Abstract 323: High Incidence of Delirium in Survivors of Cardiac Arrest Treated with Mild Therapeutic Hypothermia
Background: Mild therapeutic hypothermia (TH) is a recommended treatment for comatose patients resuscitated from cardiac arrest. To our knowledge, the incidence of delirium and its associated risk factors has not been assessed in survivors of cardiac arrest treated with TH.
Methods: Retrospective analysis was performed on 251 consecutive comatose survivors of cardiac arrest treated with TH from 2007 to 2013 at Vanderbilt University Medical Center following sudden cardiac arrest. The incidence and duration of delirium were measured in patients who awoke from coma after cardiac arrest and survived to ICU discharge. Delirium evaluations began after TH (temp >36 degrees Celsius), and were performed at least daily using the Richmond Agitation-Sedation Scale and the Confusion Assessment Method for the ICU. A multivariable logistic regression analysis was performed to examine the effect of cardiac arrest and post-arrest management characteristics (prior to warming) on delirium duration. This model adjusted for age, APACHE II score, time to cardiopulmonary resuscitation (CPR), time from CPR to return of spontaneous circulation (ROSC), bystander CPR, initial rhythm (ventricular fibrillation/tachycardia, pulseless electrical activity/asystole), total dose of midazolam, and total dose of propofol.
Results: Of the 251 patients analyzed, 107 (43%) survived and awoke from coma; 107 (100%) of the survivors had at least one day of delirium in the ICU. The median number of delirium days was 4.0 (2.0 - 7.5 IQR). The majority of delirium was hypoactive (90%). Multivariable analysis showed that severity of illness (OR 1.77, 95% CI 1.00 - 3.15 p= 0.05) and longer times from CPR to ROSC (OR 1.53, 95% CI 1.12 - 2.09, p=0.01) were significantly associated with increased number of delirium days.
Conclusion: Delirium occurred in all survivors of cardiac arrest who awoke from coma. Efforts to prevent and treat delirium are warranted for this high-risk population, and especially for more severely ill patients and those with longer times to ROSC, who may have even longer durations of delirium.
- Therapeutic hypothermia
- Cardiac arrest
- Post cardiac arrest care
- Post cardiac resuscitation
Author Disclosures: J.S. Pollock: None. R. Hollenbeck: None. L. Wang: None. B. Holmes: None. M.N. Young: None. E.W. Ely: Honoraria; Modest; Orion, Abott, Hospira. J. Mcpherson: Consultant/Advisory Board; Modest; Velomedix. E. Vasilevskis: None.
- © 2014 by American Heart Association, Inc.