Cardiac Arrest Patients, Annotated Bibliography Example

Che, D., Li, L., Kopil, C., Liu, Z., Guo, W., & Neumar, R. (2011). Impact of therapeutic hypothermia onset and duration on survival, neurologic function, and neurodegeneration after cardiac arrest. Crit. Care Med 39(6), 1423-1430.

Researchable Question: For all cardiac arrest patients, will the administration of therapeutic hypothermia or no therapeutic hypothermia be more effective in reserving neurologic function or mortality post cardiac arrest?

The authors sought to determine if post-cardiac arrest therapeutic hypothermia (TH) improves the outcome in comatose cardiac arrest survivors. The study was conducted in a university research laboratory. The participants consisted of 268 male Long Evans rats. In past animal studies, researchers have failed to use therapeutic hypothermia after cardiac arrest. In the rats used, cardiac arrest was induced by asphyxia. After 10 minutes of asphyxia, mechanical ventilation was initiated. After a successful pulse was recovered, the rates were weaned from artificial ventilation. The researchers also found that there was a therapeutic window in which intervention was more beneficial. They found that when therapy is introduced between 4 and 8 hours after ROSC the benefits are more favorable. Nevertheless, it is not known if this same window is feasible with human subjects.

One limitation of the study is the fact that the researchers are unable to determine the degree of cognitive function of the rats that respond well to the therapy. Also, the study was conducted on rats that had onset cardiac arrest due to asphyxia, so it is not known how subjects in cardiac arrest due to other causes may respond to the therapy.

About 83 percent of the rats in the study had favorable outcomes when therapy was applied within the specified window of time. The survival rate and cognitive ability of the rats that were administered therapy were much higher than rats that were not administered therapy. This is a good source to use to work on my final project because it supports my overall research question. Also, the findings support my hypothesis that therapeutic hypothermia is able to preserve the cognitive functions of cardiac arrest patients when administered within a certain window of time.