Neuroprotective Effects of Targeted Temperature Management

Hypothermia has a number of potential neuroprotective effects; however, they can be broken down into two main properties: metabolic and neuronal protection. When mammals hibernate, they experience acidosis both from lactate and carbon dioxide, resulting in hypoxia and hypoglycemia. These conditions are not unlike those that occur post-cardiac arrest: Hypothermia decreases metabolic rate by about 6% per 1 degree C reduction in brain temperature. If blood flow and demand are coupled, it’s possible to see a 50% decline in cerebral metabolic after cooling the brain to 32 degrees C. The protective effects occur via reduction in the early rise of calcium, decreased release of excitatory amino acids, improved cell survival signaling processes, inhibited cytochrome c release from mitochondria, decreases in free radical production and propagation, decreased lipolysis that causes salutary changes in glutamate receptor composition and signaling. The 2015 AHA Guidelines and 2015 ERC Guidelines recommend targeted temperature management (TTM) for comatose adult patients with return of spontaneous circulation (ROSC) after cardiac arrest for all rhythms and all locations of cardiac arrest.1,2 Further, they recommend selecting and maintaining a constant temperature between 32 degrees C and 36 degrees C during TTM. Absolute contraindications to TTM are an awake and responsive patient, DNR, active non-compressible bleeding and the need for immediate surgery. Relative contraindications for TTM...
Source: JEMS Patient Care - Category: Emergency Medicine Authors: Tags: Cardiac & Resuscitation Top Story Exclusive Articles Patient Care Heart of America Source Type: news