A 20-year retrospective analysis of deep venous thrombosis and pulmonary embolism among combat casualties requiring damage control laparotomy at US Military Role 2 surgical units.

BACKGROUND: Combat casualties receiving damage control laparotomy at forward deployed, resource-constrained US Military Role 2 surgical units (R2) require multiple evacuations, but the added risk of venous thromboembolism (VTE) in this population has not been defined. To fill this gap, we retrospectively analyzed 20 years of Department of Defense Trauma Registry (DoDTR) data to define the VTE rate in this population. METHODS: DoDTR from 2002 to 2023 was queried for US Military combat casualties requiring damage control laparotomy at R2. All deaths were excluded in subsequent analysis. Rates of VTE were assessed, and subgroup analysis was performed on patients requiring massive transfusion. RESULTS: DoDTR (n = 288) patients were young (mean age 25 years), predominantly male (98%) with severe (mean ISS 26), mostly penetrating injury (76%), and high mortality. VTE rate was high: 15.8% (DVT: 10.3% and PE 7.1%). In the massively transfused population, the VTE rate was even higher (26.7% vs 10.2%, p < 0.001). CONCLUSIONS: This is the first report that combat casualties requiring damage control laparotomy at R2 have such high VTE rates. Therefore, for military casualties, we propose screening ultrasound upon arrival to each subsequent capable echelon of care and low threshold for initiating thromboprophylaxis. LEVEL OF EVIDENCE: Prognostic and Epidemiological, Level IV.

Advanced Surgical Skills for Exposure in Trauma (ASSET) course improves military surgeon confidence.

OBJECTIVE: Active duty military surgeons often have limited trauma surgery experience prior to deployment. Consequently, military-civilian training programs have been developed at high-volume trauma centers to evaluate and maintain proficiencies. Advanced Surgical Skills for Exposure in Trauma (ASSET) was incorporated into the predeployment curriculum at the Army Trauma Training Detachment in 2011. This is the first study to assess whether military surgeons demonstrated improved knowledge and increased confidence after taking ASSET. DESIGN: Retrospective cohort study. SETTING: Quaternary care hospital. PATIENTS AND PARTICIPANTS: Attending military surgeons who completed ASSET between July 2011 and October 2020. MAIN OUTCOME MEASURE(S): Pre- and post-course self-reported comfort level with procedures was converted from a five-point Likert scale to a percentage and compared using paired t-tests. RESULTS: In 188 military surgeons, the median time in practice was 3 (1-8) years, with specialties in general surgery (52 percent), orthopedic surgery (29 percent), trauma (7 percent), and other disciplines (12 percent). The completed self-evaluation response rate was 80 percent (n = 151). The self-reported comfort level for all body regions improved following course completion (p < 0.001): chest (27 percent), neck (23 percent), upper extremity (22 percent), lower extremity (21 percent), and abdomen/pelvis (19 percent). The overall score on the competency test improved after completion of ASSET, with averages increasing from 62 ± 18 percent pretest to 71 ± 13 percent post-test (p < 0.001). CONCLUSIONS: After taking the ASSET course, military surgeons demonstrated improved knowledge and increased confidence in the operative skills taught in the course. The ASSET course may provide sustainment of knowledge and confidence if used at regular intervals to maintain trauma skills and deployment readiness.

The last days: The medical response of United States and allied military teams during the Afghanistan Exodus.

OBJECTIVES: The objective of this study is to describe the United States and allied military medical response during the withdrawal from Afghanistan. BACKGROUND: The military withdrawal from Afghanistan concluded with severe hostilities resulting in numerous civilian and military casualties. The clinical care provided by coalition forces capitalized on decades of lessons learned and enabled unprecedented accomplishments. METHODS: In this retrospective, observational analysis, casualty numbers, and operative information was collected and reported from military medical assets in Kabul, Afghanistan. The continuum of medical care and the trauma system, from the point of injury back to the United States was captured and described. RESULTS: Prior to a large suicide bombing resulting in a mass casualty event, the international medical teams managed distinct 45 trauma incidents involving nearly 200 combat and non-combat civilian and military patients over the preceding 3 months. Military medical personnel treated 63 casualties from the Kabul airport suicide attack and performed 15 trauma operations. US air transport teams evacuated 37 patients within 15 hours of the attack. CONCLUSION: Lessons learned from the last 20 years of combat casualty care were successfully implemented during the culmination of the Afghanistan conflict. Ultimately, the effort, teamwork, and system adaptability exemplify not only the attitudes and character of service members who provide modern combat casualty care but also the paramount importance of the battlefield learning health care system. A continued posture to maintain military surgical preparedness in unique environments remain crucial as the US military prepares for the future.Retrospective observational analysis. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level V.

Dunning-Kruger Effect Between Self-Peer Ratings of Surgical Performance During a MASCAL Event and Pre-Event Assessed Trauma Procedural Capabilities.

Objectives: The research question asked to what extent do self-rated performance scores of individual surgeons correspond to assessed procedural performance abilities and to peer ratings of procedural performance during a mass casualty (MASCAL) event? Background: Self-assessment using performance rating scales is ubiquitous in surgical education as a proxy for direct measurement of competence. The validity and reliability of self-ratings as competency measures are susceptible to cognitive biases such as Dunning-Kruger effects, which describe how individuals over/underestimate their own performance compared to assessments from independent sources. The ability of surgeons to accurately self-assess their procedural performance remains undetermined. Methods: A purposive sample of military surgeons (N = 13) who collectively cared for trauma patients during a MASCAL event participated in the study. Pre-event performance assessment scores for 32 trauma procedures were compared with post-event self and peer performance ratings using F tests (P < 0.05) and effect sizes (Cohen's d). Results: There were no significant differences between peer ratings and performance assessment scores. There were significant differences between self-ratings and both peer ratings (P < 0.001) and performance assessment scores (P < 0.001). Effect sizes were very large for self to peer rating comparison (Cohen's d = 2.34) and self to performance assessment comparison (Cohen's d = 2.77). Conclusions: The outcomes demonstrate that self-ratings were significantly lower than the independently determined assessment scores for each surgeon, revealing a Dunning-Kruger effect for highly skilled individuals underestimating their abilities. These outcomes underscore the limitations of self-assessment for measuring competence.

Nuclear factor-kappaB mediates the inhibitory effects of tumor necrosis factor-alpha on growth hormone-inducible gene expression in liver.

TNF inhibits serine protease inhibitor 2.1 (Spi 2.1) and IGF-I gene expression by GH in CWSV-1 hepatocytes. The current study describes construction of a GH-inducible IGF-I promoter construct and investigates mechanisms by which TNF and nuclear factor-kappaB (NFkappaB) inhibit GH-inducible gene expression. CWSV-1 cells were transfected with GH-inducible Spi 2.1 or IGF-I promoter luciferase constructs, incubated with TNF signaling inhibitors (fumonisin B1 for sphingomyelinase and SP600125 for c-Jun N-terminal kinase), treated with or without TNF, and then stimulated with recombinant human GH. The 5- to 6-fold induction of Spi 2.1 and IGF-I promoter activity by GH was inhibited by TNF. Neither fumonisin B1 nor SP600125 prevented the inhibitory effects of TNF on GH-inducible promoter activity. Dominant-negative inhibitor-kappaBalpha (IkappaBalpha) expression vectors (IkappaBalphaS/A or IkappaBalphaTrunc), p65 and p50 expression vectors, and p65 deletion constructs were used to investigate the NFkappaB pathway. IkappaBalphaS/A and IkappaBalphaTrunc ameliorated the inhibitory effects of TNF on GH-inducible Spi 2.1 and IGF-I promoter activity. Cotransfection of CWSV-1 cells with expression vectors for p65 alone or p50 and p65 together inhibited GH-inducible Spi 2.1 and IGF-I promoter activity. Cotransfection with a C-terminal p65 deletion (1-450) enhanced GH-inducible promoter activity, whereas the N-terminal deletion (31-551) was inhibitory for IGF-I but not Spi 2.1. Cycloheximide did not antagonize the inhibitory effects of TNF on GH-inducible IGF-I expression. We conclude the inhibitory effects of TNF on GH-inducible promoter activity are mediated by NFkappaB, especially p65, by a mechanism that does not require protein synthesis.

Interleukin-6 inhibits growth hormone-mediated gene expression in hepatocytes.

During systemic inflammation, the liver becomes unresponsive to growth hormone (GH), resulting in decreased plasma insulin-like growth factor-I (IGF-I) with concomitant reductions in lean body mass. Transgenic mice that overexpress IL-6 also demonstrate impaired growth and decreased IGF-I. To determine whether IL-6 directly inhibits GH-inducible gene expression, CWSV-1 hepatocytes were incubated with IL-6 (10 ng/ml), then stimulated with recombinant human GH (500 ng/ml, 18 h). The increase in IGF-I and serine protease inhibitor 2.1 (Spi 2.1) mRNA in GH-treated cells was inhibited by treatment with IL-6 for 24 h. To investigate potential mechanisms, we examined the effects of IL-6 on GH receptor (GHR) expression and GH signaling via the JAK/signal transducer and activator of transcription (STAT) and MAP kinase pathways. Incubation of cells with IL-6 (10 ng/ml, 24 h) had no effect on GHR abundance or signaling proteins JAK2, STAT5b, and ERK1/2. Although GH transiently increased (2- to 5-fold) the tyrosine phosphorylation of GHR, JAK2, STAT5b, and ERK1/2, IL-6 did not alter these phosphorylation events. However, nuclear protein from IL-6-treated cells demonstrated reduced STAT5 DNA binding (by EMSA) at 15 min (-20%) and 60 min (-43%) after GH stimulation. To determine whether IL-6 inhibits GH-inducible promoter activity, CWSV-1 cells were transfected with Spi 2.1 or prolactin receptor promoter luciferase vectors, incubated with or without IL-6, then stimulated with GH. The induction of both Spi 2.1 (7.5-fold) and prolactin receptor (4-fold) promoter activity by GH was inhibited by IL-6. In summary, IL-6 mediates hepatic GH resistance by a time-dependent inhibition of GH-inducible promoter activity that is associated with reductions in STAT5 DNA binding.