Background: Sepsis and septic shock occur commonly in severe burns. Acute kidney injury (AKI) is also common and often results as a consequence of sepsis. Mortality is unacceptably high in burn patients who develop AKI requiring renal replacement therapy and is presumed to be even higher when combined with septic shock. We hypothesized that high-volume hemofiltration (HVHF) as a blood purification technique would be beneficial in this population. Methods: We conducted a multicenter, prospective, randomized, controlled clinical trial to evaluate the impact of HVHF on the hemodynamic profile of burn patients with septic shock and AKI involving seven burn centers in the United States. Subjects randomized to the HVHF were prescribed a dose of 70 ml/kg/hour for 48 hours while control subjects were managed in standard fashion in accordance with local practices.

Early nutritional support is an essential component of burn care to prevent ileus, stress ulceration, and the effects of hypermetabolism. The American Burn Association practice guidelines state that enteral feedings should be initiated as soon as practical. The authors sought to evaluate compliance with early enteral nutrition (EN) guidelines, associated complications, and hospitalization outcomes in a prospective multicenter observational study. They conducted a retrospective review of mechanically ventilated burn patients enrolled in the prospective observational multicenter study “Inflammation and the Host Response to Injury.” Timing of initiation of tube feedings was recorded, with early EN defined as being started within 24 hours of admission. Univariate and multivariate analyses were performed to distinguish barriers to initiation of EN and the impact of early feeding on development of multiple organ dysfunction syndrome, infectious complications, days on mechanical ventilation, intensive care unit (ICU) length of stay, and survival. A total of 153 patients met study inclusion criteria. The cohort comprised 73% men, with a mean age of 41 ± 15 years and a mean %TBSA burn of 46 ± 18%. One hundred twenty-three patients (80%) began EN in the first 24 hours and 145 (95%) by 48 hours. Age, sex, inhalation injury, and full-thickness burn size were similar between those fed by 24 hours vs after 24 hours, except for higher mean Acute Physiology and Chronic Health Evaluation II scores (26 vs 23, P = .03) and smaller total burn size (44 vs 54% TBSA burn, P = .01) in those fed early. There was no significant difference in rates of hyperglycemia, abdominal compartment syndrome, or gastrointestinal bleeding between groups. Patients fed early had shorter ICU length of stay (adjusted hazard ratio 0.57, P = 0.03, 95% confidence interval 0.35–0.94) and reduced wound infection risk (adjusted odds ratio 0.28, P = 0.01, 95% confidence interval 0.10–0.76). The investigators have found early EN to be safe, with no increase in complications and a lower rate of wound infections and shorter ICU length of stay. Across institutions, there has been high compliance with early EN as part of the standard operating procedure in this prospective multicenter observational trial. The investigators advocate that initiation of EN by 24 hours be used as a formal recommendation in nutrition guidelines for severe burns, and that nutrition guidelines be actively disseminated to individual burn centers to permit a change in practice.

The incidence and prognosis of acute kidney injury (AKI) developing during acute resuscitation have not been well characterized in burn patients. The recently developed Risk, Injury, Failure, Loss, and End-stage (RIFLE) classification provides a stringent stratification of AKI severity and can allow for the study of AKI after burn injury. We hypothesized that AKI frequently develops early during resuscitation and is associated with poor outcomes in severely burned patients. We conducted a retrospective review of patients enrolled in the prospective observational multicenter study “Inflammation and the Host Response to Injury.” A RIFLE score was calculated for all patients at 24 hours and throughout hospitalization. Univariate and multivariate analyses were performed to distinguish the impact of early AKI on progressive renal dysfunction, need for renal replacement therapy, and hospital mortality. A total of 221 adult burn patients were included, with a mean TBSA burn of 42%. Crystalloid resuscitation averaged 5.2 ml/kg/%TBSA, with urine output of 1.0 ± 0.6 ml/kg/hr at 24 hours. Sixty-two patients met criteria for AKI at 24 hours: 23 patients (10%) classified as risk, 32 patients (15%) as injury, and 7 (3%) as failure. After adjusting for age, TBSA, inhalation injury, and nonrenal Acute Physiology and Chronic Health Evaluation II ≥20, early AKI was associated with an adjusted odds ratio 2.9 for death (95% CI 1.1–7.5, P = .03). In this cohort of severely burned patients, 28% of patients developed AKI during acute resuscitation. AKI was not always transient, with 29% developing progressive renal deterioration by RIFLE criteria. Early AKI was associated with early multiple organ dysfunction and higher mortality risk. Better understanding of how early AKI develops and which patients are at risk for progressive renal dysfunction may lead to improved outcomes.

Inhalation injury is associated with severe pulmonary complications as inhaled products of combustion cause lung inflammation and loss of natural defenses. A bronchoscopic grading for inhalation injury has been proposed but has not yet been validated in burn patients. In this study, the authors evaluated whether bronchoscopic grading of injury clinically correlated with indices of gas exchange over the first 72 hours or predicted differences in hospitalization outcomes. They conducted a single-center retrospective review of all mechanically ventilated adults with suspected inhalation injury and thermal injury over an 18-month period. All recorded bronchoscopy examinations were reviewed and categorized injury according to the published abbreviated injury score (AIS 0: no injury, 1: mild, 2: moderate, 3: severe, and 4: massive injury). They also compared changes in oxygenation, airway pressures, chest radiograph findings, fluid administration, and early development of pneumonia and organ failure, by severity of inhalation injury according to the AIS. Thirty-two adult patients met inclusion criteria over the study period. This cohort was 69% male with a mean age of 44.5 ± 14 years and a mean % TBSA burn of 33.9 ± 17%. Of these 32 patients, 11 patients (34%) were classified as grade 0, 9 patients (28%) were classified as grade 1, 7 patients (22%) were classified as grade 2, and 5 patients (16%) were classified as grade 3. Measured carboxyhemoglobin levels increased significantly with higher AIS grade. Oxygenation indices were worse as grade worsened by 24, 48, and 72 hours. The incidence of acute respiratory distress syndrome increased by grade of injury: 0, 22, 57, and 80%, respectively, at 24 hours (P < .01), and remained statistically different at 48 and 72 hours. After adjustment for age, % TBSA burn, and full-thickness component, severe inhalation injury (grades 2 and 3) was associated with an increased risk of acute respiratory distress syndrome at 24 and 72 hours, as well as ventilator days >21 days, and a trend toward multiple organ dysfunction syndrome and mortality. Better understanding of the relationship between inhalation injury and lung physiologic sequelae is a burn research priority. The bronchoscopic grading of inhalation injury moderately correlates with early indices of impaired gas exchange in this cohort and may be a promising tool for staging lower airway injury. Prospective studies should definitively answer whether AIS bronchoscopy staging predicts hospitalization outcomes in inhalation injury.