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Alarms in medical equipment

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Re: Alarms in medical equipment

#61

Post by Aeolun »

ncallaway wrote: post #45
strnisa wrote: post #42

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 com…

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.

Re: Alarms in medical equipment

#62

Post by krisoft »

varjag wrote: post #54
imglorp wrote: post #10

Earlier quoted context omitted.

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?

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.

Re: Alarms in medical equipment

#63

Post by krisoft »

seabass-labrax wrote: post #56
varjag wrote: post #54

Earlier quoted context omitted.

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.

Re: Alarms in medical equipment

#64

Post by krisoft »

flemhans wrote: post #46
sebmellen wrote: post #6

Earlier quoted context omitted.

GPWS warnings should be the gold standard for any sort of urgent audio alarm. Examples: https://www.youtube.com/watch?v=W5Z-d1Zx02o

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.

Re: Alarms in medical equipment

#65

Post by akira2501 »

unsignedint wrote: post #49
tux3 wrote: post #5

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 gen…

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 m…

> 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.

Re: Alarms in medical equipment

#66

Post by Johnny555 »

krisoft wrote: post #58
jandrese wrote: post #9

Earlier quoted context omitted.

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.

> 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 wi…

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.

Re: Alarms in medical equipment

#67

Post by throw46365 »

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.

Re: Alarms in medical equipment

#68

Post by takinola »

LorenPechtel wrote: post #4

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…

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.

Re: Alarms in medical equipment

#69

Post by nradov »

_yb2s wrote: post #50
LorenPechtel wrote: post #4

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…

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 thi…

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?

Re: Alarms in medical equipment

#70

Post by Dalewyn »

akira2501 wrote: post #65
unsignedint wrote: post #49

Earlier quoted context omitted.

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 m…

> 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…

>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

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