9 ms·

Alarms in medical equipment

185 points by gaudat 2y ago

odiroot 2y ago
I was looking for some good notification sounds for my ESP Home's buzzer. These are a great inspiration.
bouvin 2y ago
Fascinating. Interesting to hear the differentiation in severity in the same class of error. Though a bit disappointing that there is no machine that goes PING! [1] [1] https://youtu.be/VQPIdZvoV4g?si=Ov4AuyKgeKtmYmz9 https://youtu.be/VQPIdZvoV4g?si=Ov4AuyKgeKtmYmz9
LorenPechtel 2y ago
And how about the fact that there are simply too many of them! I was once in the recovery room with my wife. For some reason the sensor was having a very hard time reading her pulse. The normal bips would frequently fail. Too many failures in a row and the alarm would start it's EEEEEE scream we've all seen from Hollywood. It would shut up as soon as it managed to pick up a beat. Hers was definitely not the only one in the room occasionally screaming. The nurses were completely ignoring it. Quite understandably so as it was obviously doing false alarms. But in a flood of false alarms like that are the real ones going to be noticed??
- jandrese 2y ago
  False positives are definitely a problem. When you read industrial accident reports one extremely common theme is some sensor that was notifying the controller of the problem, but that sensor had a history of false positives so it was disregarded. Companies that don't take false positives seriously are inherently dangerous.
  - teeray 2y ago
    Many of those companies fall into the trap of “well, we’d rather a noisy alarm that catches the problem than a silent one that doesn’t.” Both are problems. The former just makes management feel like a problem would be caught be the on-call.
    - throwaway173738 2y ago
      The ventilator company I worked for tried very hard to avoid false positives because we were very concerned about alarm fatigue. We also tried to ride the line on false negatives. It’s really hard. Sometimes the alarm limits are set incorrectly by the RT or aren’t forgiving enough to allow some motion. When you see an entire ward of nurses totally ignoring alarms it’s a management failure. Either there aren’t enough nurses available to manage the issue or there aren’t enough technicians to properly configure the equipment for each patient. If someone dies because of that then it’s ultimately the hospital’s fault.
      - LorenPechtel 2y ago
        The day I encountered it I have no idea of what sensitivity controls might have existed but the problem was unquestionably the system failing to recognize that what had just transpired was a beat. The trace on the screen looked like a beat to me, but not always to it. I will not say it was a management failure because I don't know if management could have done anything about it. Given the total indifference of the nurses I strongly suspect they couldn't do anything.
    - makeitdouble 2y ago
      Management could be the most relevant part. A silent alarm is management's fault, a wrongly ignored noisy alarm can be pushed as staff's fault.
      - heavenlyblue 2y ago
        Pretty certain management have 0 control over which alarms can be disabled on the equipment. And I would bet that the equipment from other brands have the same issue.
  - kelnos 2y ago
    > Companies that don't take false positives seriously are inherently dangerous. Alarms with incessant false positives are inherently dangerous. Sure, there's some threshold of false positives, under which we should still expect people to investigate all alarms. But above that threshold, how can we continue to blame the people involved? The hardware is at fault.
    - pjerem 2y ago
      I think GP was talking about the people who don’t try to reduce false positives (by actively searching for solutions to reduce them), not the ones ignoring them because they are used to.
    - nradov 2y ago
      Please propose a design for better hardware then. You'll make a fortune and do a lot of good in the process. Seriously, what would motivate you to make a comment like that? Do you think medical device engineers and clinicians are unaware of the false alarm issue and haven't already tried a variety of improvements? There is an inherent trade-off between false alarms and missing a real problem. And devices need to be not only accurate but also affordable, durable, and cost effective. It's not easy to get this right.
  - kmoser 2y ago
    It's hard to solve the problem of false positives when the decision to sound an alarm is reliant on a single sensor that may start to become detached (e.g. glue/tape failure). If you think the solution is multiple sensors, well, what happens when one sensor indicates an alarm condition and the other doesn't? Now you have another potential false positive. Not to mention it's untenable to connect twice as many leads to a patient.
    - bee_rider 2y ago
      If they’d use three sensors, they could vote. If one sensor often votes differently from the other two, it could be marked as defective and replaced or re-seated. Three times as many leads would be pretty annoying, though.
      - lostlogin 2y ago
        You’ve hit the nail on the head. It’s often tedious getting one to work.
    - LorenPechtel 2y ago
      That could partially be addressed by making the sensor include the concept of not working. Run a small electric current across the sensor, if that current fails the sensor knows that it's not monitoring and can report it as a loose sensor rather than as a failure of whatever it's supposed to be sensing.
  - krisoft 2y ago
    > When you read industrial accident reports one extremely common theme is some sensor that was notifying the controller of the problem, but … I remember an accident report. It was about a container ship which had a bad flooding incident in their engineering spaces. One thing the report pointed out that the engineers had ways to fight the flooding, but they were not doing them because they were playing whack-a-mole with all the alarms caused by the flood. If i recall correctly the engineers kept ignoring the waist deep and rising water and prioritised silencing the alarms. (And not because they were stupid, but just because the many independent blaring alarms task-saturated them.)
    - Johnny555 2y ago
      they were playing whack-a-mole with all the alarms caused by the flood That's common in computer monitoring systems, at my last job when we had a serious outage, we'd get dozens of pager alerts, it was hard to figure out the root cause because so many alerts fired that were caused by the root cause. I.e. like if the root cause was a root volume was out of disk space, the "unable to log in" alert was superfluous and not helpful. Eventually we moved to a better system that had a betrer sense of hierarchy for alerts as well as a way to easily silence them.
- ler_ 2y ago
  Knowing how to trend the patient's health is probably more useful than relying on all the alarms. People hardly deteriorate from one second to the next if you know what to expect from their baseline. At least that's what I did when working as a nurse. However, I never worked in some place like the ICU, so the approach might be different in that case.
- btach 2y ago
  Anecdote: At an ED I used to work at, our cardiac monitors got "upgraded" to another manufacturer. Silencing false alarms was a black hole of a game of whack-a-mole. You could never silence them all, another would just pop up to spite you. Anyway, one night, it was continuing to alarm and being ignored (with a glance occasionally to make sure). Except somebody was in v-tach and the person who noticed was a medic bringing a patient in. Thank goodness they noticed amid the noise! (We had as good of outcome as could be expected with that patient, and they went to the cath lab and lived).
  - dmurray 2y ago
    What would have happened if the medic didn't notice and the patient died? Would you have got the blame for ignoring it, or management for creating a situation where you had no choice but to ignore some alarms because of false positives, or the manufacturer, or would it have been swept under the rug as "the patient was having heart failure and unfortunately even our state-of-the-art medical care couldn't save him"? All of those sound superficially plausible to me, although I have my ideas on which are more likely... Would you even do an, um, incident post mortem for something like that or would it just be a statistic?
    - btach 2y ago
      There would definitely be an investigation, as all sentinel events are investigated. Management would do their RCA and I'm sure the issue with alarm fatigue would be ignored or underplayed (Something bad happen? make sure an alarm sounded. If staff ignored it, it must be the fault of the staff). I doubt any one person would be in trouble as it was a collective/systemic failure, but I don't know exactly what would have come of it. Likely a policy change or daily reminders for the next few weeks about not ignoring the monitors even if it has been going off nonstop for hours. Maybe extra charting or peer audits. It's a lot less expensive and effort to put pressure on staff than it is to change technology (even if it is as little as setting different, more sane, defaults). Depending on what was recorded from the monitor to the chart, if it looked like there wasn't a delay in resuscitation/cardioversion (like if the lethal rhythm wasn't recorded initially), it may have been just put down as clinical course for the patient, like you suggested. My perspective of that place is a bit jaded (and therefore biased), that place was a toxic burn-out factory. BTW, "post mortem"? Thanks, the morbid humor made me laugh!
- _yb2s 2y ago
  Hospitals have a sort of manic "New York Stock Exchange" energy and environment to them... The entire environment of a modern hospital seems brutally incompatible with the type of peaceful relaxing environment you'd want to reduce stress and improve patient outcomes. Bright lights, constant noise, loud electronics, preventing patients from sleeping based on whatever schedule is convenient to medical staff, etc. I think they could substantially improve patient outcomes by taking some tips from the best modern birthing centers, and make a quiet, relaxing, dimly lit, and peaceful environment at hospitals. I'd also say add some plants, natural (wood) surfaces and natural light, but realize that might make it hard to keep things sterile and private. It would make sense to create a rough schedule for each patient also with a consistent "left alone unless there is an emergency" time for sleep, etc. I would imagine a calm and quiet physical environment would also reduce stress, fatigue, and improve performance of the medical staff themselves.
  - Aeolun 2y ago
    Don’t think it’s so unrealistic to make a sterile green environment with fake plants. Fairly certain it doesn’t matter too much.
  - nradov 2y ago
    You're not wrong. ICU delirium is a serious problem. https://www.statnews.com/2016/10/14/icu-delirium-hospitals/ https://www.statnews.com/2016/10/14/icu-delirium-hospitals/ But it's tough to make improvements. Regular hospital design is (roughly) optimized for staff productivity. They need to be able to treat and monitor many patients simultaneously which requires clear sight lines, good lighting, and a high level of automation. A more humane hospital design would also require more staff at a time when we already have a severe shortage. Where would the funding come from?
  - matheusmoreira 2y ago
    Hospitals are not "peaceful relaxing environments". They are large scale industrial operations designed to process as many people as possible. There simply aren't enough resources to afford every single person a "relaxing environment". You do the best you can for as many as you can. All this "relaxation" stuff will quickly be converted into spare capacity the second large numbers of severely wounded people start showing up at the emergency room. If you're a multibillionaire then obviously you can just hire and equip your own private medical team that will focus 100% of their attention and care exclusively on you and your needs. The vast majority of the humans will never have that luxury. Normal people enter the system and are processed like everyone else.
- Buttons840 2y ago
  There will always be false positives and false negatives, they have to be balanced. If the cost of a actual negative is 100 and the cost of an actual positive is 1. You'd expect there to be approximately 100 times more false negatives, because we want to be 100 times more sensitive to the costly negative condition. I'm this sense, the alarms in hospitals make sense. Actual negative are very costly. But this is a cold mathematical analysis that doesn't consider alarm fatigue and the cost of people learning to ignore the alarm. I wonder how to best model human nature in this calculation? An optimal solution would require considering all alarms, and modeling the fact that every alarm given is another alarm ignored (assuming the hospital is operating at capacity, if it's below capacity the solution is easy, just manually check all alarms). This system might realize that the 4th "no pulse" alarm of the night for Alice would detract from the 1st "no pulse" alarm for Bob, and that Bob's is more likely to need attention. I'd be terrified to program such a system though, and from what I've seen in corporate programming environments, I'm not confident any company could get this right.
  - LorenPechtel 2y ago
    You have it backwards. They really do not want false negatives because that gets them sued. Thus the system will be set up to err on the side of false positives--the current liability climate does not blame them for alarm fatigue. Consider a local case (although it's possible it was overturned on appeal): Yes, the doctor was unquestionably playing loose with standard safety precautions. His behavior transmitted blood-borne infections. He died in prison which was well deserved. However, the lawyers went hunting for some deep pockets. The manufacturer of the drug involved in the cross contamination. They made various size vials, including some that were bigger than would be used on one patient. This permitted the doctor to contaminate between patients and got them hit with a $250M verdict. (Never mind that had they truly only used clean needles with them like they should have there never would have been an issue. They used a new needle but the old syringe.) That's the sort of insane legal pressure driving the garbage.
- takinola 2y ago
  I used to work as a field engineer on oilfields and rigs. We had panels of equipment, each with their own alarms and beeps. Once the rig manager (the client) remarked that we were ignoring the alarms, snidely insinuating that we should pay more attention given the possibility of things going wrong. The reality was we knew what was going on just by listening to the alarms. I could predict which alarm was going to go off before it did and so I could safely (appear to) ignore them. I would only panic if an unexpected alarm went off (or happened in an unexpected sequence). It is possible the same situation was going on in the hospital.
  - KennyBlanken 2y ago
    Nope. Alarm fatigue is a well documented problem in the medical field. Like residents who are getting a few hours of sleep over days worth of high-stress / high-stakes work, poor hand-washing between patients, and not clearly printing one's handwriting on prescription forms - all things that kill patients - doctors and hospital administrators just don't care enough. For a profession that is supposedly so pure morality-wise - do no harm, patient privacy, etc - doctors are remarkably careless.
    - hiAndrewQuinn 2y ago
      "They just didn't care enough" is an argument which can explain everything about how 1 person operates, half of a 10 person group, and roughly 0% of an entire profession. It's a question of the economic incentives at play far more than doctors universally deciding not to give a shit. The economic recommendation is to deregulate the medical personnel industry and allow supply to increase. A great many smart and good people would love to become doctors but aren't in love with 5 years of residency and taking a quarter million dollars in debt to make less than their dropout cousin does at Netflix.
      - nabusman 2y ago
        Pure deregulation can lead to a bit of anarchy, but a more measured approach that ensures that the regulation doesn't act as a way to decrease supply and increase profits for the industry would make sense. Probably something for Lina Khan to look into.
- deanresin 2y ago
  My Mom recently had brain surgery and was recovering. Her machine would go off all the time and it took forever for a nurse to come buy and fiddle with it. I would joke to my Mom that it probably meant she was dying. Those beeps were so annoying. If anything, they should be beeping in the nurse's control area. It seems ridiculous it has to beep loud enough for a nurse down the hallway to hear it when it never seemed to be anything urgent or dangerous. Certainly, no one came running.
tux3 2y ago
Trying to figure out which melody was which in an emergency doesn't seem like the most human-friendly. Contrast with the GPWS warnings in aviation, which tells you what the problem is (TERRAIN TERRAIN) and what to do (PULL UP) in a progressively more alarmed voice as things get worse. (Well.. Sometimes you hear of some particularly bright individuals who think the bank angle warning is a checklist item, but it's generally hard to get these wrong, compared to many other beeping warnings)
- sebmellen 2y ago
  GPWS warnings should be the gold standard for any sort of urgent audio alarm. Examples: https://www.youtube.com/watch?v=W5Z-d1Zx02o https://www.youtube.com/watch?v=W5Z-d1Zx02o
  - imglorp 2y ago
    At :42 I think the buzzing sound is the "stick shaker" stall warning. It literally shakes the pilot's control yoke. So not only is it an alarm, it's also reminding the pilot of the correction needed: to push the control forward.
    - varjag 2y ago
      Wouldn't that be pull backward?
      - seabass-labrax 2y ago
        Not in this case, because the 'stick shaker' activates when the aircraft is stalling or close to stalling. The only sensible option in this scenario is to lower the angle of attack, that is, pitch forward. If you have both the GPWS 'terrain, pull up' warning and the stick shaker warning simultaneously then you are in a sticky situation indeed.
        krisoft 2y ago
        > If you have both the GPWS 'terrain, pull up' warning and the stick shaker warning simultaneously then you are in a sticky situation indeed. Yeah. To quote the movie Wargames: “The only winning move is not to play.” That is a pilot should do their best to avoid getting into anywhere near that situation.
g15jv2dp 2y ago
What's not clear from this webpage is whether these are actually used anywhere. Are they? I couldn't tell.
- thomasthorpe 2y ago
  Yes, well, some. To gain certification, often something customers require, medical devices must comply with standards such as ISO60601 (hardware) ISO62304 (software) and ISO13485 (process, quality management). The alarm waveforms described are within the scope of the hardware standard guidelines, sufficiently common that application notes such as this exist. https://www.ti.com/lit/pdf/slaaec3 https://www.ti.com/lit/pdf/slaaec3 [ti.com]
  - HeyLaughingBoy 2y ago
    > often something customers require A bit more than that. Certification is required in order to put your product on the market. Whether or not customers require it is irrelevant.
davidw 2y ago
It gives me anxiety just looking at this. Add this to the list of things I don't want to work on.
- HeyLaughingBoy 2y ago
  On the producing or consuming side? FWIW, I found the article interesting as I'm starting a new Oxygenator project so I'm probably about to become even more familiar with IEC60601 :-(
  - davidw 2y ago
    I don't want to work on software where bugs might cost someone their life.
    - HeyLaughingBoy 2y ago
      I get that, but it's very unlikely to happen. The benefit of your code vastly outweighs the potential downside. As engineers, we're used to only hearing about the problems. It's really gratifying when you hear from someone who says, "tell your engineers that they saved my life."
blackeyeblitzar 2y ago
I absolutely hate the poor design of medical equipment found in hospitals. The worst thing by far is the constant beeping and noises in the room, which totally disrupts rest and hurts recovery. It is SO obvious that this hurts patients (and visitors), that I cannot believe the entire medical industry (nurses, doctors, hospital administrators, equipment makers, insurance companies) have failed to do anything about it. It also makes it hard to know if some sound is expected or if it is a signal that something is wrong. In addition to this, I’ve seen nurses make mistakes several times because the equipment is too confusing. Once, I had to page the nurse myself because the IV they thought they set up was not functioning and I was able to discern that from the screen on the IV machine (which said one particular drug was not active) but they had not noticed, essentially administering an imbalanced cocktail of drugs for a period of time. My take - the medical industry has too many barriers to competition, and it is too difficult for people who work with these things to do anything about it as well. It’s unclear who the buyers are at a hospital or how a startup could reach them. It’s also unclear what sort of interoperability (for example with Epic for charting) is needed. Regulations also make it difficult to get devices approved and investors are less likely to support a startup in this space.
- atahanacar 2y ago
  >I’ve seen nurses make mistakes several times because the equipment is too confusing. Once, I had to page the nurse myself because the IV they thought they set up was not functioning and I was able to discern that from the screen on the IV machine (which said one particular drug was not active) but they had not noticed This doesn't sound like the equipment's fault.
  - blackeyeblitzar 2y ago
    Technically no, but watching them debug it and configure it made me think it’s too complicated. They basically had to figure out the right sequence of buttons to hit.
- mschuster91 2y ago
  It's a necessity, a side-product of not having anywhere near enough nurses, assistant staff and doctors in hospitals. They're juggling alarms constantly (which have to blare in a cacophony) and speed from one patient to the next. Ideally you'd have a 1:1 (or better!) assignment between a single patient to a single nurse in critical care, 1:3 for patients that can't move around on their own (and thus need more assistance, even if it's just helping them to eat or go to the loo), and 1:5 to 1:10 for everyone else. The sad reality is that even in Germany, you have care home staff calling in the fire department to assist because there were just three staff in a night shift, having to deal with 170 patients. [1] https://www.morgenpost.de/berlin/article242110812/Kurioser-Grund-Feuerwehr-Polizei-ruecken-in-Seniorenheim-an.html https://www.morgenpost.de/berlin/article242110812/Kurioser-G...
ano-ther 2y ago
I seem to remember that some of these sounds (perhaps the one with syllables) were originally part of a joke paper and that the author was quite astonished how they became part of a standard. Unfortunately, I cannot find the article anymore.
tverbeure 2y ago
A friend of mine used to have a small side business selling loudspeakers for medical equipment. She order them in Asia and had her own little certification lab at home: heat chamber, impedance testing, that kind of stuff. Every so often, she’d receive an order of a few hundred speaker, and test them one by one. It’s a low volume but high margin business. Some of the issues were the constant fight against the factory not following design requirements to cut costs, knockoffs etc.
roughly 2y ago
The cardiac alarm tone is unexpectedly jaunty.
- graypegg 2y ago
  Out of all of them, it’s definitely the most “washing machine is done”
strnisa 2y ago
The standardization of medical alarms was important when introduced, providing consistent and clear communication across devices and countries. However, with modern technology, these standards may now limit innovation. It seems to me that clear verbal alerts like "BLOOD PRESSURE VERY HIGH" could be more immediately understandable than tones. A hybrid system combining verbal alerts with alarm tones might be a good compromise for clarity and international usability.
- ncallaway 2y ago
  I don’t know, I kinda think if you’re going to have verbal warnings you kinda need a centralized system that processes all alarms to triage them like in an airplane. If even 2 verbal alarms are going at the same time, it’s going to create a chaotic environment. In a decentralized system, I think tones have less of an overlapping problem.
  - Aeolun 2y ago
    If two of these tones sound at the same time, I’m fairly certain I couldn’t distinguish them.
throw46365 2y ago
I remember my Dad, in his last day conscious, with a fluid line in that kicked off some sort of pressure alert every time he raised his hand to his face… which he did compulsively because of his confusion on top of his dementia. The nurses obviously couldn’t respond to it each time, but nor could they switch it off altogether, and it didn’t reset after any period of time. My siblings and I took turns to gently hold his arm down on the side of the bed… which became just holding his hand, which I still miss.
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ijustlovemath 2y ago
We're building a life critical medical device, and I haven't seen this mentioned, so I thought it was worth contributing: The use of these alarms is not something imposed by the manufacturers, but by the standards, eg 60601, 62304 etc. For devices involved in diagnostic, or more importantly interventional care, you are required to have alarms within certain auditory and visual thresholds, and a lot of them have mandated silence times (in a life critical system, you can only silence a true alarm for 120 seconds at a time). Then again, "ALARM" as dictated by the standards means something truly emergent, though the wording can feel a bit fuzzy at times. Trust me, alarm fatigue is a known phenomenon to these manufacturers, and theres been a recent trend (with, eg, the Dexcom G7) of giving users more control over delaying alarms, silencing them until you can respond etc etc, which has its benefits, especially as quality of life is concerned. You'll have a hard time convincing the FDA of this for critical devices like those found in hospitals though.
- jimmySixDOF 2y ago
  The airline industry went through this too and have moderated requirements to be more understanding of who it's consumers are and when. One of the big near miss cases was QF32 out of Singapore where they had over 50 alarms to deal with in addition the the emergency at hand. Alarm pollution is a real UI/UX dilemma.
  - hejdufufjrj 2y ago
    In an airplane at least all the alarms are integrated, but in a hospital room you'll have 15 devices from 7 manufacturers spanning 5 generations.
  - amelius 2y ago
    Maybe someone can train an AI to decide which alarms need immediate attention, given N staff members available.
    - throwaway765123 2y ago
      Yikes I hope this is tongue-in-cheek, I definitely don't want a statistical process deciding whether to surface a life-critical alarm to healthcare staff
userbinator 2y ago
Some of them remind me of YouTuber Ashens' intro sound.
jill4545 2y ago
An amendment to IEC 60601-1-8 introduces the concept of acoustic icons. These are the alarms that mimic the sound of what the device does e.g. a ventilator would be a sighing/breathing sound as well as a pulse to indicate if its alarm with a priority. This directs the clinician to know immediately which device is alarming and how high the priority is as opposed to a plethora of beeps and pings all merging together. Could be a game changer.
kioleanu 2y ago
Only very slightly tangential, I remember when my son had his surgery and had to be in the hospital, they would have these dosing machines for the medicine and they would start throwing a warning sign 3 minutes before the syringe was empty, every 30 seconds and then a proper alarm when it was empty. Now, we were supposed to call a nurse to remove the syringe, and each nurse had their own preference on when to be called. Some said call us when the warning starts, some said call us a minute before and some said call us when the red alarm goes off. We found this strange until one of them explained it is simply related to the amount of chit chat they wanted to do with us, as the syringe always had to go out at the red alarm
Shawkam1234 2y ago
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chess_buster 2y ago
There's a dissertation from a Professor of Health Care about Alarms in ICUs: https://uol.de/f/2/dept/informatik/download/Promotionen/Cobus_Diss.pdf https://uol.de/f/2/dept/informatik/download/Promotionen/Cobu...
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imadoctor 2y ago
[flagged]

185 points by gaudat 2y ago

I was looking for some good notification sounds for my ESP Home's buzzer. These are a great inspiration.

Fascinating. Interesting to hear the differentiation in severity in the same class of error. Though a bit disappointing that there is no machine that goes PING! [1] [1] https://youtu.be/VQPIdZvoV4g?si=Ov4AuyKgeKtmYmz9 https://youtu.be/VQPIdZvoV4g?si=Ov4AuyKgeKtmYmz9

LorenPechtel 2y ago

And how about the fact that there are simply too many of them! I was once in the recovery room with my wife. For some reason the sensor was having a very hard time reading her pulse. The normal bips would frequently fail. Too many failures in a row and the alarm would start it's EEEEEE scream we've all seen from Hollywood. It would shut up as soon as it managed to pick up a beat. Hers was definitely not the only one in the room occasionally screaming. The nurses were completely ignoring it. Quite understandably so as it was obviously doing false alarms. But in a flood of false alarms like that are the real ones going to be noticed??

jandrese 2y ago
False positives are definitely a problem. When you read industrial accident reports one extremely common theme is some sensor that was notifying the controller of the problem, but that sensor had a history of false positives so it was disregarded. Companies that don't take false positives seriously are inherently dangerous.
- teeray 2y ago
  Many of those companies fall into the trap of “well, we’d rather a noisy alarm that catches the problem than a silent one that doesn’t.” Both are problems. The former just makes management feel like a problem would be caught be the on-call.
  - throwaway173738 2y ago
    The ventilator company I worked for tried very hard to avoid false positives because we were very concerned about alarm fatigue. We also tried to ride the line on false negatives. It’s really hard. Sometimes the alarm limits are set incorrectly by the RT or aren’t forgiving enough to allow some motion. When you see an entire ward of nurses totally ignoring alarms it’s a management failure. Either there aren’t enough nurses available to manage the issue or there aren’t enough technicians to properly configure the equipment for each patient. If someone dies because of that then it’s ultimately the hospital’s fault.
    - LorenPechtel 2y ago
      The day I encountered it I have no idea of what sensitivity controls might have existed but the problem was unquestionably the system failing to recognize that what had just transpired was a beat. The trace on the screen looked like a beat to me, but not always to it. I will not say it was a management failure because I don't know if management could have done anything about it. Given the total indifference of the nurses I strongly suspect they couldn't do anything.
  - makeitdouble 2y ago
    Management could be the most relevant part. A silent alarm is management's fault, a wrongly ignored noisy alarm can be pushed as staff's fault.
    - heavenlyblue 2y ago
      Pretty certain management have 0 control over which alarms can be disabled on the equipment. And I would bet that the equipment from other brands have the same issue.
- kelnos 2y ago
  > Companies that don't take false positives seriously are inherently dangerous. Alarms with incessant false positives are inherently dangerous. Sure, there's some threshold of false positives, under which we should still expect people to investigate all alarms. But above that threshold, how can we continue to blame the people involved? The hardware is at fault.
  - pjerem 2y ago
    I think GP was talking about the people who don’t try to reduce false positives (by actively searching for solutions to reduce them), not the ones ignoring them because they are used to.
  - nradov 2y ago
    Please propose a design for better hardware then. You'll make a fortune and do a lot of good in the process. Seriously, what would motivate you to make a comment like that? Do you think medical device engineers and clinicians are unaware of the false alarm issue and haven't already tried a variety of improvements? There is an inherent trade-off between false alarms and missing a real problem. And devices need to be not only accurate but also affordable, durable, and cost effective. It's not easy to get this right.
- kmoser 2y ago
  It's hard to solve the problem of false positives when the decision to sound an alarm is reliant on a single sensor that may start to become detached (e.g. glue/tape failure). If you think the solution is multiple sensors, well, what happens when one sensor indicates an alarm condition and the other doesn't? Now you have another potential false positive. Not to mention it's untenable to connect twice as many leads to a patient.
  - bee_rider 2y ago
    If they’d use three sensors, they could vote. If one sensor often votes differently from the other two, it could be marked as defective and replaced or re-seated. Three times as many leads would be pretty annoying, though.
    - lostlogin 2y ago
      You’ve hit the nail on the head. It’s often tedious getting one to work.
  - LorenPechtel 2y ago
    That could partially be addressed by making the sensor include the concept of not working. Run a small electric current across the sensor, if that current fails the sensor knows that it's not monitoring and can report it as a loose sensor rather than as a failure of whatever it's supposed to be sensing.
- krisoft 2y ago
  > When you read industrial accident reports one extremely common theme is some sensor that was notifying the controller of the problem, but … I remember an accident report. It was about a container ship which had a bad flooding incident in their engineering spaces. One thing the report pointed out that the engineers had ways to fight the flooding, but they were not doing them because they were playing whack-a-mole with all the alarms caused by the flood. If i recall correctly the engineers kept ignoring the waist deep and rising water and prioritised silencing the alarms. (And not because they were stupid, but just because the many independent blaring alarms task-saturated them.)
  - Johnny555 2y ago
    they were playing whack-a-mole with all the alarms caused by the flood That's common in computer monitoring systems, at my last job when we had a serious outage, we'd get dozens of pager alerts, it was hard to figure out the root cause because so many alerts fired that were caused by the root cause. I.e. like if the root cause was a root volume was out of disk space, the "unable to log in" alert was superfluous and not helpful. Eventually we moved to a better system that had a betrer sense of hierarchy for alerts as well as a way to easily silence them.
ler_ 2y ago
Knowing how to trend the patient's health is probably more useful than relying on all the alarms. People hardly deteriorate from one second to the next if you know what to expect from their baseline. At least that's what I did when working as a nurse. However, I never worked in some place like the ICU, so the approach might be different in that case.
btach 2y ago
Anecdote: At an ED I used to work at, our cardiac monitors got "upgraded" to another manufacturer. Silencing false alarms was a black hole of a game of whack-a-mole. You could never silence them all, another would just pop up to spite you. Anyway, one night, it was continuing to alarm and being ignored (with a glance occasionally to make sure). Except somebody was in v-tach and the person who noticed was a medic bringing a patient in. Thank goodness they noticed amid the noise! (We had as good of outcome as could be expected with that patient, and they went to the cath lab and lived).
- dmurray 2y ago
  What would have happened if the medic didn't notice and the patient died? Would you have got the blame for ignoring it, or management for creating a situation where you had no choice but to ignore some alarms because of false positives, or the manufacturer, or would it have been swept under the rug as "the patient was having heart failure and unfortunately even our state-of-the-art medical care couldn't save him"? All of those sound superficially plausible to me, although I have my ideas on which are more likely... Would you even do an, um, incident post mortem for something like that or would it just be a statistic?
  - btach 2y ago
    There would definitely be an investigation, as all sentinel events are investigated. Management would do their RCA and I'm sure the issue with alarm fatigue would be ignored or underplayed (Something bad happen? make sure an alarm sounded. If staff ignored it, it must be the fault of the staff). I doubt any one person would be in trouble as it was a collective/systemic failure, but I don't know exactly what would have come of it. Likely a policy change or daily reminders for the next few weeks about not ignoring the monitors even if it has been going off nonstop for hours. Maybe extra charting or peer audits. It's a lot less expensive and effort to put pressure on staff than it is to change technology (even if it is as little as setting different, more sane, defaults). Depending on what was recorded from the monitor to the chart, if it looked like there wasn't a delay in resuscitation/cardioversion (like if the lethal rhythm wasn't recorded initially), it may have been just put down as clinical course for the patient, like you suggested. My perspective of that place is a bit jaded (and therefore biased), that place was a toxic burn-out factory. BTW, "post mortem"? Thanks, the morbid humor made me laugh!
_yb2s 2y ago
Hospitals have a sort of manic "New York Stock Exchange" energy and environment to them... The entire environment of a modern hospital seems brutally incompatible with the type of peaceful relaxing environment you'd want to reduce stress and improve patient outcomes. Bright lights, constant noise, loud electronics, preventing patients from sleeping based on whatever schedule is convenient to medical staff, etc. I think they could substantially improve patient outcomes by taking some tips from the best modern birthing centers, and make a quiet, relaxing, dimly lit, and peaceful environment at hospitals. I'd also say add some plants, natural (wood) surfaces and natural light, but realize that might make it hard to keep things sterile and private. It would make sense to create a rough schedule for each patient also with a consistent "left alone unless there is an emergency" time for sleep, etc. I would imagine a calm and quiet physical environment would also reduce stress, fatigue, and improve performance of the medical staff themselves.
- Aeolun 2y ago
  Don’t think it’s so unrealistic to make a sterile green environment with fake plants. Fairly certain it doesn’t matter too much.
- nradov 2y ago
  You're not wrong. ICU delirium is a serious problem. https://www.statnews.com/2016/10/14/icu-delirium-hospitals/ https://www.statnews.com/2016/10/14/icu-delirium-hospitals/ But it's tough to make improvements. Regular hospital design is (roughly) optimized for staff productivity. They need to be able to treat and monitor many patients simultaneously which requires clear sight lines, good lighting, and a high level of automation. A more humane hospital design would also require more staff at a time when we already have a severe shortage. Where would the funding come from?
- matheusmoreira 2y ago
  Hospitals are not "peaceful relaxing environments". They are large scale industrial operations designed to process as many people as possible. There simply aren't enough resources to afford every single person a "relaxing environment". You do the best you can for as many as you can. All this "relaxation" stuff will quickly be converted into spare capacity the second large numbers of severely wounded people start showing up at the emergency room. If you're a multibillionaire then obviously you can just hire and equip your own private medical team that will focus 100% of their attention and care exclusively on you and your needs. The vast majority of the humans will never have that luxury. Normal people enter the system and are processed like everyone else.
Buttons840 2y ago
There will always be false positives and false negatives, they have to be balanced. If the cost of a actual negative is 100 and the cost of an actual positive is 1. You'd expect there to be approximately 100 times more false negatives, because we want to be 100 times more sensitive to the costly negative condition. I'm this sense, the alarms in hospitals make sense. Actual negative are very costly. But this is a cold mathematical analysis that doesn't consider alarm fatigue and the cost of people learning to ignore the alarm. I wonder how to best model human nature in this calculation? An optimal solution would require considering all alarms, and modeling the fact that every alarm given is another alarm ignored (assuming the hospital is operating at capacity, if it's below capacity the solution is easy, just manually check all alarms). This system might realize that the 4th "no pulse" alarm of the night for Alice would detract from the 1st "no pulse" alarm for Bob, and that Bob's is more likely to need attention. I'd be terrified to program such a system though, and from what I've seen in corporate programming environments, I'm not confident any company could get this right.
- LorenPechtel 2y ago
  You have it backwards. They really do not want false negatives because that gets them sued. Thus the system will be set up to err on the side of false positives--the current liability climate does not blame them for alarm fatigue. Consider a local case (although it's possible it was overturned on appeal): Yes, the doctor was unquestionably playing loose with standard safety precautions. His behavior transmitted blood-borne infections. He died in prison which was well deserved. However, the lawyers went hunting for some deep pockets. The manufacturer of the drug involved in the cross contamination. They made various size vials, including some that were bigger than would be used on one patient. This permitted the doctor to contaminate between patients and got them hit with a $250M verdict. (Never mind that had they truly only used clean needles with them like they should have there never would have been an issue. They used a new needle but the old syringe.) That's the sort of insane legal pressure driving the garbage.
takinola 2y ago
I used to work as a field engineer on oilfields and rigs. We had panels of equipment, each with their own alarms and beeps. Once the rig manager (the client) remarked that we were ignoring the alarms, snidely insinuating that we should pay more attention given the possibility of things going wrong. The reality was we knew what was going on just by listening to the alarms. I could predict which alarm was going to go off before it did and so I could safely (appear to) ignore them. I would only panic if an unexpected alarm went off (or happened in an unexpected sequence). It is possible the same situation was going on in the hospital.
- KennyBlanken 2y ago
  Nope. Alarm fatigue is a well documented problem in the medical field. Like residents who are getting a few hours of sleep over days worth of high-stress / high-stakes work, poor hand-washing between patients, and not clearly printing one's handwriting on prescription forms - all things that kill patients - doctors and hospital administrators just don't care enough. For a profession that is supposedly so pure morality-wise - do no harm, patient privacy, etc - doctors are remarkably careless.
  - hiAndrewQuinn 2y ago
    "They just didn't care enough" is an argument which can explain everything about how 1 person operates, half of a 10 person group, and roughly 0% of an entire profession. It's a question of the economic incentives at play far more than doctors universally deciding not to give a shit. The economic recommendation is to deregulate the medical personnel industry and allow supply to increase. A great many smart and good people would love to become doctors but aren't in love with 5 years of residency and taking a quarter million dollars in debt to make less than their dropout cousin does at Netflix.
    - nabusman 2y ago
      Pure deregulation can lead to a bit of anarchy, but a more measured approach that ensures that the regulation doesn't act as a way to decrease supply and increase profits for the industry would make sense. Probably something for Lina Khan to look into.
deanresin 2y ago
My Mom recently had brain surgery and was recovering. Her machine would go off all the time and it took forever for a nurse to come buy and fiddle with it. I would joke to my Mom that it probably meant she was dying. Those beeps were so annoying. If anything, they should be beeping in the nurse's control area. It seems ridiculous it has to beep loud enough for a nurse down the hallway to hear it when it never seemed to be anything urgent or dangerous. Certainly, no one came running.

tux3 2y ago

Trying to figure out which melody was which in an emergency doesn't seem like the most human-friendly. Contrast with the GPWS warnings in aviation, which tells you what the problem is (TERRAIN TERRAIN) and what to do (PULL UP) in a progressively more alarmed voice as things get worse. (Well.. Sometimes you hear of some particularly bright individuals who think the bank angle warning is a checklist item, but it's generally hard to get these wrong, compared to many other beeping warnings)

sebmellen 2y ago
GPWS warnings should be the gold standard for any sort of urgent audio alarm. Examples: https://www.youtube.com/watch?v=W5Z-d1Zx02o https://www.youtube.com/watch?v=W5Z-d1Zx02o
- imglorp 2y ago
  At :42 I think the buzzing sound is the "stick shaker" stall warning. It literally shakes the pilot's control yoke. So not only is it an alarm, it's also reminding the pilot of the correction needed: to push the control forward.
  - varjag 2y ago
    Wouldn't that be pull backward?
    - seabass-labrax 2y ago
      Not in this case, because the 'stick shaker' activates when the aircraft is stalling or close to stalling. The only sensible option in this scenario is to lower the angle of attack, that is, pitch forward. If you have both the GPWS 'terrain, pull up' warning and the stick shaker warning simultaneously then you are in a sticky situation indeed.
      - krisoft 2y ago
        > If you have both the GPWS 'terrain, pull up' warning and the stick shaker warning simultaneously then you are in a sticky situation indeed. Yeah. To quote the movie Wargames: “The only winning move is not to play.” That is a pilot should do their best to avoid getting into anywhere near that situation.

g15jv2dp 2y ago

What's not clear from this webpage is whether these are actually used anywhere. Are they? I couldn't tell.

thomasthorpe 2y ago
Yes, well, some. To gain certification, often something customers require, medical devices must comply with standards such as ISO60601 (hardware) ISO62304 (software) and ISO13485 (process, quality management). The alarm waveforms described are within the scope of the hardware standard guidelines, sufficiently common that application notes such as this exist. https://www.ti.com/lit/pdf/slaaec3 https://www.ti.com/lit/pdf/slaaec3 [ti.com]
- HeyLaughingBoy 2y ago
  > often something customers require A bit more than that. Certification is required in order to put your product on the market. Whether or not customers require it is irrelevant.

davidw 2y ago

It gives me anxiety just looking at this. Add this to the list of things I don't want to work on.

HeyLaughingBoy 2y ago
On the producing or consuming side? FWIW, I found the article interesting as I'm starting a new Oxygenator project so I'm probably about to become even more familiar with IEC60601 :-(
- davidw 2y ago
  I don't want to work on software where bugs might cost someone their life.
  - HeyLaughingBoy 2y ago
    I get that, but it's very unlikely to happen. The benefit of your code vastly outweighs the potential downside. As engineers, we're used to only hearing about the problems. It's really gratifying when you hear from someone who says, "tell your engineers that they saved my life."

blackeyeblitzar 2y ago

I absolutely hate the poor design of medical equipment found in hospitals. The worst thing by far is the constant beeping and noises in the room, which totally disrupts rest and hurts recovery. It is SO obvious that this hurts patients (and visitors), that I cannot believe the entire medical industry (nurses, doctors, hospital administrators, equipment makers, insurance companies) have failed to do anything about it. It also makes it hard to know if some sound is expected or if it is a signal that something is wrong. In addition to this, I’ve seen nurses make mistakes several times because the equipment is too confusing. Once, I had to page the nurse myself because the IV they thought they set up was not functioning and I was able to discern that from the screen on the IV machine (which said one particular drug was not active) but they had not noticed, essentially administering an imbalanced cocktail of drugs for a period of time. My take - the medical industry has too many barriers to competition, and it is too difficult for people who work with these things to do anything about it as well. It’s unclear who the buyers are at a hospital or how a startup could reach them. It’s also unclear what sort of interoperability (for example with Epic for charting) is needed. Regulations also make it difficult to get devices approved and investors are less likely to support a startup in this space.

atahanacar 2y ago
>I’ve seen nurses make mistakes several times because the equipment is too confusing. Once, I had to page the nurse myself because the IV they thought they set up was not functioning and I was able to discern that from the screen on the IV machine (which said one particular drug was not active) but they had not noticed This doesn't sound like the equipment's fault.
- blackeyeblitzar 2y ago
  Technically no, but watching them debug it and configure it made me think it’s too complicated. They basically had to figure out the right sequence of buttons to hit.
mschuster91 2y ago
It's a necessity, a side-product of not having anywhere near enough nurses, assistant staff and doctors in hospitals. They're juggling alarms constantly (which have to blare in a cacophony) and speed from one patient to the next. Ideally you'd have a 1:1 (or better!) assignment between a single patient to a single nurse in critical care, 1:3 for patients that can't move around on their own (and thus need more assistance, even if it's just helping them to eat or go to the loo), and 1:5 to 1:10 for everyone else. The sad reality is that even in Germany, you have care home staff calling in the fire department to assist because there were just three staff in a night shift, having to deal with 170 patients. [1] https://www.morgenpost.de/berlin/article242110812/Kurioser-Grund-Feuerwehr-Polizei-ruecken-in-Seniorenheim-an.html https://www.morgenpost.de/berlin/article242110812/Kurioser-G...

ano-ther 2y ago

I seem to remember that some of these sounds (perhaps the one with syllables) were originally part of a joke paper and that the author was quite astonished how they became part of a standard. Unfortunately, I cannot find the article anymore.

tverbeure 2y ago

A friend of mine used to have a small side business selling loudspeakers for medical equipment. She order them in Asia and had her own little certification lab at home: heat chamber, impedance testing, that kind of stuff. Every so often, she’d receive an order of a few hundred speaker, and test them one by one. It’s a low volume but high margin business. Some of the issues were the constant fight against the factory not following design requirements to cut costs, knockoffs etc.

roughly 2y ago

The cardiac alarm tone is unexpectedly jaunty.

graypegg 2y ago
Out of all of them, it’s definitely the most “washing machine is done”

strnisa 2y ago

The standardization of medical alarms was important when introduced, providing consistent and clear communication across devices and countries. However, with modern technology, these standards may now limit innovation. It seems to me that clear verbal alerts like "BLOOD PRESSURE VERY HIGH" could be more immediately understandable than tones. A hybrid system combining verbal alerts with alarm tones might be a good compromise for clarity and international usability.

ncallaway 2y ago
I don’t know, I kinda think if you’re going to have verbal warnings you kinda need a centralized system that processes all alarms to triage them like in an airplane. If even 2 verbal alarms are going at the same time, it’s going to create a chaotic environment. In a decentralized system, I think tones have less of an overlapping problem.
- Aeolun 2y ago
  If two of these tones sound at the same time, I’m fairly certain I couldn’t distinguish them.

throw46365 2y ago

I remember my Dad, in his last day conscious, with a fluid line in that kicked off some sort of pressure alert every time he raised his hand to his face… which he did compulsively because of his confusion on top of his dementia. The nurses obviously couldn’t respond to it each time, but nor could they switch it off altogether, and it didn’t reset after any period of time. My siblings and I took turns to gently hold his arm down on the side of the bed… which became just holding his hand, which I still miss.

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ijustlovemath 2y ago

We're building a life critical medical device, and I haven't seen this mentioned, so I thought it was worth contributing: The use of these alarms is not something imposed by the manufacturers, but by the standards, eg 60601, 62304 etc. For devices involved in diagnostic, or more importantly interventional care, you are required to have alarms within certain auditory and visual thresholds, and a lot of them have mandated silence times (in a life critical system, you can only silence a true alarm for 120 seconds at a time). Then again, "ALARM" as dictated by the standards means something truly emergent, though the wording can feel a bit fuzzy at times. Trust me, alarm fatigue is a known phenomenon to these manufacturers, and theres been a recent trend (with, eg, the Dexcom G7) of giving users more control over delaying alarms, silencing them until you can respond etc etc, which has its benefits, especially as quality of life is concerned. You'll have a hard time convincing the FDA of this for critical devices like those found in hospitals though.

jimmySixDOF 2y ago
The airline industry went through this too and have moderated requirements to be more understanding of who it's consumers are and when. One of the big near miss cases was QF32 out of Singapore where they had over 50 alarms to deal with in addition the the emergency at hand. Alarm pollution is a real UI/UX dilemma.
- hejdufufjrj 2y ago
  In an airplane at least all the alarms are integrated, but in a hospital room you'll have 15 devices from 7 manufacturers spanning 5 generations.
- amelius 2y ago
  Maybe someone can train an AI to decide which alarms need immediate attention, given N staff members available.
  - throwaway765123 2y ago
    Yikes I hope this is tongue-in-cheek, I definitely don't want a statistical process deciding whether to surface a life-critical alarm to healthcare staff

userbinator 2y ago

Some of them remind me of YouTuber Ashens' intro sound.

jill4545 2y ago

An amendment to IEC 60601-1-8 introduces the concept of acoustic icons. These are the alarms that mimic the sound of what the device does e.g. a ventilator would be a sighing/breathing sound as well as a pulse to indicate if its alarm with a priority. This directs the clinician to know immediately which device is alarming and how high the priority is as opposed to a plethora of beeps and pings all merging together. Could be a game changer.

kioleanu 2y ago

Only very slightly tangential, I remember when my son had his surgery and had to be in the hospital, they would have these dosing machines for the medicine and they would start throwing a warning sign 3 minutes before the syringe was empty, every 30 seconds and then a proper alarm when it was empty. Now, we were supposed to call a nurse to remove the syringe, and each nurse had their own preference on when to be called. Some said call us when the warning starts, some said call us a minute before and some said call us when the red alarm goes off. We found this strange until one of them explained it is simply related to the amount of chit chat they wanted to do with us, as the syringe always had to go out at the red alarm

Shawkam1234 2y ago

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chess_buster 2y ago

There's a dissertation from a Professor of Health Care about Alarms in ICUs: https://uol.de/f/2/dept/informatik/download/Promotionen/Cobus_Diss.pdf https://uol.de/f/2/dept/informatik/download/Promotionen/Cobu...

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imadoctor 2y ago

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