I found this neat article on kevinmd (which despite having such a stupid name has some good stuff)
I still remember the first time I went into an operating room in second year medicine. The one thing I remember was the sepulchral quietness of the room, the sound of the ventilator bellows, the beep of the EKG monitor, the Muzak in the background and the hushed voices. If you went into any operating room today, it is a pretty good chance that at least one alarm will be going off.
I suspect that if most anaesthesiologists are like me, they spend a few minutes a day turning off as many alarms as their machine and monitors will allow. Because they are annoying and they distract you from the alarms and sounds you actually need to hear. (Actually one of my colleagues sets the alarm limits so that the alarms will go off all the time when he is working afterhours because they keep him awake.)
In 1986 when I started my residency there were very few monitors or alarms. We had an EKG, a manual blood pressure cuff and some people used a precordial or esophageal stethoscope. When we got the pulse oximeters many surgeons complained about the extra beep. (The ENT surgeons of course hated them because they showed how much patients desaturated during endoscopies). Now we have NIBPs which will alarm if the pressure is too low or high or more frequently because they can't get a reading, EKG with their alarms for high and low rates (the new monitors we bought had QT interval alarms which given that anaesthetics increase the QT, alarmed continuously until we figured out how to turn them off), ETCO2 and who knows what else.
Alarms on machines have proliferated. The first machines I used as a resident had disconnect alarms and oxygen monitors which alarmed if the FiO2 dropped below a limit. These were actually after-market devices which where added onto the basic machine which was sold with no alarms at all except for the ingenious fail-safe whistle which went on if the oxygen supply failed.
It was early in my residency that our local Centre of Excellence purchased it's first Drager machine not affectionately known as Herman. Herman had alarms for everything and gave an annoying de-da-de-da-dot over and over again. The Drager rep proudly told me that they had done research and had ascertained that this combination was the most annoying and difficult to annoy combination of sounds. Thanks guys. We are currently trialling machines at our hospital. I asked the rep if it was possible to customize alarms like cell phone ring tones. I suggested that I would like "Another One Bites the Dust". He laughed a little nervously.
Now every anaesthetic machine comes with an array of alarms for a variety of conditions. Some of them I don't even understand. There are alarms like High Inspired Gas which goes off when you are trying to do a mask induction and low MAC which goes off when you are trying to wake a patient up or doing TIVA with a little gas for your own piece of mind. When I get the alarm, I first look at the sat, the ETCO2 trace see if the patient seems to be getting anaesthetics and oxygen and then randomly make adjustments until the alarm turns itself off. To turn off or adjust the limits on many of these alarms it is necessary to hunt through multiple menus until you get to where you are at. This just distracts you from important things you could be doing like reading the paper, surfing the internet and oh yes monitoring the patient.
On top of this we have other alarms besides ours going off in the OR like the tourniquet which alarms after an OR plus on top of that we have the artificial noise from the cautery. The electrical beds our hospital recently bought emit a piercing alarm when the bed is unlocked (i.e. when you are moving a patient in or out of the OR on his bed).
We started doing endoscopy sedations about 2 years ago. After a few weeks, the supervisor came to me and asked if I could get my staff to either a) turn the alarms off or b) do something about them. The major culprit was the ETCO2 alarm attached to the nasal prongs. As I found out a few months ago when I tried using it, no matter how you set the limits it basically continuously alarms even in conscious patients whom you haven't even touched yet. Despite this our national association has made this a standard of care. I suspect the wise people who make these standards are academic anaesthesiologists who haven't given a real anaesthetic without a bevy of techs and residents to hold their hand and wipe their bum in years. Some people have advocated that the people we currently monitor on the ward with pulse oximeters should get these ETCO2 monitors instead. I can only imagine the frustration of the nurses at the false alarms generated by these machines and speculate at how long before one gets pitched thru the window.
And of course it is when the shit is actually hitting the fan that the alarms become most annoying. Like, yes I know the BP is 40/0 and I am trying to do something about it so shut the fuck up! Our recovery room nurses are forbidden to turn off or silence alarms so the odd time I bring a patient out with sats in the 80s I have to listen to the alarm until oxygen is applied and the sat comes up on its own as it mostly always does.
It would be nice if we could say that most of the alarms actually enhance patient safety. Anaesthesia is a lot safer now than when I started in 1986 and not because we have more alarms but because we have the pulse oximeter. And further it is not the cut-off point of the alarm which is important. A gradual drop in the SaO2 from 99 to 94 probably needs to be looked at and if you are going to wait for the alarm to go off at 90 you may have missed the boat. Curiously most of our pulse oximeters have a default setting of no volume on the pleth so I have to actually turn this feature on every time. Likewise a gradual trend upwards in the heart rate may indicate something sinister well before the high heart rate alarm goes off.
I am certainly not advocating returning to the state of monitoring which existed when I started my residency. I remember as an intern working with the Professor of Anaesthesia who lectured me over the whole day on how much monitoring was unnecessary and how he hardly ever put EKG electrodes on his patients (he even knew how much each one cost). It would of course be interesting to know how much we spend on EKG electrodes per event recognized and treated and I suspect it is thousands of dollars, not that I am going to give up my EKG.