Gunshot Injuries to the Extremity: Is Immediate General Surgery Presence Needed?

Gunshot wounds (GSW) are becoming increasingly prevalent in urban settings. GSW to the trunk mandate full trauma activation and immediate surgeon response because of the high likelihood of operative intervention. Extremity GSW proximal to the knee/elbow also require full trauma activation based on American College of Surgeons Committee on trauma standards. However, whether isolated extremity GSW require frequent operative intervention is unclear. We evaluated GSW at our Level I trauma center from January 2012 to December 2016. Demographic data and injury patterns were abstracted from the trauma registry and charts. The number of GSW increased yearly but the age, gender, Injury Severity Score and injury pattern did not change (P = ns, not shown). There were 504 GSW that included an extremity and 194 (38%) involved multiple body regions. There were 310 GSW (62%) isolated to an extremity and 176 were proximal to the elbow/knee. If proximal GSW had an Emergency Department systolic blood pressure <90 mm Hg, 53 per cent underwent vascular repair, 12 per cent had soft tissue repair, and 29 per cent required no operation. If proximal GSW had an Emergency Department blood pressure >90 mm Hg, 57 per cent underwent orthopedic repair, 22 per cent required no surgery, and only 13 per cent required vascular repair (P < 0.01). In the absence of other criteria for full trauma activation such as shock, the need for the immediate presence of a general surgeon to perform emergency surgery for a GSW isolated to the extremity is low.

The use of ABC score in activation of massive transfusion: The yin and the yang.

BACKGROUND: Hemorrhage is the most common cause of early death in trauma patients. Massive transfusion protocols (MTPs) have been designed to accelerate the release of blood products but can result in waste if activated inappropriately. The Assessment of Blood Consumption (ABC) score has become a widely accepted score for MTP activation. In this study, we compared the use of ABC criteria to physician judgment in MTP activation. METHODS: Adult trauma patients treated at University of Louisville Trauma Center from January 2016 to December 2016 were studied. Activation via ABC score was assessed retrospectively from emergency department (ED) data. Location, timing of activation, percent of patients using more than 5 units of packed red blood cells, amount of product waste, factors associated with early activation by physicians, and mortality were analyzed. RESULTS: Three thousand four hundred twenty-one patients were included in this study. Only 33% of the patients who would have had MTP activation based on the ABC criteria used more than 5 units of blood products within 24 hours of admission compared with 65% of the patients in whom clinical judgment was used. Seventy-six percent of all MTP activations from clinical judgment would have been activated by the ABC criteria in the ED. Fifty-five percent of all MTP activations via clinical judgment were activated in the operating room and 41% in the ED. Eighty-one percent of activations that occurred in the operating room by physician judgment could have been activated earlier in the ED if the ABC criteria had been used. However, ABC score can lead to higher potential fresh frozen plasma waste (588 vs. 84 units) compared with physician judgment. CONCLUSIONS: The ABC criteria overestimate need for massive transfusion and can lead to increased product waste compared with physician judgment, but its use leads to earlier MTP activation. Criteria to trigger MT activation should rely on both clinical acumen and validated prediction tools. LEVEL OF EVIDENCE: Prognostic, level III.

c-Jun N-terminal kinase 1 is required for Toll-like receptor 1 gene expression in macrophages.

The regulation of innate immune responses to pathogens occurs through the interaction of Toll-like receptors (TLRs) with pathogen-associated molecular patterns and the activation of several signaling pathways whose contribution to the overall innate immune response to pathogens is poorly understood. We demonstrate a mechanism of control of murine macrophage responses mediated by TLR1/2 heterodimers through c-Jun N-terminal kinase 1 (JNK1) activity. JNK controls tumor necrosis factor alpha production and TLR-mediated macrophage responses to Borrelia burgdorferi, the causative agent of Lyme disease, and the TLR1/TLR2-specific agonist PAM(3)CSK(4). JNK1, but not JNK2, activity regulates the expression of the tlr1 gene in the macrophage cell line RAW264.7, as well as in primary CD11b(+) cells. We also show that the proximal promoter region of the human tlr1 gene contains an AP-1 binding site that is subjected to regulation by the kinase and binds two complexes that involve the JNK substrates c-Jun, JunD, and ATF-2. These results demonstrate that JNK1 regulates the response to TLR1/2 ligands and suggest a positive feedback loop that may serve to increase the innate immune response to the spirochete.