Auditory alarms during anesthesia monitoring with an integrated monitoring system

Int J Clin Monit Comput. 1996 May;13(2):81-4. doi: 10.1007/BF02915842.


Alarms in the operating room remain a major source of annoyance and confusion. A previous study by Kestin et al. utilized a specific combination of distinct, separate monitors in 50 pediatric patients. He reported a mean of 10 alarms per case with a mean frequency of one alarm every 4.5 minutes. The alarms were classified as spurious (75%), change outside the alarm limits (22%), or patient risk (3%). We performed a similar study with 50 adult patients under general anesthesia with default alarm settings on an integrated monitor, (Cardiocap, Datex, Helsinki). In our study, the number of alarms averaged 3 per case with a mean frequency of one every 34 minutes. Spurious alarms (those caused by electrocautery, accidental patient movement, or other non-physiological reasons) represented only 24% of all alarms. Those alarms sounding that were outside the limits occurred at a rate of 53%, and those that were considered patient risks occurred at a rate of 23%. Of the alarms, 67% occurred during the beginning and end of anesthesia. The end-tidal carbon dioxide accounted for 42% of the alarms, mostly during intubation and extubation. Suggestions are made for further improvement in alarm systems.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Anesthesiology / instrumentation*
  • Equipment Failure
  • Humans
  • Monitoring, Intraoperative / instrumentation*
  • Systems Integration*