Propensity weighted analysis of chemical venous thromboembolism prophylaxis agents in isolated severe traumatic brain injury: An EAST sponsored multicenter study.

BACKGROUND: In patients with severe traumatic brain injury (TBI), clinicians must balance preventing venous thromboembolism (VTE) with the risk of intracranial hemorrhagic expansion (ICHE). We hypothesized that low molecular weight heparin (LMWH) would not increase risk of ICHE or VTE as compared to unfractionated heparin (UH) in patients with severe TBI. METHODS: Patients ≥ 18 years of age with isolated severe TBI (AIS ≥ 3), admitted to 24 level I and II trauma centers between January 1, 2014 to December 31, 2020 and who received subcutaneous UH and LMWH injections for chemical venous thromboembolism prophylaxis (VTEP) were included. Primary outcomes were VTE and ICHE after VTEP initiation. Secondary outcomes were mortality and neurosurgical interventions. Entropy balancing (EBAL) weighted competing risk or logistic regression models were estimated for all outcomes with chemical VTEP agent as the predictor of interest. RESULTS: 984 patients received chemical VTEP, 482 UH and 502 LMWH. Patients on LMWH more often had pre-existing conditions such as liver disease (UH vs LMWH 1.7 % vs. 4.4 %, p = 0.01), and coagulopathy (UH vs LMWH 0.4 % vs. 4.2 %, p < 0.001). There were no differences in VTE or ICHE after VTEP initiation. There were no differences in neurosurgical interventions performed. There were a total of 29 VTE events (3 %) in the cohort who received VTEP. A Cox proportional hazards model with a random effect for facility demonstrated no statistically significant differences in time to VTE across the two agents (p = 0.44). The LMWH group had a 43 % lower risk of overall ICHE compared to the UH group (HR = 0.57: 95 % CI = 0.32-1.03, p = 0.062), however was not statistically significant. CONCLUSION: In this multi-center analysis, patients who received LMWH had a decreased risk of ICHE, with no differences in VTE, ICHE after VTEP initiation and neurosurgical interventions compared to those who received UH. There were no safety concerns when using LMWH compared to UH. LEVEL OF EVIDENCE: Level III, Therapeutic Care Management.

Interpersonal Violence and Social Determinants of Health.

Social determinants of health (SDOH) influence patient outcomes and risk assessment. This study focuses on interpersonal violence, trauma outcomes, and SDOH. We hypothesized patients with lower SDOH experience worse trauma outcomes and present from higher-risk communities. Demographics, SDOH, and outcomes for patients admitted to surgical trauma suffering interpersonal violence were collected and analyzed. Home addresses were plotted, identifying areas of need compared with Area Deprivation Index (ADI). Only 18.8% of patients had documented SDOH, yielding small sample size. Analysis revealed no statistically significant associations (P < .05) between SDOH and trauma outcomes, including ICU length of stay and stress concern (P = .0804). Heat mapping revealed several hot spots across our catchment area, correlating with higher-ranked ADIs and increased deprivation. This study demonstrated SDOH can bring value in determining patient risk, emphasizing resource dedication to documenting these factors. Home addresses in conjunction with ADIs can ascertain areas for resource allocation within communities.

Acquired Methemoglobinemia in the Surgical Intensive Care Unit.

Acquired methemoglobinemia is a potentially lethal medical condition caused by exposure to oxidizing xenobiotics, including antibiotics such as dapsone and inhaled anesthetics such as benzocaine. In this case report, we describe two presentations of acquired methemoglobinemia which presented to our surgical intensive care unit within one month. This highlights the potential connection between an emergent surgery or procedure and the development of methemoglobinemia in an environment where it is presumed that this condition would be extremely rare. High clinical suspicion for methemoglobinemia is warranted if the patient develops cyanosis or a decreased oxygen saturation unresponsive to supplemental oxygen when another etiology is not identifiable. If methemoglobinemia is suspected, a direct measurement of blood methemoglobin levels can be obtained to confirm the diagnosis. Prompt treatment with intravenous methylene blue is highly effective.

Early VTE prophylaxis in severe traumatic brain injury: A propensity score weighted EAST multicenter study.

BACKGROUND: Patients with traumatic brain injury (TBI) are at high risk of venous thromboembolism events (VTE). We hypothesized that early chemical VTE prophylaxis initiation (≤24 hours of a stable head CT) in severe TBI would reduce VTE without increasing risk of intracranial hemorrhage expansion (ICHE). METHODS: A retrospective review of adult patients 18 years or older with isolated severe TBI (Abbreviated Injury Scale score, ≥ 3) who were admitted to 24 Level I and Level II trauma centers from January 1, 2014 to December 31 2020 was conducted. Patients were divided into those who did not receive any VTE prophylaxis (NO VTEP), who received VTE prophylaxis ≤24 hours after stable head CT (VTEP ≤24) and who received VTE prophylaxis >24 hours after stable head CT (VTEP>24). Primary outcomes were VTE and ICHE. Covariate balancing propensity score weighting was utilized to balance demographic and clinical characteristics across three groups. Weighted univariate logistic regression models were estimated for VTE and ICHE with patient group as predictor of interest. RESULTS: Of 3,936 patients, 1,784 met inclusion criteria. Incidences of VTE was significantly higher in the VTEP>24 group, with higher incidences of DVT in the group. Higher incidences of ICHE were observed in the VTEP≤24 and VTEP>24 groups. After propensity score weighting, there was a higher risk of VTE in patients in VTEP >24 compared with those in VTEP≤24 (odds ratio, 1.51; 95% confidence interval, 0.69-3.30; p = 0.307), however was not significant. Although, the No VTEP group had decreased odds of having ICHE compared with VTEP≤24 (odds ratio, 0.75; 95% confidence interval, 0.55-1.02, p = 0.070), the result was not statistically significant. CONCLUSION: In this large multi-center analysis, there were no significant differences in VTE based on timing of initiation of VTE prophylaxis. Patients who never received VTE prophylaxis had decreased odds of ICHE. Further evaluation of VTE prophylaxis in larger randomized studies will be necessary for definitive conclusions. LEVEL OF EVIDENCE: Therapeutic Care Management; Level III.

Significant Hypophosphatemia Is Predictive of Brain Death in Severe Traumatic Brain Injury.

Traumatic brain injury (TBI) is one of the most common causes of morbidity and mortality worldwide. Severe TBI carries the greatest risk of brain death progression. There are currently no laboratory markers that predict patient's outcome. We hypothesize that the degree of hypophosphatemia (HP) in TBI is an indicator for progression to brain death. A total of 336 patients, ages 15-89, with a GCS of 8 or less at admission were identified and retrospectively analyzed. Demographics, laboratory studies, and brain death (BD) were collected. Univariate analysis demonstrated HP was correlated with BD (P < .0002). Multivariate analysis showed that phosphate was the only measured electrolyte correlated to BD with a P value < .0001. Mechanism of hypophosphatemia may be related to BD progression and provide future areas for study.

Prolonged exposure to simulated microgravity diminishes dendritic cell immunogenicity.

Immune dysfunction due to microgravity remains a hurdle in the next step of human space exploration. Dendritic cells (DC) represent a critical component of immunity, given their role in the detection of invaders and the subsequent task of activating T cells to respond and eliminate the threat. Upon encounter with microbes, DC undergo a process of maturation, whereby the cells upregulate the expression of surface proteins and secrete cytokines, both required for the optimal activation of CD4+ and CD8+ T cells. In this study, DC were cultured from 2-14 days in a rotary cell culture system, which generates a simulated microgravity (SMG) environment, and then the cells were assessed for maturation status and the capacity to activate T cells. Short-term culture (<72 h) of DC in SMG resulted in an increased expression of surface proteins associated with maturation and interleukin-6 production. Subsequently, the SMG exposed DC were superior to Static control DC at activating both CD4+ and CD8+ T cells as measured by interleukin-2 and interferon-γ production, respectively. However, long-term culture (4-14 d) of DC in SMG reduced the expression of maturation markers and the capacity to activate T cells as compared to Static DC controls.