A comprehensive review of the medical literature demonstrates that cooling protects cells at risk, prevents tissue death, and preserves organ function. Therapeutic Hypothermia (TH) offers a novel solution for the protection of the body’s organs during ischemic insults and from reperfusion injury. Cooling protects cells during ischemia by reducing oxygen metabolism and inflammation and by maintaining cell membrane integrity. In the case of reperfusion injury, mild hypothermia reduces oxidative stress, microvascular clogging, free radical production, and inflammatory response, all of which are destructive to tissue that has had blood flow restored after a period of ischemia.
Hypothermia Technologies in Use or Under Investigation
- IV Saline: between 250 and 2000 ml of cold (0-5oC) saline is infused intravenously to absorb heat from the blood and surrounding tissues.
- Surface: cold pads, vests, etc are applied to both comatose and awake patients, with chilled fluids circulating through some of these devices to increase the cooling rate. A second approach involves flowing cooled water directly over the patient’s exposed skin.
- Endovascular: Venous catheter systems with circulating cold fluid are placed through a femoral insertion site and into the inferior vena cava.
- Peritoneal (Velomedix Technology): cooled fluid is circulated through a peritoneal catheter in a manner similar to that used in peritoneal dialysis.