title: Intra-operative monitoring--many alarms with minor impact.
abstract: Alarms are key components of peri-operative monitoring devices, but a high false-alarm rate may lead to desensitisation and neglect. The objective of this study was to quantify the number of alarms and assess the value of these alarms during moderate-risk surgery. For this purpose, we analysed documentation of anaesthesia workstations during 38 surgical procedures. Alarms were classified on technical validity and clinical relevance. The median (IQR [range]) alarm density per procedure was 20.8 (14.5-34.2 [3.7-85.6]) alarms.h⁻¹ (1 alarm every 2.9 min) and increased during induction and emergence of anaesthesia, with up to one alarm per 0.99 min during these periods (p < 0.001). Sixty-four per cent of all alarms were clinically irrelevant, whereas 5% of all alarms required immediate intervention. The positive predictive value of an alarm during induction and emergence was 20% (95% CI 16-24%) and 11% (95% CI 8-14%), respectively. This study shows that peri-operative alarms are frequently irrelevant, with a low predictive value for an emerging event requiring clinical intervention.
authors.affiliation: Anaesthesiology Department, V.U. University Medical Centre/Institute for Cardiovascular Research, Amsterdam, the Netherlands.
authors.forename: F R
authors.initials: FR
authors.lastname: de Man
authors.forename: S
authors.initials: S
authors.lastname: Greuters
authors.forename: C
authors.initials: C
authors.lastname: Boer
authors.forename: D P
authors.initials: DP
authors.lastname: Veerman
authors.forename: S A
authors.initials: SA
authors.lastname: Loer
mesh_terms: D000758:Anesthesia; D000762:Anesthesia Recovery Period; D056902:Clinical Alarms; D003627:Data Interpretation, Statistical; D004868:Equipment Failure; D005189:False Positive Reactions; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D007260:Infusion Pumps; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000295:instrumentation*; D011237:Predictive Value of Tests; D012122:Ventilators, Mechanical; D014741:Video Recording