CONCLUSION
Studies have proven that therapeutic hypothermia provides cerebral protection. Therapeutic hypothermia after sudden cardiac arrest in patients who remain comatose has been shown to improve short-term neurologic recovery outcomes and survival; however, the process is not without risk. The physiologic effects of hypothermia and the alterations in pharmacokinetics of medications warrant careful consideration before implementation.
Although therapeutic hypothermia is protective after cardiac arrest, an important note is that the landmark studies discussed in this article focused on specific subgroups of patients. The studies recruited patients whose arrests were witnessed, whose initial rhythms were ventricular fibrillation or pulseless ventricular tachycardia, and who had a return of spontaneous circulation within 60 minutes. Therefore, research that examines hypothermia in larger patient populations is needed. In addition, evidence of which cooling methods provided the best, fastest, and most reliable reduction in temperature; how long a patient should be cooled; and if induced hypothermia for other types of cardiac arrest would be beneficial is lacking.
With appropriate evaluation and treatment, clinicians can make a difference in a patient's neurologic outcome after cardiac arrest. Prompt recognition of a patient's eligibility and initiation of treatment ensures a better outcome. Clinicians who care for critically ill patients are encouraged to become knowledgeable about the indications for therapeutic hypothermia and the protocols used to induce cooling in patients after cardiac arrest. jaapa
Acknowledgement: The authors would like to thank Ryan O'Gowan, PA-C, Program Director, UMass Memorial Medical Center Critical Care Physician Assistant Residency Program, for his assistance with this article.
The authors were residents in the UMass Memorial Medical Center Critical Care Physician Assistant Residency Program, Worcester, Massachusetts, at the time this article was written. They have indicated no relationships to disclose relating to the content of this article.
DRUGS MENTIONED
Cisatracurium (Nimbex)
Fentanyl (Sublimaze)
Lidocaine (Xylocaine, generics)
Meperidine (Demerol, generics)
Midazolam (Versed)
Morphine (Astramorph/PF, Duramorph, Infumorph, generics)
Pancuronium (generics)
Propofol (Diprivan)
Vecuronium (generics)
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