The Impact of Hyperglycemia in Burn Trauma
The first week of February marks National Burn Awareness Week. Likely all have experienced a burn at some point as it’s the leading cause of accidental injury, but far fewer have ever experienced a severe burn requiring acute care. In the United States, the CDC estimates 50,000 burn injuries require a hospital stay each year and 20,000 have burns involving more than 25% of the body. For these patients, the body’s natural healing process is not enough as burn trauma is considered one of the most severe injuries and complicated conditions.
Treating patients who have suffered burn trauma requires a multifaceted approach to meet their demanding and continuously changing needs, including managing glucose. Burns lead to a systemic response which cause many alterations in normal body functions, such as increased metabolism, alterations in cardiac function, poor fluid control and wide spread inflammation, to name only a few. All these factors can lead to hyperglycemia. The resulting hyperglycemia increases morbidity and mortality in this critically ill population (Mecott, 2010).
To recognize national burn awareness week and the impact hyperglycemia has in burn patients, here’s a review of intensive insulin therapy for burn patients:
Unique Characteristics of Burn Trauma and Challenge Presented in Managing Hyperglycemia
Managing hyperglycemia in the burn patient population can be very difficult because there are multiple physiological changes that are causing an increase in blood sugar. Burn patients are utilizing non-carbohydrate sources to generate glucose (gluconeogenesis) resulting in an increase in glucose production (glycogenolysis). These patients also have high insulin resistance, resulting in a poor response to insulin (Mecott, 2010). This abnormal production of glucose and the resistance to insulin leads to a decrease in glucose uptake and clearance from the body, resulting in hyperglycemia. Due to the extreme damage caused by burn trauma, patients can remain in a hypermetabolic and catabolic state long after the wounds have healed. Patients can remain hyperglycemic for more than six months following the burn injury and insulin resistance can linger for up to three years after the injury (Mecott, 2010).
Changing the Hyperglycemia Treatment Regime
In the past, hyperglycemia was a desired state for burn patients. More recent evidence has proven this is not true and maintaining tight glucose control in this patient population leads to better outcomes. The Van den Berghe study began the shift in treatment, targeting blood glucose values below 110 mg/dL utilizing intense insulin regimens. This study paved the way for similar studies and changed the standard of care for burn patients. As pointed out in the study, hyperglycemia can result in increased risk of infection in this very fragile patient population, who are already at an enormous risk for infection due to the lack of skin integrity resulting from the burn trauma (Van den Berghe, 2006).
Blood Glucose Target Guidelines
While there isn’t an exact target recommendation of where blood glucose levels should be maintained for the burn patient population and debate continues about the ideal glucose target range, the general consensus supports more stringent goals. Multiple studies have demonstrated that achieving target glucose levels improved skin graft survival, reduced infection, and improved survival in the severely burned patient. As a result, the practice among the majority of burn centers is to stick to relatively tight control. A study from 2008 found 73% of verified American Burn Association (ABA) centers reported target glucose of less than 120 mg/dL in a survey (Mann, 2008). Today, the latest ADA guidelines recommend a target goal range of 140 to 180 mg/dL for the majority of critically ill patients, but suggest more stringent goals, such as 110- 140 mg/dL, may be appropriate for selected patients if they can be achieved without significant hypoglycemia.
Research Supporting Intensive Insulin Therapy for Burn Patients
Stress-induced hyperglycemia, which occurs in burn patients, requires aggressive and intensive insulin treatment, and studies support this.
Mecott et al. (2010) states “for a blood glucose level of 200 mg/dL, the risk of death was found to be 2.5 times higher than for a blood glucose level of 100 mg/dL.”
Mann et al (2009) reviewed all adult patients with more than 20% total body surface burns treated with insulin infusions between 2002 and 2004. During the first 7 days of admission, patients who were considered to have better glucose control (n = 47, mean glucose 133 mg/dL) had a 45% reduction in mortality compared to patients where blood glucose targets were not obtained (n = 41, mean glucose 174 mg/dL).
Hemmila et al. (2009) was able to conclude from a study of burn patients over the course of 2 years that increased glucose management decreased the rate of pneumonia, ventilator-associated pneumonia, and urinary tract infection.
Jeschke et al (2010) was the first randomized controlled trial published that enrolled 239 burned pediatric patients and found that tight glycemic control significantly decreased infection and sepsis, improved organ function, and alleviated burn-induced insulin resistance compared with control patients.
Utilizing Technology to Manage Glucose with Presence of Burn Injury
As discussed, the management of glucose levels in the presence of a burn injury is difficult. Patient-specific therapies such as frequent high-caloric feedings and supplementation as well as stress-inducing procedures and activities need to be anticipated in order to successfully maintain glycemic control. Utilizing technology, like EndoTool, providers can standardize care and provide patient-specific therapy to adapt for changes in patient care. While EndoTool rapidly adapts therapy to changes in glucose, the software also enables providers to select clinical events to proactively anticipate a needed reduction in insulin.
With this capability, EndoTool has been shown to improve the glycemic control in burn ICU patients. A study published in the Journal of Burn Care & Research found that patients on EndoTool achieved target glucose more often compared to the paper protocol with no increased risk of hypoglycemia. They also found that nurses complied with EndoTool recommendations more often than the calculated infusion rate from the paper protocol, increasing uniformity in delivery of insulin therapy.
Overall, it is clear burn trauma is a very unique condition and managing hyperglycemia in this patient population is crucial in providing positive outcomes. As research demonstrates, with effective glycemic management, infection rates can be reduced, mortality rates can drop, and length of stay can decrease.
Hemmila, M R, Taddonio, MA, Arbabi, S., Maggio, PM, & Wahl, WL . Intensive insulin therapy is associated with reduced infectious complications in burn patients. Surgery, 2009;146(5), 966-967. doi:10.1016/j.surg.2009.03.026
Jeschke MG, Kulp GA, Kraft R, Finnerty CC, Mlcak R, Lee JO, Herndon DN. Intensive insulin therapy in severely burned pediatric patients: a prospective randomized trial. Am J Respir Crit Care Med. 2010;182(3):351–9.
Mann, EA, Mora, AG, Pidcoke, HF, Wolf, SE, & Wade, CE. Glycemic Control in the Burn Intensive Care Unit: Focus on the Role of Anemia in Glucose Measurement. Journal of Diabetes Science and Technology. 2009;3(6), 1319-1329. doi:10.1177/193229680900300612
Mann EA, Pidcoke HF, Salinas J, Holcomb JB, Wolf SE, Wade CE. The impact of intensive insulin protocols and restrictive blood transfusion strategies on glucose measurement in American Burn Association (ABA) verified burn centers. J Burn Care Res. 2008;29(5):718–723.
Mecott, GA, Al-Mousawi, AM, Gauglitz, GG, Herndon, DN, & Jeschke, MG. The Role Of Hyperglycemia In Burned Patients. Shock. 2010;33(1), 5-13. doi:10.1097/shk.0b013e3181af0494
Van den Berghe, G, Wilmer, A, Meersseman, W, Wouters, PJ, Milants, I, Van Wijngaerden, E, Bobbaers, H, & Bouillon, R. Intensive Insulin Therapy in the Medical ICU. New England Journal of Medicine. 2006;354(5):449-61.