Christopher E. White

Haemodynamically unstable pelvic fractures

Bleeding pelvic fractures that result in haemodynamic instability have a reported mortality rate as high as 40%. Because of the extreme force needed to disrupt the pelvic ring, associated injuries are common and mortality is usually from uncontrolled haemorrhage from extra-pelvic sources. Identifying and controlling all sources of bleeding is a complex challenge and is best managed by a multi-disciplinary team, which include trauma surgeons, orthopaedic surgeons and interventional radiologists. Once the pelvis is identified as the major source of haemorrhage, component therapy reconstituting whole blood should be used and the pelvic region wrapped circumferentially with a sheet or pelvic binder. Patients at risk for arterial bleeding who continue to show haemodynamic instability despite resuscitative efforts should undergo immediate arteriography and embolisation of bleeding pelvic vessels. If this is unavailable or delayed, or the patient has other injuries (i.e., head, chest, intra-abdominal, long bone), external fixation and pelvic packing, performed concomitantly with other life-saving procedures, may be used to further reduce pelvic venous bleeding. If however, the patient remains haemodynamically labile without apparent source of blood loss, transcatheter angiographic embolisation should be attempted to locate and stop pelvic arterial bleeding. Institutional practice guidelines have been shown to reduce mortality and should be developed by all centres treating pelvic fractures.

High-frequency percussive ventilation and low tidal volume ventilation in burns: a randomized controlled trial.

Objectives:In select burn intensive care units, high-frequency percussive ventilation is preferentially used to provide mechanical ventilation in support of patients with acute lung injury, acute respiratory distress syndrome, and inhalation injury. However, we found an absence of prospective studies comparing high-frequency percussive ventilation with contemporary low-tidal volume ventilation strategies. The purpose of this study was to prospectively compare the two ventilator modalities in a burn intensive care unit setting. Design:Single-center, prospective, randomized, controlled clinical trial, comparing high-frequency percussive ventilation with low-tidal volume ventilation in patients admitted to our burn intensive care unit with respiratory failure. Setting:A 16-bed burn intensive care unit at a tertiary military teaching hospital. Patients:Adult patients ≥18 yrs of age requiring prolonged (>24 hrs) mechanical ventilation were admitted to the burn intensive care unit. The study was conducted over a 3-yr period between April 2006 and May 2009. This trial was registered with ClinicalTrials.gov as NCT00351741. Interventions:Subjects were randomly assigned to receive mechanical ventilation through a high-frequency percussive ventilation-based strategy (n = 31) or a low-tidal volume ventilation-based strategy (n = 31). Measurements and Main Results:At baseline, both the high-frequency percussive ventilation group and the low-tidal volume ventilation group had similar demographics to include median age (interquartile range) (28 yrs [23–45] vs. 33 yrs [24–46], p = nonsignificant), percentage of total body surface area burn (34 [20–52] vs. 34 [23–50], p = nonsignificant), and clinical diagnosis of inhalation injury (39% vs. 35%, p = nonsignificant). The primary outcome was ventilator-free days in the first 28 days after randomization. Intent-to-treat analysis revealed no significant difference between the high-frequency percussive ventilation and the low-tidal volume ventilation groups in mean (± sd) ventilator-free days (12 ± 9 vs. 11 ± 9, p = nonsignificant). No significant difference was detected between groups for any of the secondary outcome measures to include mortality except the need for “rescue” mode application (p = .02). Nine (29%) in the low-tidal volume ventilation arm did not meet predetermined oxygenation or ventilation goals and required transition to a rescue mode. By contrast, two in the high-frequency percussive ventilation arm (6%) required rescue. Conclusions:A high-frequency percussive ventilation-based strategy resulted in similar clinical outcomes when compared with a low-tidal volume ventilation-based strategy in burn patients with respiratory failure. However, the low-tidal volume ventilation strategy failed to achieve ventilation and oxygenation goals in a higher percentage necessitating rescue ventilation.

Comparison Between Civilian Burns and Combat Burns From Operation Iraqi Freedom and Operation Enduring Freedom

Objective:To assess outcome differences between locally burned civilians and military personnel burned in a distant combat zone treated in the same facility. Summary Background Data:The United States Army Institute of Surgical Research (USAISR) Burn Center serves as a referral center for civilians and is the sole center for significant burns in military personnel. We made the hypothesis that outcomes for military personnel burned in the current conflict in Iraq and Afghanistan would be poorer because of delays to definitive treatment, other associated injury, and distance of evacuation. Methods:We reviewed the civilian and military records of patients treated at the USAISR from the outset of hostilities in Iraq in April 2003 to May 2005. Demographics, injury data, mortality, and clinical outcomes were compared. Results:We cared for 751 patients during this time period, 273 of whom were military (36%). Military injuries occurred in a younger population (41 ± 19 vs. 26 ± 7 years for civilian and military respectively, P < 0.0001) with a longer time from injury to burn center arrival (1 ± 5 days vs. 6 ± 5, P < 0.0001), a higher Injury Severity Score (ISS 5 ± 8 vs. 9 ± 11, P < 0.0001), and a higher incidence of inhalation injury (8% vs. 13%, P = 0.024). Total burn size did not differ. Mortality was 7.1% in the civilian and 3.8% in the military group (P = 0.076). When civilians outside the age range of the military cohort were excluded, civilian mortality was 5.0%, which did not differ from the military group (P = 0.57). Total body surface area (TBSA) burned, age ≥40 years, presence of inhalation injury, and ventilator days were found to be important predictors of mortality by stepwise regression, and were used in a final predictive model with the area under receiver operator characteristic curve of 0.97 for both populations considered together. No significant effect of either group was identified during development. Conclusions:Mortality does not differ between civilians evacuated locally and military personnel injured in distant austere environments treated at the same center.

Evolution of burn resuscitation in operation Iraqi freedom.

Abstract : Burns are common in all military conflicts, comprising approximately 10% of all casualties. Of these, nearly 20% are categorized as severe, or involving greater than 20% TBSA, and require significant intravenous resuscitation. A unique set of challenges have emerged during the present conflict associated with global evacuation of burned soldiers, adding a new dimension to the already complex and often-controversial topic of the burn resuscitation. Critical advances in air evacuation of the war wounded, thorough prewar planning, and sustained burn care education of deployed personnel have proven vital in the optimal care of our injured soldiers. During the Vietnam conflict, burned soldiers were evacuated to an Army Hospital in Japan (Camp Zama) and were treated for up to 6 months before they were evacuated to the United States. Since that time, the transfer of the patient to the burn center for definitive care has been expedited by the Army Burn Flight Teams ability to transport the most severely burned patients within the first several days after injury. With the emergence of the U.S. Air Force Critical Care Air Transport Team (CCATT) program in the 1990s, global air evacuation of burn patients became even more rapid, maximizing available U.S. Air Force aircraft for patient evacuation. The doctrine has shifted from aeromedical transport of the stable to aeromedical transport of the stabilized. In burn patients, evacuation presents a unique problem because it usually takes place while resuscitation in the first 24 to 48 hours after burn injury is ongoing. In addition to the innate complexity involved in global evacuation, war burn patients often exhibit multisystem traumatic injuries further complicating and augmenting resuscitation fluid needs above and beyond standard burn resuscitation formulas. The presence of smoke inhalation injury, occurring in 5% to 15% of patients with severe burns, also increases fluid requirements.

Continuous venovenous hemofiltration in severely burned patients with acute kidney injury: a cohort study

IntroductionAcute kidney injury (AKI) is a common and devastating complication in critically ill burn patients with mortality reported to be between 80 and 100%. We aimed to determine the effect on mortality of early application of continuous venovenous hemofiltration (CVVH) in severely burned patients with AKI admitted to our burn intensive care unit (BICU).MethodsWe performed a retrospective cohort study comparing a population of patients managed with early and aggressive CVVH compared with historical controls managed conservatively before the availability of CVVH. Patients with total body surface area (TBSA) burns of more than 40% and AKI were treated with early CVVH and their outcomes compared with a group of historical controls.ResultsOverall, the 28-day mortality was significantly lower in the CVVH arm (n = 29) compared with controls (n = 28) (38% vs. 71%, P = 0.011) as was the in-hospital mortality (62% vs. 86%, P = 0.04). In a subgroup of patients in shock, a dramatic reduction in the pressor requirement was seen after 24 and 48 hours of treatment. Compared with controls (n = 19), significantly fewer patients in the CVVH group (n = 21) required vasopressors at 24 hours (100% vs 43%, P < 0.0001) and at 48 hours (94% vs 24%, P < 0.0001). In those with acute lung injury (ALI)/acute respiratory distress syndrome (ARDS), there was a significant increase from baseline in the partial pressure of arterial oxygen (PaO2) to fraction of inspired oxygen (FiO2) ratio at 24 hours in the CVVH group (n = 16, 174 ± 78 to 327 ± 122, P = 0.003) but not the control group (n = 20, 186 ± 64 to 207 ± 131, P = 0.98).ConclusionsThe application of CVVH in adult patients with severe burns and AKI was associated with a decrease in 28-day and hospital mortality when compared with a historical control group, which largely did not receive any form of renal replacement. Clinical improvements were realized in the subgroups of patients with shock and ALI/ARDS. A randomized controlled trial comparing early CVVH to standard care in this high-risk population is planned.

Advances in surgical care: Management of severe burn injury

Background:Management of combat casualties with severe burns and associated traumatic injuries requires a coordinated interaction of surgical, critical care, and evacuation assets. These patients present enormous challenges to the entire medical system as a result of the severity of injury combined with the great distance required for transport to definitive care. Objective:The objective of this study was to review and highlight some of the advances in burn critical care experienced during recent combat operations. This review focuses on initial resuscitation, respiratory support, care of the burn wound, and long range evacuation. Data Source:The authors conducted a search of the MEDLINE database and manual review of published articles and abstracts from national and international meetings in addition to Institute of Surgical Research Burn Center registry. Conclusions:Fluid resuscitation during the first 24 to 48 hrs after injury remains a significant challenge for all who manage burn casualties. Guidelines have been developed in an effort to standardize fluid resuscitation during this time. These guidelines along with the standardization of burn wound care and continued provider education have resulted in decreased morbidity and mortality in severely burned patients returning from war zones. This system of care for severely burned patients facilitates the transfer of the burn casualty between healthcare providers and facilities and is now being integrated into the catchment area for the Institute of Surgical Research Burn Center.

Impact of policy change on US Army combat transfusion practices.

BACKGROUND Clinical practice guidelines (CPGs) are used to keep providers up-to-date with the most recent literature and to guide in decision making. Adherence is typically improved although many have a muted impact. In March 2006, the US Army issued a damage control resuscitation CPG, encouraging 1:1 plasma:red blood cell (RBC) transfusions and limiting crystalloid use. The objective of this study was to determine whether the CPG was associated with a change in the transfusion practices in combat-wounded patients. METHODS All US service members injured in Operation Iraqi Freedom/Operation Enduring Freedom who received massive transfusions (MTs; > or = 10 RBC in 24 hours) were queried from the US Army Institute of Surgical Research transfusion database. Whole blood, when used, was counted as 1 unit of RBC, fresh frozen plasma (FFP), and platelet. Subjects were divided into pre- and post-CPG cohorts. Primary outcomes were ratios of FFP:RBC and crystalloid use. RESULTS A total of 777 MT patients were identified. The cohorts were similar in age (25 years +/- 6 years vs. 25 years +/- 6 years; p = ns) and injury severity scale score (24 +/- 12 vs. 25 +/- 12; p = ns). The post-CPG cohort was warmer (96.5 degrees F +/- 7.8 degrees F vs. 98.2 degrees F +/- 1.9 degrees F; p < 0.05) and was transfused more RBC, platelets, and plasma but received less crystalloid (17 units +/- 12 units vs. 19 units +/- 11 units, 1 unit +/- 2 units vs. 2 units +/- 3 units, 8 units +/- 8 units vs. 14 units +/- 11 units, 14 L +/- 14 L vs. 9 L +/- 13 L, respectively; p < 0.05). The post-CPG cohort also received a higher ratio transfusion (0.5 +/- 0.31 vs. 0.8 +/- 0.31; p < 0.05) representing a change in practice. Overall mortality was not different between the two groups (24 vs. 19%; p = 0.115). CONCLUSIONS MT patients are now receiving a higher FFP:RBC ratio and less crystalloid after implementation of the CPG. Additionally, patients are now presenting normothermic and have higher hemoglobin levels. All of these changes are consistent with the principles of damage control resuscitation. Changes in practice were associated with implementation of the CPG, maturity of the battlefield, and increased availability of products.

Long range transport of war-related burn casualties

BACKGROUND US military burn casualties are evacuated to the US Army Institute of Surgical Research Burn Center in San Antonio, TX. Patients are transported by US Army Institute of Surgical Research Burn Flight Teams, Air Force Critical Care Air Transport Teams, or routine aeromedical evacuation. This study characterizes the military burn casualties transported by each team and reports associated outcomes. METHODS We performed a retrospective review of burn center registry data, identifying all US burn casualties admitted to the Armys burn center between March 2003 and February 2007. Data included total body surface area (TBSA) burn, ventilatory status, inhalational injury, associated injuries, injury severity, disposition, morbidity, and mortality. RESULTS During 4 years of military operations in Iraq and Afghanistan, 540 casualties were admitted to our burn center for treatment of injuries resulting from war-related operations. Mean burn size was 16.7% total body surface area (range, <1%-95%) with a mean Injury Severity Score of 12.2 +/- 13.7. One hundred eight-one (33.5%) casualties required ventilatory support in flight; inhalation injury was confirmed in 69 (12.7%) patients. Two hundred six (38.1%) were transported by the Burn Flight Team and 174 (32.2%) were transported by Critical Care Air Transport Team, with a mean transit time of 4 days after injury. One hundred sixty (29.6%) patients were routine aeromedical evacuees. There were no in-flight deaths reported; 30 (5.6%) patients died of their wounds at our burn center. CONCLUSIONS Burn casualties represent a group of patients with severe traumatic injuries. Our current system of selectively using specialty medical transport teams for the long-range transport of burn casualties is safe and effective.

Association of Shock, Coagulopathy, and Initial Vital Signs with Massive Transfusion in Combat Casualties

BACKGROUND Timely initiation of a massive transfusion (MT) protocol is associated with improved survival and reduced transfusion for patients requiring MT; however, a priori identification of this population is difficult. The objective of this study was to compare the results of an MT prediction model and actual MT incidence in combat casualties. METHODS We performed a retrospective review of the Joint Theater Trauma Registry transfusion database for all US service personnel injured in combat during overseas contingency operations who received at least 1 unit of blood. Systolic blood pressure at the time of admission, heart rate, hemoglobin, international normalized ratio, and base deficit were used in a previously developed prediction model for MT. RESULTS Casualties (n = 1124) were identified who had received at least 1 unit of blood and had all data points. Of these patients, 420 patients (37%) received an MT. Subjects presenting with any two of four possible variables (heart rate >110, systolic blood pressure <110 mm Hg, base deficit < or = -6, and hemoglobin <11) had a 54% incidence of MT with a model sensitivity of 69%. Patients predicted but not observed to receive an MT had earlier time of death and an increased incidence of head injuries compared with those predicted and observed to receive an MT. Patients not predicted but observed to receive an MT had increased chest, abdominal, and extremity injuries than those neither predicted nor observed to receive an MT. CONCLUSION The decision to implement an MT seems to rely heavily on clinical evaluation of severity of abdominal and extremity injury rather than physiologic derangement. Using a model based on the physiologic parameters--a more objective measure--may decrease mortality in combat casualties.

Continuous Renal Replacement Therapy Improves Survival in Severely Burned Military Casualties with Acute Kidney Injury

BACKGROUND Acute kidney injury in severely burned patients is associated with high mortality. We wondered whether early use of continuous renal replacement therapy (CRRT) changes outcomes in severely burned military casualties with predetermined criteria for acute kidney injury. METHODS Between November 2005 and June 2007, casualties admitted to our burn intensive care unit after sustaining burns in Iraq and Afghanistan, who subsequently developed acute kidney injury or circulatory shock or both, underwent CRRT. Baseline demographic, laboratory, and hemodynamic parameters were recorded. Both 28-day mortality and in- hospital mortality were evaluated and compared with a consecutive group of burn casualties with greater than 40% total body surface area (TBSA) burns, acute kidney injury, or nephrology consultation in the 2 years before the existence of our CRRT program. RESULTS One hundred forty-seven severely burned military casualties were admitted to our intensive care unit before CRRT program initiation, and 102 were admitted after CRRT program initiation. Before the CRRT program, 16 patients were identified as having >40% TBSA burns with kidney injury with or without nephrology consultation (control group); 18 were treated with CRRT since (CRRT group). Groups were similar for %TBSA, %full-thickness TBSA, incidence of inhalation injury, blood urea nitrogen, creatinine, and Injury Severity Score. Of the CRRT patients, seven soldiers were treated for isolated acute kidney injury, whereas 11 were treated for a combination of acute kidney injury and shock. The dose of therapy was 50.2 +/- 13 mL/kg/h with a treatment course of 5.2 +/- 3 days. Of the 11 patients in the CRRT group treated for shock, eight were off vasopressors by 24 hours and the remaining three within 48 hours. None of the patients in the control group were placed on renal replacement therapy with nephrology consultation in eight patients. Both 28-day mortality (22% vs. 75%, p = 0.002) and in-hospital mortality (56% vs. 88%, p = 0.04) were lower in the CRRT group compared with that in the control group. CONCLUSION Aggressive application of CRRT in severely burned casualties with kidney injury significantly improves survival.