title: Delayed time to defibrillation after in-hospital cardiac arrest.
abstract: BACKGROUND
  Expert guidelines advocate defibrillation within 2 minutes after an in-hospital cardiac arrest caused by ventricular arrhythmia. However, empirical data on the prevalence of delayed defibrillation in the United States and its effect on survival are limited.
  
  
  METHODS
  We identified 6789 patients who had cardiac arrest due to ventricular fibrillation or pulseless ventricular tachycardia at 369 hospitals participating in the National Registry of Cardiopulmonary Resuscitation. Using multivariable logistic regression, we identified characteristics associated with delayed defibrillation. We then examined the association between delayed defibrillation (more than 2 minutes) and survival to discharge after adjusting for differences in patient and hospital characteristics.
  
  
  RESULTS
  The overall median time to defibrillation was 1 minute (interquartile range, <1 to 3 minutes); delayed defibrillation occurred in 2045 patients (30.1%). Characteristics associated with delayed defibrillation included black race, noncardiac admitting diagnosis, and occurrence of cardiac arrest at a hospital with fewer than 250 beds, in an unmonitored hospital unit, and during after-hours periods (5 p.m. to 8 a.m. or weekends). Delayed defibrillation was associated with a significantly lower probability of surviving to hospital discharge (22.2%, vs. 39.3% when defibrillation was not delayed; adjusted odds ratio, 0.48; 95% confidence interval, 0.42 to 0.54; P<0.001). In addition, a graded association was seen between increasing time to defibrillation and lower rates of survival to hospital discharge for each minute of delay (P for trend <0.001).
  
  
  CONCLUSIONS
  Delayed defibrillation is common and is associated with lower rates of survival after in-hospital cardiac arrest.
authors.affiliation: Saint Luke's Mid-America Heart Institute, Kansas City, MO 64111, USA. pchan@cc-pc.com
authors.forename: Paul S
authors.initials: PS
authors.lastname: Chan
authors.forename: Harlan M
authors.initials: HM
authors.lastname: Krumholz
authors.forename: Graham
authors.initials: G
authors.lastname: Nichol
authors.forename: Brahmajee K
authors.initials: BK
authors.lastname: Nallamothu
mesh_terms: D000368:Aged; D015897:Comorbidity; D004554:Electric Countershock; D005260:Female; D006323:Heart Arrest / Q000209:etiology / Q000401:mortality / Q000628:therapy*; D006333:Heart Failure / Q000150:complications; D006742:Hospital Bed Capacity; D017052:Hospital Mortality; D006760:Hospitalization; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000150:complications; D012189:Retrospective Studies; D016019:Survival Analysis; D017180:Tachycardia, Ventricular / Q000150:complications; D013997:Time Factors; D014693:Ventricular Fibrillation / Q000150:complications