Multifaceted Benefit of Whole Blood Versus Lactated Ringer's Resuscitation After Traumatic Brain Injury and Hemorrhagic Shock in Mice

Association Between Whole Blood Transfusion and Mortality Among Patients With Hemorrhagic Shock and Traumatic Brain Injury

BACKGROUND AND OBJECTIVES

Whole blood (WB) transfusion in trauma has been revisited, and recent studies have reported an association between WB and improved survival among patients with hemorrhagic shock. However, no evidence of a similar association exists for patients with hemorrhagic shock and traumatic brain injury (TBI). This study aimed to assess the association between WB and mortality among patients with hemorrhagic shock and TBI.

METHODS

This study retrospectively analyzed data obtained from American College of Surgeons-Trauma Quality Improvement Program during January 2020 to December 2021. Patients (age ≥18 years) requiring blood transfusion within 4 hours of hospital arrival and sustaining TBI (head Abbreviated Injury Scale >2) were included. Survival at 30 days were compared after performing 1:1 propensity score matching for demographics, injury type, vital signs on admission, TBI characteristics, injury characteristics, comorbidities, hemorrhage control procedures, hospital characteristics, and withdrawal of life support.

RESULTS

A total of 15 967 patients were eligible for analysis. The median age was 42 years (interquartile range: 28-60 years); 11 789 (73.8%) patients were male, and 10 102 (63.2%) patients were White. Of them, 2725 (17.0%) received WB. After a 1:1 propensity score matching, 2720 matched pairs were compared. Matched patients had 1.0 as median shock index and 79 mm Hg as the lowest systolic blood pressure requiring immediate transfusion. WB was not associated with reduced 30-day mortality, compared with non-WB (34.0% vs 34.7%, odds ratio: 0.97, 95% confidence interval: 0.87-1.09).

CONCLUSION

WB was not associated with reduced 30-day mortality among patients with hemorrhagic shock and TBI. These findings suggest that not all patients with hemorrhagic shock would benefit from WB.

THE NEUROENDOTHELIAL AXIS IN TRAUMATIC BRAIN INJURY: MECHANISMS OF MULTIORGAN DYSFUNCTION, NOVEL THERAPIES, AND FUTURE DIRECTIONS

ABSTRACT

Severe traumatic brain injury (TBI) often initiates a systemic inflammatory response syndrome, which can potentially culminate into multiorgan dysfunction. A central player in this cascade is endotheliopathy, caused by perturbations in homeostatic mechanisms governed by endothelial cells due to injury-induced coagulopathy, heightened sympathoadrenal response, complement activation, and proinflammatory cytokine release. Unique to TBI is the potential disruption of the blood-brain barrier, which may expose neuronal antigens to the peripheral immune system and permit neuroinflammatory mediators to enter systemic circulation, propagating endotheliopathy systemically. This review aims to provide comprehensive insights into the "neuroendothelial axis" underlying endothelial dysfunction after TBI, identify potential diagnostic and prognostic biomarkers, and explore therapeutic strategies targeting these interactions, with the ultimate goal of improving patient outcomes after severe TBI.

Crystalloid volume is associated with short-term morbidity in children with severe traumatic brain injury: An Eastern Association for the Surgery of Trauma multicenter trial post hoc analysis

OBJECTIVE

This study examined differences in clinical and resuscitation characteristics between injured children with and without severe traumatic brain injury (sTBI) and aimed to identify resuscitation characteristics associated with improved outcomes following sTBI.

METHODS

This is a post hoc analysis of a prospective observational study of injured children younger than 18 years (2018-2019) transported from the scene, with elevated shock index pediatric-adjusted on arrival and head Abbreviated Injury Scale score of ≥3. Timing and volume of resuscitation products were assessed using χ 2t test, Fisher's exact t test, Kruskal-Wallis, and multivariable logistic regression analyses.

RESULTS

There were 142 patients with sTBI and 547 with non-sTBI injuries. Severe traumatic brain injury patients had lower initial hemoglobin (11.3 vs. 12.4, p < 0.001), greater initial international normalized ratio (1.4 vs. 1.1, p < 0.001), greater Injury Severity Score (25 vs. 5, p < 0.001), greater rates of ventilator (59% vs. 11%, p < 0.001) and intensive care unit (ICU) requirement (79% vs. 27%, p < 0.001), and more inpatient complications (18% vs. 3.3%, p < 0.001). Severe traumatic brain injury patients received more prehospital crystalloid (25% vs. 15%, p = 0.008), ≥1 crystalloid boluses (52% vs. 24%, p < 0.001), and blood transfusion (44% vs. 12%, p < 0.001) than non-sTBI patients. Among sTBI patients, receipt of ≥1 crystalloid bolus (n = 75) was associated with greater ICU need (92% vs. 64%, p < 0.001), longer median ICU (6 vs. 4 days, p = 0.027) and hospital stay (9 vs. 4 days, p < 0.001), and more in-hospital complications (31% vs. 7.5%, p = 0.003) than those who received <1 bolus (n = 67). These findings persisted after adjustment for Injury Severity Score (odds ratio, 3.4-4.4; all p < 0.010).

CONCLUSION

Pediatric trauma patients with sTBI received more crystalloid than those without sTBI despite having a greater international normalized ratio at presentation and more frequently requiring blood products. Excessive crystalloid may be associated with worsened outcomes, including in-hospital mortality, seen among pediatric sTBI patients who received ≥1 crystalloid bolus. Further attention to a crystalloid sparing, early transfusion approach to resuscitation of children with sTBI is needed.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level IV.

Controversies and evidence gaps in the early management of severe traumatic brain injury: back to the ABCs

Traumatic brain injury (TBI) accounts for around 30% of all trauma-related deaths. Over the past 40 years, TBI has remained a major cause of mortality after trauma. The primary injury caused by the injurious mechanical force leads to irreversible damage to brain tissue. The potentially preventable secondary injury can be accentuated by addressing systemic insults. Early recognition and prompt intervention are integral to achieve better outcomes. Consequently, surgeons still need to be aware of the basic yet integral emergency management strategies for severe TBI (sTBI). In this narrative review, we outlined some of the controversies in the early care of sTBI that have not been settled by the publication of the Brain Trauma Foundation’s 4th edition guidelines in 2017. The topics covered included the following: mode of prehospital transport, maintaining airway patency while securing the cervical spine, achieving adequate ventilation, and optimizing circulatory physiology. We discuss fluid resuscitation and blood product transfusion as components of improving circulatory mechanics and oxygen delivery to injured brain tissue. An outline of evidence-based antiplatelet and anticoagulant reversal strategies is discussed in the review. In addition, the current evidence as well as the evidence gaps for using tranexamic acid in sTBI are briefly reviewed. A brief note on the controversial emergency surgical interventions for sTBI is included. Clinicians should be aware of the latest evidence for sTBI. Periods between different editions of guidelines can have an abundance of new literature that can influence patient care. The recent advances included in this review should be considered both for formulating future guidelines for the management of sTBI and for designing future clinical studies in domains with clinical equipoise.

Choice of Whole Blood versus Lactated Ringer's Resuscitation Modifies the Relationship between Blood Pressure Target and Functional Outcome after Traumatic Brain Injury plus Hemorrhagic Shock in Mice

Civilian traumatic brain injury (TBI) guidelines recommend resuscitation of patients with hypotensive TBI with crystalloids. Increasing evidence, however, suggests that whole blood (WB) resuscitation may improve physiological and survival outcomes at lower resuscitation volumes, and potentially at a lower mean arterial blood pressure (MAP), than crystalloid after TBI and hemorrhagic shock (HS). The objective of this study was to assess whether WB resuscitation with two different MAP targets improved behavioral and histological outcomes compared with lactated Ringer's (LR) in a mouse model of TBI+HS. Anesthetized mice (n = 40) underwent controlled cortical impact (CCI) followed by HS (MAP = 25-27 mm Hg; 25 min) and were randomized to five groups for a 90 min resuscitation: LR with MAP target of 70 mm Hg (LR70), LR60, WB70, WB60, and monitored sham. Mice received a 20 mL/kg bolus of LR or autologous WB followed by LR boluses (10 mL/kg) every 5 min for MAP below target. Shed blood was reinfused after 90 min. Morris Water Maze testing was performed on days 14-20 post-injury. Mice were euthanized (21 d) to assess contusion and total brain volumes. Latency to find the hidden platform was greater versus sham for LR60 (p < 0.002) and WB70 (p < 0.007) but not LR70 or WB60. The WB resuscitation did not reduce contusion volume or brain tissue loss. The WB targeting a MAP of 60 mm Hg did not compromise function versus a 70 mm Hg target after CCI+HS, but further reduced fluid requirements (p < 0.03). Using LR, higher achieved MAP was associated with better behavioral performance (rho = -0.67, p = 0.028). Use of WB may allow lower MAP targets without compromising functional outcome, which could facilitate pre-hospital TBI resuscitation.