Short-Term Outcomes and Complications of Damage Control and Definitive Laparotomy in Deployed Combat Environments: 2002 to 2011

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1 MILITARY MEDICINE, 181, 3:277, 2016 Short-Term Outcomes and Complications of Damage Control and Definitive Laparotomy in Deployed Combat Environments: 2002 to 2011 CPT Thomas A. Mitchell, MC USA*; MAJ Cynthia L. Lauer, MC USA*; James K. Aden, PhD ; LTC Kurt D. Edwards, MC USA*; Col Jeffrey A. Bailey, USAF MC ; LTC Christopher E. White, MC USA*; COL Lorne H. Blackbourne, MC USA*; COL John B. Holcomb, MC USA (Ret.) ABSTRACT Introduction: Damage control laparotomy (DCL) in an austere environment is an evolving surgical modality. Methods: A retrospective evaluation of all patients surviving 24 hours who underwent a laparotomy from 2002 to 2011 in Iraq and Afghanistan was performed. DCL was defined as a patient undergoing laparotomy at two distinct North American Treaty Organization (NATO) Role 2 or 3 medical treatment facilities (MTFs); a NATO Roles 2 and 3 MTFs, and/or having the International Classification of Diseases, 9th Revision, Clinical Modification procedure code 54.12, for reopening of recent laparotomy site. Definitive laparotomy (DL) was defined as patients undergoing one operative procedure at one NATO Role 2 or 3 MTF. Demographic data including injury severity scores, hematological transfusion, mortality, intraperitoneal or retroperitoneal operative interventions, and complications were compared. Results: DCL composed of 26.5% (n = 331) of all 1,248 laparotomies performed between March 2002 and September Total intra-abdominal, acute respiratory distress syndrome, and thromboembolic complications for DCL versus DL were 8.5% and 5.6% ( p = 0.07), 2.1% and 0.8% ( p = 0.06), and 1.5% and 0.7% ( p = 0.17), respectively. Theater discharge mortality from DCL and DL were 1.5% (n =5),and1.4%(n = 13) ( p = 0.90), respectively. Conclusions: In conclusion, excluding deaths with the first 24 hours, DCL and DL had comparable mortality and complication rates at NATO Roles 2 and 3 MTFs. *Department of General Surgery, San Antonio Military Medical Center, 3551 Roger Brooke Drive, JBSA Fort Sam Houston, TX United States Army Institute of Surgical Research, 3698 Chambers Pass STE B, JBSA Fort Sam Houston, TX Division of Acute Care Surgery, Department of Surgery, University of Texas Health Sciences Center at Houston, 7000 Fannin Street, Houston, TX This article was an oral podium presentation at the 2014 American Association for the Surgery of Trauma Conference, Philadelphia, PA, September 12, doi: /MILMED-D INTRODUCTION Damage control laparotomy (DCL) is an integral component of the U.S. military s December 2004 implementation of the Damage control resuscitation Clinical Practice Guideline that revolutionized care for service members in an austere environment. 1 The inception of damage control surgery emerged initially from the civilian Dr. Harlan Stone in 1983, and the term damage control (DC) was codified in 1993 by Rotondo et al. 2 Interestingly, damage control derives from a Navy term referring to keeping a badly damaged ship afloat after a major penetrating injury to the hull. 3 Conceptually, DC includes three distinct phases. First, DCL is implemented to control hemorrhage and intraperitoneal contamination with subsequent utilization of a temporary abdominal closure. Second, judicious fluid resuscitation with aggressive correction of coagulopathy, acidosis, and hypothermia begins in the prehospital/preoperative environments and culminates in the intensive care unit. Third, definitive repair of all traumatic injuries is performed after correction of physiological derangements. DCL is associated with improved outcomes and decreased mortality in severely injured civilian trauma patients. 4 6 One of the first DCL procedures in a military environment was performed in 1993 in Somalia. 7 Before the conflicts in Afghanistan, Operations Enduring Freedom (OEF), and Iraq, Operation Iraqi Freedom (OIF) and Operation New Dawn (OND), the military s ability to implement DCL was cautioned by Eiseman et al 3 in 2000 Archives of Surgery stating that DCS will be impractical for common use in a forward military unit during times of war secondary to enormous logistic commitments. However, these military conflicts have enabled the U.S. military to implement a military medical revolution entitled global combat damage-control surgery involving multiple geographically distinct surgical facilities, multiple surgeons, multiple resuscitations, and aeromedical evacuation to U.S. military health care facilities encompassing up to 10 discrete phases. Currently, four published articles in the medical literature describe American and British experiences with DC surgery in Iraq and Afghanistan However, a larger and more comprehensive retrospective analysis on all U.S. service members undergoing laparotomy from Iraq and Afghanistan has not been performed. We sought to identify the overall number of U.S. service members undergoing DCL versus definitive laparotomy (DL) from 2002 to Second, we sought to identify if there was a difference in DCL implementation in Iraq compared to Afghanistan. We hypothesized that no difference would exist MILITARY MEDICINE, Vol. 181, March

2 in the overall rate of DCL implementation irrespective of geographic location. Third, we sought to identify the prevalence of short-term complications of patients undergoing DCL and DL in Iraq and Afghanistan. We hypothesized that patients undergoing DCL would have a higher complication rate than patients undergoing DL within the first 24 to 48 hours of the initial procedure. Fourth, we sought to characterize the intraoperative differences between DL and DCL by enumerating which anatomical organs were injured in both populations. We hypothesized that patients undergoing DCL would have more anatomical organs injured compared to patients undergoing DL. Fifth, we sought to identify whether mortality difference in Iraq and Afghanistan existed between patients undergoing DCL and DL. We hypothesized that patients surviving a minimum of 24 hours undergoing both DL and DCL would have no early mortality differences. METHODS This is a retrospective analysis of U.S. military personnel wounded in Afghanistan, OEF, and Iraq, OIF and OND, from March 2002 to September In this study, all service members serving in Iraq included campaigns OND, September 2010 to September 2011, and OIF, March 2002 to August 2010, for final data analysis. 12 This information was obtained from the Department of Defense Trauma Registry (DoDTR) and Patient Administration Systems and Biostatistics Activity (PASBA). PASBA is the Army Medical Department s executing agency for the Military Health System Data Quality Management Control Program that aims to enhance clinical outcomes. 13 The DoDTR collects battle and nonbattle injury demographics, care, and outcomes for patients admitted to theater North American Treaty Organization (NATO) Roles 2 and 3 facilities with an International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9) injury diagnosis and includes outcomes through discharge from acute hospitalization. 14 These two sources were queried for all U.S. military service members who underwent laparotomy in Iraq and Afghanistan at NATO Role 2 or 3 medical treatment facilities (MTFs) who survived a minimum of 24 hours. Data analysis from MTFs present in Landstuhl, Germany, Outside the Contiguous United States (OCONUS), and Contiguous United States (CONUS) such as San Antonio Military Medical Center were not available and were excluded to capture demographics, outcomes, and complications related specifically to deployed theater environments. NATO Role 2 MTFs are resourced to provide DC surgical capabilities including up to two operating tables, 20 personnel including up to 3 general surgeons and 1 orthopedic surgeon, can offer postsurgical intensive monitoring for up to 8 patients for 6 hours. 15 NATO Role 3 MTFs such as Army Combat Support Hospitals are the highest level of trauma care in theater with capabilities approaching a civilian American College of Surgeons verified level 2 trauma center including capacity for up to 248-bed hospital with six operating rooms. Data analysis yielded subject demographic data, laboratory data, vital signs, overall blood product utilization, and discharge status (dead or alive) at NATO Role 3 MTF discharge The severity of injury was compared using abdominal abbreviated injury scores (AIS) and injury severity scores (ISS). The geographic location of the documented ICD-9 operative codes and the specific ICD-9 operative codes were utilized to differentiate between patients undergoing DCL and DL. DCL was defined as a patient undergoing laparotomy at two distinct NATO Role 2 or 3 MTFs; a NATO Role 2 and 3 MTFs, and/or having the ICD-9 procedure code 54.12, for reopening of recent laparotomy site. DL was defined as patients undergoing one operative procedure at one NATO Role 2 or 3 MTF. Patients without identification of an intraperitoneal or retroperitoneal operative procedure at a defined geographic location were excluded from data analysis. Furthermore, the ICD-9 intraoperative procedure codes on intraperitoneal and retroperitoneal organ systems (i.e., spleen, colon, and diaphragm) were characterized for each patient undergoing DL and DCL to attempt to calculate an overall organ injury burden sustained. Finally, ICD-9 complication codes were utilized to calculate the total number of intra-abdominal, acute respiratory distress syndrome (ARDS), and thromboembolic complications. Intra-abdominal complications were defined by ICD-9 complication codes 22 (abdominal compartment syndrome), 25 and 30 (dehiscence/evisceration), 40 (ileus), 41 (intra-abdominal abscess), 53 (postoperative hemorrhage), 63 (soft tissue infection), and 66 (wound infection). ARDS ICD-9 complication code was no. 4. Thromboembolic complications were defined by ICD-9 complication code numbers 56 (pulmonary embolus), and 24 (deep venous thrombosis). These data were collated on a Microsoft Excel (Microsoft, Redmond, Washington) spreadsheet and SAS software (Cary, North Carolina) was utilized to perform all statistical analysis. Categorical data were analyzed using a χ 2 test. Mantel Haenszel test or Fischer s exact data analysis was performed by juxtaposing DL versus DCL demographic information to evaluate for significance. All continuous data are presented as medians with interquartile ranges (IQR), and t test or Wilcoxon s test was used for statistical comparisons. A p value of less than 0.05 was considered to be statistically significant. RESULTS 1,248 patients meet the inclusion criteria between March 2002 and September 2011, and their demographic information is included in Table I. 26.5% (n = 331) underwent DCL. Of all laparotomies initiated at NATO Role 2, 54.1% (n = 151) resulted in DCL, compared to 18.6% (n = 180) of laparotomies initiated at NATO Role 3 MTFs ( p < 0.01). DCL composed 19.5% (n = 154) and 38.7% (n = 177) of all laparotomies in Iraq and Afghanistan, respectively ( p < 0.01). The mechanism of injury for patients undergoing 278 MILITARY MEDICINE, Vol. 181, March 2016

3 TABLE I. Demographic Information: DCL Versus DL Variable DCL (n = 331) DL (n = 917) p Value (MHCS or Satterthwaite) Final Theater discharge (Dead) 1.5% (n = 5) 1.4% (n = 13) 0.90 Gender (Male) 99.4% (n = 329) 97.9% (n = 898) 0.08 Theater of Operation Afghanistan 53.5% (n = 177) 30.5% (n = 280) <0.01 Iraq 46.5% (n = 154) 69.5% (n = 637) NATO MTF (Location[s] of Laparotomy) Role 2 0.0% (n = 0) 14.0% (n = 128) <0.01 Role 2 to 2 0.3% (n = 1) 0.0% (n =0) Role 2 to % (n = 150) 0.0% (n =0) Role % (n = 49) 86.0% (n = 789) Role 3 to % (n = 131) 0.0% (n =0) Mechanism of Injury Blunt 19.9% (n = 66) 44.6% (n = 409) <0.01 Burn 0.9% (n = 3) 1.2% (n = 11) Penetrating 79.2% (n = 262) 54.2% (n = 497) Dominant Injury Cause Bullet/GSW/Firearm 35.6% (n = 118) 21.5% (n = 197) Fischer s Exact Test < 0.01 Explosive Device 60.7% (n = 201) 67.3% (n = 617) MVC 1.5% (n = 5) 5.3% (n = 49) Age 24 (21, 27) 24 (21, 29) 0.13 ISS 29 (19, 36) 22 (14, 30) <0.01 AIS Head 0 (0, 2) 0 (0,1) 0.76 Face 0 (0, 1) 0 (0, 1) 1.00 Chest 0 (0, 3) 0 (0, 3) 0.09 Abdomen 3 (2, 4) ; 3.3 ± (2, 4); 2.6 ± 1.4 <0.01 Extremity/Pelvis 3 (0, 4) 2 (0, 3) <0.01 Skin 1 (1, 1) 1 (1, 1) 0.56 Min ED Glasgow Coma Scale (Total) 3 (3, 11) 15 (3, 15) <0.01 Packed Red Blood Cells (Total) 7 (2, 19) 4 (0, 10) <0.01 Plasma (Total) 6 (2, 14) 3 (0, 9) <0.01 Data presented as median (IQR 1, IQR 3). Data presented as mean ± standard deviation. Patients undergoing DCL compared to DL had a higher ISS, abdominal AIS, extremity/pelvic AIS, required more prbcs/ffp, and had a similar short-term mortality. Although the median demonstrates no difference between abdominal AIS in DL and DCL, the mean is utilized to demonstrate the difference in the two populations. DCL compared to DL was more likely to be a penetrating injury (79.2% [n = 262] versus 54.2% [n = 497], p < 0.01). Patients undergoing DCL compared to DL had a higher ISS (29 [19, 36] versus 22 [14, 30], p < 0.01), required more prbc (7 [2, 19] versus 4 [0, 10], p < 0.01) and FFP (6 [2, 14] versus 3 [0, 9], p < 0.01). After excluding those who died within 24 hours, the residual mortality in the second 24 hours was the same, (1.5% [n = 5] versus 1.4 % [n = 13], p = 0.9). Physiological and laboratory data are presented in Table II with the most notable clinically significant difference is an increased maximal emergency department (ED) heart rate in patients undergoing DCL compared to DL, (120 [102, 136] versus 102 [86, 121], p < 0.01). No significant trends in DCL utilization were used in Afghanistan ( p = 0.09) or Iraq ( p = 0.68) were identified from 2002 to Table III indicates the overall intraperitoneal and retroperitoneal organs injured for both DCL and DL patient populations; notably, vascular and colonic organ surgical interventions predicted DCL over DL whereas a splenic organ intervention did not demonstrate a difference. Figure 1 demonstrates the direct correlation between the number of intraperitoneal and retroperitoneal organs injured and their propensity to undergo DCL. DCL patients had more intraperitoneal or-retroperitoneal organs requiring operative intervention, 1.8 ± 1.4 versus 0.9 ± 1.0 ( p < 0.05). Table IV demonstrates the short-term complications at NATO Role 2 and 3 MTFs with the only noted short-term difference TABLE II. Physiologic and Laboratory Data for DCL and DL Variable DCL (n = 331) DL (n = 917) p Value Maximum ED 120 (102, 136) 102 (86, 121) <0.01 Pulse Rate Minimum ED SBP 109 (97, 124) 119 (100, 134) <0.01 Minimum ED 7.31 (7.24, 7.38) 7.34 (7.28, 7.39) 0.28 BG ph Minimum ED 3 ( 7, 0) 2 ( 6, 1) <0.01 Base Deficit Minimum ED INR 1.2 (1.0, 1.4) 1.2 (1.0, 1.4) 0.46 Minimum ED Hct 34 (30.1, 38.2) 36.3 (31.0, 41.7) <0.01 SBP, systolic blood pressure; BG, blood gas; INR, international normalized ratio; Hct, hematocrit. Patients undergoing DCL had a clinically significant higher maximal heart rate compared to patients undergoing DL. MILITARY MEDICINE, Vol. 181, March

4 TABLE III. Anatomical Organs Requiring Operating Intervention: DCL Versus DL Operative Injury DCL (n = 331) DL (n = 917) p Value Stomach 7.0% (n = 23) 2.7% (n = 25) <0.01 Small bowel 29.0% (n = 96) 17.3% (n = 159) <0.01 Colon 50.2% (n = 166) 24.1% (n=221) <0.01 Rectum 6.7% (n = 22) 0.9% (n = 8) <0.01 Spleen 20.0% (n = 66) 19.4% (n = 178) 0.84 Liver 7.3% (n = 24) 3.7% (n = 34) <0.01 Diaphragm 10.9% (n = 36) 5.7% (n = 52) <0.01 Pancreas 3.9% (n = 13) 1.3% (n = 12) <0.01 Genitourinary 18.1% (n = 60) 10.3% (n = 94) <0.01 Vascular 17.2% (n = 57) 4.8% (n = 44) <0.01 Appendix 1.8% (n = 6) 1.4% (n = 13) 0.62 Peritoneum 1.2% (n = 4) 0.9% (n = 8) 0.59 Mesentery 1.2% (n = 4) 1.1% (n = 10) 0.86 Gall Bladder 3.0% (n = 10) 0.6% (n = 5) <0.01 Omentum 0% (n = 0) 0.2% (n = 2) 0.40 Esophagus 0.6% (n = 2) 0.2% (n = 2) 0.29 Vascular and Colonic interventions predicted utilization of DCL; however, splenic intervention did not demonstrate a difference between DCL and DL. FIGURE 1. Number of anatomical organs requiring operative intervention and percentage of DCL implemented. TABLE IV. in dehiscence/evisceration and wound/soft tissue infections present within the DCL patient group. DISCUSSION 26.5% (n = 331) of all laparotomies in patients surviving greater than 24 hours in Iraq and Afghanistan between 2002 and 2011 were considered to meet inclusion criteria for DCL. DCL was more frequently performed in Afghanistan and for penetrating injury mechanisms. Higher abdominal and extremity AIS correlated with increased utilization of DCL. DCL correlated with the increased number of organ systems requiring operative intervention. Importantly, despite higher abdominal AIS, ISS, and larger hematological resuscitations, patients undergoing DCL and DL had similar short-term complication rates and mortality for patients who survived greater than 24 hours. Combat DCL as an integral component of combat damage control surgery (CDCS) is a multifaceted, multidisciplinary, and intercontinental logistical medical coordination as defined in Emergency War Surgery, 4th edition with attempts at restoring normal physiology rather than normal anatomy. Specifically, deployed military surgeons have been prompted to utilize damage control techniques when there are multiple life-threatening injuries, acidosis (ph < 7.25), hypothermia (temperature < 34 C), shock on presentation, combined hollow viscus and vascularized organ injury or vascular injury, coagulopathy (INR > 1.4) or a mass casualty situation. 16 Blackbourne describes that CDCS may include up to 10 discrete steps encompassing battlefield evacuation, surgical operations, and resuscitations. Although the implementation of this revolutionary concept has been applied since the outset of the military conflicts in Afghanistan and Iraq, only two American published articles document our recent military use of DCL. We have demonstrated in this study that 26.5% (n =331) of all laparotomies with service members surviving greater than 24 hours underwent DCL. Comparable to U.S. civilian literature on damage control surgery, U.S. service members undergoing DCL had higher ISS, (29 [IQR 19.0, 36] Short-Term NATO Roles 2 and 3 Complications From DCL and DL DCL (n = 331) DL (n = 917) p Value Total Intra-Abdominal 28 (8.5%) 51 (5.6%) 0.07 ACS 10 (3.0%) 34 (3.7%) 0.73 Dehiscence/Evisceration 4 (1.2%) 0 (0.0%) <0.01 Ileus 3 (0.9%) 6 (0.7%) 0.71 Intra-Abdominal Abscess 1 (0.3%) 0 (0.0%) 0.27 Postoperative Hemorrhage 5 (1.5%) 8 (0.9%) 0.35 Wound and Soft Tissue Infections 5 (1.5%) 3 (0.3%) 0.03 ARDS 7 (2.1%) 7 (0.8%) 0.06 Thromboembolic Complications (Deep Venous Thrombosis/Pulmonary Embolus) 5 (1.5%) 6 (0.7%) 0.17 The main short-term differences between DCL and DL existed with dehiscence/evisceration and wound/soft tissue infections; however, the remainder of the short-term complications did not demonstrate a difference between the two surgical modalities. 280 MILITARY MEDICINE, Vol. 181, March 2016

5 versus 22 [14, 30], p < 0.01), higher abdominal AIS, (3 [2, 4] versus 3 [2, 4], p < 0.01), lower ED Glasgow Coma Scale, (3 [3, 11] versus 15 [3, 15], p < 0.01), higher maximum ED pulse rate, (120 [102, 136] versus 102 [86, 121], p < 0.01), higher minimum base deficit, ( 3 [ 7, 0] versus 2 [ 6, 1], p < 0.01) and higher total packed red blood cell, (7 [2, 19] versus 4 [0, 10], p < 0.01), and total plasma, (6 [2, 14] versus 3 [0, 9], p < 0.01) resuscitations. Expectedly, patients requiring more intraperitoneal and retroperitoneal organ interventions were more likely to have DCL performed. Importantly, service members undergoing DCL compared to DL who survived a minimum of 24 hours had no difference in mortality, total intra-abdominal, ARDS, and thromboembolic complications in the first 72 to 96 hours after injury within the austere environments of Iraq and Afghanistan before aeromedical evacuation to Landstuhl, Germany and subsequently to definitive treatment in the United States. However, further investigation needs to evaluate the specific complications such as soft tissue infections and dehiscence/ evisceration complications in patients undergoing DCL. The high prevalence of injuries from explosive devices encompassed 65.5% (n = 818) of all service members injury mechanisms is unparalleled in the civilian literature. Furthermore, the high prevalence of explosive device injuries correlates with service members with more severely injured extremities. Therefore, the increased extremity/pelvic injuries of DCL versus DL, (3 [0, 4] versus 2 [0, 3], p < 0.01) may correlate with an increased propensity to perform DCL after obtaining proximal vascular control to perform a second look operation. Second, in addition to the traditional markers of injury (e.g., ISS, penetrating injury mechanism, high abdominal extremity score), initiation of a laparotomy at NATO Role 2 MTF compared to a Role 3 MTF was associated with DCL versus DL, (54.1% [n = 151] versus 18.6% [n = 180], p < 0.01). CDCS at smaller NATO Role 2 MTFs enables deployed general surgeons the opportunity to quickly stabilize the wounded service member before aeromedical evacuation to a more robust NATO Role 3 MTF with more capabilities to perform definitive operations. Tactically, DCL is an excellent maneuver to rapidly assess and stabilize intraperitoneal and retroperitoneal injuries sustained by service members quickly during periods of high throughput, during mass casualties, and/or prolonged medical evacuations. The identical and low mortality of nearly 1.5% apiece between the DCL and DL patient populations is related to the conception of this study. This protocol excluded patients who died within 24 hours postinjury, and most of the patients eligible for DCL would have been excluded. Furthermore, this protocol only evaluated patients while in theater at NATO Role 2 or 3 MTFs; we did not have outcomes available for casualties evacuated to Germany or the United States, therefore, this data set only represents several days of inpatient care while in an austere environment, and does not thoroughly take into account long-term complications such as sepsis, multiorgan failure, thromboembolic consequences, or death from traumatic brain injury. Median time to hemorrhagic death is 2.6 hours. Most deaths after these types of injuries occur within 24 hours (hemorrhage) and after 72 hours secondarily from traumatic brain injury and multiorgan failure. 16 Future comprehensive research needs to be aimed at evaluating outcomes at NATO 1 to 5 MTFs for patients undergoing DCL and DL for all injured patients in an austere environment. This retrospective analysis is limited by the accurate ICD-9 documentation in an austere environment, and appropriate extraction from the DoDTR military medical databases. Medical charts were unavailable for review of the 1,248 patients to internally verify extracted data. Furthermore, the inability to perform a medical chart review precludes the identification of DCL at a single NATO Role 2 or 3 MTF, as all of the operative procedures were assumed to originate from one planned operation; however, this may have encompassed multiple take backs documented without the ICD-9 code: 54.12, for reopening of recent laparotomy site; therefore, this limitation may underestimate the true utilization of DCL in an austere environment. Service members who may have undergone a DL at a NATO Role 2 or 3 MTF may have had to be unexpectedly reopened at a latter facility, which would have utilized the same ICD-9 code: 54.12, and this may have overestimated the true number of service members undergoing DCL. This data set didn t include data from OCONUS or CONUS MTFs, as many of the patients documented to have a DL at a NATO Role 3 MTF may have been transferred to OCONUS with a temporary abdominal closure, but this information would not have been captured within our data extraction, thus underestimating the number of patients undergoing DCL. Finally, the exclusion of service members who died within 24 hours may likely underestimate the utilization of DCL, as these severely injured service members who are dying within the first 24 hours, are themostlikelyonestoundergodcl. 17 Finally, lack of outcome data after the first 48 to 72 hours severely limits any comment about outcomes, as the inflammatory complications of the survivors will occur in the excluded phase. CONCLUSIONS Although this retrospective evaluation of DCL in combat environments from 2002 to 2011 is limited, the true implementation of DCL in an austere environment is likely higher than 26.5% (n = 331), and the in-theater, Afghanistan and Iraq, mortality and complication rates for DL and DCL for the first 72 to 96 hours after injury in patients surviving greater than 24 hours demonstrated no difference. Future retrospective analysis incorporating all OCONUS and CONUS service member operative procedures, outcomes, and shortterm complications for all service members injured in Iraq and Afghanistan will be critical to evaluating the implementation of DCL as a component of global CDCR that will be an integral component of future military medical campaigns. MILITARY MEDICINE, Vol. 181, March

6 ACKNOWLEDGMENTS The authors acknowledge the Department of Defense Trauma Registry (DoDTR) and the Patient Administration Systems and Biostatistics Activity (PASBA) for providing data for this study. The authors would like to disclose that no external funds were used to finance this project, and the U.S. Military was solely responsible for funding this research. REFERENCES 1. Joint Theater Trauma System Clinical Practice Guideline. Damage Control Resuscitation at Level 2b/3 Treatment Facilities, February 11, Available at 20Control%20Resuscitation%20-%201%20Feb% pdf; accessed December 15, Godat L, Kobayashi L, Costantini T, Coimbra R: Abdominal damage control surgery and reconstruction: world society of emergency surgery position paper. World J Emerg Surg 2013; 8(1): Eiseman B, Moore EE, Meldrum DR, Raeburn C: Feasibility of damage control surgery in the management of military combat casualties. Arch 2000; 135(11): Duchesne JC, Kimonis K, Marr AB, et al: Damage control resuscitation in combination with damage control laparotomy: a survival advantage. J Trauma 2010; 69(1): Blackbourne LH, Baer DG, Eastridge BJ, et al: Military medical revolution: deployed hospital and en route care. J Trauma Acute Care Surg 2012; 73(6): S Blackbourne LH: Combat damage control surgery. Crit Care Med 2008; 36(Suppl 7): S Mabry RL, Holcomb JB, Baker AM, et al: United States Army Rangers in Somalia: an analysis of combat casualties on an urban battlefield. J Trauma 2000; 49(3): , discussion Smith IM, Beech ZK, Lundy JB, Bowley DM: A prospective observational study of abdominal injury management in contemporary military operations: damage control laparotomy is associated with high survivability and low rates of fecal diversion. Ann Surg 2015; 261(4): Bograd B, Rodriguez C, Amdur R, Gage F, Elster E, Dunne J: Use of damage control and the open abdomen in combat. Am Surg 2013; 79(8): Arthurs Z, Kjorstad R, Mullenix P, Rush RM Jr, Sebesta J, Beekley A: The use of damage-control principles for penetrating pelvic battlefield trauma. Am J Surg 2006; 191(5): Fries CA, Penn-Barwell J, Tai NR, Hodgetts TJ, Midwinter MJ, Bowley DM: Management of intestinal injury in deployed UK hospitals. J R Army Med Corps 2011; 157(4): CNN World News: Operation Iraqi Freedom and Operation New Dawn Fast Facts. Available at operation-iraqi-freedom-and-operation-new-dawn-fast-facts/; accessed June 6, United States Army Medical Department: Patient administration systems and biostatistics activity, Available at accessed May 4, Medical Communications for Combat Casualty Care: Joint theater trauma registry, Available at accessed May 4, Department of Defense: United States of America. Emergency war surgery: fourth United States revision. Borden Institute, Available at 5b33-4b3f-968c-2cd95f7b7809; accessed April 21, Holcomb JB, del Junco DJ, Fox EE, et al: The prospective, observational, multicenter, major trauma transfusion (PROMMTT) study: comparative effectiveness of a time-varying treatment with competing risks. JAMA Surg 2013; 148(2): Barbosa RR, Rowell SE, Fox EE, et al: Increasing time to operation is associated with decreased survival in patients with a positive FAST examination requiring emergent laparotomy. J Trauma Acute Care Surg 2013; 75(1): S MILITARY MEDICINE, Vol. 181, March 2016