Population pharmacokinetic modelling and simulation of tranexamic acid in adult trauma patients.

AIMS: The aim of this study is to describe the disposition of tranexamic acid (TXA) in adult trauma patients and derive a dosing regimen that optimizes exposure based on a predefined exposure target. METHODS: We performed a population pharmacokinetic (popPK) analysis of participants enrolled in the Tranexamic Acid Mechanisms and Pharmacokinetics in Traumatic Injury (TAMPITI) trial (≥18 years with traumatic injury, given ≥1 blood product and/or requiring immediate transfer to the operating room) who were randomized to a single dose of either 2 or 4 g of TXA ≤2 h from time of injury. PopPK analysis was conducted using nonlinear mixed-effects modelling (NONMEM). Simulations were then performed using the final model to generate estimated plasma TXA concentrations in 1000 simulated participants. Dosing schemes were evaluated to determine maintenance of TXA plasma concentrations >10 mg/L for ≥8 h after administration of the initial dose. RESULTS: TXA PK was best described by a two-compartment model with proportional residual error and allometric scaling on all parameters. Platelet count, skeletal muscle oxygen saturation measured by near-infrared spectroscopy and interleukin-8 concentration were significant covariates on TXA clearance. Based on simulations, a 2 g IV bolus dose, repeated 3 h later, best achieved the target exposure. CONCLUSIONS: According to simulations from a popPK model of TXA, a 2 g IV bolus with a repeated dose 3 h later would be most likely to maintain concentrations >10 mg/L for 8 h in >95% of adult trauma patients and should be considered for patients with ongoing haemorrhage.

Sigh Ventilation in Patients With Trauma: The SiVent Randomized Clinical Trial.

Importance: Among patients receiving mechanical ventilation, tidal volumes with each breath are often constant or similar. This may lead to ventilator-induced lung injury by altering or depleting surfactant. The role of sigh breaths in reducing ventilator-induced lung injury among trauma patients at risk of poor outcomes is unknown. Objective: To determine whether adding sigh breaths improves clinical outcomes. Design, Setting, and Participants: A pragmatic, randomized trial of sigh breaths plus usual care conducted from 2016 to 2022 with 28-day follow-up in 15 academic trauma centers in the US. Inclusion criteria were age older than 18 years, mechanical ventilation because of trauma for less than 24 hours, 1 or more of 5 risk factors for developing acute respiratory distress syndrome, expected duration of ventilation longer than 24 hours, and predicted survival longer than 48 hours. Interventions: Sigh volumes producing plateau pressures of 35 cm H2O (or 40 cm H2O for inpatients with body mass indexes >35) delivered once every 6 minutes. Usual care was defined as the patient's physician(s) treating the patient as they wished. Main Outcomes and Measures: The primary outcome was ventilator-free days. Prespecified secondary outcomes included all-cause 28-day mortality. Results: Of 5753 patients screened, 524 were enrolled (mean [SD] age, 43.9 [19.2] years; 394 [75.2%] were male). The median ventilator-free days was 18.4 (IQR, 7.0-25.2) in patients randomized to sighs and 16.1 (IQR, 1.1-24.4) in those receiving usual care alone (P = .08). The unadjusted mean difference in ventilator-free days between groups was 1.9 days (95% CI, 0.1 to 3.6) and the prespecified adjusted mean difference was 1.4 days (95% CI, -0.2 to 3.0). For the prespecified secondary outcome, patients randomized to sighs had 28-day mortality of 11.6% (30/259) vs 17.6% (46/261) in those receiving usual care (P = .05). No differences were observed in nonfatal adverse events comparing patients with sighs (80/259 [30.9%]) vs those without (80/261 [30.7%]). Conclusions and Relevance: In a pragmatic, randomized trial among trauma patients receiving mechanical ventilation with risk factors for developing acute respiratory distress syndrome, the addition of sigh breaths did not significantly increase ventilator-free days. Prespecified secondary outcome data suggest that sighs are well-tolerated and may improve clinical outcomes. Trial Registration: ClinicalTrials.gov Identifier: NCT02582957.

The risk of thromboembolic events with early intravenous 2- and 4-g bolus dosing of tranexamic acid compared to placebo in patients with severe traumatic bleeding: A secondary analysis of a randomized, double-blind, placebo-controlled, single-center trial.

BACKGROUND: Screening for the risk of thromboembolism (TE) due to tranexamic acid (TXA) in patients with severe traumatic injury has not been performed in randomized clinical trials. Our objective was to determine if TXA dose was independently-associated with thromboembolism. STUDY DESIGN AND METHODS: This is a secondary analysis of a single-center, double-blinded, randomized controlled trial comparing placebo to a 2-g or 4-g intravenous TXA bolus dose in trauma patients with severe injury. We used multivariable discrete-time Cox regression models to identify associations with risk for thromboembolic events within 30 days post-enrollment. Event curves were created using discrete-time Cox regression. RESULTS: There were 50 patients in the placebo group, 49 in the 2-g, and 50 in the 4-g TXA group. In adjusted analyses for thromboembolism, a 2-g dose of TXA had an hazard ratio (HR, 95% confidence interval [CI]) of 3.20 (1.12-9.11) (p = .029), and a 4-g dose of TXA had an HR (95% CI) of 5.33 (1.94-14.63) (p = .001). Event curves demonstrated a higher probability of thromboembolism for both doses of TXA compared to placebo. Other parameters independently associated with thromboembolism include time from injury to TXA administration, body mass index, and total blood products transfused. DISCUSSION: In patients with severe traumatic injury, there was a dose-dependent increase in the risk of at least one thromboembolic event with TXA. TXA should not be withheld, but thromboembolism screening should be considered for patients receiving a dose of at least 2-g TXA intravenously for traumatic hemorrhage.

Effect of P2Y12 Inhibitors on Survival Free of Organ Support Among Non-Critically Ill Hospitalized Patients With COVID-19: A Randomized Clinical Trial.

Importance: Platelets represent a potential therapeutic target for improved clinical outcomes in patients with COVID-19. Objective: To evaluate the benefits and risks of adding a P2Y12 inhibitor to anticoagulant therapy among non-critically ill patients hospitalized for COVID-19. Design, Setting, and Participants: An open-label, bayesian, adaptive randomized clinical trial including 562 non-critically ill patients hospitalized for COVID-19 was conducted between February 2021 and June 2021 at 60 hospitals in Brazil, Italy, Spain, and the US. The date of final 90-day follow-up was September 15, 2021. Interventions: Patients were randomized to a therapeutic dose of heparin plus a P2Y12 inhibitor (n = 293) or a therapeutic dose of heparin only (usual care) (n = 269) in a 1:1 ratio for 14 days or until hospital discharge, whichever was sooner. Ticagrelor was the preferred P2Y12 inhibitor. Main Outcomes and Measures: The composite primary outcome was organ support-free days evaluated on an ordinal scale that combined in-hospital death (assigned a value of -1) and, for those who survived to hospital discharge, the number of days free of respiratory or cardiovascular organ support up to day 21 of the index hospitalization (range, -1 to 21 days; higher scores indicate less organ support and better outcomes). The primary safety outcome was major bleeding by 28 days as defined by the International Society on Thrombosis and Hemostasis. Results: Enrollment of non-critically ill patients was discontinued when the prespecified criterion for futility was met. All 562 patients who were randomized (mean age, 52.7 [SD, 13.5] years; 41.5% women) completed the trial and 87% received a therapeutic dose of heparin by the end of study day 1. In the P2Y12 inhibitor group, ticagrelor was used in 63% of patients and clopidogrel in 37%. The median number of organ support-free days was 21 days (IQR, 20-21 days) among patients in the P2Y12 inhibitor group and was 21 days (IQR, 21-21 days) in the usual care group (adjusted odds ratio, 0.83 [95% credible interval, 0.55-1.25]; posterior probability of futility [defined as an odds ratio <1.2], 96%). Major bleeding occurred in 6 patients (2.0%) in the P2Y12 inhibitor group and in 2 patients (0.7%) in the usual care group (adjusted odds ratio, 3.31 [95% CI, 0.64-17.2]; P = .15). Conclusions and Relevance: Among non-critically ill patients hospitalized for COVID-19, the use of a P2Y12 inhibitor in addition to a therapeutic dose of heparin, compared with a therapeutic dose of heparin only, did not result in an increased odds of improvement in organ support-free days within 21 days during hospitalization. Trial Registration: ClinicalTrials.gov Identifier: NCT04505774.

Pseudomonas aeruginosa Pneumonia Causes a Loss of Type-3 and an Increase in Type-1 Innate Lymphoid Cells in the Gut.

BACKGROUND: Sepsis induces gut barrier dysfunction characterized by increased gut epithelial apoptosis and increased intestinal permeability. The cytokine IL-22 has been demonstrated to regulate gut barrier function. Type-3 innate lymphoid cells (ILC3) are the predominate source of IL-22 in the GI tract. We hypothesized that sepsis may cause changes to the gut ILC3/IL-22 axis. MATERIALS AND METHODS: Sepsis was induced in WT and IL-22 KO mice by Pseudomonas aeruginosa pneumonia. Changes in gut-associated leukocyte populations were determined by flow-cytometry and ILC-associated transcripts were measured by RT-PCR. The effect of sepsis on gut permeability, pulmonary microbial burden, gut epithelial apoptosis, and survival was compared between WT and IL-22-/- mice. RESULTS: Sepsis resulted in a significant decrease in the number of ILC3 in the gut, with a reciprocal increase in type-1 ILC (ILC1). Consistent with prior reports, sepsis was associated with increased gut permeability; however there was no difference in gut permeability, gut epithelial apoptosis, pulmonary microbial burden, or survival between WT and IL-22-/- mice. CONCLUSIONS: Septic pneumonia causes a decrease in gut-associated ILC3 and an associated reciprocal increase in ILC1. This may reflect inflammation-induced conversion of ILC3 to ILC1. Constitutive systemic IL-22 deficiency does not alter sepsis-induced gut barrier dysfunction.

Trauma Induces Emergency Hematopoiesis through IL-1/MyD88-Dependent Production of G-CSF.

The inflammatory response to infection or injury dramatically increases the hematopoietic demand on the bone marrow to replace effector leukocytes consumed in the inflammatory response. In the setting of infection, pathogen-associated molecular patterns induce emergency hematopoiesis, activating hematopoietic stem and progenitor cells to proliferate and produce progeny for accelerated myelopoiesis. Sterile tissue injury due to trauma also increases leukocyte demand; however, the effect of sterile tissue injury on hematopoiesis is not well described. We find that tissue injury alone induces emergency hematopoiesis in mice subjected to polytrauma. This process is driven by IL-1/MyD88-dependent production of G-CSF. G-CSF induces the expansion of hematopoietic progenitors, including hematopoietic stem cells and multipotent progenitors, and increases the frequency of myeloid-skewed progenitors. To our knowledge, these data provide the first comprehensive description of injury-induced emergency hematopoiesis and identify an IL-1/MyD88/G-CSF-dependent pathway as the key regulator of emergency hematopoiesis after injury.

The use of low-titer group O whole blood is independently associated with improved survival compared to component therapy in adults with severe traumatic hemorrhage.

BACKGROUND: There is a resurgence in the use of low-titer group O whole blood (LTOWB) for hemorrhagic shock. We hypothesized the use of LTOWB compared to component therapy (CT) would be independently associated with improved 24-hour mortality. STUDY DESIGN AND METHODS: In this prospective observational study, trauma patients 18 years of age or older with massive transfusion protocol activations were included from August 17, 2018, to May 14, 2019. The primary outcome was 24-hour mortality. Secondary outcomes included 72-hour blood product totals, multiple organ dysfunction scores (MODS), and 28-day mortality. Multivariable logistic regression (MVLR) and Cox regression were performed to determine independent associations. RESULTS: There were no clinically meaningful differences in measures of injury severity between study groups (CT, n = 42; LTOWB, n = 44). There was no difference in MODS between study groups. The unadjusted mortality was not statistically different between the study groups (9/42 [21%] for CT vs. 7/44 [16%] for LTOWB; p = 0.518). In the MVLR model, LTOWB increased the odds of 24-hour survival by 23% (odds ratio 0.81, 95% confidence interval 0.69-0.96; p = 0.017). Adjusted survival curve analysis indicated improved survival at both 24 hours and 28 days for LTOWB patients (p < 0.001). Further stratification showed an association between LTOWB use and survival when maximum clot firmness (MCF) was 60 mm or less (p = 0.009). CONCLUSIONS: The use of LTOWB is independently associated with improved 24-hour and 28-day survival, and does not increase organ dysfunction at 72 hours. Use of LTOWB most impacted survival of patients with reduced clot firmness (MCF ≤60 mm). Collectively, these data support the clinical use and continued study of LTOWB for hemostatic resuscitation.

Evaluation of the safety and efficacy of a new hemostatic powder using a quantitative surface bleeding severity scale.

AIMS OF THE STUDY: The safety and efficacy of a hemostatic powder (HP) versus a control agent, absorbable gelatin sponge and thrombin (G + T), were assessed, using a validated, quantitative bleeding severity scale. METHODS: Subjects were randomized to receive HP (256 subjects) or G + T (132 subjects) for treatment of minimal, mild, or moderate bleeding at 20 investigational sites. The primary efficacy endpoint was non-inferiority of HP relative to G + T for success at achieving hemostasis within 6 minutes. Secondary endpoints in rank order included: superiority of HP relative to G + T in mean preparation time; non-inferiority of HP relative to G + T for achieving hemostasis within 3 min; superiority of HP relative to G + T for achieving hemostasis within 6 min; and superiority of HP relative to G + T for success for achieving hemostasis within 3 min. RESULTS: A total of 388 subjects were included in the primary efficacy analysis. At 6 min, hemostasis was achieved in 93.0% (238/256) of the HP group compared to 77.3% (102/132) of the G + T group (non-inferiority P < 0.0001, superiority P < 0.0001). All secondary endpoints were met. Complications were comparable between treatment groups. CONCLUSIONS: HP had superior rates of hemostasis, shorter preparation time, and a similar safety profile compared to G + T in this prospective, randomized trial using quantitative bleeding severity criteria.

Incidence, demographics, and outcomes of nonoperative management of appendicitis in the United States.

BACKGROUND: Appendicitis is the most common intraabdominal surgical emergency in the United States, with over 250,000 cases each year. Several recent studies have evaluated the efficacy of nonoperative management of appendicitis. We measured changes in the treatment of appendicitis in the United States from 1998 to 2014 and evaluated outcomes in the contemporary cohort of appendicitis cases from 2010 to 2014. METHODS: The National Inpatient Sample was queried for cases with a principal diagnosis of appendicitis. Cases with peritoneal abscesses were excluded. We determined trends in management and then compared cases managed nonoperatively versus those managed with early operation for demographics and outcomes including mortality, total charges, and length of stay using univariate analysis, binary logistic regression analysis, and case-control matching. RESULTS: Although early operation remains the dominant treatment for acute appendicitis in the United States, there is an accelerating trend in nonoperative management. Nonoperative management is associated with increased age, number of comorbidities, and inpatient diagnoses. In univariate, multiple regression, and case-control analysis, nonoperative management is associated with decreased total charges but significantly increased risk of mortality. CONCLUSIONS: Elderly patients and patients with medical comorbidities are more likely to be treated nonoperatively for appendicitis than younger patients. Although previously published data support nonoperative management of appendicitis in low-risk surgical patients, we suggest that elderly or medically complex patients may benefit from early operative treatment of appendicitis and are potentially at risk of poor outcomes from nonoperative management.

Surgical adjuncts to noncompressible torso hemorrhage as tools for patient blood management.

Despite the tremendous advances and successes in the care of combat casualties over the past 15 years of war, noncompressible torso hemorrhage (NCTH) remains the most likely source of potentially preventable death (approx. 25%) on the battlefield. This is also likely true for civilian victims of blunt and penetrating trauma. Various devices and therapeutic interventions have been, and are being, developed in an attempt to reduce morbidity and mortality for patients with NCTH. Examples include the use of prehospital blood and blood products, tranexamic acid, specially designed tourniquets for junctional hemorrhage control, retrograde endovascular balloon occlusion of the aorta, intracavity foam, expandable hemostatic sponges, and intravascular nanoparticles to suspended animation. Although each of these modalities offer the potential to staunch uncontrolled hemorrhage until an injured patient is able to reach definitive surgical care, further research and advances must be made to further reduce trauma morbidity and mortality and to identify those technologies and modalities that are best suited to rapid movement to the front lines of combat casualty care as well as to emergency medical personnel dealing with civilian trauma victims. The surgical adjuncts for NCTH discussed may all be considered as potential tools for patient blood management programs. If effective they offer the possibility of reduce hemorrhage and blood product exposure and improved patient outcomes.

A multicentre, prospective, randomized, controlled trial comparing EVARREST™ fibrin sealant patch to standard of care in controlling bleeding following elective hepatectomy: anatomic versus non-anatomic resection.

BACKGROUND: This multicentre, randomized clinical trial assessed the safety and effectiveness of the EVARREST™ Fibrin Sealant Patch (FP) in treating parenchymal bleeding following anatomic and non-anatomic liver resections. METHODS: One hundred and two patients were stratified according to the type of hepatic resection (anatomic/non-anatomic), and randomized (1:1) after identification of an appropriate bleeding site, to FP vs Standard of Care (SoC, manual compression ± topical haemostat). The primary endpoint was haemostasis at 4 min from bleeding site identification with no re-bleeding requiring re-treatment. RESULTS: The FP was superior in achieving haemostasis at 4 min (96%, 48/50) to SoC (46%, 24/52; p < 0.001). Stratification for resection type showed treatment differences for primary endpoint for anatomic (24/25 FP vs 13/23 SoC; p = 0.001) and non-anatomic liver resections (24/25FP vs 11/29 SoC; p < 0.001). Adverse events related to the study procedure were reported in 40/50 patients (80%) in the FP group and 43/52 patients (83%) in the SoC group. One (2%) adverse event (infected intra-abdominal fluid collection) was possibly related to study treatment. CONCLUSION: This clinical trial confirms that the FP is safe and highly effective in controlling parenchymal bleeding following hepatectomy regardless of the type of resection. ClinicalTrials.gov NCT01993888.

Doing more with less: low-titer group O whole blood resulted in less total transfusions and an independent association with survival in adults with severe traumatic hemorrhage.

BACKGROUND: Low-titer group O whole blood (LTOWB) or component therapy (CT) may be used to resuscitate hemorrhaging trauma patients. LTOWB may have clinical and logistical benefits and may improve survival. OBJECTIVES: We hypothesized LTOWB would improve 24-hour survival in hemorrhaging patients and would be safe and equally efficacious in non-group O compared with group O patients. METHODS: Adult trauma patients with massive transfusion protocol activations were enrolled in this observational study. The primary outcome was 24-hour mortality. Secondary outcomes included 72-hour total blood product use. A Cox regression determined the independent associations with 24-hour mortality. RESULTS: In total, 348 patients were included (CT, n = 180; LTOWB, n = 168). Demographics were similar between cohorts. Unadjusted 24-hour mortality was reduced in LTOWB vs CT: 8% vs 19% (P = .003), but 6-hour and 28-day mortality were similar. In an adjusted analysis with multivariable Cox regression, LTOWB was independently associated with reduced 24-hour mortality (hazard ratio, 0.21; 95% CI, 0.07-0.67; P = .004). LTOWB patients received significantly less 72-hour total blood products (80.9 [41.6-139.3] mL/kg vs 48.9 [25.9-106.9] mL/kg; P < .001). In stratified 24-hour survival analyses, LTOWB was associated with improved survival for patients in shock or with coagulopathy. LTOWB use in non-group O patients was not associated with increased mortality, organ injury, or adverse events. CONCLUSION: In this hypothesis-generating study, LTOWB use was independently associated with improved 24-hour survival, predominantly in patients with shock or coagulopathy. LTOWB also resulted in a 40% reduction in blood product use which equates to a median 2.4 L reduction in transfused products.

Does Negative Pressure Wound Therapy Impact the Outcome for Patients With Necrotizing Soft Tissue Infection Infected With Anaerobic Bacteria?

Background: A notable improvement in the treatment of necrotizing soft tissue infections (NSTIs) is the development of negative pressure wound therapy (NPWT). Clinicians are still debating whether NPWT is as successful as conventional wet-to-dry dressings at removing bacteria. Recent research has revealed potential oxygen deprivation effects of NPWT in underlying wound tissues, although clinical trials regarding the effects of reduced oxygen on anaerobic bacterial soft tissue infections remain noticeably lacking. Hypothesis: We hypothesized that NPWT-treated patients with NSTIs who were solely infected by anaerobic bacteria would have worse outcomes than those who were infected with other bacterial species. Patients and Methods: Our study included a retrospective examination of the 2008-2022 period of our Acute and Critical Care Surgery database. Patients who had been identified as having necrotizing fasciitis, Fournier gangrene, or gas gangrene and who had their conditions verified by positive wound cultures acquired during the initial debridement and subsequently received NPWT made up the study cohort. Comorbidities, surgical techniques, and clinical results were all covered by the data. Based on their wound infections, patients were divided into two groups: those with exclusively anaerobic NSTIs and those with different bacterial groups (such as polymicrobial and aerobic). Multiple regression, χ2 analysis, and analysis of variance (ANOVA) were among the analytical methods used. Results: One hundred twelve patients with NSTI who had received NPWT comprised the study cohort. Sixteen of these patients (14.3%) had NSTIs that were exclusively anaerobic, whereas the remaining 96 (85.7%) had NSTIs that were mixed aerobic, facultative, or polymicrobial. Between the two groups, there was no difference in the initial wound size. Patients with anaerobic NSTI who underwent NPWT showed a statistically significant increase in the number of debridements (3 [interquartile range {IQR},1-9] vs. 2 [IQR, 1-4]; p = 0.012) and an increased 100-day re-admission rate (37.5% vs. 12.5%; p = 0.012) when compared with patients with non-anaerobic NSTI. The 100-day re-admission rate increased three-fold in NPWT-treated anaerobic NSTIs, according to a logistic regression analysis (odds ratio [OR], 3.63; 95% confidence interval [CI], 1.06-12.44; p = 0.04). Conclusions: In contrast to patients with other bacterial strains, our data show that patients with NSTI treated with NPWT who only have anaerobic bacterial infections have a larger number of debridements and are much more likely to require re-admission within 100 days. We call for additional prospective studies to be conducted to identify additional risk factors and consider alternate treatment options for individuals with exclusively anaerobic NSTIs in light of these findings.

Negative Pressure Wound Therapy With and Without Instillation in Necrotizing Soft Tissue Infections.

Background: Necrotizing soft tissue infections (NSTIs) are rare but deadly infections that require early and often extensive surgical debridement. After debridement, patients frequently have substantial morbidity because of large, open wounds. Hypothesis: Negative pressure wound therapy with instillation (NPWTi) results in higher wound closure rates compared with traditional negative pressure wound therapy (NPWT) or wet to dry dressings (moist wound care dressing). Patients and Methods: A prospectively maintained Acute and Critical Care Surgery database spanning 2008-2018 was queried for patients with a diagnosis of necrotizing fasciitis, Fournier gangrene, or gas gangrene. Data were collected on patient comorbidities, operative management, and clinical outcomes. Patients were stratified by use of moist wound care dressing, traditional NPWT, or NPWTi. Data were analyzed using analysis of variance (ANOVA), χ2, and logistic regression. Results: During the 10-year study period, patients were treated for NSTI; 173 were managed with moist wound care dressing, 150 with NPWT, and 48 with NPWTi. Patients were similar in terms of demographics, body mass index (BMI), diabetes mellitus, and smoking rates. Overall, complication rates were not substantially different, but mortality was higher in the moist wound care dressing group (16.2% vs. 10.7% NPWT vs. 2.1% NPWTi; p = 0.02). In the moist wound care dressing group, 81.5% of patients had an open wound at discharge compared with 52.7% of the NPWT group and only 14.6% of the NPWTi group (p < 0.001). On multivariable regression, NPWTi was associated with closure rates five times higher than the NPWT group (odds ratio [OR], 5.28; 95% confidence interval [CI], 2.40-11.61; p < 0.001) after controlling for smoking status, intravenous drug use, number of operations, and involvement of the most common region of the body. Conclusions: Negative pressure wound therapy with instillation is associated with higher rates of wound closure without increasing complication rates in patients with NSTI compared with traditional NPWT or moist wound care dressing. Although prospective studies are needed, this indicates the potential to improve patient quality of life through reduced pain and outpatient home health needs.

Trauma patients have reduced ex vivo flow-dependent platelet hemostatic capacity in a microfluidic model of vessel injury.

Trauma is the leading cause of death in individuals up to 45 years of age. Alterations in platelet function are a critical component of trauma-induced coagulopathy (TIC), yet these changes and the potential resulting dysfunction is incompletely understood. The lack of clinical assays available to explore platelet function in this patient population has hindered detailed understanding of the role of platelets in TIC. The objective of this study was to assess trauma patient ex vivo flow-dependent platelet hemostatic capacity in a microfluidic model. We hypothesized that trauma patients would have flow-regime dependent alterations in platelet function. Blood was collected from trauma patients with level I activations (N = 34) within 60 min of hospital arrival, as well as healthy volunteer controls (N = 10). Samples were perfused through a microfluidic model of injury at venous and arterial shear rates, and a subset of experiments were performed after incubation with fluorescent anti-CD41 to quantify platelets. Complete blood counts were performed as well as plasma-based assays to quantify coagulation times, fibrinogen, and von Willebrand factor (VWF). Exploratory correlation analyses were employed to identify relationships with microfluidic hemostatic parameters. Trauma patients had increased microfluidic bleeding times compared to healthy controls. While trauma patient samples were able to deposit a substantial amount of clot in the model injury site, the platelet contribution to microfluidic hemostasis was attenuated. Trauma patients had largely normal hematology and plasma-based coagulation times, yet had elevated D-Dimer and VWF. Venous microfluidic bleeding time negatively correlated with VWF, D-Dimer, and mean platelet volume (MPV), while arterial microfluidic bleeding time positively correlated with oxygenation. Arterial clot growth rate negatively correlated with red cell count, and positively with mean corpuscular volume (MCV). We observed changes in clot composition in trauma patient samples reflected by significantly diminished platelet contribution, which resulted in reduced hemostatic function in a microfluidic model of vessel injury. We observed a reduction in platelet clot contribution under both venous and arterial flow ex vivo in trauma patient samples. While our population was heterogenous and had relatively mild injury severity, microfluidic hemostatic parameters correlated with different patient-specific data depending on the flow setting, indicating potentially differential mechanistic pathways contributing to platelet hemostatic capacity in the context of TIC. These data were generated with the goal of identifying key features of platelet dysfunction in bleeding trauma patients under conditions of flow and to determine if these features correlate with clinically available metrics, thus providing preliminary surrogate markers of physiological platelet dysfunction to be further studied across larger cohorts. Future studies will continue to explore those relationships and further define mechanisms of TIC and their relationship with patient outcomes.

Prolonged hourly neurological examinations are associated with increased delirium and no discernible benefit in mild/moderate geriatric traumatic brain injury.

BACKGROUND: Serial neurological examinations (NEs) are routinely recommended in the intensive care unit (ICU) within the first 24 hours following a traumatic brain injury (TBI). There are currently no widely accepted guidelines for the frequency of NEs. Disruptions to the sleep-wake cycles increase the delirium rate. We aimed to evaluate whether there is a correlation between prolonged hourly (Q1)-NE and development of delirium and to determine if this practice reduces the likelihood of missing the detection of a process requiring emergent intervention. METHODS: A retrospective analysis of patients with mild/moderate TBI, admitted to the ICU with serial NEs, was performed. Cohorts were stratified by the duration of exposure to Q1-NE, into prolonged (≥24 hours) and nonprolonged (<24 hours). Our primary outcomes of interest were delirium, evaluated using the Confusion Assessment Method; radiological progression from baseline images; neurological deterioration (focal neurological deficit, abnormal pupillary examination, or Glasgow Coma Scale score decrease >2); and neurosurgical procedures. RESULTS: A total of 522 patients were included. No significant differences were found in demographics. Patients in the prolonged Q1-NE group (26.1%) had higher Injury Severity Score with similar head Abbreviated Injury Score, significantly higher delirium rate (59% vs. 35%, p < 0.001), and a longer hospital/ICU length of stay when compared with the nonprolonged Q1-NE group. No neurosurgical interventions were found to be performed emergently as a result of findings on NEs. Multivariate analysis demonstrated that prolonged Q1-NE was the only independent risk factor associated with a 2.5-fold increase in delirium rate. The number needed to harm for prolonged Q1-NE was 4. CONCLUSION: Geriatric patients with mild/moderate TBI exposed to Q1-NE for periods longer than 24 hours had nearly a threefold increase in ICU delirium rate. One of five patients exposed to prolonged Q1-NE is harmed by the development of delirium. No patients were found to directly benefit as a result of more frequent NEs. LEVEL OF EVIDENCE: Prognostic and Epidemiological; Level IV.

Prospective study examining clinical outcomes associated with a negative pressure wound therapy system and Barker's vacuum packing technique.

BACKGROUND: The open abdomen has become a common procedure in the management of complex abdominal problems and has improved patient survival. The method of temporary abdominal closure (TAC) may play a role in patient outcome. METHODS: A prospective, observational, open-label study was performed to evaluate two TAC techniques in surgical and trauma patients requiring open abdomen management: Barker's vacuum-packing technique (BVPT) and the ABThera(TM) open abdomen negative pressure therapy system (NPWT). Study endpoints were days to and rate of 30-day primary fascial closure (PFC) and 30-day all-cause mortality. RESULTS: Altogether, 280 patients were enrolled from 20 study sites. Among them, 168 patients underwent at least 48 hours of consistent TAC therapy (111 NPWT, 57 BVPT). The two study groups were well matched demographically. Median days to PFC were 9 days for NPWT versus 12 days for BVPT (p = 0.12). The 30-day PFC rate was 69 % for NPWT and 51 % for BVPT (p = 0.03). The 30-day all-cause mortality was 14 % for NPWT and 30 % for BVPT (p = 0.01). Multivariate logistic regression analysis identified that patients treated with NPWT were significantly more likely to survive than the BVPT patients [odds ratio 3.17 (95 % confidence interval 1.22-8.26); p = 0.02] after controlling for age, severity of illness, and cumulative fluid administration. CONCLUSIONS: Active NPWT is associated with significantly higher 30-day PFC rates and lower 30-day all-cause mortality among patients who require an open abdomen for at least 48 h during treatment for critical illness.

Reduction of Surgical Site Infection After Trauma Laparotomy Through Use of a Specific Protocol for Antibiotic Prophylaxis.

Background: Emergency laparotomy for abdominal trauma is associated with high rates of surgical site infection (SSI). A protocol for antimicrobial prophylaxis (AMP) for trauma laparotomy was implemented to determine whether SSI could be reduced by adhering to established principles of AMP. Patients and Methods: A protocol utilizing ertapenem administered immediately before initiation of trauma laparotomy was adopted. Compliance with measures of adequate AMP were determined before and after protocol implementation, as were rates of SSI and other infections related to abdominal trauma. Univariable and multivariable analyses were performed to determine risk factors for development of infection related to trauma laparotomy. Results: Over a four-year period, 320 patient operations were reviewed. Ertapenem use for prophylaxis increased to 54% in the post-intervention cohort. Compliance with individual measures of appropriate AMP improved modestly. Overall, infections related to trauma laparotomy decreased by 46% (absolute decrease of 13%) in the post-intervention cohort. Multivariable analysis confirmed that treatment during the post-intervention phase was associated with this decrease, with a separate analysis suggesting that ertapenem use was an important factor in this decrease. Conclusions: Development of a standardized protocol for AMP in trauma laparotomy led to decreases in infectious complications after that procedure.

Ludwig's Angina: Higher Incidence and Worse Outcomes Associated With the Onset of the Coronavirus Disease 2019 Pandemic.

Background: Ludwig's angina (LA) is a diffuse cellulitis of the submandibular space and adjacent tissues. During the coronavirus disease 2019 (COVID-19) pandemic, odontogenic treatments were often delayed because of the implementation of safety measures to avoid the spread of the virus. We hypothesized that delayed odontogenic treatments associated with the onset of the COVID-19 pandemic would be associated with an increase in the incidence of LA and worse outcomes related to these infections. Patients and Methods: Patients from June 2018 to June 2022 with computed tomography images suggestive of LA and confirmed by ear, nose, throat (ENT) consult were included. We abstracted demographics, outcomes, clinical management, and microbiology. Patients were stratified into pre-COVID and COVID-onset. Our primary outcome, incidence of LA, was defined as: (new LA cases) ÷ (ED evaluations of oral or dental infections × 1.5 years). Results: In the pre-COVID group, we identified 32 of 1,301 patients with LA for an incidence of 0.02 per year. The COVID-onset group consisted of 41 of 641 patients, with an incidence of 0.04 per year. In the COVID-onset group, progression to necrotizing fasciitis was more likely (0% vs. 15%; p < 0.024), and they returned to the operating room for repeated debridement (3% vs. 22%; p < 0.020). Likewise, hospital length of stay, intensive care unit (ICU) length of stay, and ventilator days were higher (4.3 ± 3.5 vs. 9.5 ± 11.3; 1.1 ± 1.2 vs. 9.5 ± 7.1; 0.3 ± 1 vs. 3.6 ± 7.1; p < 0.001). Conclusions: Although the prognosis for dental infections diagnosed early is generally favorable, we observed a notable increase in the incidence of LA after the onset of the COVID-19 pandemic. Moreover, complications stemming from these infections became more severe in the COVID-onset era. Specifically, the likelihood of necrotizing fasciitis showed a substantial increase, accompanied by an increased risk of respiratory failure and mediastinitis.