Review Article | Published:

Hypothermia for acute brain injury—mechanisms and practical aspects

Nature Reviews Neurology volume 8, pages 214222 (2012) | Download Citation

Abstract

Hypothermia is widely accepted as the gold-standard method by which the body can protect the brain. Therapeutic cooling—or targeted temperature management (TTM)—is increasingly being used to prevent secondary brain injury in patients admitted to the emergency department and intensive care unit. Rapid cooling to 33 °C for 24 h is considered the standard of care for minimizing neurological injury after cardiac arrest, mild-to-moderate hypothermia (33–35 °C) can be used as an effective component of multimodal therapy for patients with elevated intracranial pressure, and advanced cooling technology can control fever in patients who have experienced trauma, haemorrhagic stroke, or other forms of severe brain injury. However, the practical application of therapeutic hypothermia is not trivial, and the treatment carries risks. Development of clinical management protocols that focus on detection and control of shivering and minimize the risk of other potential complications of TTM will be essential to maximize the benefits of this emerging therapeutic modality. This Review provides an overview of the potential neuroprotective mechanisms of hypothermia, practical considerations for the application of TTM, and disease-specific evidence for the use of this therapy in patients with acute brain injuries.

Key points

  • Targeted temperature management (TTM) is the most powerful mechanism of neuroprotection currently available

  • Hypothermia is proven to have clinically beneficial effects in preventing secondary brain injury in patients who have experienced cardiac arrest, and in neonates with hypoxic–ischaemic injuries

  • Cooling is an effective mechanism to reduce intracranial pressure in patients who do not respond to standard medications

  • Shivering is a common and potentially damaging adverse effect of TTM that needs to be controlled

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  1. Division of Critical Care Neurology, Room 8300, The Neurological Institute of New York, 177 Fort Washington Avenue, NY 10032, USA

    • H. Alex Choi
    • , Neeraj Badjatia
    •  & Stephan A. Mayer

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Contributions

H. A. Choi researched data for and wrote the article. N. Badjatia provided substantial contribution to discussion of the content and to review and/or editing of the manuscript before submission. S. A. Mayer provided substantial contribution to discussion of the content, and writing, review and editing of the manuscript before submission.

Competing interests

S. A. Mayer has received consulting fees from Medivance/CR Bard. N. Badjatia has received grant and research support from Cumberland Pharmaceuticals, Medivance/CR Bard and Philips. H. A. Choi declares no competing interests.

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Correspondence to Stephan A. Mayer.

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https://doi.org/10.1038/nrneurol.2012.21

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