Neurometric Assessment of the Effects of Analgesia

Note: The Original PI was Elisabeth Greenfield, COL, USA.

Data from previous conflicts suggest that soft tissue extremity trauma occurs in 54-75% of all casualties. Additionally, thermal injuries compromise approximately 5-10% of casualties from training accidents and conventional warfare. In the face of non conventional warfare, this number rises rapidly as a result of chemical and radiation injuries, and has been reported to be as high as 25%. Objective, physiologic assessment measurements of pain in critically ill or injured patients are both complex and difficult. Currently, the only pain assessment tools available are a measurement based on the patient's self-reported perception of pain. Multiple studies have shown that these tools produce inadequate nursing assessments of the patient's pain and therefore inadequate pain management. Previous studies have shown that both physiological and psychological outcomes have been significantly improved by eliminating or reducing pain related to injury or treatment. The purpose of this study is to develop an objective method for assessing pain in burn patients prior to, during, and immediately following wound care. We plan to develop an artificial neural network to correlate the physiological response to pain, as measured by heart rate (HR), respiratory rate (RR), blood pressure (BP), and electroencephalogram (EEG), with patient self-reported assessment of pain using a visual analogue scale (VAS). This study will address the following research questions: 1. Can a difference between an individual's brain wave activity before and after the administration of pain medication be determined?; 2. Can a difference between an individual's brain wave activity before, during, and after exposure to a painful stimulus be determined in the presence of analgesia?; 3. Is there a relationship between the individual's electrical brain wave activity and the same individual's subjective report of pain in the presence of analgesia? Design: The study consists of a prospective quasi-experimental investigation with multifactorial (HR, BP, RR, VAS, and EEG) repeated measures (preanalgesia, post analgesia, during wound care, immediately after wound care, and 15 and 30 minutes after wound care) in three groups of individuals (IV morphine sulfate, IM morphine sulfate, or oral Percocet).