title: Increased blood glucose variability during therapeutic hypothermia and outcome after cardiac arrest.
abstract: OBJECTIVE
  Hypothermia impairs blood glucose homeostasis and insulin sensitivity. However, the impact of therapeutic hypothermia on blood glucose levels and insulin requirements is unknown. We analyzed blood glucose variability during therapeutic hypothermia in patients with coma after cardiac arrest and examined its impact on outcome.
  
  
  METHODS
  Prospective observational study.
  
  
  METHODS
  Two university hospital medical/surgical intensive care units.
  
  
  METHODS
  Comatose cardiac arrest patients treated with therapeutic hypothermia (33°C, 24 hrs).
  
  
  METHODS
  Insulin therapy (blood glucose target 6-8 mmol/L [110-150 mg/dL]), according to a written algorithm, with nurse-driven adjustment of insulin dose.
  
  
  RESULTS
  Two-hundred and twenty patients (median age 61 yrs, median time to return of spontaneous circulation 20 min) were studied. Two time periods, comparable in duration, were categorized: therapeutic hypothermia (stable maintenance phase) and normothermia (after rewarming). Blood glucose variability was defined as the difference between maximum and minimum blood glucose concentration during each time period. Mean blood glucose (8.3±2.3 vs. 7.1±1.3 mmol/L), blood glucose variability (5.7±3.9 vs. 3.7±3.6 mmol/L), and insulin dose (2±2 vs. 1±1 U/h) were higher during therapeutic hypothermia compared to normothermia (all p<.001). Higher mean blood glucose (7.9±1.8 mmol/L in survivors vs. 8.7±2.6 mmol/L in nonsurvivors, p=.02) and increased blood glucose variability (4.9±3.5 vs. 6.5±4.1 mmol/L, p=.003) during therapeutic hypothermia were associated with mortality. After adjusting for time to return of spontaneous circulation, initial arrest rhythm, and cardiac arrest etiology, increased blood glucose variability during therapeutic hypothermia, but not mean blood glucose level, was an independent predictor of inhospital mortality (odds ratio for death 1.10 [confidence interval 1.02-1.19], p=.016).
  
  
  CONCLUSIONS
  Mild therapeutic hypothermia is associated with higher blood glucose levels, increased blood glucose variability, and greater insulin requirements compared to the postrewarming normothermic phase. Increased blood glucose variability during therapeutic hypothermia is a predictor of inhospital mortality after cardiac arrest, independent of injury severity and mean blood glucose levels.
authors.affiliation: Department of Intensive Care Medicine, and Division of Clinical Pathophysiology, Centre Hospitalier Universitaire Vaudois, Lausanne University Hospital and Faculty of Biology and Medicine, Lausanne, Switzerland.
authors.forename: Nadine
authors.initials: N
authors.lastname: Cueni-Villoz
authors.forename: Alessandro
authors.initials: A
authors.lastname: Devigili
authors.forename: Frederik
authors.initials: F
authors.lastname: Delodder
authors.forename: Silvia
authors.initials: S
authors.lastname: Cianferoni
authors.forename: François
authors.initials: F
authors.lastname: Feihl
authors.forename: Andrea O
authors.initials: AO
authors.lastname: Rossetti
authors.forename: Philippe
authors.initials: P
authors.lastname: Eggimann
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Vincent
authors.forename: Fabio S
authors.initials: FS
authors.lastname: Taccone
authors.forename: Mauro
authors.initials: M
authors.lastname: Oddo
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001786:Blood Glucose / Q000032:analysis*; D016887:Cardiopulmonary Resuscitation / Q000379:methods*; D002985:Clinical Protocols; D003128:Coma / Q000209:etiology; D005260:Female; D017052:Hospital Mortality; D006785:Hospitals, University / Q000458:organization & administration; D006801:Humans; D007004:Hypoglycemic Agents / Q000008:administration & dosage; D007036:Hypothermia, Induced / Q000379:methods*; D007328:Insulin / Q000008:administration & dosage; D007362:Intensive Care Units / Q000458:organization & administration; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood* / Q000150:complications / Q000628:therapy*; D011446:Prospective Studies; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D007004:Hypoglycemic Agents; D007328:Insulin