Precision Metrics for Driving Open- and Closed-Loop Resuscitation Algorithms for Enteral and IV Resuscitation in Burn Casualties

If a Soldier or patient is burned on a large portion of their body, there can be serious side effects beyond those immediately apparent on the skin. It is true that large burns have become more and more survivable in the past several decades due to improvements in care. For example, to improve the delivery of fluids (perfusion) to organs, it has become common practice to resuscitate patients by injecting liquids into the blood stream. However, upon the realization that fluids are good, many doctors started injecting excess fluids into the blood stream. Consequently, the end results were side effects that compromised health of burn victims.

Separately, it has been postulated for decades that instead of injecting fluids into the blood stream, the burn patients may be able to hydrate (and maintain organ perfusion) by drinking. Indeed the hydration approach by drinking has saved millions of lives in Third World nations due to life-threatening conditions like cholera. Recently, scientists have shown that this same approach of drinking fluid may improve urine output in burn patients, without adverse side effects. At the very least, if drinking reduced the amount of fluids into the blood stream, many of the side effects seen could be avoided. However, this possibility has not been pursued aggressively because of uncertainty or lack of knowledge regarding the response of the patients to drinking fluids orally.

To try and make treatments patient-specific, a new recommendation for amount of fluids given measures urine output. Because recording urine output hourly requires time and personnel dedication, a new computerized machine automatically monitors urine output and gives a recommendation for the rate of fluids injected into the blood stream. However, some have shown that urine output alone is not a sensitive enough marker to ensure that organs are perfused adequately. Incorporating more information about the patients' hydration status has the ability to more accurately give the right amount (not too much, not too little) fluids. This could greatly enhance the treatment of burn patients. The studies described in this proposal will use a previously established pig model of burn damage. Pigs are considered the best model for burn research due to similarities in skin healing and structure. After burn injury, we are planning to provide drinking fluids to the animals and/or injecting fluids into the blood. Furthermore, we plan to give different levels of fluids ranging from excessive to insufficient fluids. At the same time, heart activity will be measured with a very sensitive device that will be able to generate curves that describe the hydration status post-burn. In terms of hydration status curves can be generated from an electrical reading of heart activity (echocardiogram) that gives a more detailed description of the hydration status of the patient. Currently, these curves are being used to help the doctor decide how much fluid to give patients following cardiac surgery. It is a logical extension that these same curves could be used for the burn patient.

In this way, we will be able to link fluid levels and heart activity to burn-induced complications. The outcome will facilitate the identification of different types of patients that will respond to drinking fluids versus those that will respond to fluids injected into the blood. Thus, a new treatment strategy can be generated wherein both military casualties and civilian burn victims will receive the right amount of resuscitation fluids given the correct way. The ultimate goal is to achieve decreased complications which will reduce hospital stays (and therefore the cost to the healthcare system) and thus improve the quality of life for Service members and their families.