Cerebral Protection Using Mild Hypothermia
Brain temperatures markedly influence the consequences of cerebral
ischemia, and a mild reduction of core temperature by 1-2°C
may confer significant cerebral protection. Various studies have
shown that mild hypothermia can be beneficial for stroke patients
(lower infarct size and mortality) and febrile patients. Three primary
modes of noninvasive cooling can be employed either individually
or in combination—convective (forced air blankets), conductive
(circulating water blankets/mattresses), and evaporative. However,
the relative clinical efficacies of different methods for reducing
core body temperature have not been thoroughly studied.
In evaluating any type of cooling technique that is employed without
anesthesia, it is considered that skin warmth and thus vasodilation
must be controlled in order to avoid counter-productive shivering.
Thus, initial studies in our lab have aimed to comparatively assess
the clinical application of focal facial warming and focal hand
warming with several different cooling techniques in healthy, unanesthetized
Related articles from the lab:
- Lanier WL, Iaizzo PA, Murray MJ: The effects of convective
cooling and rewarming on systemic and central nervous system physiology
in isoflurane-anesthetized dogs. Resuscitation 23: 121-136, 1992.
- Iaizzo PA, Jeon YM, Sigg DC: Facial warming increases the
threshold for shivering. Journal of Neurosurgical Anesthesiology
11: 231-239, 1999.
- Sweney MT, Sigg DC, Tahvildari S, Iaizzo PA: Shiver suppression
using focal hand warming in unanesthetized normal subjects. Anesthesiology
95: 1089-1095, 2001.
- Pozos RS, Iaizzo PA, Danzl DF, Mills W III: Limits of tolerance
to cold. In: Handbook of Physiology: Environmental Physiology, Fregly
MJ, Blatteis CM (eds.) Oxford University Press, Chapter 25, pp.
Patents related to this research:
- US5860292: Inflatable thermal blanket for convectively cooling
a body: Augustine SD, Iaizzo PA: Issued January 19, 1999.
- US6119474: Inflatable thermal blanket for convectively and
evaporatively cooling a body. Augustine SD, Iaizzo PA: Issued September
- U6487871: Apparatus, system and method for convectively
and evaporatively cooling a body. Augustine SD, Iaizzo PA: Issued
December 3, 2002.
- US 6,581,400: Apparatus, system and method for convectively
and evaporatively cooling a head. Augustine SD, Iaizzo PA: Issued
June 24, 2003.