Changing Landscape of Open Offers in Liver Transplantation in the Machine Perfusion Era: Exposure, Equity, and Economics.

BACKGROUND: Open offers (OOs) in liver transplantation (LT) result from bypassing the traditional allocation system. Little is known about the trends of OOs or the differences in donor/recipient characteristics compared to traditionally placed organs. We aim to quantify modern practices regarding OOs and understand NMP's impact, focusing on social determinants of health (SDH), cost, and graft-associated risk. METHODS: LTs from 1/1/2018 to 12/31/2023 at a single center were included. NMP was implemented on 10/1/2022. The CDC (centers for disease control)-validated social vulnerability index (SVI) and donor risk index (DRI) were calculated. Comprehensive complications index (CCI), Clavien-Dindo grades, patient and graft survival, and costs of transplantation were included. RESULTS: 1162 LTs were performed; 193 (16.8%) from OOs. OOs were more common in the post-NMP era (26.5% vs. 13.3%, p < 0.001). Pre-NMP, patients receiving OOs had longer waitlist times (118 vs. 69 days, p < 0.001), lower MELDs (17 vs. 25 points, p < 0.001), and riskier grafts (DRI = 1.8 vs. 1.6, p = 0.004) compared to standard offers. Post-NMP, recipients receiving OOs demonstrated no difference in waitlist time (27 vs. 20 days, p = 0.21) or graft risk (DRI = 2.03 vs. 2.23, p = 0.17). OO recipient MELD remained lower (16 vs. 22, p < 0.001). OO recipients were more socially vulnerable (SVI), pre-NMP (0.41 vs. 0.36, p = 0.004), but less vulnerable after NMP (0.23 vs. 0.36, p = 0.019). Despite increased graft risk, pre-NMP OO-LTs were less expensive in the 90-day global period ($154 939 vs. $178 970, p = 0.002) and the 180-days pre-/post-LT ($208 807 vs. $228 091, p = 0.021). Cost trends remained similar with NMP. CONCLUSION: OOs are increasingly utilized and may be appealing due to demonstrated cost reductions even with NMP. Although most OO-related metrics in our center remain similar before and after machine perfusion, programs should take caution that increasing use does not worsen organ access for socially vulnerable populations.

Valproic Acid Protects Against Acute Kidney Injury in Hemorrhage and Trauma.

INTRODUCTION: Trauma is the leading cause of death among young people. These patients have a high incidence of kidney injury, which independently increases the risk of mortality. As valproic acid (VPA) treatment has been shown to improve survival in animal models of lethal trauma, we hypothesized that it would also attenuate the degree of acute kidney injury. METHODS: We analyzed data from two separate experiments where swine were subjected to lethal insults.  Model 1: hemorrhage (50% blood volume hemorrhage followed by 72-h damage control resuscitation). Model 2: polytrauma (traumatic brain injury, 40% blood volume hemorrhage, femur fracture, rectus crush and grade V liver laceration). Animals were resuscitated with normal saline (NS) +/- VPA 150 mg/kg after a 1-h shock phase in both models (n = 5-6/group). Serum samples were analyzed for creatinine (Cr) using colorimetry on a Liasys 330 chemistry analyzer. Proteomic analysis was performed on kidney tissue sampled at the time of necropsy. RESULTS: VPA treatment significantly (P < 0.05) improved survival in both models. (Model 1: 80% vs 20%; Model 2: 83% vs. 17%). Model 1 (Hemorrhage alone): Cr increased from a baseline of 1.2 to 3.0 in NS control animals (P < 0.0001) 8 h after hemorrhage, whereas it rose only to 2.1 in VPA treated animals (P = 0.004). Model 2 (Polytrauma): Cr levels increased from baseline of 1.3 to 2.5 mg/dL (P = 0.01) in NS control animals 4 h after injury but rose to only 1.8 in VPA treated animals (P = 0.02). Proteomic analysis of kidney tissue identified metabolic pathways were most affected by VPA treatment. CONCLUSIONS: A single dose of VPA (150 mg/kg) offers significant protection against acute kidney injury in swine models of polytrauma and hemorrhagic shock.

Surgery Provider Perceptions on Telehealth Visits During the COVID-19 Pandemic: Room for Improvement.

BACKGROUND: COVID-19 has mandated rapid adoption of telehealth for surgical care. However, many surgical providers may be unfamiliar with telehealth. This study evaluates the perspectives of surgical providers practicing telehealth care during COVID-19 to help identify targets for surgical telehealth optimization. MATERIALS AND METHODS: At a single tertiary care center with telehealth capabilities, all department of surgery providers (attending surgeons, residents, fellows, and advanced practice providers) were emailed a voluntary survey focused on telehealth during the pandemic. Descriptive statistics and Mann-Whitney U analyses were performed as appropriate on responses. Text responses were thematically coded to identify key concepts. RESULTS: The completion rate was 41.3% (145/351). Providers reported increased telehealth usage relative to the pandemic (P < 0.001). Of respondents, 80% (116/145) had no formal telehealth training. Providers estimated that new patient video visits required less time than traditional visits (P = 0.001). Satisfaction was high for several aspects of video visits. Comparatively lower satisfaction scores were reported for the ability to perform physical exams (sensitive and nonsensitive) and to break bad news. The largest barriers to effective video visits were limited physical exams (55.6%; 45/81) and lack of provider or patient internet access/equipment/connection (34.6%; 28/81). Other barriers included ineffective communication and difficulty with fostering rapport. Concerns regarding video-to-telephone visit conversion were loss of physical exam/visual cues (34.3%; 24/70), less personal interactions (18.6%; 13/70), and reduced efficiency (18.6%; 13/70). CONCLUSIONS: Telehealth remains a new experience for surgical providers despite its expansion. Optimization strategies should target technology barriers and include specialized virtual exam and communication training.

Increased-risk donors and solid organ transplantation: current practices and opportunities for improvement.

PURPOSE OF REVIEW: The development and implementation of 'increased risk donor' (IRD) status by the Centers for Disease Control (CDC) was intended to guide patients and providers in decision making regarding risk of infectious transmission via solid organ transplantation. Several contemporary studies have shown underutilization of these organs. This review summarizes the issues surrounding IRD status as well as recent advances in our understanding of the risks and benefits of increased risk organs and their appropriate utilization. RECENT FINDINGS: Risk of window-period infection remains exceedingly low, and implementation of nucleic acid testing for HIV and hepatitis C virus (HCV) has resulted in decreasing risk of window-period infection often by an order of magnitude or more. Surgeons remain hesitant to utilize IRD organs. In addition, surgeon assessment of risk by donor behaviour was often discordant with known risks of those behaviours. Studies investigating outcomes of utilization of IRD organs suggest long-term mortality and graft survival is at least equivalent to non-IRD organs. Contemporary results suggest that IRD organs continue to be underutilized, particularly adult kidneys and lungs, with hundreds of wasted organs per year. SUMMARY: CDC IRD labelling has led to an underutilization of organs for transplantation. The risks associated with acceptance of an IRD organ are inflated by surgeons and patients, and outcomes for patients who undergo transplantation with increased risk organs are similar to or better than those for patients whom accept standard risk organs. The rate of transmission of window-period infection from IRD organs is exceptionally low. The harms regarding the utility of Public Health Service increased risk classification outweigh the benefits for patients in need of transplant.

Adapting to the Times: Combining Microlearning Videos and Twitter to Teach Surgical Technique.

OBJECTIVE: Surgical videos are commonly utilized by trainees to prepare for surgical cases. However, currently available videos tend to be of excessive length, variable quality, and exist behind paywalls or in other exclusive formats. Our objective was to create a series of videos that would address these shortcomings, and further allow for dynamic engagement between learners and experts. DESIGN: Our group created surgical videos using principles of microlearning, an educational strategy which deconstructs content into small units and uses social media platforms where learners and educators may actively engage. We published a library of short (<3 min) videos covering various steps of abdominal transplantation operations on a YouTube channel. We leveraged Twitter to disseminate the content and engage with experts and learners from around the world. SETTING: Multi-institutional. RESULTS: Over the period from July 2020 to January 2021, 24 microlearning videos were created, stored on a YouTube channel, and posted to Twitter weekly using a newly created account. During that time period, the videos, averaging 124 seconds in length, were viewed 4393 times and watched for a total of 127 hours. The account gained 611 followers in 37 countries and 37 US states with 312,400 impressions (defined as tweet views). Twitter users who engaged with our microlearning content (favorite, retweet, or reply) included faculty (27%), residents (21%), fellows (8%), and medical students (11%). CONCLUSIONS: Broad participation with the educational material and discussion on Twitter demonstrated the potential for the microlearning technique to provide educational benefit for learners internationally. The spread of the tweets shows an opportunity to augment traditional surgical education, and the willingness of faculty to discuss alternative techniques with their peers. Our group will continue to develop a library of microlearning videos for surgical operations and engage with other institutions for collaboration and expansion.

Prehospital end-tidal carbon dioxide is predictive of death and massive transfusion in injured patients: An Eastern Association for Surgery of Trauma multicenter trial.

BACKGROUND: Prehospital identification of the injured patient likely to require emergent care remains a challenge. End-tidal carbon dioxide (ETCO2) has been used in the prehospital setting to monitor respiratory physiology and confirmation of endotracheal tube placement. Low levels of ETCO2 have been demonstrated to correlate with injury severity and mortality in a number of in-hospital studies. We hypothesized that prehospital ETCO2 values would be predictive of mortality and need for massive transfusion (MT) in intubated patients. METHODS: This was a retrospective multicenter trial with 24 participating centers. Prehospital, emergency department, and hospital values were collected. Receiver operating characteristic curves were created and compared. Massive transfusion defined as >10 U of blood in 6 hours or death in 6 hours with at least 1 U of blood transfused. RESULTS: A total of 1,324 patients were enrolled. ETCO2 (area under the receiver operating characteristic curve [AUROC], 0.67; confidence interval [CI], 0.63-0.71) was better in predicting mortality than shock index (SI) (AUROC, 0.55; CI, 0.50-0.60) and systolic blood pressure (SBP) (AUROC, 0.58; CI, 0.53-0.62) (p < 0.0005). Prehospital lowest ETCO2 (AUROC, 0.69; CI, 0.64-0.75), SBP (AUROC, 0.75; CI, 0.70-0.81), and SI (AUROC, 0.74; CI, 0.68-0.79) were all predictive of MT. Analysis of patients with normotension demonstrated lowest prehospital ETCO2 (AUROC, 0.66; CI, 0.61-0.71), which was more predictive of mortality than SBP (AUROC, 0.52; CI, 0.47-0.58) or SI (AUROC, 0.56; CI, 0.50-0.62) (p < 0.001). Lowest prehospital ETCO2 (AUROC, 0.75; CI, 0.65-0.84), SBP (AUROC, 0.63; CI, 0.54-0.74), and SI (AUROC, 0.64; CI, 0.54-0.75) were predictive of MT in normotensive patients. ETCO2 cutoff for MT was 26 mm Hg. The positive predictive value was 16.1%, and negative predictive value was high at 98.1%. CONCLUSION: Prehospital ETCO2 is predictive of mortality and MT. ETCO2 outperformed traditional measures such as SBP and SI in the prediction of mortality. ETCO2 may outperform traditional measures in predicting need for transfusion in occult shock. LEVEL OF EVIDENCE: Diagnostic test, level III.

Population-based Trends in Obesity and Kidney Transplantation Among Patients With End-stage Kidney Disease.

Obesity is a barrier to transplant, reducing access and leading to worse outcomes versus nonobese adults. Most transplant centers in the United States maintain body mass index (BMI) cutoffs to listing for kidney transplantation of 35 to 40 kg/m2. There is little contemporary data on the prevalence of obesity among patients with end-stage kidney disease (ESKD) despite its impact on clinical outcomes and healthcare expenditures. METHODS: We utilized data from the US Renal Data System from 2008 to 2016 to identify a prevalent cohort of 1 079 410 patients with ESKD. Linear regression determined trends in the proportion of patients within each category of BMI. We also evaluated geographic variation in rates of obesity and transplantation across the United States. RESULTS: Among the 1 079 410 ESKD patients, the largest cohort of patients were those with obesity (n = 423 270; 39.2%). There were 309 707 (28.7%) patients with an overweight BMI and 274 683 (25.4%) with a normal BMI. The proportion of patients with obesity increased significantly from 36.8% in 2008 to 40.2% in 2016 (trend 0.28; 95% confidence interval, 0.05-0.51). There was significant geographic variation by state with rates of obesity ranging from 32.3% to 45.4% and state transplant rates among those obese patients ranging from 22.5% to 46.8%. There is a weak correlation between states with increased rates of obese ESKD patients and states with an increased obesity transplant rate as indicated with r = 0.40 (P = 0.003). CONCLUSIONS: Beneficiaries with obesity are now the largest and fastest growing demographic among patients with ESKD in the United States.

Brain proteomic changes by histone deacetylase inhibition after traumatic brain injury.

BACKGROUND: Traumatic brain injury (TBI) is a leading cause of morbidity and mortality. There are currently no cytoprotective treatments for TBI. There is growing evidence that the histone deacetylase inhibitor valproic acid (VPA) may be beneficial in the treatment of TBI associated with hemorrhagic shock and in isolation. We sought to further evaluate the mechanistic underpinnings of this demonstrated efficacy via proteomic analysis of injured brain tissue. METHODS: Swine were subjected to TBI via controlled cortical impact, randomized to treatment with VPA or control and observed for 6 hours. The brains of the pigs were then sectioned, and tissue was prepared and analyzed for proteomic data, including gene ontology (GO), gene-set enrichment analysis and enrichment mapping, and network mapping. RESULTS: Proteomic analysis demonstrated differential expression of hundreds of proteins in injured brain tissue after treatment with VPA. GO analysis and network analyses revealed groups of proteins and processes that are known to modulate injury response after TBI and impact cell fate. Processes affected included protein targeting and transport, cation and G-protein signaling, metabolic response, neurotransmitter response and immune function. DISCUSSION: This proteomic analysis provides initial mechanistic insight into the observed rescue of injured brain tissue after VPA administration in isolated TBI. LEVEL OF EVIDENCE: Not applicable (animal study).

Validation of intraosseous delivery of valproic acid in a swine model of polytrauma.

BACKGROUND: Intraosseous (IO) drug delivery may be necessary in emergency situations when intravenous access is unattainable. Valproic acid (VPA) is a histone deacetylase inhibitor that has previously been shown to improve survival in preclinical models of lethal polytrauma. In this study, we sought to compare serum levels of intravenously and IO-delivered VPA, and to analyze the effect of IO-delivered VPA. METHODS: Swine were subjected to 40% blood volume hemorrhage, brain injury, femur fracture, rectus crush injury and liver laceration. After 1 hour of shock, animals were randomized (n=3/group) to receive normal saline resuscitation (control), normal saline+intravenous VPA 150 mg/kg (intravenous group) or normal saline +IO VPA 150 mg/kg (IO group). Serum levels of VPA were assessed between groups, and proteomics analyses were performed on IO and control groups on heart, lung and liver samples. RESULTS: Intravenous and IO serum VPA levels were similar at 1, 3, 5 and 7 hours after starting the infusion (p>0.05). IO-delivered VPA induced significant proteomics changes in the heart, lung and liver, which were most pronounced in the lung. Biologic processes affected included inflammation, metabolism and transcriptional & translational machinery. The control group had 0% survival, and the intravenous and IO group both had 100% survival to the end of the experiment (p<0.05). DISCUSSION: IO-delivered VPA is noninferior to intravenous administration and is a viable option in emergent situations when intravenous access is unattainable. LEVEL OF EVIDENCE: Not applicable (animal study).

Assessment of Potentially Preventable Hospital Readmissions After Major Surgery and Association With Public vs Private Health Insurance and Comorbidities.

Importance: Rehospitalization after major surgery is common and represents a significant cost to the health care system. Little is known regarding the causes of these readmissions and the degree to which they may be preventable. Objective: To evaluate the degree to which readmissions after major surgery are potentially preventable. Design, Setting, and Participants: This retrospective cohort study used a weighted sample of 1 937 354 patients from the 2017 National Readmissions Database to evaluate all adult inpatient hospitalizations for 1 of 7 common major surgical procedures. Statistical analysis was performed from January 14 to November 30, 2020. Main Outcomes and Measures: The study calculated 90-day readmission rates as well as rates of readmissions that were considered potentially preventable. Potentially preventable readmissions (PPRs) were defined as those with a primary diagnosis code for superficial surgical site infection, acute kidney injury, aspiration pneumonitis, or any of the Agency for Healthcare Research and Quality-defined ambulatory care sensitive conditions. Multivariable logistic regression was used to identify factors associated with PPRs. Results: A total weighted sample of 1 937 354 patients (1 048 046 women [54.1%]; mean age, 66.1 years [95% CI, 66.0-66.3 years]) underwent surgical procedures; 164 755 (8.5%) experienced a readmission within 90 days. Potentially preventable readmissions accounted for 29 321 (17.8%) of all 90-day readmissions, for an estimated total cost to the US health care system of approximately $296 million. The most common reasons for PPRs were congestive heart failure exacerbation (34.6%), pneumonia (12.0%), and acute kidney injury (22.5%). In a multivariable model of adults aged 18 to 64 years, patients with public health insurance (Medicare or Medicaid) had more than twice the odds of PPR compared with those with private insurance (adjusted odds ratio, 2.09; 95% CI, 1.94-2.25). Among patients aged 65 years or older, patients with private insured had 18% lower odds of PPR compared with patients with Medicare as the primary payer (adjusted odds ratio, 0.82; 95% CI, 0.74-0.90). Conclusions and Relevance: This study suggests that nearly 1 in 5 readmissions after surgery are potentially preventable and account for nearly $300 million in costs. In addition to better inpatient care, improved access to ambulatory care may represent an opportunity to reduce costly readmissions among surgical patients.

A single dose of valproic acid improves neurologic recovery and decreases brain lesion size in swine subjected to an isolated traumatic brain injury.

BACKGROUND: We lack specific treatments for traumatic brain injury (TBI), which remains the leading cause of trauma-related morbidity and mortality. Treatment with valproic acid (VPA) improves outcomes in models of severe TBI with concurrent hemorrhage. However, it is unknown if VPA will have similar benefits after isolated nonlethal TBI, which is the more common clinical scenario. The goal of this study was to evaluate the effect of VPA treatment in a preclinical isolated TBI swine model on neurologic outcomes and brain lesion size and to perform detailed pharmacokinetic analyses for a future clinical trial. METHODS: Yorkshire swine (n = 10; 5/cohort) were subjected to TBI (8-mm controlled cortical impact). An hour later, we randomized them to receive VPA (150 mg/kg) or saline placebo (control). Neuroseverity scores were assessed daily (0 [normal] to 36 [comatose]), brain lesion size was measured on postinjury 3, and serial blood samples were collected for pharmacokinetic studies. RESULTS: Physiologic parameters and laboratory values were similar in both groups. Valproic acid-treated animals demonstrated significantly better neuroseverity scores on postinjury 1 (control, 9.2 ± 4.4; VPA, 0 ± 0; p = 0.001). Valproic acid-treated animals had significantly smaller brain lesion sizes (mean volume in microliter: control, 3,130 ± 2,166; VPA, 764 ± 208; p = 0.02). Pharmacokinetic data confirmed adequate plasma and tissue levels of VPA. CONCLUSION: In this clinically relevant model of isolated TBI, a single dose of VPA attenuates neurological impairment and decreases brain lesion size.

A novel partial resuscitative endovascular balloon aortic occlusion device that can be deployed in zone 1 for more than 2 hours with minimal provider titration.

BACKGROUND: Hemorrhage is a leading cause of mortality in trauma. Resuscitative endovascular balloon occlusion of the aorta (REBOA) can control hemorrhage, but distal ischemia, subsequent reperfusion injury, and the need for frequent balloon titration remain problems. Improved device design can allow for partial REBOA (pREBOA) that may provide hemorrhage control while also perfusing distally without need for significant provider titration. METHODS: Female Yorkshire swine (N = 10) were subjected to 40% hemorrhagic shock for 1 hour (mean arterial pressure [MAP], 28-32 mm Hg). Animals were then randomized to either complete aortic occlusion (ER-REBOA) or partial occlusion (novel pREBOA-PRO) without frequent provider titration or distal MAP targets. Detection of a trace distal waveform determined partial occlusion in the pREBOA-PRO arm. After 2 hours of zone 1 occlusion, the hemorrhaged whole blood was returned. After 50% autotransfusion, the balloon was deflated over a 10-minute period. Following transfusion, the animals were survived for 2 hours while receiving resuscitation based on objective targets: lactated Ringer's fluid boluses (goal central venous pressure, ≥ 6 mm Hg), a norepinephrine infusion (goal MAP, 55-60 mm Hg), and acid-base correction (goal pH, >7.2). Hemodynamic variables, arterial lactate, lactate dehydrogenase, aspartate aminotransferase, and creatinine levels were measured. RESULTS: All animals survived throughout the experiment, with similar increase in proximal MAPs in both groups. Animals that underwent partial occlusion had slightly higher distal MAPs. At the end of the experiment, the partial occlusion group had lower end levels of serum lactate (p = 0.006), lactate dehydrogenase (p = 0.0004) and aspartate aminotransferase (p = 0.004). Animals that underwent partial occlusion required less norepinephrine (p = 0.002), less bicarbonate administration (p = 0.006), and less fluid resuscitation (p = 0.042). CONCLUSION: Improved design for pREBOA can decrease the degree of distal ischemia and reperfusion injury compared with complete aortic occlusion, while providing a similar increase in proximal MAPs. This can allow pREBOA zone-1 deployment for longer periods without the need for significant balloon titration.

Development of a large animal model of lethal polytrauma and intra-abdominal sepsis with bacteremia.

BACKGROUND: Trauma and sepsis are individually two of the leading causes of death worldwide. When combined, the mortality is greater than 50%. Thus, it is imperative to have a reproducible and reliable animal model to study the effects of polytrauma and sepsis and test novel treatment options. Porcine models are more translatable to humans than rodent models due to the similarities in anatomy and physiological response. We embarked on a study to develop a reproducible model of lethal polytrauma and intra-abdominal sepsis, which was lethal, though potentially salvageable with treatment. METHODS: Our laboratory has a well-established porcine model that was used as the foundation. Animals were subjected to a rectus crush injury, long bone fracture, liver and spleen laceration, traumatic brain injury and hemorrhage that was used as a foundation. We tested various colon injuries to create intra-abdominal sepsis. All animals underwent injuries followed by a period of shock, then subsequent resuscitation. RESULTS: All animals had blood culture-proven sepsis. Attempts at long-term survival of animals after injury were ceased because of poor appetite and energy. We shifted to an 8-hour endpoint. The polytrauma injury pattern remained constant and the colon injury pattern changed with the intention of creating a model that was ultimately lethal but potentially salvageable with a therapeutic drug. An uncontrolled cecal injury (n=4) group resulted in very early deaths. A controlled cecal injury (CCI; n=4) group had prolonged time prior to mortality with one surviving to the endpoint. The sigmoid injury (n=5) produced a similar survival curve to CCI but no animals surviving to the endpoint. CONCLUSION: We have described a porcine model of polytrauma and sepsis that is reproducible and may be used to investigate novel treatments for trauma and sepsis. LEVEL OF EVIDENCE: Not applicable. Animal study.

Fostering Passion and Skills in Surgical Research Across the Medical Education Continuum: The Transplant Research, Education, and Engagement Group.

OBJECTIVE: We describe a multilevel, collaborative research group for trainees and faculty engaging in transplant surgery research within one institution. DESIGN: Transplant Research, Education, and Engagement (TREE) was designed to develop trainees' research skills and foster enthusiasm in transplant surgery along the educational continuum. Our research model intentionally empowers junior researchers, including undergraduates and medical students, to assume active roles on a range of research projects and contribute new ideas within a welcoming research and learning environment. SETTING: Section of Transplant Surgery, Department of Surgery, Michigan Medicine, Ann Arbor, Michigan. PARTICIPANTS: Undergraduate premedical students, first through fourth year medical students, general surgery residents, transplant surgery fellows, and transplant surgery faculty. RESULTS: TREE was founded in September 2019 and has grown to include over 30 active members who meet weekly and collaborate virtually on a range of research projects, many of which are led by students. Trainees can assume both mentee and mentor roles and build their research, presentation and writing skills while collaborating academically. CONCLUSIONS: Our model has increased trainees' engagement in transplant research projects and fosters early enthusiasm for the field. This model can be feasibly replicated at other institutions and within other subspecialties.

Administration of valproic acid in clinically approved dose improves neurologic recovery and decreases brain lesion size in swine subjected to hemorrhagic shock and traumatic brain injury.

BACKGROUND: Traumatic brain injury (TBI) and hemorrhage remain the leading causes of death after trauma. We have previously shown that a dose of valproic acid (VPA) at (150 mg/kg) can decrease brain lesion size and hasten neurologic recovery. The current Food and Drug Administration-approved dose of VPA is 60 mg/kg. We evaluate neurologic outcomes and brain lesion size of a single dose of VPA at a level currently within Food and Drug Administration-approved dose in swine subjected to TBI and hemorrhagic shock. METHODS: Swine (n = 5/group) were subjected to TBI and 40% blood volume hemorrhage. Animals remained in shock for 2 hours before randomization to normal saline (NS) resuscitation alone (control), NS-VPA 150 mg/kg (VPA 150), or NS-VPA 50 mg/kg (VPA 50). Neurologic severity scores (range, 0-32) were assessed daily for 14 days, and brain lesion size was measured via magnetic resonance imaging on postinjury day (PID) 3. RESULTS: Shock severity and laboratory values were similar in all groups. Valproic acid-treated animals demonstrated significantly less neurologic impairment on PID 1 and returned to baseline faster (PID 1 mean neurologic severity score, control = 22 ± 3 vs. VPA 150 mg/kg = 8 ± 7 or VPA 50 mg/kg = 6 ± 6; p = 0.02 and 0.003). Valproic acid-treated animals had significantly smaller brain lesion sizes (mean volume in mm3, control = 1,268.0 ± 241.2 vs. VPA 150 mg/kg = 620.4 ± 328.0 or VPA 50 mg/kg = 438.6 ± 234.8; p = 0.007 and 0.001). CONCLUSION: In swine subjected to TBI and hemorrhagic shock, VPA treatment, in a dose that is approved for clinical use, decreases brain lesion size and reduces neurologic impairment compared with resuscitation alone.