AAMI and other organizations have been urging hospitals to address the problem of deaths from opioid-induced respiratory depression by installing surveillance alarm systems for all patients who are receiving opioids. But would such systems actually work? Ideally, one would perform a suitable study to investigate the issue. The objection is that such a study would be expensive and would take a long time.
But let’s use the literature to see if we can determine what would happen with such a system. AH Taenzer et al. reported the experience with their surveillance alarm system at Dartmouth. The system decreased rescue events by 2.2 per 1,000 patient days. Thus, the surveillance system detected one rescue event every 455 patient days. Dartmouth also reported that there were four alarms per patient per day. But there was only one critical event every 455 days. So in 455 days, there was one true positive alarm signal and 1,819 false positive alarm signals, for a false alarm rate of 99.95%! And even if there were one true positive alarm signal every 30 days (instead of every 455 days), with four total alarm signals per day, the rate of false alarms would still be over 99%!
And the problem is that of alarm fatigue, as was addressed in some detail at the 2011 AAMI Medical Device Alarm Summit. Indeed, groups within AAMI are working to decrease the huge number of false alarms that we have today. As Maria Cvach notes in her paper, “Monitor Alarm Fatigue: An Integrative Review”:
“When the alarm is viewed as a ‘nuisance,’ the caregiver may disable, silence, or ignore the warning that is intended to make the environment safer. Rather than creating a safer environment, a large number of nuisance alarms have an opposite effect, resulting in desensitization.”
In fact, one human factors study shows that people ignore the alarms in direct proportion to the perceived percentage of false alarms. In her paper, titled “Fewer but Better Auditory Alarms Will Improve Patient Safety,” Judy Edworthy writes that:
“If an alarm system is perceived to be 90% reliable, then people will respond slightly more than 90% of the time. If a system is perceived to be 10% reliable, then they will respond only 10% of the time. Of course, the 10% of the time that they respond to the system is probably not the 10% of the time that the system is signalling correctly, so effectively the alarm system is rendered almost useless when false alarm rates are high. The practical consequence of this is that alarms which are installed on a ‘better safe than sorry’ basis are likely to make responses to them less—rather than more—reliable.”
But the hue and cry from AAMI is that we have to “do something”! Yes, but we have to do something that will work! In 2012, The Joint Commission issued a Sentinel Event Alert on “safe use of opioids,” with several excellent steps to increase the safety of opioid use. We should push for widespread implementation of these suggestions in order to decrease the incidence of opioid-induce respiratory depression.
Do the people at AAMI who are working on the respiratory depression issue talk to the people at AAMI who are working on the alarm fatigue issue? If they were talking, they would not be recommending adding a surveillance system with more than 99% false alarms to the myriad false alarms that we have already. The respiratory depression deaths would be replaced by, or more likely augmented by, the alarm fatigue deaths.
Frank E. Block, Jr., MD, is a research professor in the Departments of Physics and Astronomy and a faculty fellow of the Vanderbilt Institute for Integrative Biosystems Research and Education at Vanderbilt University, and research professor of anesthesiology at Vanderbilt University Medical Center.