Volume and electrolyte management

Goal-directed Fluid Therapy in Neurosurgery: Three Feet from Gold?

How to cite this article: Kothekar AT, Mohanty R, Joshi AV. Goal-directed Fluid Therapy in Neurosurgery: Three Feet from Gold? Indian J Crit Care Med 2023;27(10):697-698.

Fluid Resuscitation in Patients With Traumatic Brain Injury: A Comprehensive Review

Patients with traumatic brain injury (TBI) or head trauma present challenges for emergency physicians and neurosurgeons. Traumatic brain injury is currently a community health issue. For the best possible care, it is crucial to understand the various helpful therapy techniques in the pre-operative and pre-hospital phases. The initial rapid infusion of large volumes of mannitol and a hypertonic crystalloid solution to restore blood pressure and blood volume is the current standard of care for people with combined hemorrhagic shock (HS) and traumatic brain injury. The selection and administration of fluids to trauma and traumatic brain injury patients may be especially helpful in preventing subsequent ischemic brain damage because of the hemodynamic stabilizing effects of these fluids in hypovolemic shock. Traumatic brain injury is an essential factor that may lead to disability and death in a patient. Traumatic brain damage can develop either as a direct result of the trauma or as a result of the initial harm. Significant neurologic problems, such as cranial nerve damage, dementia, seizures, and Alzheimer's disease, can develop after a traumatic brain injury. The comorbidity of the victims may also be significantly increased by additional psychiatric problems such as psychological diseases and other behavioral and cognitive sequels. We review the history of modern fluid therapy, complications after traumatic brain injury, and the use of fluid treatment for decompressive craniectomy and traumatic brain injury.

Fluid therapy and traumatic brain injury: A narrative review

Traumatic brain injury (TBI) is an important health and social problem. The mechanism of damage of this entity could be divided into two phases: (1) a primary acute injury because of the traumatic event; and (2) a secondary injury due to the hypotension and hypoxia generated by the previous lesion, which leads to ischemia and necrosis of neural cells. Cerebral edema is one of the most important prognosis markers observed in TBI. In the early stages of TBI, the cerebrospinal fluid compensates the cerebral edema. However, if edema increases, this mechanism fails, increasing intracranial pressure. To avoid this chain effect, several treatments are applied in the clinical practice, including elevation of the head of the bed, maintenance of normothermia, pain and sedation drugs, mechanical ventilation, neuromuscular blockade, controlled hyperventilation, and fluid therapy (FT). The goal of FT is to improve the circulatory system to avoid the lack of oxygen to organs. Therefore, rapid and early infusion of large volumes of crystalloids is performed in clinical practice to restore blood volume and blood pressure. Despite the relevance of FT in the early management of TBI, there are few clinical trials regarding which solution is better to apply. The aim of this study is to provide a narrative review about the role of the different types of FT used in the daily clinical practice on the management of TBI. To achieve this objective, a physiopathological approach to this entity will be also performed, summarizing why the different types of FT are used.

Efficacy and Safety of Isotonic and Hypotonic Intravenous Maintenance Fluids in Hospitalised Children: A Systematic Review and Meta-Analysis of Randomised Controlled Trials

Hyponatraemia is a known complication in hospitalised children receiving maintenance intravenous fluid. Several studies have been published to investigate the efficacy and safety of intravenous fluids in children. However, there is still an ongoing debate regarding the ideal solution to be used in the paediatric population. Therefore, the aim of this meta-analysis was to investigate the safety and efficacy of administering isotonic versus hypotonic intravenous maintenance fluid in hospitalised children. An extensive search was undertaken on PubMed, Web of Science, Scopus, ScienceDirect, Google Scholar and Cochrane Library on 28 December 2020. Only randomised controlled trials (RCTs) were included. We used the random-effects model for all analyses. Risk ratio (RR) and mean difference with 95% confidence intervals (CIs) were used for dichotomous and continuous outcomes, respectively. The quality of each study was assessed using the Joanna Briggs Institute critical appraisal tool for RCTs. This study is registered with PROSPERO (CRD42021229067). Twenty-two RCTs with a total of 3795 participants were included. The studies encompassed surgical and medical patients admitted to intensive care unit as well as to general wards. We found that hypotonic fluid significantly increases the risk of hyponatremia at both ≤24 h (RR 0.34; 95% CI: 0.26–0.43, p < 0.00001) and >24 h (RR 0.48; 95% CI: 0.36–0.64, p < 0.00001). Isotonic fluid increases the risk of hypernatraemia at ≤24 h (RR 2.15; 95% CI: 1.24–3.73, p = 0.006). The prevalence of hyponatraemia was also higher in the hypotonic group at both ≤24 h (5.7% vs. 23.3%) and >24 h (6.0% vs. 26.3%). There was no statistically significant difference in the risk of developing adverse outcomes between the two groups. Mean serum and urine sodium as well as serum osmolality/osmolarity was lower in the hypotonic group. Isotonic solution is protective against the development of hyponatraemia while hypotonic solution increases the risk of hyponatraemia.

Fluid management in patients undergoing neurosurgery

Fluid management is an important component of perioperative care for patients undergoing neurosurgery. The primary goal of fluid management in neurosurgery is the maintenance of normovolemia and prevention of serum osmolarity reduction. To maintain normovolemia, it is important to administer fluids in appropriate amounts following appropriate methods, and to prevent a decrease in serum osmolarity, the choice of fluid is essential. There is considerable debate about the choice and optimal amounts of fluids administered in the perioperative period. However, there is little high-quality clinical research on fluid therapy for patients undergoing neurosurgery. This review will discuss the choice and optimal amounts of fluids in neurosurgical patients based on the literature, recent issues, and perioperative fluid management practices.

The Effect of Fluid Loading and Hypertonic Saline Solution on Cortical Cerebral Microcirculation and Glycocalyx Integrity

BACKGROUND

Fluid loading and hyperosmolar solutions can modify the cortical brain microcirculation and the endothelial glycocalyx (EG). This study compared the short-term effects of liberal fluid loading with a restrictive fluid intake followed by osmotherapy with hypertonic saline (HTS) on cerebral cortical microcirculation and EG integrity in a rabbit craniotomy model.

METHODS

The experimental rabbits were allocated randomly to receive either <2 mL/kg/h (group R, n=14) or 30 mL/kg/h (group L, n=14) of balanced isotonic fluids for 1 hour. Then, the animals were randomized to receive 5 mL/kg intravenous infusion of either 3.2% saline (group HTS, n=14) or 0.9% saline (group normal saline, n=13) in a 20-minute infusion. Microcirculation in the cerebral cortex based on sidestream dark-field imaging, a morphologic index of glycocalyx damage to sublingual and cortical brain microcirculation (the perfused boundary region), and serum syndecan-1 levels were evaluated.

RESULTS

Lower cortical brain perfused small vessel density (P=0.0178), perfused vessel density (P=0.0286), and total vessel density (P=0.0447) were observed in group L, compared with group R. No differences were observed between the HTS and normal saline groups after osmotherapy. Cerebral perfused boundary region values (P=0.0692) and hematocrit-corrected serum syndecan-1 levels (P=0.0324) tended to be higher in group L than in group R animals.

CONCLUSIONS

Liberal fluid loading was associated with altered cortical cerebral microcirculation and EG integrity parameters. The 3.2% saline treatment did not affect cortical cerebral microcirculation or EG integrity markers.

Y-Site Compatibility of Intravenous Levetiracetam With Commonly Used Critical Care Medications

Purpose: Levetiracetam is an antiepileptic medication commonly used in critical care areas for seizure treatment or prophylaxis. Compatibility data of levetiracetam with other critical care medications are limited, which can make administration challenging. This study aims to assess the physical Y-site compatibility of intravenous levetiracetam with some other commonly used critical care medications. Methods: Y-site administration was simulated by independently mixing levetiracetam with each of 11 selected medications in a 4-dram, colorless, screw-cap, glass vial, at a 1:1 ratio. Clinically used concentrations of each medication were compounded in 0.9% sodium chloride following United States Pharmacopeia chapter 797 standards. Physical compatibility was observed and assessed at 0, 15, and 30 minutes after mixing. Medication mixtures were considered physically incompatible if there was visual evidence of color change, gas evolution, haze, or particulate formation, pH change >10%, or if they had an absorbance value >0.010 A. Results: No evidence of physical incompatibility was observed during simulated Y-site testing with cisatracurium 1 mg/mL, dexmedetomidine 4 µg/mL, fosphenytoin 15 mg PE/mL, norepinephrine 16 mg/mL, norepinephrine 32 mg/mL, norepinephrine 64 mg/mL, piperacillin-tazobactam 33.75 mg/mL, propofol 10 mg/mL, vancomycin 5 mg/mL, or vasopressin 1 unit/mL when tested in 0.9% sodium chloride. Levetiracetam was incompatible with piperacillin-tazobactam 45 mg/mL. Conclusion: Levetiracetam 5 mg/mL in 0.9% sodium chloride was found to be physically compatible for 30 minutes with 10 of the 11 medications tested during simulated Y-site administration.

A prospective, randomized, double blind study to compare the effects of equiosmolar solutions of 3% hypertonic saline and 20% mannitol on reduction of brain-bulk during elective craniotomy for supratentorial brain tumor resection

Aims:

The aim of the study was to compare the effect of mannitol (M) and hypertonic saline (HTS) on brain relaxation and electrolyte balance.

Settings and Design:

Prospective, randomized, double-blind study.

Subjects and Methods:

A total of 114 patients with American Society of Anesthesiologists status II and III, scheduled to undergo craniotomy for supratentorial brain tumor resection were enrolled. Patients received 5 ml/kg 20% mannitol (n = 56) or 3% HTS (n = 58) at the start of scalp incision. Hemodynamics, fluid balance and electrolytes, were measured at 0, 15, 30, and 60 min and 6 h after infusion. Intensive Care Unit (ICU) stay between the two groups was also recorded. The surgeon assessed brain relaxation on a four-point scale (1 = Relaxed, 2 = Satisfactory, 3 = Firm, 4 = Bulging). Appropriate statistical tests were used for comparison; P < 0.05 was considered significant.

Results:

Brain relaxation conditions in the HTS group (relaxed/satisfactory/firm/bulging, n = 28/20/5/3) were better than those observed in the M group (relaxed/satisfactory/firm/bulging, n = 17/21/11/9). The levels of serum sodium were higher in the HTS group (P < 0.001). The average urine output was higher in the M group (5.50 ± 0.75 L) than in the HTS group (4.38 ± 0.72 L) (P < 0.005). There was no significant difference in fluid input, ICU stay, and hospital days between the two groups.

Conclusion:

We concluded that HTS provided better brain relaxation than mannitol during elective supratentorial brain tumor surgery, without affecting ICU and hospital stay.

Stroke volume-directed administration of hydroxyethyl starch (HES 130/0.4) and Ringer’s acetate in prone position during neurosurgery: a randomized controlled trial

PURPOSE

General anesthesia in the prone position is associated with hypotension. We studied stroke volume (SV)-directed administration of hydroxyethyl starch (HES 130 kDa/0.4) and Ringer’s acetate (RAC) in neurosurgical patients operated on in a prone position to determine the volumes required for stable hemodynamics and possible coagulatory effects.

METHODS

Thirty elective neurosurgical patients received either HES (n = 15) or RAC (n = 15). Before positioning, SV measured by arterial pressure waveform analysis was maximized by fluid boluses until SV did not increase more than 10 %. SV was maintained by repeated administration of fluid. RAC 3 ml/kg/h was infused in both groups. Thromboelastometry assessed coagulation. Mann–Whitney U test, Wilcoxon signed-rank test, ANOVA on ranks, and a linear mixed model were applied.

RESULTS

Comparable hemodynamics were achieved with the mean cumulative (SD) boluses of HES or RAC 240 (51) or 267 (62) ml (P = 0.207) before positioning, 340 (124) or 453 (160) ml (P = 0.039) 30 min after positioning, and 440 (229) or 653 (368) ml at the end of surgery (P = 0.067). The mean dose of basal RAC infusion was 813 (235) and 868 (354) ml (P = 0.620) in the HES and RAC group, respectively. Formation and maximum strength of the fibrin clot were decreased in the HES group. Intraoperative blood loss was comparable between groups (P = 0.861).

CONCLUSION

The amount of RAC needed in the prone position was 25 % greater. The cumulative dose of 440 ml HES induced a slight disturbance in fibrin formation and clot strength. We suggest cautious administration of HES during neurosurgery.

Perioperative fluid restriction

Perioperative fluid management of the colorectal surgical patient has evolved significantly over the last five decades. Older notions espousing aggressive hydration have been shown to be associated with increased complications. Newer data regarding fluid restriction has shown an association with improved outcomes. Management of perioperative fluid administration can be considered in three primary phases: In the preoperative phase, data suggests that avoidance of preoperative bowel preparation and avoidance of undue preoperative dehydration can improve outcomes. Although the type of intraoperative fluid given does not have a significant effect on outcome, data do suggest that a restrictive fluid regimen results in improved outcomes. Finally, in the postoperative phase of fluid management, a fluid-restrictive regimen, coupled with early enteral feeding also seems to result in improved outcomes.

Decreased risk of acute kidney injury with intracranial pressure monitoring in patients with moderate or severe brain injury

OBJECT

The authors undertook this study to evaluate the effects of continuous intracranial pressure (ICP) monitoring-directed mannitol treatment on kidney function in patients with moderate or severe traumatic brain injury (TBI).

METHODS

One hundred sixty-eight patients with TBI were prospectively assigned to an ICP monitoring group or a conventional treatment control group based on the Brain Trauma Foundation guidelines. Clinical data included the dynamic changes of patients' blood concentrations of cystatin C, creatinine (Cr), and blood urea nitrogen (BUN); mannitol use; and 6-month Glasgow Outcome Scale (GOS) scores.

RESULTS

There were no statistically significant differences with respect to hospitalized injury, age, or sex distribution between the 2 groups. The incidence of acute kidney injury (AKI) was higher in the control group than in the ICP monitoring group (p < 0.05). The mean mannitol dosage in the ICP monitoring group (443 ± 133 g) was significantly lower than in the control group (820 ± 412 g) (p < 0.01), and the period of mannitol use in the ICP monitoring group (3 ± 3.8 days) was significantly shorter than in the control group (7 ± 2.3 days) (p < 0.01). The 6-month GOS scores in the ICP monitoring group were significantly better than in the control group (p < 0.05). On the 7th, 14th, and 21st days after injury, the plasma cystatin C and Cr concentrations in the ICP-monitoring group were significantly higher than the control group (p < 0.05).

CONCLUSIONS

In patients with moderate and severe TBI, ICP-directed mannitol treatment demonstrated a beneficial effect on reducing the incidence of AKI compared with treatment directed by neurological signs and physiological indicators.

Stroke volume-directed administration of hydroxyethyl starch or Ringer's acetate in sitting position during craniotomy

BACKGROUND

To determine the volumes required for stable haemodynamics and possible effects on the coagulation, we studied stroke volume (SV)-directed administration of hydroxyethyl starch (HES 130 kDa/0.4) and Ringer's acetate (RAC) in neurosurgical patients operated on in a sitting position.

METHODS

Thirty craniotomy patients were randomised to receive either HES or RAC. Before positioning, SV, measured by arterial pressure waveform analysis, was maximised by boluses of fluid until SV did not increase more than 10%. SV was maintained by repeated administration of fluid. RAC 3 ml/kg/h was infused in both groups during surgery.

RESULTS

Comparable haemodynamics were achieved with the mean [standard deviation (SD)] cumulative doses of HES or RAC 271 (47) or 264 (50) ml (P = 0.699) before the sitting position. Mean (SD) doses of HES or RAC at 30 min after the positioning were 343 (94) or 450 (156) ml (P = 0.036), and at the end of surgery 464 (284) or 707 (425) ml, respectively (P = 0.087). The intraoperative fluid balance was more positive in the RAC than in the HES group [P = 0.044, 95% confidence interval (CI) -978 to -14]. Cardiac and stroke volume indexes [CI and stroke volume index (SVI)] increased in the HES group (P < 0.05) but not in the RAC group [non significant (N.S.)]. Neither coagulation profile nor blood loss differed between the groups.

CONCLUSION

Fluid filling with HES boluses resulted in a positive response in CI and SVI during the sitting position. The 34% smaller volume of HES than crystalloid and less positive fluid balance in the HES group might be important in craniotomy patients with decreased brain compliance.

Current purpose and practice of hypertonic saline in neurosurgery: a review of the literature

OBJECTIVE

To review and summarize controversies and current concepts regarding the use of hypertonic saline during the perioperative period in neurosurgery.

METHODS

Relevant literature was searched on PubMed and Scopus electronic databases to identify all studies that have investigated the use of hypertonic saline in neurosurgery.

RESULTS

Fluid management during the course of neurosurgical practice has been debated at length, especially strategies to control intracranial pressure and small volume resuscitation. The goal of fluid therapy includes minimizing cerebral edema, preserving intravascular volume, and maintaining cerebral perfusion pressure. Mannitol is widely recognized as the gold standard for treating intracranial hypertension but can result in systemic hypotension. Thus, hypertonic saline provides volume expansion and may improve cerebral and systemic hemodynamics. Recently published prospective data, however, regarding the use of osmotic agents fails to establish clear guidelines in neurosurgical patients.

CONCLUSIONS

We suggest that hypertonic saline will emerge as an alternative to mannitol, especially for a long-term use or multiple doses are needed and lead to a great opportunity for collaborative research.

Hydroelectrolytic balance and cerebral relaxation with hypertonic isoncotic saline versus mannitol (20%) during elective neuroanesthesia

BACKGROUND AND OBJECTIVES

Cerebral relaxation during intracranial surgery is necessary, and hiperosmolar therapy is one of the measures used to this end. Frequently, neurosurgical patients have sodium imbalances. The objective of the present study was to quantify and determine cerebral relaxation and duration of hydroelectrolytic changes secondary to the use of mannitol versus hypertonic isoncotic solution (HIS) during neurosurgery.

METHODS

Cerebral relaxation and hydroelectrolytic changes were evaluated in 29 adult patients before de beginning of infusion, and 30 and 120 minutes after the infusion of equiosmolar loads of approximately 20% mannitol (250 mL) or HIS (120 mL). The volume of intravenous fluids infused and diuresis were recorded. A p < 0.05 was considered significant.

RESULTS

A statistically significant difference in cerebral relaxation between both groups was not observed. Although several changes in electrolyte levels and acid-base balance with mannitol or HIS reached statistical significance only the reduction in plasma sodium 30 minutes after infusion of mannitol, mean of 6.42 ± 0.40 mEq.L(-1), and the increase in chloride, mean of 5.41 ± 0.96 mEq.L(-1) and 5.45 ± 1.45 mEq.L(-1) 30 and 120 minutes after infusion of HIS, caused a transitory dislocation of serum ion levels from normal range. The mannitol (20%) group had a significantly greater diuresis at both times studied compared with HIS group.

CONCLUSIONS

A single dose of hypertonic isoncotic saline solution [7.2% NaCl/6% HES (200/0.5)] and mannitol (20%) with equivalent osmolar loads were effective and safe in producing cerebral relaxation during elective neurosurgical procedures under general anesthesia.

Short-term effectiveness of different volume replacement therapies in postoperative hypovolaemic patients

BACKGROUND AND OBJECTIVE

To examine the kinetics of volume loading with crystalloid and colloid infusions in critically ill patients after major surgery, using the pulse contour cardiac output (PiCCO) monitoring technique.

METHODS

This prospective, randomized, multicentre study of 11 ICUs involved 200 mixed postoperative hypovolaemic patients (50 patients per group) in Hungary. Patients received 10 ml kg of lactated Ringer's solution, succinylated gelatin 4% w/v, 130/0.4 hydroxyethyl starch 6% w/v (HES) or human albumin 5% w/v over 30 min. A complete haemodynamic profile was obtained at 30, 45, 60, 90 and 120 min after baseline. The peak haemodynamic effects, the 120 min changes compared with baseline, the area under the curve (AUC) for the haemodynamic parameters over 120 min and the haemodilution effect of the solutions were analysed. The primary outcome was to compare the AUCs and the secondary outcome was to evaluate the haemodynamic changes at 120 min.

RESULTS

There were significant differences in the AUCs of the haemodynamic parameters between colloids and lactated Ringer's solution in the cardiac index and global end-diastolic volume index (GEDVI); human albumin vs. lactated Ringer's solution in stroke volume variation (SVV); and succinylated gelatin, HES vs. lactated Ringer's solution in the oxygen delivery index (DO2I). Colloid infusions (mainly HES and human albumin) at 120 min caused significant changes in central venous pressure, cardiac index, GEDVI, SVV, DO2I and central venous oxygen saturation compared with baseline. The haemodilution effect was significantly greater in colloids vs. lactated Ringer's solution.

CONCLUSION

In postoperative hypovolaemic patients, lactated Ringer's solution can significantly improve haemodynamics at the end of volume loading, but this effect completely disappears at 120 min. Ten millilitres per kilogram of colloid bolus (especially HES) improved the haemodynamics at 120 min; however, this was by only 5-25% compared with baseline. The colloids caused significantly larger AUCs than lactated Ringer's solution, but only in the cardiac index, GEDVI and DO2I, plus human albumin in the SVV.

Resuscitation with hypertonic saline-dextran reduces serum biomarker levels and correlates with outcome in severe traumatic brain injury patients

In the treatment of severe traumatic brain injury (TBI), the choice of fluid and osmotherapy is important. There are practical and theoretical advantages to the use of hypertonic saline. S100B, neuron-specific enolase (NSE), and myelin-basic protein (MBP) are commonly assessed biomarkers of brain injury with potential utility as diagnostic and prognostic indicators of outcome after TBI, but they have not previously been studied in the context of fluid resuscitation. This randomized controlled trial compared serum concentrations of S100B, NSE, and MBP in adult severe TBI patients resuscitated with 250 mL of 7.5% hypertonic saline plus 6% dextran70 (HSD; n = 31) versus 0.9% normal saline (NS; n = 33), and examined their relationship with neurological outcome at discharge. Blood samples drawn on admission (<or=3 h post-injury), and at 12, 24, and 48 h post-resuscitation were assayed by ELISA for the selected biomarkers. Serial comparisons of biomarker concentrations were made by ANOVA, and relationships between biomarkers and outcome were assessed by multiple regression. On admission, mean (+/-SEM) S100B and NSE concentrations were increased 60-fold (0.73 +/- 0.08 microg/L) and sevenfold (37.0 +/- 4.8 microg/L), respectively, in patients resuscitated with NS, compared to controls (0.01 +/- 0.01 and 6.2 +/- 0.6, respectively). Compared with NS resuscitation, S100B and NSE were twofold and threefold lower in HSD-treated patients and normalized within 12 h. MBP levels were not significantly different from controls in either treatment arm until 48 h post-resuscitation, when a delayed increase (0.58 +/- 0.29 microg/L) was observed in NS-treated patients. Biomarkers were elevated in the patient group showing an unfavorable outcome. HSD-resuscitated patients with favorable outcomes exhibited the lowest serum S100B and NSE concentrations, while maximal levels were found in NS-treated patients with unfavorable outcomes. The lowest biomarker levels were seen in survivors resuscitated with HSD, while maximal levels were in NS-resuscitated patients with fatal outcome. Pre-hospital resuscitation with HSD is associated with a reduction in serum S100B, NSE, and MBP concentrations, which are correlated with better outcome after severe TBI.

Combination therapies for traumatic brain injury: prospective considerations

Traumatic brain injury (TBI) initiates a cascade of numerous pathophysiological events that evolve over time.Despite the complexity of TBI, research aimed at therapy development has almost exclusively focused on single therapies, all of which have failed in multicenter clinical trials. Therefore, in February 2008 the National Institute of Neurological Disorders and Stroke, with support from the National Institute of Child Health and Development, the National Heart, Lung, and Blood Institute, and the Department of Veterans Affairs, convened a workshop to discuss the opportunities and challenges of testing combination therapies for TBI. Workshop participants included clinicians and scientists from a variety of disciplines, institutions, and agencies. The objectives of the workshop were to: (1) identify the most promising combinations of therapies for TBI; (2) identify challenges of testing combination therapies in clinical and pre-clinical studies; and (3) propose research methodologies and study designs to overcome these challenges. Several promising combination therapies were discussed, but no one combination was identified as being the most promising. Rather, the general recommendation was to combine agents with complementary targets and effects (e.g., mechanisms and time-points), rather than focusing on a single target with multiple agents. In addition, it was recommended that clinical management guidelines be carefully considered when designing pre-clinical studies for therapeutic development.To overcome the challenges of testing combination therapies it was recommended that statisticians and the U.S. Food and Drug Administration be included in early discussions of experimental design. Furthermore, it was agreed that an efficient and validated screening platform for candidate therapeutics, sensitive and clinically relevant biomarkers and outcome measures, and standardization and data sharing across centers would greatly facilitate the development of successful combination therapies for TBI. Overall there was great enthusiasm for working collaboratively to act on these recommendations.