Author: neuraxis_editor

Dramatic Neuronal Rescue with Prolonged Selective Head Cooling after Ischemia in Fetal Lambs
Alistair J. Gunn, Tania R. Gunn, Harmen H. de Haan, Christopher E. Williams, and Peter D. Gluckman
The American Society for Clinical Investigation, 1997

Unanesthetized near term fetal sheep were subject to 30 min of cerebral ischemia to determine whether prolonged head cooling improves outcome from severe ischemia.  Intrauterine cooling was induced by a coil around the fetal head leading to extradural temperatures of 5-10ºC and esophageal temperatures of 1.5-3ºC. Cerebral cooling reduced secondary cortical cytotoxic edema and caused a dramatic reduction in the extent of cortical infarction and neuronal loss in all regions assessed. Selective head cooling can improve neonatal outcome after perinatal asphyxia.

Mild Hypothermia and Mg++ Protect Against Irreversible Damage During CNS Ischemia
FRANCIS X. VACANTI, ADELBERT AMES III
Stroke, 1984

Spinal cord ischemia was produced in rabbits by temporary occlusion of the abdominal aorta. Recovery, or failure to recover was assessed by examining the rabbits for permanent loss of sensory and motor function in the hind limbs. A temperature reduction of 3ºC during the period of circulatory impairment caused a doubling of the duration of ischemia that could be reversibly sustained. A combination of 5 mmoles/kg of MgCl2 and the 3ºC reduction tripled the duration of ischemia that could be sustained before irreversible damage occurred.

Effect of Moderate Hypothermia on Lipid Peroxidation in Canine Brain Tissue After Cardiac Arrest and Resuscitation
Lei Baiping, Tan Xiujuan, Cai Hongwei, Xu Qiming, Guo Quling
Stroke, 1994

Twenty-one dogs were divided into four groups: group A, nonischemic controls (shams); group B, 15-minute cardiac arrest without reperfusion; group C, 15-minute cardiac arrest and standard resuscitation; and group D, 15-minute cardiac arrest and hypothermic resuscitation. All dogs in groups C and D were successfully resuscitated. In cardiac arrest group D, after 2 hours of hypothermic reperfusion, there were lower values for tissue malondialdehyde and higher values for glutathione , superoxide dismutase , and glutathione peroxidase compared with normothermic resuscitation in group C. Moderate hypothermia initiated after resuscitation can significantly help the accumulation of lipid peroxidation products and the consumption of free radical scavengers in the brain tissue.

Rapid induction of brain hypothermia by endovascular intra-arterial perfusion
Motomasa Furuse, Mark C. Preul, Yoshihiko Kinoshita, Kentaro Nishihara, Naofumi Isono and Toshihiko Kuroiwa
Neurological Research, 2007

The effects of hypothermia and circulatory arrest on cerebral blood flow and cerebral oxygen in dogs 10 dogs was studied. Dogs underwent deep hypothermia and circulatory arrest for 45 minutes. Cerebral oxygen consumption after circulatory arrest and rewarming increased by 15%. The cerebral blood flow decreased by 18% and cerebral vascular resistance increased by 8%. Surface induced hypothermia with anesthesia was tolerated by the dogs with no evidence of impairment of cerebral metabolism.