A Novel Cooling Device for Targeted Brain Temperature Control and Therapeutic Hypothermia: Feasibility Study in an Animal Model

• Published in: Neurocritical care Vol. 25; no. 3; pp. 464 - 472
• Main Authors: Giuliani, E., Magnoni, S., Fei, M., Addis, A., Zanasi, R., Stocchetti, N., Barbieri, A.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.12.2016; Springer Nature B.V
• Subjects: Anesthesia; Animals; Body Temperature - physiology; Brain - blood supply; Brain Injuries, Traumatic - therapy; Cardiac arrest; Cardiovascular system; Carotid Arteries; Conductivity; Cooling; Critical Care Medicine; Feasibility Studies; Female; Heart Arrest - therapy; Heat conductivity; Heat transfer; Hypothermia; Hypothermia, Induced - instrumentation; Hypothermia, Induced - methods; Hypotheses; Intensive; Internal Medicine; Medicine; Medicine & Public Health; Metabolism; Models, Animal; Neck; Neurology; Review boards; Sensors; Sheep; Temperature; Translational Research; Stroke; Brain temperature; Traumatic brain injury; Cardiac arrest; Cooling collar; Hypothermia
• ISSN: 1541-6933; 1556-0961
• DOI: 10.1007/s12028-016-0257-7

Background Therapeutic hypothermia (i.e., temperature management) is an effective option for improving survival and neurological outcome after cardiac arrest and is potentially useful for the care of the critically ill neurological patient. We analyzed the feasibility of a device to control the temperature of the brain by controlling the temperature of the blood flowing through the neck. Methods A lumped parameter dynamic model, with one-dimensional heat transfer, was used to predict cooling effects and to test experimental hypotheses. The cooling system consisted of a flexible collar and was tested on 4 adult sheep, in which brain and body temperatures were invasively monitored for the duration of the experiment. Results Model-based simulations predicted a lowering of the temperature of the brain and the body following the onset of cooling, with a rate of 0.4 °C/h for the brain and 0.2 °C/h for the body. The experimental findings showed comparable cooling rates in the two body compartments, with temperature reductions of 0.6 (0.2) °C/h for the brain and 0.6 (0.2) °C/h for the body. For a 70 kg adult human subject, we predict a temperature reduction of 0.64 °C/h for the brain and 0.43 °C/h for the body. Conclusions This work demonstrates the feasibility of using a non-invasive method to induce brain hypothermia using a portable collar. This device demonstrated an optimal safety profile and represents a potentially useful method for the administration of mild hypothermia and temperature control (i.e., treatment of hyperpyrexia) in cardiac arrest and critically ill neurologic patients.