Alarms in medical equipment | Hacker News Reader

Alarms in medical equipment

th.id.au

185 pointsgaudat112 comments

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.

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.

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.

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.

Maybe someone can train an AI to decide which alarms need immediate attention, given N staff members available.

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

If it statistically saves lives?

It's the same as allowing full self driving cars which on average are safer than human drivers but sometimes accidentally drive into a fire truck because they couldn't train an image classifier to more accuracy than 99%.

> Maybe someone can train an AI to decide which alarms need immediate attention, given N staff members available.

The words you've used could hypothetically mean some future artificial general intelligence that does not currently exist and there is no guarantee will ever exist, especially within the lifetimes of those participating in this thread. That could obviously be quite good.

"AI" as currently defined by marketing and pop culture to mean machine learning, large language models, etc. should never be allowed to make a medically important decision. We've already seen beyond any reasonable doubt how risky it is to even treat them as a natural language search engine, the idea of handing over life-or-death decisions to them is literally insane.

The FDA would not let this fly. To get a device in the hospital, you have to enumerate EVERY failure mode that you can reasonably protect against, as well as the ones you can't. Some of these failures are crucial enough that they qualify to be required to implement an alarm for.

There's a reason everyone is so loud in the hospital, it's because we have to be to be there in the first place.

58 faults on the ECAM. Source: https://youtu.be/a-4FBN8OTkk

Props to Airbus for proper UX and information prioritization.

Huh, that title smells of tabloidization. I know about this incident, the "mid-air explosion" have to do with an uncontained disintegration of 1 turbine (with shrapnel flying that breached the wing, luckily not the fuselage), but the title makes it sound the whole plane exploded...

this is very true with diabetes equipment since there is constant alerts (for example from insulin pumps) of low battery, undelivered insulin, etc. I think it definitely helps to give users the right amount of control if it's non life critical like a CGM or for insulin delivery.

Insulin delivery is considered life critical by the FDA, because the failure modes of those devices can involve coma, brain damage, and even death. Some of those alarms will still be hardcoded, and for good reason!

I agree, but something like "incomplete bolus" doesn't really make sense to me and I think those types contribute to alarm fatigue. The key issue with T1 diabetes is hypoglycemia, which can cause acute damage and death, so in theory not having insulin on isn't as big of an issue (assuming the patient is actually trying to control their disease and checks blood sugar etc, in the alternate case the alarms probably don't help much). Of course, I agree something like a hypoglycemia alarm is important

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??

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.

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.

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.

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.

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.

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.

> 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.

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.

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.

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.

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.

You’ve hit the nail on the head. It’s often tedious getting one to work.

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.

> 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.)

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.

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.

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).

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?

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!

They will try as hard as they can to pin system failures on the unfortunate person who was in charge of the system.

Or, a local case, the nurses were complaining about shoddy supplies. Eventually the holes in the swiss cheese lined up and a baby died. The hospital tried to treat it as a murder by the nurse. (Claiming the line was cut, rather than it broke.)

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.

Don’t think it’s so unrealistic to make a sterile green environment with fake plants. Fairly certain it doesn’t matter too much.

You're not wrong. ICU delirium is a serious problem.

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?

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.

I suspect the patients would fare better if active noise cancelling headphones were issued to every patient.

I've yet to see a study that shows noise cancelling headphones reduce patient mortality in any way whatsoever. Until there is such a study, money is better spent on things that are actually known to reduce mortality. Such as drugs.

I honestly believe that a pair or noise cancelling headphones and an eye mask would have statistically noticable effects on outcomes. The bright, noisy environment of a hospital makes good, natural sleep basically impossible and that is brutal on even healthy people.

My ward even managed to have the (networked digitally controlled, and do presumably very expensive) lighting set up so the night lighting was inside the curtains and shining directly into the bed spaces, and the main ward lights would come up if you touched the wrong thing (even the nurses weren't quite sure exactly what the proximal causes of lighting changes was). With the pumps alarming the whole time (about once per night, per patient, up to 20 minutes until resolution each time) plus all the other regular medical checks preventing any extended quiet time, it was absolutely exhausting at a very deep level.

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.

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.

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.

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.

"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.

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.

> deregulate the medical personnel industry and allow supply to increase

And salaries to plummet.

Who's gonna be the first to volunteer to spend about 14 hours of their day in some shithole hospital nearly every day sacrificing their own health and sanity for the sake of others, all while making a fraction of what people here make? Deny people their prosperity and suddenly going to medical school turns into a stupid and irrational decision and something only rich people will put up with for the status.

Plummeting salaries for doctors means better average healthcare at all price points for the rest of us.

Plus, play the tape forward. You're working 14 hour days and your pay has been halved in the last 5 years. What can you negotiate on? More pay probably isn't an option. How about working only 12 hour days for 6/7s the (already reduced) pay? That might be doable. In a decade, you might even be working a normal 9 to 5 again. The horror!

Negotiate? Just quit. At some point you're better off doing literally anything else with your limited time on this earth. Way too much time and effort for too little reward. Who's looking forward to doing a decade of hard training only to end up with some 9-5 job and salary? That's just absolute nonsense.

Becoming a doctor is quite simply a stupid decision if you're not gonna get rich off it. You're replying to a citizen of a country which implemented your idea and then some. Believe it when I say the "get into medical school and you're set for life" meme has worn off.

You haven't seen the damage that stupid indebted underpaid doctors are capable of causing. I'm actually afraid of getting sick. Killing patients? I've seen worse.

Your profile indicates this is Brasil... Let me do a quick Google search.

"[T]he Brazilian healthcare system has achieved significant success in improving population coverage, reducing infant mortality rates [a 4-fold drop!], and controlling infectious diseases." https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10231901/

It sounds like doctors are actually doing a much better job there nowadays than they were 35 years ago. The facts I see simply don't match your outrage.

Even the article you cited contains allusions to the truths I will write about in this comment. "Unequal access to healthcare services and resources", "significant disparities in healthcare outcomes between different regions" and the most hilarious point of all... "Low quality of care". Just lovely.

Let's rid ourselves of all these polite euphemisms though. Here's a likely incomplete list of all the things that you don't see.

What you don't see is the communist president of the worker's party who is literally quoted saying "we need to create a new generation of leftist doctors who accept working for less". Population needs doctors, and they vote, so give them what they want: more doctors. And when you want quantity, then obviously you also want cheap. Flood the market with doctors, open hundreds of new schools with ever more lax filters and bring in doctors from neighboring countries too even though they seem to be in even worse shape than us. Problem solved, look at all those happy voters.

The government's latest move was to remove doctors from the decision making positions that control residencies in an obvious preparation to flood the market with "specialists" by dumbing down the requirements and opening new residency programs, no doubt without any concern for quality. You might be skeptical about this claim but these are people who are stupid enough to believe a nurse with 10 years of job experience is equivalent in knowledge and skill to a doctor. At least one such "illustrious" politician can be directly quoted on that.

There's already a huge number of medics, they just happen to be concentrated in the major cities and capitals. The simple fact is nobody wants to live in some undeveloped shithole. Living in Brazil to begin with is punishment enough, there just aren't many maniacs around here who are willing to work and live in the literal amazon jungle. Even comically high salaries fail to attract doctors to areas like that. Partly because quality of life is abysmal and partly because those little villages are so poor they're actually likely to default on those payments anyway so there's no point. Those are the places where the government wants to ship doctors off to though. You'd think they'd develop the country instead so that people in general would want to move there but that's too difficult. Better to just destroy the profession of the "mercenary" doctors instead until they're so squeezed they have little choice.

You don't see the hundreds of brazilian medical schools soaking up billions in government student loans while providing mediocre education. Student loans are very efficient at making school administrators very wealthy. They were devastating for academic integrity everywhere in the world including the US but this country always manages to make it worse by not even pretending to give a shit about quality. In the US medicine apparently escaped that fate due to stronger regulation. In Brazil? So many of these medical schools do not even have an actual hospital for medical students to practice on. How do you become a doctor without seeing patients? You don't.

You don't see the palpable pessimism in health care workers, as a class. What was once a profession that guaranteed prosperity turned into essentially a joke. Doctors generally do not recommend that their children follow in their footsteps. Why would they want their children to bust ass in medical school just to make six dollars a patient? That's just stupid. And those are the lucky ones. The family medicine workers of the study you cited usually make even less than that. This new generation of doctors is feeling the pressure, meanwhile older generations of doctors are taking the wealth they built up and bootstrapping actual businesses instead.

You don't see the 40 thousand newly minted doctors of dubious quality entering the job market every single year. That obviously brings about difficulties with job and residency availability, not to mention the massive and constant downward pressure on salaries. So how does the typical newly minted doctor react to this adversity? Charlatanism.

You don't see the rampant charlatanism on social media. Social media platforms are absolutely filled with them. "Professionals" promising miracle cures, promising results, just basically doing everything that medical ethics says they can't do. That includes passing themselves off as specialists while having a fraction of the education, or just straight up advertising "specialties" they just made up on the spot.

Hilariously, these charlatans are actually the ones who are making it in this distorted reality. They do things like charge people thousands for aminoacid injections that literally do nothing. Brazilian medicine regressed to literal "blow smoke up people's ass" charlatanism and these people are getting rich off it. Do you know what coffee enemas are good for? I haven't the slightest clue but you bet there are doctors doing that to patients literally right now. Things are so screwed up even non-doctors, people who have never stepped foot in a medical school let alone an operating room, have grown bold enough to do "simple procedures" on their customers.

Ever seen an unemployed doctor? Ever seen doctors become Uber drivers? Cashiers? I have. It used to be a meme. Then it actually started happening. Salary only ever decreases. We have emergency services paying the lowest and ever decreasing salaries. What kind of doctor do you think that's going to attract? The simple fact is there aren't enough hospitals in this country for all of them. Most of the ones we do have are in such disrepair that nobody sane would actually want to work there.

The decentralized public health care system familiy medicine situation is even more precarious. There are workplaces in this country that do not have a working sink for doctors to wash their hands with. You simply cannot exercise your profession with dignity under such conditions. The smarter, better doctors have better options and don't subject themselves to that. The ones manning the public health system are generally the desperate and indebted ones. The ones who weren't good enough to match into a good residency.

You don't see the criminally stupid doctors who fuck up so bad they end up on national television. Doctors working an ER who are so stupid they don't run a simple EKG on a patient with textbook myocardial infarction symptoms. Imagine being this fuckup's lawyer. And it's not an isolated case either, their numbers are increasing. The fact is in Brazil any moron can become a doctor these days and you better believe it shows. The problem with that is people's loved ones die in the process and there's no amount of damages that will bring them back. A few years ago I nearly died of appendicitis myself because they initially blamed my symptoms on COVID19. The doctors who saved my life were all older than the public health system the paper you googled talks about. They're becoming rare now, and knowing that makes me afraid of getting sick again.

I seriously hope you reconsider this "just increase supply" nonsense. I know HN hates doctors and it's kind of a tall order but I sincerely hope what I wrote here makes some impact. Simple solutions like that will not accomplish what you want. To put it mildly.

The easiest way to increase the supply of physicians would be to increase Medicare funding for residency programs. We already have a surplus of smart and good people who would love to become doctors. Every year some of them graduate from medical school with an MD/DO degree but are unable to practice medicine because they don't get matched to a residency slot (some of them do get matched the following year).

https://savegme.org/

There has already been deregulation to an extent. The scope of practice for lower licenses such as Nurse Practitioners and Physician Assistants has been increased in many states such that they are now allowed to perform most primary care services. This is a great option for other smart and good people who don't want to spend 3 - 7+ years in residency and take on enormous student loans.

Alarm fatigue is very real. And the lack of sleep is very real.

Where you go off the rails is with saying "don't care enough". This is a market problem, not a problem with individuals. "We don't overwork our people" isn't a selling point with insurance. The budget is pretty much fixed, a company that doesn't overwork their people ends up in the red.

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.

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)

GPWS warnings should be the gold standard for any sort of urgent audio alarm.

Examples: https://www.youtube.com/watch?v=W5Z-d1Zx02o

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.

Wouldn't that be pull backward?

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.

> 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.

What i heard is that it is designed to imitate the stick sensation smaller airplanes have as the wind buffets the controll surfaces when a stall develops.

And pilots from an early stage in their flying training conditioned to push the stick forward when that happens.

Making this my PagerDuty alert sound https://youtu.be/fbfVGIBcD8c?t=77

I used to have pull up as my ringtone, freaked my uncle out (who's a commercial pilot) when he was over for dinners. Or at least he pretended to be :P

I was half-asleep travelling on a train when a kid blew a wistle near me which sounded exactly like the stall warning horn of the Cessna-150 i was learning to fly around that time. It jolted me awake right away. I had this clear clarity in my mind that i have to push the controls forward until i realised that I am nowhere near an airplane.

Now I have this.

https://looptube.io/?videoId=W5Z-d1Zx02o&start=77.1286764705...

They also have their share of cavalry charges and buzzers. Plus the plane sometimes calls you a retard

At least chimes are language-agnostic. Verbal warnings like "pull up" are only good if you have a reasonable grasp of English.

At the very end, there's some examples of more literal sounds. It says there hasn't been a study, but I would bet they're a lot more clear with out having to resort of the aviation standard of "just learn basic english".

buh-bump is cardiac stuff. wiSShhh... wooosSH is respiratory stuff.

Only thing is, I bet you can hear sounds similar to those in a hospital. The "beep beep" they put over it might not be enough. Still a really interesting research topic!

True, but professional pilots from all countries are expected to be fluent in Aviation English. https://en.wikipedia.org/wiki/Aviation_English

Yes, but in a high-stress environment, your ability to process words--especially those not in your native language--goes down the tubes quickly. Even if you were to tune out sounds to the same degree that you tune out words, at least the sounds would still have a relatively universal meaning, e.g. loud klaxon for big problem, soft chime for minor notification.

Another good thing is that they allow for talking over them better. The same way you may sing along to an instrumental-only music track using whichever lyrics you prefer.

I wonder how much information any 1 medical device with an alert knows though. GPWS has the benefit of being part of 1 system, where (I think, no experience here) hospitals seem to treat equipment as singular items that do 1 thing or are meant for a specific area of responsibility in an operation. Like a vitals monitor might not know what the drug pump is doing.

I could imagine

    ventilation? arrhyth-*C-chord*-ARRHYTHMIA! CHECK PUMP! HEART RATE!

coming from different devices to be pretty distracting.

I think GPWS can set windows of cases where an alert is given. Like, a terrain warning isn't much help when landing. Maybe there's something like that already for medicine, but a device who's job is to consume information from other devices, and only provide alerts based on rules the staff can configure before an operation, could be a thing that's useful.

That's really the problem many here are describing. 60601 mandates what alarms shall be active, but it spans a single device. If you have, e.g., 10 ventilators in a room that are alarming, you can't silence them all with a single button press.

I can kind of understand why it ended up that way. There's some benefit to just assuming, nothing works together. It's at least a consistent state of affairs. You can just wheel in any heart rate monitor, and you only need to understand that heart rate monitor.

But it seems like a space that's really ripe for improving. We have very reliable simple protocols you could hook these all into. Imagine it was law that every medical device had to emit the numbers it displays on something like an ODB2 port. Something that can be visually checked to be plugged in, be unplugged and replugged with no handshake, and handle daisy chaining so in the event the "network" breaks in two, or a device goes down, you still get information from the remaining network/it can reroute.

For such a highly regulated industry... you kind of wish they would regulate. I guess status quo is also a regulation.

Interoperability is definitely a problem. I've been in the industry for quite some time, and at one job we got to shadow med lab techs, since they were the operators of the machines that we built. Their workload is insane and after an hour watching them work, I could identify a number of new products that would help them. I brought it up to my management and learned that "marketing is aware of those problems and we're devising solutions." No idea if those solutions ever hit the market -- this was over 10 years ago.

At the time, the solution to interoperability was to buy all your lab equipment from one manufacturer, who would use their own (usually proprietary) protocols to tie things together. That way, at least even if they weren't actually interoperable, the UI's and workflows were mostly consistent.

A large part of the problem is that hospital IT is understandably hostile to anything connecting to their network, so all the stuff we were building at the time that talked to each other, had to use its own standalone network, or serial ports (ugh!).

Standards like IEC-60601 or 62304 (my daily bread) are easier to adopt because they address patient safety. I suspect it would be much harder to mandate an interoperability standard unless you could show that it improved safety instead of "just" making the healthcare provider's job easier. Or maybe it exists, but just never came up on my radar.

Inter op has a lot of different standards but support for all those standards is limited. Here’s an example:

https://www.astm.org/f2761-09r13.html

As you point out the corporate network operators tend to have a different set of priorities but even there too standards exist. Here’s an example:

https://www.iso.org/standard/72026.html

One significant difference between verbal warning systems in airplanes and those in medical environments, such as hospitals, is the level of environmental control. In an airplane, the environment is highly controlled, with a single set of systems specific to that aircraft. In contrast, hospitals often have multiple systems operating simultaneously in the same room or nearby. This can lead to cognitive overload when multiple systems issue verbal warnings simultaneously. In such scenarios, tone alarms might be easier to manage and differentiate than multiple overlapping verbal warnings.

> In an airplane, the environment is highly controlled

Aircraft systems are developed independently and added as options to planes. Which means they get swapped out, there are variants in capabilities, and multiple manufacturers involved.

> This can lead to cognitive overload when multiple systems issue verbal warnings simultaneously.

This is a known phenomenon on flights as well. There is some speculation it played a part in Air France 447. The plane technically _was_ telling the pilots the _precise_ problem they faced, but in the sea of other warnings they were entirely lost.

> tone alarms might be easier to manage and differentiate than multiple overlapping verbal warnings.

If you're a nurse, is the fact you have a ventilation alarm in one room and a temperature alarm in a different room that can be discerned without visual confirmation a useful feature in a health care setting?

I think the big difference is your flight has 2 people responsible for hundreds of lives. In the hospital you would hope the ratio would be more favorable.

>Aircraft systems are developed independently and added as options to planes. Which means they get swapped out, there are variants in capabilities, and multiple manufacturers involved.

He means there is only ever one aircraft (the one you're flying) and hundreds of patients in a hospital.

Imagine if you will, hundreds of GPWS alarms are blaring off all screaming TERRAIN PULL UP TERRAIN PULL UP PULL TERRAIN UP UPTERRAIN PULL TERRPULLAINUP UPULLPTERRAIN TERRPULLAINUP PULLRAIN TEUPR...

That's both alarm fatigue[1] and the alarms being wholly impractical to begin with. For starters, which GPWS wants to be pulled up again? You can't know, there's hundreds! And that's even assuming you can make out TERRAIN PULL UP in the maelstrom of noise.

[1]: https://en.wikipedia.org/wiki/Alarm_fatigue

Yea, I kinda got myself there in a roundabout way in the end.

In any case, if that's the environment, then it reminds me of our solutions for broadcast studio alarms. There was a combined master tone alarm in the engineering control room, and a set of annunciators for each station, with three levels of severity for each. You'd hear the tone, snap your head around to look at the board, and quickly be able to tell what you were dealing with and where the priority problems were.

Likewise, in the hallway leading up to the studios, there were colored flashing lights above each studio door that also displayed the alarm level for that studio. Those were completely silent, for obvious reasons, but their flashing pattern got your attention anyways. They were arranged vertically according to severity so even if you were color blind you could understand them at a distance.

Then inside the studios there were more detailed annunciators that would actually display which part of the air chain monitoring was causing the global alarm signal. These were also silent, but did not flash, and had a clock that would pause when the first error became displayed.

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.

>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.

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.

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-G...

Thank you for bringing that up, understaffing affects everything and harms patients. No set of alarms will ever replace the benefit of having enough people working.

I don’t disagree but I’m not sure how to make the costs of healthcare work with those ratios

Get rid of bureaucratic bullshit and you'd get > 250 billion $ a year [1]. Get rid of insurances and other middlemen and you'd get another 450 billion $ a year by going for single-payer [2]. Then, get the homeless enrolled in insurance as well - even if the government pays the premium, every single homeless person costs > 18k a year in ER visits [3], a lot of which could be prevented if these people could go to a doctor before they'd be sick enough to incur serious ER costs. And finally, get as many homeless drug addicts back into some sort of stable housing. A lot of drug usage "on the streets" is self-medication to cope with the immense stress that comes from being homeless. Yes, there will always be a certain percentage of hardcore voluntary homeless people, but that's way better manageable than the status quo.

That should be way more than enough to hire enough nurses.

[1] https://www.americanprogress.org/article/excess-administrati...

[2] https://ysph.yale.edu/news-article/yale-study-more-than-3350...

[3] https://www.newsweek.com/homeless-americans-are-costing-us-m...

About 15 years ago I worked for a medical usability firm. We did a review of the Baxter Large Volume Infusion Pump. Among dozens of other issues[1] we found, the absolute mother of them all was the stop button, which had been overloaded to have multiple functionalities:

If you push the button once, it would stop infusing drug into the patient.

If you push the button twice, it would EMPTY THE SYSTEM - as in, run the pump continuously, infusing all remaining drug into the system, at high speed.

We ran usability tests where we'd say to the nurse "wrong drug! stop! you're giving the patient the wrong drug!"

90+ percent of them did what any human would do - jab STOP over and over. Whoops, patient's dead.

In part because of our report Baxter was forced to recall[0] hundreds of thousands of the pumps and pay for their replacements with competitors' products. The stock dropped by 30% in a day. Sadly I didn't short it, or I'd be [checks notes] in jail.

[0] https://archive.is/s1wEU

[1] like drug libraries where sometimes the units were displayed, sometimes they weren't, and sometimes they were displayed in your "preferred" units even though the number being shown was in a DIFFERENT unit and the system didn't translate it, just showed the wrong value.

> If you push the button twice, it would EMPTY THE SYSTEM - as in, run the pump continuously, infusing all remaining drug into the system, at high speed.

Wow this sounds so dangerous and so easy to predict.

If you want to feed observation data into Epic for charting that is quite easy. It supports inbound interfaces using HL7 V2 Messaging and FHIR standards for things like medical device waveforms, aggregated device data, vital signs, etc. Other major inpatient EHRs have similar functionality.

https://open.epic.com/Interface/

The FDA has a whole program office to assist startups with medical device innovation. They can help you a lot if you engage with them early in the development process and explain what you're trying to accomplish. Think of them as partners, not obstacles.

https://www.fda.gov/about-fda/cdrh-innovation/activities-sup...

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.

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.

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.

If two of these tones sound at the same time, I’m fairly certain I couldn’t distinguish them.

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

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

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

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 :-(

I don't want to work on software where bugs might cost someone their life.

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."

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.

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.

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

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

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

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 [ti.com]

> 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.

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

The cardiac alarm tone is unexpectedly jaunty.

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

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