Gotta be certified (Score:5, Informative)

    by jpmkm ( 160526 ) on Friday May 23, 2003 @10:24PM (#6028919) Homepage
    Makes me wonder why medical care costs so much.

    Damn near everything used in a hospital has to be certified to be used for medical purposes. People's lives are at stake, and you have to be sure that your device operates within tolerances, doesn't crash, doesn't electrocute people, etc. It costs money to think of every possible problem and design a device around that. Also, as other people have said, the people that run these things are some of the most educated people in the world. Try to start a hospital with your $4 device and let me know how it goes.
  • by amasci ( 318626 ) <billb@eskimo.com> on Friday May 23, 2003 @10:24PM (#6028921) Homepage
    It's not impossible to kill yourself with a badly-designed ECG device.

    Places like UL/CSA say that voltages under 40V or so are safe. But if you apply it to electrodes pasted to your chest, the unsafe voltage is WAY lower than 40V.

    If you build a simple ECG and connect it to a computer, that computer had better be battery-powered. If not, then you might get a nasty surprise (waking up in the afterlife of your choice.)
  • by rfischer ( 95276 ) on Friday May 23, 2003 @10:25PM (#6028925)
    Congrats on what you've done so far...if you want to take the next step:

    Higher-quality ECGs systems don't use generic op-amps, they use special devices called instrumentation amplifiers that are able to reject common-mode signals at the inputs really well. Turns out then when you place electrodes on the skin, the skin between the electrodes acts like a crude battery (we're full of electrolyte after all!) and you get a large, shifting potential difference between the two electrodes that can drown out the millivolt-range ECG signal.

    Oh and by the way, the electrodes and wires will make great radio antennas (esp for 60 hz noise)! Check out the AD624AD instrumentation amp from Analog Devices.
    • Oh and by the way, the electrodes and wires will make great radio antennas (esp for 60 hz noise)!

      A few years ago I was undergoing a *HUGE* battery of tests at a London hospital to investigate potential Multiple Sclerosis. I had hours and hours of MRI (I loved that: just like being in a torpedo tube, I imagine, but VERY cosy), visual stimulation combined with extensive EEG studies, but the most interesting thing was the nerve conduction stuff.

      They stick electrodes into major nerves (upper arm, thigh, e
    • if you look at the schematic you will see that the designer has implemented the classic "instrumentation amplifer" (two non-inverting stages for high impedance, one inverter followed by a differential stage). The advantage of purchasing a single package "instrumentation amplifer" is that it saves tweaking. BTW if you build the authors circuit be sure and spend the extra pennies for 1% resitors it will work a whole lot better.
  • Polygraph (Score:4, Interesting)

    by po8 ( 187055 ) on Friday May 23, 2003 @10:25PM (#6028926)

    The ECG measurement is a key piece of the standard polygraph. One of these can be combined with a galvanometer (easy), a skin thermometer (easy), and possibly a respiratory rate measurement (harder: standard technique is to wrap the chest with a stress-sensitive band and build a circuit similar to the ECG one) for a lie detector that should be great fun at parties.

  • Malpractice (Score:5, Insightful)

    by b30w0lf ( 256235 ) on Friday May 23, 2003 @10:27PM (#6028936) Journal
    A disgustingly large amount of our medical expenses goes to malpractice insurance, and mostly to protect from one of the millions of malpractice cases that never should have been that occur each year. Granted, the ability to sue for malpratice *is* a good thing. However, it is grossly misused, and results in higher medical bills for all.

    Not to say that's the only factor... but that's one of them.
    • Re:Malpractice (Score:3, Insightful)

      by Davak ( 526912 )
      Poor little article on build-your-own-ECG has turned into why-medicine-is-expensive...

      Being a physician and having a friend who received a multi-million dollar settlement, I think I have a unique view of this.

      The problem started when MD's somehow got placed on a pedestal many years ago. People feel that doctors should know all the answers... well, we don't. There is still a lot of art in medicine... experience, knowledge, skill--all of these things are important.

      Doctors that practice _wrong_ medicine

    • On the oposite end of the spectrum is how infuriated I am with the Ohio state legislature for capping awards for malpractice and a rediculously low $750,000 even in cases of limb removal or permenant disability. My uncle was permenatly paralyzed when undergoing a routine back muscle surgery the doctor cut his spinal chord. You can't tell me that my 45 year old Phd uncle's complete loss of mobility and ability to make an income is only worth 3/4 of a million!
      • You can't tell me that my 45 year old Phd uncle's complete loss of mobility and ability to make an income is only worth 3/4 of a million!

        Indeed I can't. Your uncle's life and health are priceless to him and his loved ones.

        Unfortunately, your reasoning is flawed. If not for the unfortunate medical incident, your uncle could indeed go on and work another 20 years as a productive member of society, and retire a wealthy man. However, he might also win the lottery the very next day, and retire immediately

  • by FIRESTORM_v1 ( 567651 ) on Friday May 23, 2003 @10:28PM (#6028937) Homepage Journal
    ---^v---^v---^v-------

    Eeep...eep...eep..eeeeeeeeeeee

    time of death 927PM CST.
    Damnit jim I'm a doctor not a webserver admin..

  • looks like his server's monitor is flatlined :)
  • Welcome to my web page on how to make a simple ECG (electrocardiograph - also known as an EKG). Here you will find information how how to build one with less than $10 in parts. But before we get started, let's take a moment to talk about shop safety. Be sure to read, understand, and follow all of the safety rules that come with your power tools. Knowing how ....ummmmm, sorry. I guess I got into a little New Yankee Workshop [newyankee.com] moment there. :) Anyways, I do want to talk about safety. This device requires you to

  • Why It Costs So Much (Score:5, Informative)

    by istartedi ( 132515 ) on Friday May 23, 2003 @10:43PM (#6028987) Journal

    There are several reasons healthcare is so expensive.

    1. Litigation. Does the phrase "malpractice insurance crisis" ring a bell?

    2. A side effect of (1.) is something called "CYA medicine". Ever receive a chest CT because your heartburn just might be a pulmonary embolism? It happened to me just recently.

    3. Failed accountability. This one takes a bit more explaining. Ever bother to look at your bill? Of course not. Why? Because chances are, the insurance company pays it. Aha! You say. What if I'm not insured? Well then, many people who aren't insured "spend down" and go on Medicaid. Once more, nobody looks at what Medicaid is being billed, except for the hardworking beurocrats (cough)bull***(cough). Only the very narrow slice of the population that is "self paying" actually looks at a bill (more on thatlater) You would think that insurance companies would be on guard for their bottom line, but corporate inefficiency is often no better than government inefficiency.

    4. Complex and inefficient billing. Health care is one of the few businesses where you receive service at a single location, yet billing goes from subconractors directly to insurance companies or patients. Worse yet, billing from some contractors takes weeks, or even months. Yuck! Imagine if every business worked like this. Imagine getting your car fixed, and you get bills from the mechanic, the parts department, and the oil supplier spread out over 2 months. It's not just inconvenient. It actually hinders your ability to make financial plans because you don't know what's coming. And why don't you know what's coming? That leads us to...

    5. ...Secrecy. That's right. Secrecy. Try to call up a hospital and ask them for their price list. Chances are, you'll get the same answer I got: "That's on a computer and it's confidential". I was transferred to a manager who had her phone on voicemail. In retrospect, I should have known I was in trouble when the phone tree had "press 2 if you're an attorney". This is probably one of the biggest reasons healthcare costs too much. Sure, there are several hospitals within driving distance, but if I think I am going to need an exam that is likely to involve half an hour with a doctor, some medication, and an x-ray... I have no idea who charges the least for an x-ray, or what the hourly billing rate is for a doctor, or what the average examining time is for diagnosing a condtion. We have more accountability at the garage than we do at the hospital (Chilton's guides, posted labor rates, etc).This alone is probably the single biggest factor driving up healthcare costs. Lack of pricing information makes comparison impossible, resulting in a virtual monopoly even though there are multiple companies. So, what did I do? I gave up and paid a price that I could not verify as accurate because I knew that the only way to get the price list was to make a federal case out of it, and spend 100 times more in legal fees than my bill was.

    6. Vested interests. You can call me a conspiracy theorist if you like, but I think various interests want the price of healthcare to skyrocket so that they can use that as an excuse to socialize it. The corporations actually secretly like the idea of socialized medecine, because then they get to become government agencies. If you are a corporate sleazeball, the next step up is to become a government sleazeball; the perks are just that much better. You can just hear them salivating.

    Want to fix healthcare? Fine. Require providers to give one bill in a timely manner--no pass-throughs to subcontractors. Require providers to post price-lists online if they have a website, or to make price-lists available to the local libraries. Require employers who insure their employees to provider high deductable insurance. There should be no claims or forms until annual out-of-pocket costs exceed 10% of your annual pay. Place a cap punitive damages, as many have suggested.

    • 6. Vested interests. You can call me a conspiracy theorist if you like, but I think various interests want the price of healthcare to skyrocket so that they can use that as an excuse to socialize it. The corporations actually secretly like the idea of socialized medecine, because then they get to become government agencies. If you are a corporate sleazeball, the next step up is to become a government sleazeball; the perks are just that much better. You can just hear them salivating.

      You know, I agree with

    • billing from some contractors takes weeks, or even months.

      No lie, I recently recieved a bill for a consultation with an allergist (500$ for a 15 minute consulation!). I can't remember the exact date I went to the doctor, but I do remember I was a freshman in college, and the year had alot of 9's in it. There are no 9's in the date now, and I've been out of college (and unemployed) for a year :)

      Great post by the way

    • I'd just like to point out that medicine is *already* socialized.

      My late grandfather, Joseph F. Rudmin, was the first doctor in NY state to immunize all the kids in his district. But while he was county health commissioner, despite laws that said that only AMA members could hold government positions, he resigned the AMA.

      He did this, because the AMA was using his dues to lobby for laws that would reduce the number of doctors, in order to raise doctors' wages. In the end, the state AMA made him an honorar
  • by SuperBanana ( 662181 ) on Friday May 23, 2003 @10:44PM (#6028990)
    Makes me wonder why medical care costs so much

    Well, issues of "medical care" and "medical equipment" costs being two rather separate things(one of the biggest costs in medical care is liability insurance, probably followed by administrative overhead)...

    ...it might be because the expensive REAL version won't kill you when there's a lightning strike nearby, or when someone touches the case after building up a static charge, or something shorts out in the computer half...the list goes on. It only takes a few microamps to stop your heart- it's all in the path the current takes. Having those nice electrodes in the right places, making great electrical conduct with your skin...well, umm...you should get the picture.

    Medical equipment is designed to be 'bulletproof' in almost every way- there's a standard, for example, for medical-rated Edison plugs and sockets.(Edison plug = US electrical plug). It's VERY heavy duty, makes really good contact, has excellent stress relief on the cord, etc...because something VERY important might be using it, like an artificial heart pump in an operating room, or a dosage machine for an IV, or a ventilator. The REAL version also can't crash or stop working- so, for example, if it has a computer, the instruction code, the chips...everything is heavily tested. Jokes aside, the Pentium math dividing bug is a perfect example of why you can't just use "anything" for medical equipment. What if that bug caused the heart monitor to display the wrong heart beat rate? Electronics used for medical equipment get a LOT more testing- lives are at stake. Same idea behind the MIL specs, although with MILSPEC stuff, the idea is more that the military really abuses the crap out of stuff ON TOP of similar concerns as medical stuff.

    All of the above are why you often see these days disclaimers from chip makers that say "this device is not certified for use in life support equipment" and such. The statement often extends to industrial automation- "situations where malfunction may result in injury or death", stuff like that. Ie, "don't use this where if it screws up, it dumps 10 tons of molten steel on a bunch of steel workers' heads."

  • by Robber Baron ( 112304 ) on Friday May 23, 2003 @10:47PM (#6028999) Homepage


    That's the sound of yet another web server flatlining.


    BTW the only lame thing around here is your bloody "lameness" filters! How in hell else can I simulate a flatline in text without using repetition?

  • Mirror (Score:3, Informative)

    by KrispyKringle ( 672903 ) on Friday May 23, 2003 @11:17PM (#6029091)
    I'm sure if this weren't costing bandwidth, someone'd called me a karma-whore. That said, I'm attempting to wget a mirror to here [dnsalias.net].

    If you can, please mirror my mirror. I'm sure a large number of slashdot readers have servers available they can put to good use.

  • More leads would make this project more useful. Besides rate and rhythm, a real ECG machine is used to measure axis. Axis refers to the direction in which the heart depolarizes and repolarizes. Current ECG machines do rate, rhythm and axis computations automatically, but doctors are often suspicious of their findings. I think there is significant work left to make a more accurate and intelligent ECG.
  • The counter at the bottom of the page says:
    This site has been viewed: 11 times
    I think it's just a little bit off.
  • While he was researching his device, he should have looked a little harder at Einthovens work, and he would have seen where to actually place his electrodes (to get the tracing we all know, lead I). The way he has them in the photo explains the reason for his "negative deflection" They are in a place that looks at the Left anterior portion of the heart. Roughly V4 in medical parlance. This is an area where you want R wave progression, which is some of what he was seeing. I am sure some of it is his devi
  • You can get a safe (no pennies attached to a wire) useful (no need to attach yourself to big devices) heart rate monitor like Polar [polarusa.com] for 70$ so why would you want an EKG setup?
  • Medical care costs a lot because of the folks who think that government needs to provide every service to everybody.

    Back in the day (several old geezers I know have told me stories and they are all similar in this respect), if you had to have surgery done or whatever, you could "do business" with the doctor (bargain on price). Once the price was agreed, the service was carried out and you paid the doctor. That was simple. Then, a bunch of liberals came along and said, "Wait a minute. Some people can't affor

  • by cbnewman ( 106449 )
    <disclosure>I am a third year medical student at a state medical school in the United States</disclosure>

    This is a multifactoral problem. The average medical student graduates with about $180,000 debt (closer to $220,000 by the time it's paid off). Monthly payments can be about $1,000 per month.

    Secondly, technology has largely supplanted physical diagnosis. Doctors have gotten sloppy in the past due to reliance on expensive diagnostic tests rather than relying on patient's history and their 5
    • by StandardCell ( 589682 ) on Friday May 23, 2003 @11:52PM (#6029195)
      I have always said that if engineering were practiced like medicine is practiced by doctors, people would be dead. Gone due to a bridge or building falling down, or electrocution, or a chemical plant exploding because they rely on what they've seen before rather than what the problem might really be.

      Real engineers are thorough thinkers. That is the most fundamental skill one is supposed to learn in engineering. Engineers should think about what the real root cause of the problem is and every possible answer to the problem. While cost is a consideration, an engineer will tell it like it is and tell you that you have to choose between something that works and something that costs what you want it to cost.

      Doctors, on the other hand...well, I've gone to doctors telling them that I can't sleep and the first thing they do is want to pump me full of Xanax. They never asked me if there was something wrong going on personally in my life, or if I'm consuming too much caffeine or MSG, or anything. Just wanted to prescribe crap and get me out of their office. Fortunately, I told the doctor I wasn't taking Xanax and promptly found another doctor who sorted it out (too much caffeine). These are the same idiots who prescribe Ritalin to kids who won't behave in class because their parents are too busy stuffing them full of sodas.

      But that's my point. As an engineer, it's my job both to identify the root cause of the problem and investigate the most feasible solution. I will never sign off on an engineering document if I feel someone will be in danger, including my reputation. Piss-poor engineers (and, unfortunately, your average doctor) will let it go through. So please, don't make that comparison, because it's patently ridiculous.
  • Safety whiners. (Score:2, Interesting)

    by acceleriter ( 231439 )
    I don't know what everyone's one about. I just built one of these. I'm monitoring my heart rate in a window right now and it works gr9'0wrtup
  • From the article:
    "but don't come crying to me if you find yourself dead."

    You also see dead people?
  • by El Puerco Loco ( 31491 ) on Friday May 23, 2003 @11:51PM (#6029191)
    There was something like this in Scientific American a while ago, only it used an instrumentation amplifier instead of an op-amp, which would reduce common mode interference and give you a cleaner signal. Analog Devices makes a cheap one, AD620 which sells for around $5 and wouldn't raise the cost of the project too much. They also make an expensive one, AD624AD, around $20 with better gain and better common mode rejection, still not outrageously expensive. some diodes to give some protection against getting electrocuted by a power surge might be a good idea too, for those girly men who can't handle their electricity. you can buy real ekg electrodes cheap too. Of course, you'll blow your entire budget hiring a cardiologist to interpret the results.
  • then for capital punishment why bother with an electric chair with hundreds of volts and significant amerage? Why not just use a 12-volt car battery and a little gel? A Die-Hard perhaps?
  • by Anonymous Coward
    Scientific American published such a circuit in their Amateur scientist area a few years ago... link to article [sciam.com].

    It is a commonly referenced site.
  • by Pettifogger ( 651170 ) on Saturday May 24, 2003 @12:26AM (#6029298)
    Speaking of medical safety...did anyone notice that this device is running under Windows? I don't know about you, but I'd never hook anything running Windows up to my body.
  • when slashdot posts a story about something one is very familiar with, you really get to see what a bunch of liars are make posts.
    The amount of people claiming to know this stuff that are absolutly wrong in there posts mean, they are liars, OR there going to kill someone with there incompetence.

  • Medical Costs (Score:4, Interesting)

    by Arandir ( 19206 ) on Saturday May 24, 2003 @02:42AM (#6029726) Homepage Journal
    Makes me wonder why medical care costs so much.

    Although I will agree that medical costs are high, it's not due to the costs of the parts used to build ECG machines. Geez!

    You would trust your diagnosis to a $4 machine built by some hobbyist on the weekend? I sure as well wouldn't. But even if the parts for a real ECG cost $400, it still doesn't demonstrate why you can't buy one for $400. So let me explain why it costs so much more: the price of ECGs has nothing to do with the price of its parts. Price is subject to the buyer's and seller's wants. If the price is too low the seller won't sell. If it's too high the buyer won't buy. If you've just spent two years developing a new ECG machine involving the work of a couple dozen engineers, testers, clinicians and marketroids, and hammered it out in clinical trials, fenced with the FDA, and met all the spurious checkboxes of the bureaucracies, you want some return on your investement. If you manage to sell only 50,000 then $400 a pop isn't going to cut it! (do the math) On the other hand, if you're a hospital with an increasingly shrinking budget and overseen by a hospital board composed of well-meaning but ignorant politicians, then $40,000 isn't going to cut it either. So a price is eventually reached that is mutually acceptable. It's going to be a lot higher than the price *you* would have paid, but you're not a hospital.

    Why don't you get any input into the price? After all, you're the patient, and thus indirectly the buyer. The reason is that you have absolved yourself of any buyer responsibilities by foisting them off on an insurance company. If everyone who had an ECG reading had to pay for them out of their own pockets, you damn well better believe the price will come down! One reason medical prices are high because people (you, your employer, etc) don't shop for medical prices, they shop for monthly payments to an insurance company instead.

    But ignore what I just said. I'll tell you what the real price of ECGs is. Free. Zero dollars and zero cents. You see, when a company like Siemens, Philips or GE makes a sale to a hospital, they throw in the ECG (and lightbulbs) for free. I may still cost those companies $500 in parts and $5,000,000 in R&D, but they'll make it up on the MRI, CAT, and US. And of course, on the service plans.
  • by blair1q ( 305137 ) on Saturday May 24, 2003 @03:14AM (#6029788) Journal
    Econ 101.

    Inelastic pricing.

    You pay whatever we ask, or you die, or lie there in pain and fear.

    Oh, and we'll pretend we have these standards for quality of drugs and equipment and caregivers, but that's just to forestall liability. This stuff is just as crappy as the stuff you buy at Walgreens, and these people are just as incompetent as the people who work at Walgreens.

    And half of it is padding and sandbagging because you're too ignorant to know that you don't use a rheostat in a colonoscopy.

    And we have all the money now, so we own the votes we need to stop you whenever you try to change the system by changing the law.

    Now. Back to the price.
  • by hugesmile ( 587771 ) on Saturday May 24, 2003 @08:51AM (#6030345)
    If you try this at home, please document your efforts at this site [darwinawards.com].

"Here's something to think about: How come you never see a headline like `Psychic Wins Lottery.'" -- Comedian Jay Leno

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