Cerebrospinal Fluid Cultures in Traumatic Brain Injury: Is It Worth It? A Two-Center Study.

Background: Patients with traumatic brain injury (TBI) frequently develop leukocytosis, fever, and tachycardia that may lead to extensive medical investigations to rule out an infectious process. Cerebrospinal fluid (CSF) is often acquired during this workup, however, the utility of this practice has not been studied previously. We hypothesized that CSF cultures would unlikely yield positive results in patients with TBI. Patients and Methods: A retrospective review was conducted of all patients with TBI admitted to two level 1 trauma centers at urban, academic institutions from January 2009 to December 2016. Data collected included patient demographics, presenting Glasgow Coma Score (GCS), injury profile, injury severity scores (ISS), regional abbreviated injury scale (AIS), hospital and intensive care unit (ICU) length of stay (LOS), ventilator days, and culture results. For purposes of the analysis, CSF cultures with Staphylococcus epidermidis, Staphylococcus aureus, or Candida underwent a chart review and were considered contaminates if indicated. Results: There were 145 patients who had CSF cultures obtained with a median age of 39 years; 77.2% were male. The majority of patients presented after blunt trauma with median GCS of 6, head AIS of 4, and ISS of 25. These patients had prolonged median ICU and hospital stays at 13 and 22 days, respectively. Six (4.1%) CSF cultures demonstrated growth. Four (2.8%) were deemed contaminants, with two growing Staphylococcus epidermidis only, one with both Staphylococcus epidermidis and Staphylococcus aureus, and one with Candida. Two cultures (1.4%) were positive and grew Enterobacter cloacae. Of note, both patients had prior instrumentation with an external ventricular drain. Conclusion: Obtaining CSF cultures in patients with TBI is of low yield, especially in patients without prior external ventricular drain. Other sources of infectious etiologies should be considered in this patient population.

Poor Corticospinal Motor Neuron Health Is Associated with Increased Symptom Severity in the Acute Phase Following Repetitive Mild TBI and Predicts Early ALS Onset in Genetically Predisposed Rodents.

Traumatic brain injury (TBI) is a well-established risk factor for several neurodegenerative disorders including Alzheimer's disease and Parkinson's disease, however, a link between TBI and amyotrophic lateral sclerosis (ALS) has not been clearly elucidated. Using the SOD1G93A rat model known to recapitulate the human ALS condition, we found that exposure to mild, repetitive TBI lead ALS rats to experience earlier disease onset and shortened survival relative to their sham counterparts. Importantly, increased severity of early injury symptoms prior to the onset of ALS disease symptoms was linked to poor health of corticospinal motor neurons and predicted worsened outcome later in life. Whereas ALS rats with only mild behavioral injury deficits exhibited no observable changes in corticospinal motor neuron health and did not present with early onset or shortened survival, those with more severe injury-related deficits exhibited alterations in corticospinal motor neuron health and presented with significantly earlier onset and shortened lifespan. While these studies do not imply that TBI causes ALS, we provide experimental evidence that head injury is a risk factor for earlier disease onset in a genetically predisposed ALS population and is associated with poor health of corticospinal motor neurons.

A Systems-based Approach to Reduce Deep Venous Thrombosis and Pulmonary Embolism in Trauma Patients.

BACKGROUND: Venous thromboembolism (VTE) in trauma patients carries significant morbidity and mortality. We previously described how titrating enoxaparin dosing by anti-Xa trough levels was associated with a lower VTE rate. We combined this strategy with a higher initial enoxaparin dose for a majority of patients and modified the electronic medical record (EMR) to encourage immediate dosing. We sought to determine if this systems-based approach was associated with a decrease in VTE rate. STUDY DESIGN: A retrospective review was conducted of all trauma patients on prophylactic enoxaparin at an academic, Level I Trauma Center from 01/2013 to 05/2014 (PRE) and 06/2015 to 02/2018 (POST). The patients in PRE were prescribed enoxaparin 30 mg twice daily without dose adjustments. The patients in POST received 40 mg twice daily unless exclusion criteria applied, with doses titrated to maintain anti-Xa trough levels between 0.1 and 0.2 IU/mL. RESULTS: There were 478 patients in the PRE and 1306 in the POST. Compared to PRE, POST patients were of similar age and were as likely to present after blunt trauma, although POST patients had lower injury severity scores (10 vs. 9, p < 0.01). The overall VTE rate was lower in POST (6.9% vs. 3.6%, p < 0.01). The adjusted risk of VTE (AOR 0.61, adjusted p = 0.04) was lower in POST and POST was independently protective for VTE (AOR 0.54; p = 0.01). CONCLUSION: By implementing system changes to improve enoxaparin dosing after trauma, a significant reduction in VTE rate was observed. Wider application of this strategy should be considered.

How repetitive traumatic injury alters long-term brain function.

BACKGROUND: How recurrent traumatic brain injury (rTBI) alters brain function years after insult is largely unknown. This study aims to characterize the mechanistic cause for long-term brain deterioration following rTBI using a rat model. METHODS: Eighteen Sprague-Dawley wild-type rats underwent bilateral rTBI using a direct skull impact device or sham treatment, once per week for 5 weeks, and were euthanized 56 weeks after the first injury. Weekly rotarod performance measured motor deficits. Beam walk and grip strength were also assessed. Brain tissue were stained and volume was computed using Stereo Investigator's Cavalieri Estimator. The L5 cortical layer proximal to the injury site was microdissected and submitted for sequencing with count analyzed using R "DESeq2" and "GOStats." Brain-derived neurotrophic factor (BDNF) levels were determined using enzyme-linked immunosorbent assay. RESULTS: Rotarod data demonstrated permanent deficits 1 year after rTBI. Decreased beam walk performance and grip strength was noted among rTBI rodents. Recurrent traumatic brain injury led to thinner cortex and thinner corpus callosum, enlarged ventricles, and differential expression of 72 genes (25 upregulated, 47 downregulated) including dysregulation of those associated with TBI (BDNF, NR4A1/2/3, Arc, and Egr) and downregulation in pathways associated with neuroprotection and neuroplasticity. Over the course of the study, BDNF levels decreased in both rTBI and sham rodents, and at each time point, the decrease in BDNF was more pronounced after rTBI. CONCLUSION: Recurrent traumatic brain injury causes significant long-term alteration in brain health leading to permanent motor deficits, cortical and corpus callosum thinning, and expansion of the lateral ventricles. Gene expression and BDNF analysis suggest a significant drop in pathways associated with neuroplasticity and neuroprotection. Although rTBI may not cause immediate neurological abnormalities, continued brain deterioration occurs after the initial trauma in part due to a decline in genes associated with neuroplasticity and neuroprotection.

The Impact of IV Electrolyte Replacement on the Fluid Balance of Critically Ill Surgical Patients.

Avoiding excess fluid administration is necessary when managing critically ill surgical patients. The aim of this study was to delineate the current practices of IV electrolyte (IVE) replacement in a surgical ICU and quantify their contribution to the fluid balance (FB) status. Patients admitted to the surgical ICU over a six-month period were reviewed. Patients undergoing dialysis and those with ICU stay <72 hours were excluded. A total of 248 patients were included. The median age was 60 years, and 57 per cent were male. Overall, 1131 patient ICU days were analyzed. The median daily FB was 672 mL. IVEs were administered in 62 per cent of ICU days. In days that IVEs were used, negative FB was significantly less likely to be achieved (62% vs 69%, P = 0.02). The most commonly administered IVE was calcium (32% of ICU days); however, the largest volume of IVE was administered in the form of phosphorus (median 225 mL). Diuretics were administered in 17 per cent of ICU days. Patients who received diuretics were significantly more likely to receive IVE (70% vs 61%, P = 0.02). Administration of IVE may contribute to the daily positive FB of surgical ICU patients. Implementation of practices that can ameliorate this effect is encouraged.

What Happens After a Stop the Bleed Class? The Contrast Between Theory and Practice.

OBJECTIVE: The Department of Homeland Security launched the Stop the Bleed initiative, a campaign intended to teach bystanders hemorrhage control strategies. Despite the program's popularity, little is known about actions taken by participants afterwards. We sought to determine how often participants acquired the equipment that is necessary in applying the skills taught. DESIGN: A standardized survey instrument was distributed to all American College of Surgeons Bleeding Control Basic (B-Con) class participants from 05/2017 to 01/2018. The instrument queried about the likelihood of applying skills and obtaining materials. A web-based survey was administered one month later inquiring whether materials were obtained and barriers that would prohibit acquisition. SETTING: Academic, urban, Level I trauma center. PARTICIPANTS: Healthcare and nonhealthcare personnel. RESULTS: There were 336 and 183 participants who completed the initial and subsequent web-based survey, respectively. Participants indicated a high likelihood of applying a tourniquet (95.5%), applying pressure (97.9%), and packing a wound (96.4%), if required. Additionally, 74.7% and 76.2% reported a high likelihood of obtaining a tourniquet and packing material, respectively. However, only 21.3% and 50.8% obtained a tourniquet and packing material, respectively, 1 month later. Cost, time, and accessibility of items during a time of need were cited to be common reasons for not obtaining these materials. CONCLUSIONS: Despite reporting a high likelihood of utilizing hemorrhage control skills upon completion of the B-Con class, few went on to acquire the materials needed to apply these skills among those who responded. These results may be impacted by loss of follow up and response bias. Developing strategies that allow for easy access to materials is imperative and may lead to both better implementation of the purposes of the program and improved dissemination of its principles within the community.

Interactions between the Ig-Superfamily Proteins DIP-α and Dpr6/10 Regulate Assembly of Neural Circuits.

Drosophila Dpr (21 paralogs) and DIP proteins (11 paralogs) are cell recognition molecules of the immunoglobulin superfamily (IgSF) that form a complex protein interaction network. DIP and Dpr proteins are expressed in a synaptic layer-specific fashion in the visual system. How interactions between these proteins regulate layer-specific synaptic circuitry is not known. Here we establish that DIP-α and its interacting partners Dpr6 and Dpr10 regulate multiple processes, including arborization within layers, synapse number, layer specificity, and cell survival. We demonstrate that heterophilic binding between Dpr6/10 and DIP-α and homophilic binding between DIP-α proteins promote interactions between processes in vivo. Knockin mutants disrupting the DIP/Dpr binding interface reveal a role for these proteins during normal development, while ectopic expression studies support an instructive role for interactions between DIPs and Dprs in circuit development. These studies support an important role for the DIP/Dpr protein interaction network in regulating cell-type-specific connectivity patterns.

A negative computed tomography may be sufficient to safely discharge patients with abdominal seatbelt sign from the emergency department: A case series analysis.

BACKGROUND: The presence of an abdominal seatbelt sign (ASBS) following a motor vehicle collision (MVC) is associated with a high risk for occult intra-abdominal injury, prompting imaging studies and a prolonged period of clinical observation. The aim of this study was to determine how a negative computed tomography (CT) of the abdomen/pelvis (A/P) can serve in the safe disposition of these patients. Our hypothesis was that in the setting of a negative CT, the presence of occult intra-abdominal injuries requiring a delayed intervention is extremely unlikely. METHODS: The medical charts of patients admitted from January 2014 to December 2016 to a Level I trauma center following an MVC were reviewed for a documentation of an ASBS. Patients who did not have a CT A/P upon admission were excluded. The CT A/P of the remaining patients were then classified as negative if there were no findings of acute vascular, visceral or bony injury or positive if any of these findings was present. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of CT A/P for the presence of an intra-abdominal injury were calculated. RESULTS: Over the 3-year study period, 1,108 patients were admitted after an MVC. Of those, 196 (17.7%) had an ASBS upon presentation and 183 (93.4%) of 196 underwent a CT A/P. A total of 114 (62.3%) of 183 had a negative CT A/P. These patients remained hospitalized for a median of 2 (1-35) days with none (0.0%) requiring a delayed laparotomy. The sensitivity of CT A/P in identifying patients requiring an exploratory laparotomy was 100.0%, specificity was 67.9%, NPV was 100.0%, and PPV was 21.7%. The negative likelihood ratio was 0.00. CONCLUSION: For patients with an ASBS following an MVC, a negative CT A/P may be sufficient for safe discharge from the emergency department without any need for additional clinical observation. LEVEL OF EVIDENCE: Therapuetic, level IV.

Nonoperative Management of Blunt Splenic Trauma in Patients with Traumatic Brain Injury: Feasibility and Outcomes.

INTRODUCTION: Preventing secondary insult to the brain is imperative following traumatic brain injury (TBI). Although TBI does not preclude nonoperative management (NOM) of splenic injuries, development of hypotension in this setting may be detrimental and could therefore lead trauma surgeons to a lower threshold for operative intervention and a potentially higher risk of failure of NOM (FNOM). We hypothesized that the presence of a TBI in patients with blunt splenic injury would lead to a higher risk of FNOM. METHODS: Patients with blunt splenic injury were selected from the National Trauma Data Bank research datasets from 2007 to 2011. TBI was defined as AIS head ≥ 3 and FNOM as patients who underwent a spleen-related operation after 2 h from admission. TBI patients were compared to those without head injury. The primary outcome was FNOM. RESULTS: Of 47,713 patients identified, 41,436 (86.8%) underwent a trial of NOM. FNOM was identical (10.6 vs. 10.8%, p = 0.601) among patients with and without TBI. TBI patients had lower adjusted odds for FNOM (AOR 0.66, p < 0.001), even among those with a high-grade splenic injury (AOR 0.68, p < 0.001). No difference in adjusted mortality was noted when comparing TBI patients with and without FNOM (AOR 1.01, p = 0.95). CONCLUSIONS: NOM of blunt splenic trauma in TBI patients has higher adjusted odds for success. This could be related to interventions targeting prevention of secondary brain injury. Further studies are required to identify those specific practices that lead to a higher success rate of NOM of splenic trauma in TBI patients.

Helicopter Transport Use for Trauma Patients Is Decreasing Significantly Nationwide but Remains Overutilized.

Rapid transfer of trauma patients to a trauma center for definitive management is essential to increase survival. The utilization of helicopter transportation for this purpose remains heavily debated. The purpose of this study was to characterize the trends in helicopter transportations of trauma patients in the United States over the last decade. Subjects with a primary mode of either ground or helicopter transportation were selected from the National Trauma Data Bank datasets 2007 to 2015. Over this period, the proportion of patients transported by a helicopter decreased significantly in a linear fashion from 17 per cent in 2007 to 10.2 per cent in 2015 (P < 0.001). The overall mortality of this population was 7.6 per cent and remained unchanged over the study period (P = 0.545). Almost 3 of 10 subjects (29.4%) transported by a helicopter had an Injury Severity Score <9. The proportion of elderly (>65 years) patients requiring helicopter transportation increased by 69.1 per cent, whereas their associated mortality decreased by 21.5 per cent. The use of a helicopter for the transportation of trauma patients has significantly decreased over the last decade without any significant change in mortality, possibly indicating more effective utilization of available resources. Overtriage of patients with minor injuries remained relatively unchanged.