Multicentric study of monitoring alarms in the adult intensive care unit (ICU): a descriptive analysis

Intensive Care Med. 1999 Dec;25(12):1360-6. doi: 10.1007/s001340051082.


Objectives: To assess the relevance of current monitoring alarms as a warning system in the adult ICU.

Design: Prospective, observational study.

Settings: Two university hospital, and three general hospital, ICUs.

Patients: Hundred thirty-one patients, ventilated at admission, from different shifts (morning, evening, night) combined with different stages of stay, early (0-3 days), intermediate (4-6 days) and late (> 6 days).

Interventions: Experienced nurses were asked to record the patient's characteristics and, for each alarm event, the reason, type and consequence.

Measurements and main results: The mean age of the patients included was 59.8 +/- 16.4 and SAPS1 was 15.9 +/- 7.4. We recorded 1971 h of care. The shift distribution was 78 mornings, 85 evenings and 83 nights; the stage distribution was 88 early, 78 intermediate and 80 late. There were 3188 alarms, an average of one alarm every 37 min: 23.7% were due to staff manipulation, 17.5% to technical problems and 58.8% to the patients. Alarms originated from ventilators (37.8%), cardiovascular monitors (32.7%), pulse oximeters (14.9%) and capnography (13.5%). Of the alarms, 25.8% had a consequence such as sensor repositioning, suction, modification of the therapy (drug or ventilation). Only 5.9% of the alarms led to a physician's being called. The positive predictive value of an alarm was 27% and its negative predictive value was 99%. The sensitivity was 97% and the specificity 58%.

Conclusions: The study confirms that the level of monitoring in ICUs generates a great number of false-positive alarms.

Publication types

  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Capnography
  • Electrocardiography
  • Equipment Failure / statistics & numerical data*
  • False Positive Reactions
  • Female
  • France
  • Hospitals, General
  • Hospitals, University
  • Humans
  • Intensive Care Units / standards*
  • Intensive Care Units / statistics & numerical data
  • Length of Stay*
  • Male
  • Middle Aged
  • Monitoring, Physiologic / instrumentation*
  • Oximetry
  • Predictive Value of Tests
  • Prospective Studies
  • Respiration, Artificial
  • Safety Management / statistics & numerical data
  • Sensitivity and Specificity
  • Severity of Illness Index