Hospital records over 2.5 million patient monitor alarms in one
27 October 2014
A study of five intensive care units in the University of
California, San Francisco (UCSF), Medical Center over 31 days
recorded 2,558,760 unique alarms. Many were caused by a complex
interplay of inappropriate user settings, patients’ conditions and
computer algorithm deficiencies.
The alarms include a subset of 1,154,201 arrhythmia alarms, of
which 88.8% were false positives caused by computer algorithm
deficiencies. The data came from electrocardiogram (ECG) leads;
pressure, blood oxygen saturation and respiration waveforms; and
user settings and alarms, among other technology.
Following the study, researchers at UC San Francisco have
comprehensively defined the detailed causes as well as potential
solutions for the widespread issue of alarm fatigue in hospitals.
Their study is in the Oct 22 issue of PLOS ONE and is available
Alarm fatigue occurs when clinicians become desensitized to the
constant noise of alarms and ignore them or turn them off. Among the
numerous detrimental results are anxiety in hospital staff and
patients, sleep deprivation among hospitalized patients, and missed
life-threatening heart rhythm events.
The issue of alarm fatigue has become so significant that The
Joint Commission, a national organization that accredits hospitals,
named it a National Patient Safety Goal. This goal requires
hospitals to establish alarm safety as a priority, identify the most
important alarms and establish policies to manage alarms by January
“There have been news stories about patient deaths due to
hospital staff silencing cardiac monitor alarms and alerts from
federal agencies warning about alarm fatigue,” said senior author
Barbara Drew, PhD, RN, David Mortara Distinguished Professor in
Physiological Nursing in the School of Nursing at UCSF. “However,
there have been little data published on the topic to inform
clinicians about what to do about the problem. Our study is the
first to shed light on cardiac monitor alarm frequency, accuracy,
false alarm causes and strategies to solve this important clinical
Based on these findings and earlier studies, the researchers
suggest that medical devices focus on using all available ECG leads
to identify the non-disruptive leads and the leads with adequate QRS
waveform amplitude. These devices also should provide prompts to aid
in more appropriate tailoring of alarm settings to individual
patients. And, atrial fibrillation alarms should be limited to new
onset and termination of the arrhythmia, with delays for ST-segment
and other parameter alarms able to be configured.
“Nurses and patients are barraged by a staggering number of
monitor alarms that could be resolved by improved computer
algorithms,” Drew said. “Our results shed light on the high
prevalence of alarms that are mostly false and provide insights into
the causes of so many false alarms, along with suggestions for
Drew and her colleagues anticipate their study will be cited by
current working groups attempting to solve alarm fatigue, led by The
Joint Commission, the Association for the Advancement of Medical
Instrumentation (AAMI), the International Society for Computerized
Electrocardiology (ISCE), the Emergency Care Research Institute
(ERCI), the American Heart Association, and the U.S. Food & Drug
Administration (FDA) Center for Radiological Devices & Health.
“Because computer devices are more reliable than humans, an
opportunity exists to improve physiologic monitoring and reduce
alarm fatigue,” the authors write.