title: Intensive nursing work schedules and the risk of hypoglycaemia in critically ill patients who are receiving intravenous insulin.
abstract: BACKGROUND
  Nurses in the intensive care unit (ICU) commonly work frequent 12 h shifts, potentially leading to fatigue and reduced vigilance. The authors hypothesised that rates of hypoglycaemia in patients receiving an insulin infusion would be associated with the intensity of work of the bedside nurse in the preceding 72 h.
  
  
  METHODS
  The authors identified ICU patients who had hypoglycaemia (glucose ≤3.5 mmol/l, 63 mg/dl) between October 2006 and June 2007. The number of shifts worked in the previous 72 h was calculated for the nurse caring for the patient when the event occurred (case shift). For each case shift, the authors identified up to three control shifts (24, 48 and 72 h before the event in the same patient) and calculated the number of shifts worked by nurses on these shifts in the previous 72 h. Conditional logistic regression was used to determine whether the number of shifts worked was associated with hypoglycaemia.
  
  
  RESULTS
  There were 41 events (32 patients). Each additional shift worked in the previous 72 h was associated with a significantly increased risk of hypoglycaemia (OR = 1.65/shift, 95% CI 1.01 to 2.68, p = 0.04) after controlling for nurse age and experience. The association was greater for the 23 events associated with an error in management according to the insulin protocol (OR = 2.93/shift, 1.15 to 7.44, p = 0.02) compared with events not associated with an error (OR = 1.34/shift, 0.73 to 2.45, p = 0.34).
  
  
  CONCLUSIONS
  Intensive nursing work schedules are associated with hypoglycaemic events in ICU patients.
authors.affiliation: Providence Health Care, University of British Columbia, Vancouver, Canada.
authors.forename: Kimberley
authors.initials: K
authors.lastname: Louie
authors.forename: Rupi
authors.initials: R
authors.lastname: Cheema
authors.forename: Peter
authors.initials: P
authors.lastname: Dodek
authors.forename: Hubert
authors.initials: H
authors.lastname: Wong
authors.forename: Amanda
authors.initials: A
authors.lastname: Wilmer
authors.forename: Maja
authors.initials: M
authors.lastname: Grubisic
authors.forename: John Mark
authors.initials: JM
authors.lastname: Fitzgerald
authors.forename: Najib T
authors.initials: NT
authors.lastname: Ayas
mesh_terms: D000328:Adult; D000368:Aged; D001955:British Columbia; D016638:Critical Illness; D006801:Humans; D007003:Hypoglycemia / Q000209:etiology*; D007004:Hypoglycemic Agents / Q000008:administration & dosage*; D007262:Infusions, Intravenous; D007328:Insulin / Q000008:administration & dosage*; D007362:Intensive Care Units; D008875:Middle Aged; D009741:Nursing Staff, Hospital / Q000523:psychology / Q000592:standards; D010561:Personnel Staffing and Scheduling / Q000458:organization & administration*; D018570:Risk Assessment; D000078329:Workforce
chemical_list: D007004:Hypoglycemic Agents; D007328:Insulin