Bad data: When everyone breathes at the same rate

It was my second day of residency, and something was afoot. As I made my way around my first rotation on the cardiac floor, my medical senses were tingling. There was something strange happening to all of my patients, I saw. As I peaked over my cohort’s shoulders, I secretly saw that it was happening to their patients too, though they hadn’t seemed to notice.

Only I did, and I was going to report it to my senior. Together we were going to report it to the New England Journal of Medicine, and I was going to win the Nobel Prize of awesome doctors. Yes, I alone noticed that all of the patients on the floor were somehow inexplicably breathing at the exact same respiratory rate. Not only this, but they were breathing fast, at a rate of 20, clearly something must be causing all of them to do this. Surely this could not have been due to documentation error, since all the of the other vital signs seemed to vary, it was only the respiratory rates which seemed to stay the same among all the patients.

That day was more than 10 years distant, I still don’t have my Nobel Prize, and the NEJM isn’t returning my calls. The answer to the question that I posed back then about a phenomenon I now see daily is only too easy to find. It sits in every hospital ward, at the end of the hallway. There a bank of mobile machines that is wheeled around the ward to check vital signs sits recharging in wall outlets. As nurses and assistants scramble to administer medications, change bedsheets, turn patients, answer call lights, help patients around the halls, answer the phones, answer family questions, speak with clinicians, and pass food trays, they wheel these devices to their patients’ bedside.

They quickly first attach a blood pressure cuff and press the cycle button. As the cuff inflates, they attach a finger sat monitor from the same machine which takes a few seconds to get a reading. As this is taking a reading, they ask the patient to open their mouth and insert a temperature probe to get a temperature. Around this time, the BP cuff says “error,” so they cycle it once more. While this cycles, they now have a reading for temperature, and the finger monitor gives them readings for oxygen saturation and heart rate.

They have a few paper towels left over from feeding the patient in the next bed, so they start jotting down numbers in it, and just as they finish this, they get a reading from the BP cuff, which they write down as well. They would like to put this in the computer right away, but in the hallway call light buzzers are sounding, somebody wants to get up. Another person wants their pain medications, the radiology suite wants the patient in the next bed sent for their ultrasound immediately. But wait, aren’t they supposed to be fasting for that test? And there’s 4 more patients who need to have their vital signs checked.

So several moments later, as the nurse finally sits down to enter all the vital signs into the chart, values will be entered for heart rate, blood pressure, temperature, oxygen saturation. But since no respiratory rate was checked, the default number of 18 or 20 is often entered. Why is the respiratory rate not checked?

Because the vital signs machine does not check respiratory rate.

The measurement of the respiratory rate, it turns out, is still an old fashioned vital sign. It requires a person to stay at the bedside for at least 30 seconds and manually count the patient’s respirations. Put simply, it is an analog measurement in a digital, multi-tasking age.

In a recent issue of Chest, this phenomenon was highlighted in a unique study. While this is not the first time this issue has been brought to light, what was unique was the manner in which the authors did so. They took a uniquely modern phenomenon, the flash mob, and used it to highlight the degree of the problem. A flash mob, as Wikipedia describes it, is “a group of people who assemble suddenly in a public place, perform an unusual and seemingly pointless act for a brief time, then quickly disperse, often for the purposes of entertainment, satire, and artistic expression.”

Add scientific research to that list of purposes.

The flash mob, made up of medicine residents, noted what had been recorded as the patients vital signs, then checked vital signs themselves, including the respiratory rate. They found little variation between the documented vital signs and their own measurements, other than of course, respiratory rate, which was documented by nurses as 18 or 20 most of the time.

This again highlights a common problem: RN’s and LPN’s do not have have the technology they need to make the measurements they need, and the result is bad data. How is it that such a thing could occur in this digital age? Surely it begs the question WWETD (What would Eric Topol Do?)

In the coming cataclysm of meaningful use, pay for performance, and data mining, data points like these are going to be used to drive interventions and show outcomes. It is going to be incredibly important that we get things like input of basic patient data right. And it shouldn’t take a flash mob of people to get it.

On another note, I admire the authors of this study for showing us a new way to conduct research. The use of the flash mob approach was genius for several reasons. It involved a residency program and got young doctors excited about research, hospital processes, and quality improvement. It allowed the data collection to be completed in a matter of minutes, therefore the subjects did not have time to alter behavior. And perhaps most importantly, it led to the term “flash mob” being published in the title of a major medical journal.

And so it is for all these reasons that I would like personally extend my gratitude to the authors and hereby nominate them for the Nobel Prize of awesome doctors.

Deep Ramachandran is a pulmonary and critical care physician who blogs at CaduceusBlog.  He can be reached on Twitter @Caduceusblogger.

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