Wounding patterns for U.S. Marines and sailors during Operation Iraqi Freedom, major combat phase

Blast-induced neurotrauma: surrogate use, loading mechanisms, and cellular responses

BACKGROUND

With the onset of improved protective equipment against fragmentation, blast-induced neurotrauma has emerged as the "signature wound" of the current conflicts in the Middle East. Current research has focused on this phenomenon; however, the exact mechanism of injury and ways to mitigate the ensuing pathophysiology remain largely unknown. The data presented and literature reviewed formed the fundamentals of a successful grant from the U.S. Office of Naval Research to Wayne State University.

METHODS

This work is a culmination of specialized blast physics and energy-tissue coupling knowledge, recent pilot data using a 12-m shock tube and an instrumented Hybrid III crash test dummy, modeling results from Conventional Weapons effects software, and an exhaustive Medline and government database literature review.

RESULTS

The work supports our hypothesis of the mechanism of injury (described in detail) but sheds light on current hypotheses and how we investigate them. We expose two areas of novel mitigation development. First, there is a need to determine a physiologic and mechanism-based injury tolerance level through a combination of animal testing and biofidelic surrogate development. Once the injury mechanism is defined experimentally and an accurate physiologic threshold for brain injury is established, innovative technologies to protect personnel at risk can be appropriately assessed. Second, activated pathophysiological pathways are thought to be responsible for secondary neurodegeneration. Advanced pharmacological designs will inhibit the key cell signaling pathways. Simultaneously, evaluation of pharmacological candidates will confirm or deny current hypotheses of primary mechanisms of secondary neurodegeneration.

CONCLUSIONS

A physiologic- or biofidelic-based blast-induced tolerance curve may redefine current acceleration-based curves that are only valid to assess tertiary blast injury. Identification of additional pharmaceutical candidates will both confirm or deny current hypotheses on neural pathways of continued injury and help to develop novel prophylactic treatments.

Penetrating missile injuries during the Iraqi insurgency

INTRODUCTION

Since the invasion of Iraq in 2003, the conflict has evolved from asymmetric warfare to a counter-insurgency operation. This study investigates the pattern of wounding and types of injuries seen in casualties of hostile action presenting to a British military field hospital during the present conflict.

PATIENTS AND METHODS

Data were prospectively collected on 100 consecutive patients either injured or killed from hostile action from January 2006 who presented to the sole coalition field hospital in southern Iraq.

RESULTS

Eighty-two casualties presented with penetrating missile injuries from hostile action. Three subsequently died of wounds (3.7%). Forty-six (56.1%) casualties had their initial surgery performed by British military surgeons. Twenty casualties (24.4%) sustained gunshot wounds, 62 (75.6%) suffered injuries from fragmentation weapons. These 82 casualties were injured in 55 incidents (mean, 1.49 casualties; range 1-6 casualties) and sustained a total 236 wounds (mean, 2.88 wounds) affecting a mean 2.4 body regions per patient. Improvised explosive devices were responsible for a mean 2.31 casualties (range, 1-4 casualties) per incident.

CONCLUSIONS

The current insurgency in Iraq illustrates the likely evolution of modern, low-intensity, urban conflict. Improvised explosive devices employed against both military and civilian targets have become a major cause of injury. With the current global threat from terrorist bombings, both military and civilian surgeons should be aware of the spectrum and emergent management of the injuries caused by these weapons.

Blast injuries

Health-care providers are increasingly faced with the possibility of needing to care for people injured in explosions, but can often, however, feel undertrained for the unique aspects of the patient's presentation and management. Although most blast-related injuries (eg, fragmentation injuries from improvised explosive devices and standard military explosives) can be managed in a similar manner to typical penetrating or blunt traumatic injuries, injuries caused by the blast pressure wave itself cannot. The blast pressure wave exerts forces mainly at air-tissue interfaces within the body, and the pulmonary, gastrointestinal, and auditory systems are at greatest risk. Arterial air emboli arising from severe pulmonary injury can cause ischaemic complications-especially in the brain, heart, and intestinal tract. Attributable, in part, to the scene chaos that undoubtedly exists, poor triage and missed diagnosis of blast injuries are substantial concerns because injuries can be subtle or their presentation can be delayed. Management of these injuries can be a challenge, compounded by potentially conflicting treatment goals. This Seminar aims to provide a thorough overview of these unique primary blast injuries and their management.

Battlefield extremity injuries in Operation Iraqi Freedom

OBJECTIVE

Extremity injuries account for the majority of wounds incurred during US armed conflicts. Information regarding the severity and short-term outcomes of patients with extremity wounds, however, is limited. The aim of the present study was to describe patients with battlefield extremity injuries in Operation Iraqi Freedom (OIF) and to compare characteristics of extremity injury patients with other combat wounded.

PATIENTS AND METHODS

Data were obtained from the United States Navy-Marine Corps Combat Trauma Registry (CTR) for patients who received treatment for combat wounds at Navy-Marine Corps facilities in Iraq between September 2004 and February 2005. Battlefield extremity injuries were classified according to type, location, and severity; patient demographic, injury-specific, and short-term outcome data were analysed. Upper and lower extremity injuries were also compared.

RESULTS

A total of 935 combat wounded patients were identified; 665 (71%) sustained extremity injury. Overall, multiple wounding was common (an average of 3 wounds per patient), though more prevalent amongst patients with extremity injury than those with other injury (75% vs. 56%, P<.001). Amongst the 665 extremity injury patients, 261 (39%) sustained injury to the upper extremities, 223 (34%) to the lower extremities, and 181 (27%) to both the upper and lower extremities. Though the total number of patients with upper extremity injury was higher than lower extremity injury, the total number of extremity wounds (n=1654) was evenly distributed amongst the upper and lower extremities (827 and 827 wounds, respectively). Further, lower extremity injuries were more likely than the upper extremity injuries to be coded as serious to fatal (AIS>2, P<.001).

CONCLUSIONS

Extremity injuries continue to account for the majority of combat wounds. Compared with other conflicts, OIF has seen increased prevalence of patients with upper extremity injuries. Wounds to the lower extremities, however, are more serious. Further research on the risks and outcomes associated with extremity injury is necessary to enhance the planning and delivery of combat casualty medical care.

Forward Surgical Teams provide comparable outcomes to combat support hospitals during support and stabilization operations on the battlefield

BACKGROUND

Forward Surgical Teams (FST) provide forward deployed surgical care within the battle space. The next level of care in theater, the Combat Support Hospitals (CSH), are distinguished from the FST by advanced resource capabilities including more complex diagnostic imaging, laboratory support with blood banking, and intensive care units. This study was intended to assess the effect of FST capability on the outcome of seriously injured casualties in comparison to the CSH.

METHODS

We reviewed all casualty records in the Joint Theater Trauma Registry database from April 2004 to April 2006. The study cohort included all US military battle casualties who were admitted to either a FST or a CSH and were not returned to duty within 72 hours. Data were tabulated and assessed for basic demographics, mechanism of injury, injury severity score, ventilator and critical care days, and mortality. Statistical inferences were made using Chi square and Student's t tests.

RESULTS

As of April 2006, the above information was available in the Joint Theater Trauma Registry on 2,617 US military battle casualties who survived to reach care at a FST and/or CSH. Of this population, 77 subsequently died of wounds and 2,540 survived. We found no significant difference in died of wounds rates between the sample populations or rates of ventilator or critical care days between the two groups, nor did controlling for injury severity score alter this picture. The most significant predictor of mortality in both these groups was head injury.

CONCLUSIONS

The disparity between the availability of the highest level of injury care and the ability to care for injury as soon as possible is an issue of central importance to both the civilian and military trauma care communities. Our analysis demonstrates that despite the operational and logistic challenges that burden the FST, this level of surgical care confers equivalent battlefield injury outcome results compared with the CSH.

A review of casualties during the Iraqi insurgency 2006--a British field hospital experience

BACKGROUND

Following the invasion of Iraq in April 2003, British and coalition forces have been conducting counter-insurgency operations in the country. As this conflict has evolved from asymmetric warfare, the mechanism and spectrum of injury sustained through hostile action (HA) was investigated.

METHOD

Data was collected on all casualties of HA who presented to the British Military Field Hospital Shaibah (BMFHS) between January and October 2006. The mechanism of injury, anatomical distribution, ICD-9 diagnosis and initial discharge information was recorded for each patient in a trauma database.

RESULTS

There were 104 HA casualties during the study period. 18 were killed in action (KIA, 21%). Of the remaining 86 surviving casualties, a further three died of their wounds (DOW, 3.5%). The mean number of diagnoses per survivor was 2.70, and the mean number of anatomical regions injured was 2.38. Wounds to the extremities accounted for 67.8% of all injuries, a percentage consistent with battlefield injuries sustained since World War II. Open wounds and fractures were the most common diagnosis (73.8%) amongst survivors of HA. Improvised explosive devices (IEDs) accounted for the most common cause of injury amongst casualties (54%).

CONCLUSIONS

Injuries in conflict produce a pattern of injury that is not seen in routine UK surgical practice. In an era of increasing surgical sub-specialisation, the deployed surgeon needs to acquire and maintain a wide range of skills from a variety of surgical specialties. IEDs have become the modus operandi for terrorists. In the current global security situation, these tactics can be equally employed against civilian targets. Therefore, knowledge and training in the management of these injuries is relevant to both military and civilian surgeons.

Combat casualty care in an air force theater hospital: perspectives of recently deployed cardiothoracic surgeons

Current military operations have generated a large number of casualties and have led to the establishment of the first Air Force Theater Hospital since Vietnam. Located at Balad Airbase, Iraq, this hospital is a busy trauma center. Thoracic injuries are relatively infrequent but highly lethal. The cardiothoracic surgeon is uniquely trained to provide sophisticated surgical management to some of the most severely injured patients. The operative experiences of four recently deployed cardiothoracic surgeons are described. Mortality from combat injury in this conflict is lower than in prior wars. Body armor may prevent some fatal injuries. Several features of military medical care process are helping to improve our outcomes-specifically, the development of a trauma care system modeled on successful civilian centers, the expanded use of damage control concepts, and utilization of early transportation out of the theater of operations using Critical Care Air Transport Teams (CCATT).

Traumatic brain injury during Operation Iraqi Freedom: findings from the United States Navy–Marine Corps Combat Trauma Registry

Object

The purpose of this study was to characterize traumatic brain injuries (TBIs) among military personnel (primarily Marines) during the second phase of Operation Iraqi Freedom from early in the medical care chain of evacuation through Landstuhl Regional Medical Center, a Level 4 American hospital in Germany.

Methods

Data were obtained from the Navy–Marine Corps Combat Trauma Registry (CTR) and included both battle and nonbattle injuries. Follow-up of patients with TBI was conducted to examine the short-term medical and personnel-related effects of TBI among those surviving.

Results

Those injured in battle were more likely than those not injured in battle to have multiple TBI diagnoses, a greater number of all diagnoses, more severe TBIs, and to be medically evacuated. Intracranial injuries (for example, concussions) were the predominant type of TBI, although skull fractures and open head wounds were also seen. Improvised explosive devices were the most common cause of TBIs among battle injuries; blunt trauma and motor vehicle crashes were the most common causes among nonbattle injuries. Short-term follow-up of surviving patients with TBI indicated higher morbidity and medical utilization among the patients with more severe TBI, although mental conditions were higher among patients with milder TBI.

Conclusions

Data from the Navy–Marine Corps CTR provide useful information about combatants' TBIs identified early in the combat casualty process. Results may improve clinical care for those affected and suggest strategies for primary prevention. The CTR staff plans to conduct additional follow-up studies of this group of patients with TBI.

Epidemiology of infections associated with combat-related injuries in Iraq and Afghanistan

Enhanced medical training of front line medical personnel, personal protective equipment, and the presence of far forward surgical assets have improved the survival of casualties in the current wars in Iraq and Afghanistan. As such, casualties are at higher risk of infectious complications of their injuries including sepsis, which was a noted killer of casualties in previous wars. During the current conflicts, military personnel who develop combat-related injuries are at substantial risk of developing infections with multidrug resistant bacteria. Herein, we describe the bacteriology of combat-related injuries in Operation Iraqi Freedom and Operation Enduring Freedom that develop infections with particular attention to injuries of the extremities, central nervous system, abdomen and thorax, head and neck, and burns. In addition, the likely sources of combat-related injuries with multidrug resistant bacteria infections are explored.

Guidelines for the prevention of infection after combat-related injuries

Management of combat-related trauma is derived from skills and data collected in past conflicts and civilian trauma, and from information and experience obtained during ongoing conflicts. The best methods to prevent infections associated with injuries observed in military combat are not fully established. Current methods to prevent infections in these types of injuries are derived primarily from controlled trials of elective surgery and civilian trauma as well as retrospective studies of civilian and military trauma interventions. The following guidelines integrate available evidence and expert opinion, from within and outside of the US military medical community, to provide guidance to US military health care providers (deployed and in permanent medical treatment facilities) in the diagnosis, treatment, and prevention of infections in those individuals wounded in combat. These guidelines may be applicable to noncombat traumatic injuries under certain circumstances. Early wound cleansing and surgical debridement, antibiotics, bony stabilization, and maintenance of infection control measures are the essential components to diminish or prevent these infections. Future research should be directed at ideal treatment strategies for prevention of combat-related injury infections, including investigation of unique infection control techniques, more rapid diagnostic strategies for infection, and better defining the role of antimicrobial agents, including the appropriate spectrum of activity and duration.

Head, face, and neck injuries during Operation Iraqi Freedom II: results from the US Navy-Marine Corps Combat Trauma Registry

BACKGROUND

Head, face, and neck injuries (HFNIs) are an important source of combat mortality and morbidity. The objective of this study was to document the characteristics and causes of HFNIs during Operation Iraqi Freedom II.

METHODS

A retrospective review of HFNIs sustained by US military casualties between March 1, 2004 and September 30, 2004 was performed. Data were collected from the Navy-Marine Corps Combat Trauma Registry.

RESULTS

During the study period, 39% of all injury casualties in the registry had HFNIs. Of the 445 HFNI patients, one-third presented with multiple wounds to the head, face, and neck. Four percent of battle HFNI patients died from wounds, and nearly 40% of the surviving wounded were evacuated for treatment. Improvised explosive devices (IEDs) were the most frequent cause of battle HFNIs. Nonbattle HFNIs were most often the result of motor vehicle crashes. The majority (65%) of all HFNIs were to the face. Head injuries, overall, were more severe than face or neck wounds according to the Abbreviated Injury Scale.

CONCLUSIONS

The proportion of combat-related HFNIs is increasing and is primarily caused by IEDs. Improved protection for the vulnerable facial region is needed. Continued research on the changing nature of warfare and distribution of HFNIs is necessary to enhance the planning and delivery of combat casualty medical care.

The utility of focused assessment with sonography for trauma as a triage tool in multiple-casualty incidents during the second Lebanon war

OBJECTIVE

The purpose of this study was to evaluate the role of focused assessment with sonography for trauma (FAST) as a triage tool in multiple-casualty incidents (MCIs) for a single international conflict.

METHODS

The charts of 849 casualties that arrived at our level 1 trauma referral center were reviewed. Casualties were initially triaged according to the Injury Severity Score at the emergency department gate. Two-hundred eighty-one physically injured patients, 215 soldiers (76.5%) and 66 civilians (23.5%), were admitted. Focused assessment with sonography for trauma was performed in 102 casualties suspected to have an abdominal injury. Sixty-eight underwent computed tomography (CT); 12 underwent laparotomy; and 28 were kept under clinical observation alone. We compared FAST results against CT, laparotomy, and clinical observation records.

RESULTS

Focused assessment with sonography for trauma results were positive in 17 casualties and negative in 85. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of FAST were 75%, 97.6%, 88.2%, 94.1%, and 93.1%, respectively. A strong correlation between FAST and CT results, laparotomy, and clinical observation was obtained (P < .05).

CONCLUSIONS

In a setting of a war conflict-related MCI, FAST enabled immediate triage of casualties to laparotomy, CT, or clinical observation. Because of its moderate sensitivity, a negative FAST result with strong clinical suspicion demands further evaluation, especially in an MCI.

Characterization of extremity wounds in Operation Iraqi Freedom and Operation Enduring Freedom

OBJECTIVES

Extremity wounds and fractures traditionally comprise the majority of traumatic injuries in US armed conflicts. Little has been published regarding the extremity wounding patterns and fracture distribution in the current conflicts in Iraq and Afghanistan. The intent of this study was to describe the distribution of extremity fractures during this current conflict.

DESIGN

Descriptive epidemiologic study.

METHODS

The Joint Theater Trauma Registry was queried for all US service members receiving treatment for wounds (ICD-9 codes 800-960) sustained in Operation Iraqi Freedom (OIF) and Operation Enduring Freedom (OEF) from October 2001 through January 2005. Returned-to-duty and nonbattle injuries were excluded. Wounds were classified according to region and type. Extremity wounds were analyzed in detail and compared to published results from previous conflicts.

RESULTS

A total of 1281 soldiers sustained 3575 extremity combat wounds. Fifty-three percent of these were penetrating soft-tissue wounds and 26% were fractures. Of the 915 fractures, 758 (82%) were open fractures. The 915 fractures were evenly distributed between the upper (461, 50%) and lower extremities (454, 50%). The most common fracture in the upper extremity was in the hand (36%) and in the lower extremity was the tibia and fibula (48%). Explosive munitions accounted for 75% of the mechanisms of injury.

CONCLUSIONS

The burden of wounds sustained in OIF/OEF is extremity injuries, specifically soft-tissue wounds and fractures. These results are similar to the reported casualties from previous wars.