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All-In-One Personal Protection and Cleanup Kit
This kit helps protect against direct exposure to blood, body fluids and airborne infectious disease, also containing select items for cleanup.
Recertified Lifepak 1000 AEDs
With two display options, the 1000 is easy to configure to your patient care protocols, or make changes as recommended by the American Heart Association and European Resuscitation Council.
Persys NIO - GO Intraosseous Start Kit
NIO, GO Intraosseous Start Kit, Alcohol pads, Nio Fixation, Connector, 3 Way Stop CockEasy-to-use, automatic intraosseous device which provides safe, quick and easy vascular access in emergency situations, when vascular access is needed for fluid and drug administration.
February 23, 2011
The Big Chill: Therapeutic hypothermia
Actively cooling the body's core temperature during cardiac bypass surgery has been a mainstay procedure since the 1950s. However, in the early 2000s, researchers began applying the concept of rapidly inducing hypothermia after a sudden cardiac arrest.
The first interventions used ice packs and cold saline to chill the body; today's resuscitation teams use cooling blankets and other technologies to also control the rate of cooling, maintain a constant temperature, and control the temperature rise, too.
Why does it work?
However, it is possible that the brain goes into an essentially "fail safe" mode, where metabolism dramatically slows when experiencing a sudden "no flow" state, severely reducing its need to nutrients and oxygen.
Perhaps even more dramatic, when the brain is subjected to a sudden onslaught of blood, i.e., immediately after cardiac arrest is reversed, a series of inflammatory reactions begin to destroy brain cells, rather than help them to survive.
This adverse response takes place in normal operating body temperatures; chilling the environment can minimize or perhaps even eliminate this event. Hence, therapeutic hypothermia is a real breakthrough concept in cardiac resuscitation, helping to "save the brain" after we save the heart.
How does it work?
It appears crucial that the rate of dropping the temperature is as important as the goal temperature itself. If the body is chilled too slowly, the body will attempt to generate heat through shivering, which may interfere with the cooling process.
There are newer technologies that wrap the patient with a cooling blanket, or the use of invasive cooling catheters that are inserted into the femoral vein and chilled with cold saline. Using these types of devices not only cool the patient rapidly but work more predictably than just ice packs.
Once cooling has been achieved, the patient is kept at the lower temperature for the remaining 24 hours. The patient is kept sedated and sometimes paralyzed to minimize agitation and unnecessary metabolic demands.
Critical care teams work to maintain an adequate blood pressure, normal gas levels, and minimize cardiac dysrhythmias. Toward the end of this period, the process of bringing the core temperature back to normal begins slowly. The rate of temperature rise is about 0.3 to 0.5 degrees C (0.5 to 0.9 degrees F) per hour, to about 36 degrees C (96.8 F). This process may take 8 hours or longer to complete.
There are a few side effects associated with therapeutic hypothermia; these can include bleeding as well as small risk of infection from a depressed immune system.
However, there appears to be significant benefit that outweighs the risks associated with the procedure; many cardiac centers are adopting the technique and equipment. EMS systems are working in conjunction with hospitals to begin the process in the field environment and accelerate the cooling rate.
Are there other uses?
Jess Arcure BS, MSC; Eric E Harrison MD. (2009). "Review Article of the Use of Early Hypothermia in the Treatment of Traumatic Brain Injuries." JSOM Summer 2009 Volume 10 Edition 1 10.
Schwab, S. et al. "Moderate Hypothermia in the Treatment of Patients with Severe Middle Cerebral Artery Infarction." American Heart Association. July 31, 1998, pg. 2461-2466.
Florian B, et al. (2008). "Long-term hypothermia reduces infarct volume in aged rats after focal ischemia." Neuroscience Letters 438 (2): 180–18.
The Prophylactic Hypothermia Trial to Lessen Traumatic Brain Injury (POLAR-RCT). Ongoing Clinical trial by the Australia and New Zealand Intensive Care Society, Clinical Trials Group. Retrieved 1 February 2011 http://clinicaltrials.gov/ct2/show/NCT00987688.
Dietrich, WD. (2009) Therapeutic hypothermia for spinal cord injury. Critical Care Medicine 37(7 Suppl):S238-42.
Science Daily. Optimizing Patient Outcomes After Therapeutic Hypothermia for Traumatic Brain Injury. Retrieved 12 February 2011. www.sciencedaily.com/releases/2011/01/110104114309.htm.
Yenari, MA and Hemmen, TM. (2010) Therapeutic Hypothermia for Brain Ischemia: Where Have We Come and Where Do We Go? Stroke 41:S72-S74.