title: Time out! Is timepiece variability a factor in critical care?
abstract: BACKGROUND
  Accurate documentation of time is essential in critical care for treatments, interventions, research, and medicolegal and quality improvement activities.
  
  
  OBJECTIVE
  To assess use of timepieces in critical care and to determine practical methods for improving their accuracy.
  
  
  METHODS
  Providers were surveyed to identify timepieces used during routine and emergency care. Times displayed on standard unit and personal timepieces were compared with coordinated universal time. Four models of atomic clocks were assessed for drift for 6 weeks and for resynchronization for 1 week. Bedside monitors were manually synchronized to coordinated universal time and were assessed for drift.
  
  
  RESULTS
  Survey response was 78% (149/190). Nurses (n = 93), physicians (n = 32), and respiratory therapists (n = 24) use wall clocks (50%) and personal timepieces (46%) most frequently during emergencies. The difference from coordinated universal time was a median of -4 minutes (range, -5 minutes to +2 min) for wall clocks, -2.5 minutes (-90 minutes to -1 minute) for monitors, and 0 minutes (-22 minutes to +12 minutes) for personal timepieces. Kruskal-Wallis testing indicated significant variations for all classes of timepieces (P<.001) and for personal timepieces grouped by discipline (P=.02). Atomic clocks were accurate to 30 seconds of coordinated universal time for 6 weeks when manually set but could not be synchronized by radiofrequency signal. Drift of bedside monitors was 1 minute.
  
  
  CONCLUSIONS
  Timepieces used in critical care are highly variable and inaccurate. Manually synchronizing timepieces to coordinated universal time improved accuracy for several weeks, but the feasibility of synchronizing all timepieces is undetermined.
authors.affiliation: The Children's Hospital of Philadelphia, Philadelphia, PA, USA.
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Ferguson
authors.forename: Carey Roth
authors.initials: CR
authors.lastname: Bayer
authors.forename: Susan
authors.initials: S
authors.lastname: Fronzeo
authors.forename: Cheryl
authors.initials: C
authors.lastname: Tuckerman
authors.forename: Larissa
authors.initials: L
authors.lastname: Hutchins
authors.forename: Kathryn
authors.initials: K
authors.lastname: Roberts
authors.forename: Judy
authors.initials: J
authors.lastname: Verger
authors.forename: Vinay
authors.initials: V
authors.lastname: Nadkarni
authors.forename: Richard
authors.initials: R
authors.lastname: Lin
mesh_terms: D003422:Critical Care; D003625:Data Collection; D010348:Patient Care Team; D013995:Time; D014481:United States